technetium-tc-99m-exametazime and Brain-Diseases

Topics: Brain Diseases; Humans; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Brain imaging has become an integral part of the evaluation of neurological and psychiatric disorders. Functional imaging techniques, SPECT and PET, together with structural modalities, CT and MRI, are widely employed. Functional imaging studies are routinely used in the diagnostic workup of patients with well-characterized neurological disorders, such as epilepsy and brain tumors, and have a growing role in research on psychiatric disorders without known mechanisms such as depression and schizophrenia. Furthermore, many well-defined neurological disorders manifest prominent psychiatric symptomatology which may pose difficulties in differential diagnosis. This review addresses the current knowledge of SPECT findings in patients who present with psychiatric phenomena, associated with disorders at the interface of neurology and psychiatry.

Topics: Alzheimer Disease; Brain; Brain Damage, Chronic; Brain Diseases; Brain Injuries; Brain Neoplasms; Dementia; Diagnosis, Differential; Epilepsy, Temporal Lobe; Humans; Huntington Disease; Neurocognitive Disorders; Organotechnetium Compounds; Oximes; Parkinson Disease; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

This review critically evaluates the current role of single photon emission tomography (SPET) imaging in the clinical management of patients with dementia. The classification of the dementias is discussed and the clinical and pathological features of the various dementing illnesses are described. Typical appearances on cerebral blood flow imaging are presented for each of the conditions, together with the findings on D2 dopaminergic receptor and muscarinic receptor imaging where this is relevant. The review concludes with a section on the clinical value of SPET imaging in dementia. SPET imaging can make a valuable contribution to the accurate clinical differentiation of dementia, providing findings are interpreted in the light of neurological evaluation and structural imaging. The possible future role of SPET imaging in the prediction and evaluation of response to future therapeutic agents is discussed.

Topics: Alzheimer Disease; Brain; Brain Diseases; Dementia; Humans; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

Topics: Adult; Aged; Astrocytoma; Brain; Brain Diseases; Brain Neoplasms; Cerebral Infarction; Electroencephalography; Female; Humans; Magnetic Resonance Spectroscopy; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

Topics: Brain Diseases; Brain Neoplasms; Child; Deoxyglucose; Epilepsy; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Humans; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

Nuclear medicine techniques have been powerful tools in neurology since their introduction. Computed tomography, magnetic resonance imaging and newer techniques, i.e. MR spectroscopy and angiography, sonography, Doppler sonography and EEG mapping with squid elements have overtaken most earlier nuclear medicine techniques for neurological diagnosis. Positron emission tomography is the gold standard for in vivo research in neurophysiology and pathology. The introduction of SPECT and the development of such tracers as 99mTc-HMPAO (99mTc-d,l-hexamethylpropylenaminoxim) and, more recently, 123I-iomazenil and 123I-IBZM (123I-3-iodo-6-methoxybenzamide) allowed closer examination of the perfusion of the brain and neuroreceptor density mapping in more than the few institutions that can afford PET and the production of special tracers marked with a positron emitting nucleus. Nuclear medicine's future will be based on neuroreceptor density mapping, as further tracers will become commercially available and no other technique can probably show such low concentrations of the receptors. Probably MR techniques will be used for brain's perfusion measurement in future. For examination of a limited cerebral region xenon-enhanced CT is an alternative to perfusion measurements with HMPAO, or a very interesting supplement. Of the old techniques in nuclear medicine, examination of the liquor dynamics is still feasible and well supplemented by SPECT.

Topics: Benzamides; Brain Diseases; Flumazenil; Humans; Iodine Radioisotopes; Organotechnetium Compounds; Oximes; Pyrrolidines; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

In the past 7 years, single photon emission computed tomography (SPECT) has evolved from an interesting nuclear medicine technique rarely performed because of technical difficulties into a valuable clinical tool in the management of cancer cases. The development of stable multidetector instruments with collimators and gantries specifically designed for SPECT and the introduction of new radiopharmaceuticals recently approved by the U.S. Food and Drug Administration have rapidly moved SPECT from the field of clinical investigation to clinical practice. SPECT is a valuable addition to other tomographic modalities capable of displaying the physiology of disease as well as anatomy. In this work the authors describe the role of SPECT in a cancer center and, in particular, how they use it to solve clinical problems. They also review the published literature, when appropriate. The authors have found SPECT of particular value in evaluation of myocardial ischemia, in differentiating tumor recurrence from posttherapy changes in the lymphomas, in tumor diagnosis and surveillance, and in separating hemangioma from malignant lesions in the liver.

Topics: Abdomen; Amphetamines; Antibodies, Monoclonal; Bone Diseases; Brain Diseases; Cardiovascular Diseases; Humans; Neoplasms; Organotechnetium Compounds; Oximes; Quality Control; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

Cerebral blood flow (CBF) can be quantified non-invasively using the brain perfusion index (BPI) determined from radionuclide angiographic data generated with 99mTc-hexamethylpropylene amine oxime (99mTc-HMPAO). When measuring the BPI, manual drawing of regions of interest (ROIs) (manual ROI method) for the extraction of the arterial input function (AIF) can lead to serious individual differences. The purpose of this study was to apply the fuzzy c-means (FCM) clustering method to determine AIF, and to investigate its usefulness in comparison with the manual ROI method. Radionuclide angiography was performed using a bolus injection of about 555 MBq of 99mTc-HMPAO, followed by sequential imaging (1 sec/frame x 120 s) using a solid-state gamma camera, and the BPI values were calculated using spectral analysis. To investigate the dependence of BPI on the ROI size, we drew five ROIs with different sizes over the aortic arch, and calculated the BPI using the manual ROI method [BPI(manual)] and the FCM clustering method [BPI(FCM)]. Furthermore, we asked 10 individuals to draw ROIs to investigate the inter-operator variability of the two methods. The mean and standard deviation (SD) of BPI(manual) increased with increasing ROI size, whereas the mean of BPI(FCM) was almost constant regardless of the ROI size; the SD of BPI(FCM) was smaller than that of BPI(manual). The inter-operator variability of the FCM clustering method was smaller than that of the manual ROI method. These results suggest that the FCM clustering method appears to be useful for the measurement of BPI, because it allows a reliable and objective determination of AIF.

Topics: Aged; Algorithms; Arteries; Brain; Brain Diseases; Cerebrovascular Circulation; Cluster Analysis; Female; Fuzzy Logic; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Models, Biological; Radioisotope Dilution Technique; Radionuclide Angiography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Technetium Tc 99m Exametazime

Radionuclide angiography with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) or technetium-99m ethyl cysteinate dimer (99mTc-ECD) enables the non-invasive estimation of absolute cerebral blood flow (CBF) to be determined by using spectral analysis (SA). We previously demonstrated the clinical use of SA; however, this method involves a few manual steps. The aim of this study was to evaluate the interobserver variability of CBF estimations made using SA and compare these results with those obtained by using graphical analysis (GA). In twenty patients with various brain diseases (27-74 years old), radionuclide angiography examinations were performed using 99mTc-labeled compounds (10 patients, 99mTc-HMPAO; 10 patients, 99mTc-ECD). Bilateral cerebral hemispheres were studied in all patients, and the brain perfusion index (BPI) values were estimated using SA and GA. The interobserver variability between two observers was then assessed. A good correlation between the BPI values assessed using both SA (BPI(S)) and GA (BPI(G)) was obtained. The correlation coefficient for BPI(S) (r = 0.987) was almost the same as that for BPI(G) (r = 0.982). The degree of interobserver variability was not affected by the measurement of elevated BPI values. Measurements carried out by two observers using both SA and GA exhibited a similar degree of interobserver variability. SA appears to have a satisfactory interobserver variability and may be more suitable for clinical applications.

Topics: Algorithms; Brain; Brain Diseases; Cerebrovascular Circulation; Cysteine; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Observer Variation; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Technetium Tc 99m Exametazime

Cerebral blood flow (CBF) can be non-invasively quantified using the brain perfusion index (BPI), determined from radionuclide angiographic data generated by technetium-99m hexamethylpropylene amine oxime ((99m)Tc-HMPAO). We previously reported the use of a spectral analysis (SA) method using (99m)Tc-HMPAO to calculate the BPI. In this report, we demonstrate an automatic method for determining the optimal BPI value and compare the optimal BPI values with the absolute CBF values measured using H(2)(15)O positron emission tomography (PET). Bilateral cerebral hemispheres of 11 patients with various brain diseases were examined using (99m)Tc-HMPAO. In the automatic SA procedure, the radioactivity curve for the aortic arch ( C (a)) was shifted by 0-10 s. The radioactivity curve for the brain ( C (b)) was estimated using the shifted C (a), and the error value between the actually measured and the estimated C (b) (Err) was calculated. When the Err was at a minimum, the BPI value was defined as optimal BPI. The difference in BPI from the optimal BPI was calculated as |BPI - optimal BPI| / optimal BPIx100 (%). In all participants, an H(2)(15)O PET examination was also performed, and the BPI values were compared with the absolute CBF values measured using H(2)(15)O PET (mCBF(PET)). The difference between BPI and the optimal BPI increased significantly from 4.87%+/-1.69% to 18.38%+/-3.93% (mean+/-SD) when the Err value increased. The optimal BPI value ( y) was well correlated with the mCBF(PET) value ( x) ( y=0.21 x-0.0075, r=0.800). Our results suggest that this automatic SA method provides an accurate estimate of BPI that can be used for the quantification of CBF using (99m)Tc-HMPAO SA.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Middle Aged; Quality Control; Radionuclide Angiography; Radiopharmaceuticals; Sensitivity and Specificity; Spectrum Analysis; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

To develop non-invasive regional cerebral blood flow (rCBF) measurements using technetium-99m ethyl cysteinate dimer (99mTc-ECD) and single-photon emission tomography (SPET), the same graphical analysis as was described in our previous reports using technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was applied to time-activity data for the aortic arch and brain hemispheres after intravenous injection of 99mTc-ECD. Hemispherical brain perfusion indices (BPI) for 99mTc-ECD showed a highly significant correlation (n = 22, r = 0.935, P = 0.0001) with those for 99mTc-HMPAO in 11 patients who underwent both tracer studies. Using both linear regression line equations between 99mTc-ECD BPI and 99mTc-HMPAO BPI and between 99mTc-HMPAO BPI and mean cerebral blood flow (CBF) values obtained from a xenon-133 inhalation SPET method in a previous study, 99mTc-ECD BPI was converted to 133Xe CBF values (y = 2.60 chi + 9.8). Then raw SPET images of 99mTc-ECD were converted to rCBF maps using Lassen's correction algorithm. In this algorithm, the correction factor alpha was fixed to 1.5, 2.6 and infinite. In the comparison of rCBF values for 99mTc-ECD SPET with those for 99mTc-HMPAO SPET in 396 regions of interest in the aforementioned 11 patients, the fixed correction factor alpha of 2.6 gave nearly the same rCBF values for 99mTc-ECD (50.1 +/- 16.9 ml/100 g/min, mean +/- SD) as for 99mTc-HMPAO (49.9 +/- 17.3 ml/100 g/min). In conclusion, the same non-invasive method as has been used in 99mTc-HMPAO studies is applicable to a 99mTc-ECD study for the measurement of rCBF without any blood sampling.

Topics: Adult; Aged; Algorithms; Brain; Brain Diseases; Cysteine; Female; Humans; Linear Models; Male; Middle Aged; Organotechnetium Compounds; Oximes; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The clinical experience with the Toshiba GCA-9300A single photon emission tomography (SPET) system is discussed along with typical acquisition protocols for various SPET studies. The system was used to perform SPET studies in normals and in a variety of brain and body disorders. Its three Anger-type gamma cameras forming a triangular aperture offer a substantial increase in sensitivity compared to a single rotating gamma camera. This has allowed the routine use of lead fanbeam super high-resolution collimators (SHR FB) for 99Tcm-hexamethylpropyleneamine oxime (HMPAO) brain SPET studies and high-resolution parallel-hole collimators (HR PH) for cardiac and other body studies. The resulting improvement in spatial resolution coupled with the ease of patient positioning and the greater patient throughput compared to a conventional tomographic gamma camera, will enhance the role of brain and body SPET for both routine and research purposes.

Topics: Bone and Bones; Brain; Brain Diseases; Chest Pain; Humans; Kidney; Male; Middle Aged; Myocardial Ischemia; Organotechnetium Compounds; Oximes; Reference Values; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

To investigate whether topographic analysis of EEG mapping and technetium-99m (99mTc) hexamethylpropylenamine oxide (HMPAO) brain single-photon emission computed tomography (SPECT) can detect cerebral anomalies in the acute phase of carbon monoxide poisoning.. Twelve patients aged 18 to 55 years with severe carbon monoxide poisoning and no history of neurologic disorder were evaluated. Either nasal (5 patients) or hyperbaric (7 patients) oxygen therapy was administered. Criteria for hyperbaric oxygen therapy were blood CO of more than 20%, loss of consciousness, pregnancy, or signs of cardiac injury. After oxygen treatment, all patients had a blood CO value of 0% and no patient had persistent acute signs of toxicity. Patients then were investigated by confentional EEG, EEG mapping, and 99mTc HMPAO brain SPECT. These procedures were performed on the day of admission.. After nasal (5 patients) or hyperbaric (7 patients) oxygen therapy was administered, 12 adults with severe carbon monoxide poisoning were evaluated. All studies were performed on the day of admission.. Conventional EEG, EEG mapping, and 99mTc HMPAO brain SPECT.. While classic EEG was normal in 9 of 12 patients and showed diffuse anomalies in 3, EEG mapping and 99mTc HMPAO brain SPECT demonstrated unilateral or bilateral regional anomalies in 8 of 12 patients. Anomalies were localized in temporo-parieto-occipital areas, the watershed areas of the major cerebral arteries, or in temporal cortex.. These preliminary results suggest that EEG mapping and 99mTc HMPAO brain SPECT can be complementary tools to diagnose early regional cerebral anomalies in carbon monoxide-poisoned patients.

Topics: Acute Disease; Adolescent; Adult; Brain Diseases; Brain Mapping; Carbon Monoxide; Carbon Monoxide Poisoning; Electroencephalography; Female; Humans; Hyperbaric Oxygenation; Male; Middle Aged; Organotechnetium Compounds; Oximes; Oxygen Inhalation Therapy; Sensitivity and Specificity; Severity of Illness Index; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

A consensus on the brain dysfunction(s) underlying the delusions of Alzheimer's Dementia (AD) remains to be achieved. The aim of the present study was to test the hypothesis that content-based categorization of delusional ideas manifests as dysfunction of category-specific brain regions.. Fifty-nine consecutive first-visit AD outpatients underwent Single Photon Emission Computed Tomography (SPECT), Mini-Mental State Examination, and Behavioral Pathology in Alzheimer's Disease Frequency-Weighted Severity scale (BEHAVE-AD-FW) to assess cerebral blood flow (CBF), cognitive function, and delusion, respectively. SPECT images were analyzed by SPM5.. CBF decreased at the temporal poles and right inferior temporal gyrus in "delusion of theft," at the temporal poles in "suspiciousness/paranoia," at the right parahippocampal gyrus and insula in "abandonment," and at the right amygdala in "Residence is not home.". Our findings offer a perspective on the discrete categories of the pathological thoughts of AD patients that have previously been lumped together as "delusions." Dysfunction of the temporal poles may be associated with a socioemotional deterioration that may include pathological suspiciousness. Delusion of theft may be a manifestation of socioemotional deterioration and poor insight. Emotional factors may be essential for delusions of abandonment and "not home."

Topics: Aged; Alzheimer Disease; Brain Diseases; Cerebrovascular Circulation; Cognition; Cross-Sectional Studies; Delusions; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Neuropsychological Tests; Radiopharmaceuticals; Severity of Illness Index; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

We describe 5 patients with complex visual disturbances in the absence of ocular pathology who were ultimately diagnosed with posterior cortical atrophy (PCA). The presence of visual cortical symptoms, neuroimaging findings and clinical evolution led to the diagnosis 1-5 years after the onset of visual symptoms. Age of onset ranged from 50-66 years. In 3 cases, magnetic resonance imaging (MRI) of the brain demonstrated predominantly right posterior cortical atrophy. The other 2 patients had nonspecific MRI findings but the diagnosis was established given the findings on clinical examination and positron emission tomography (PET). All progressed to global dementia and an autopsy confirmed the diagnosis of Alzheimer disease in one patient. The possibility of PCA should be considered when a patient presents with complex visual symptoms in the absence of ocular pathology. Early neurological assessment may avoid diagnostic delay.

Topics: Aged; Atrophy; Brain Diseases; Cerebral Cortex; Female; Fluorodeoxyglucose F18; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Positron-Emission Tomography; Retrospective Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Vision Disorders

Previous reports document transient improvements after daily zolpidem (CAS 82626-48-0) in patients with brain damage. This multi-patient study evaluates the response to zolpidem in neurologically disabled patients, using 99mTcHMPAO brain SPECT scans and clinical rating scales.. 23 of 41 consecutive adult patients, at least 6 months after brain damage were identified as neurologically disabled patients by scoring less than 100/100 on the Barthel Index. Causes of their brain damage included stroke (n = 12), traumatic brain injury (n = 7), anaphylaxis (n = 2), drugs overdose (n = 1) and birth injury (n = 1). The selected 23 patients had a baseline 99mTcHMPAO brain SPECT scan before starting daily zolpidem therapy and a second within two weeks of therapy, performed 1 h after 10 mg oral zolpidem. Scans were designated as improved when at least two of three assessors detected improvement after zolpidem. The rest were designated non improved. After four months daily zolpidem therapy, patients were rated on the Tinetti Falls Efficacy Scale (TFES) before and after zolpidem. The TFES ratings were compared using a Wilcoxon non parametric signed rank test. Scan improvers were compared with non improvers, using a two sample t test with unequal variance.. Mean overall improvement after zolpidem on TFES was 11.3%, from 73.4/100 to 62.1/100 (p = 0.0001). 10/23 (43%) patients improved on SPECT scan after zolpidem. Their mean TFES improvement was 19.4% (+/- 16.75) compared with 5.08% (+/- 5.17) in 13/23 non improvers (p = 0.0081).. This prospective study adds further evidence to previous reports of zolpidem efficacy in patients with established brain damage.

Topics: Activities of Daily Living; Adolescent; Adult; Aged; Brain; Brain Diseases; Brain Injuries; Female; Humans; Hypnotics and Sedatives; Image Processing, Computer-Assisted; Male; Middle Aged; Neurologic Examination; Pyridines; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Young Adult; Zolpidem

Fahr's disease is a rare neurodegenerative syndrome, characterized by massive symmetrical intracerebral calcifications of the basal ganglia, dentate nuclei of the cerebellum, and the adjacent parenchyma. Computerized tomography (CT) is considerably more sensitive to detect these intracranial calcifications than other imaging modalities. The clinical, CT scan, and 99(m)Tc-D,L-hexamethylpropylene amine oxime (99(m)Tc-HMPAO) brain perfusion single-photon emission computerized tomography (SPECT) findings in a 42-year-old woman with Fahr's disease are reported, and the clinical utility of 99(m)Tc-HMPAO SPECT findings in Fahr's disease is discussed in this article. In conclusion, 99(m)Tc-HMPAO brain perfusion SPECT seems to be useful in the clinical approach to Fahr's disease, and may provide more specific and clinically relevant information when compared with anatomical imaging.

Topics: Adult; Brain; Brain Diseases; Calcinosis; Female; Humans; Neurodegenerative Diseases; Syndrome; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Chernobyl Nuclear Accident; Humans; Occupational Diseases; Radiation Dosage; Radiation Injuries; Radiopharmaceuticals; Severity of Illness Index; Technetium Tc 99m Exametazime; Time Factors

There were 10 acutely CO poisoned study patients without CNS history (head traumas, epilepsy, dementia, migraine or alcoholic diseases) in whom (99m)Tc-HmPAO SPET, HMRS and neuropsychological testing were performed. 99mTc-HmPAO SPET and neuropsychological testing were performed twice: in acute phase and at six months post CO exposure. HMRS was carried out at 8 months post CO exposure. A multidimensional analysis of variance (MANOVA) was used to statistical analysis. Regional CBF disturbances in acute phase of CO poisoning were observed in frontal cortex, basal ganglia and parietal cortex respectively. The most reversible, as seen in control (99m)Tc-HmPAO SPET examination, were the changes observed in parietal cortex. Diffuse generalized cortex hypoperfusion, both in acute phase and at 6 months post exposure, was seen only in one the patient. In all of the examined patients different elevation in mobile lipid or/and lactate concentration in frontal lobe or/and basal ganglia was revealed by HMRS evaluation at eight months post acute CO exposure. Results of neuropsychological testing at baseline and at 6 months partially correlated with neuro-imagine techniques applied.

Topics: Acute Disease; Adolescent; Adult; Analysis of Variance; Brain Diseases; Carbon Monoxide Poisoning; Cerebrovascular Circulation; Evaluation Studies as Topic; Female; Follow-Up Studies; Humans; Magnetic Resonance Spectroscopy; Male; Neuropsychological Tests; Radiopharmaceuticals; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Time Factors; Tomography, Emission-Computed, Single-Photon

The relationship between the mean cerebral blood flow (CBF) and cognitive function was investigated in patients with brain insult. This study included 72 patients aged 24-85 years treated for the following diseases: cerebral infarction (21), intracerebral hemorrhage (4), subarachnoid hemorrhage (2), brain tumor (14), cerebral contusion (12), normal pressure hydrocephalus (13), Alzheimer's disease (2), and others (4). First-pass radionuclide angiography using Technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was performed for the measurement of the mean CBF, and the Sturb-Black Mental Status Examination for the neuropsychological evaluation. The mean CBF and the score of the neuropsychological test were significantly reduced compared with those of the age-matched controls. Regardless of etiology, the mean CBF and the score of neuropsychological test were significantly reduced, and a significant correlation was observed except for the patients with cerebral contusion. The quantitative measurement of CBF using 99mTc-HMPAO is reliable to estimate the neuropsychological state.

Topics: Adult; Aged; Aged, 80 and over; Analysis of Variance; Blood Circulation Time; Brain Diseases; Case-Control Studies; Cerebrovascular Circulation; Cognition Disorders; Female; Functional Laterality; Humans; Male; Middle Aged; Neuropsychological Tests; Radiopharmaceuticals; Retrospective Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Carbon monoxide (CO) poisoning continues to be a significant health problem. An early assessment of organs injury due to carbon monoxide poisoning is even more difficult than confirming the diagnosis of CO poisoning. Numerous neuroimaging techniques have been used to evaluate CO intoxication. The aim of this pilot study was to estimate the regional cerebral perfusion in CO acutely poisoned patients using 99mTc-HmPAO SPET. Disturbances in cerebral perfusion mainly in frontal, parietal cortex and basal ganglia were observed in 17 (85%) of 20 examined CO poisoned patients. 99mTc-HmPAO scintigraphy seems be useful in demonstration of early CNS dysfunction and estimation to what extent perfusion abnormalities influence the brain injury. A further study to evaluate the rCBF in relation to poisoning severity scoring are needed.

Topics: Acute Disease; Adolescent; Adult; Brain Diseases; Carbon Monoxide Poisoning; Cerebrovascular Circulation; Female; Humans; Male; Pilot Projects; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Topics: Adult; Brain; Brain Diseases; Choristoma; Epilepsy, Complex Partial; Female; Humans; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

An objective and practicable method to evaluate the brain tolerance to unilateral carotid artery occlusion was attempted. Ten consecutive cases were studied. Endovascular trial balloon occlusion of the unilateral carotid artery in conjunction with single-photon emission computed tomography (SPECT) as well as digital subtraction angiography (DSA) and clinical neurological evaluation was routinely performed for those patients who might undergo permanent occlusion of the internal (ICA) and/or common carotid artery (CCA). The result of SPECT was analyzed semi-quantitatively and compared with the baseline data as well as the data from contralateral side. The relative symmetry index (rS) of side-to-side radioactivity counts relevant to the baseline was calculated. One subject failed the balloon occlusion test (BOT), even though an angiographically adequate collateral circulation was observed. The rS of the patient was 74.5%. The remaining patients passed the 45-min BOT without any neurological deficiency induced. Their value of rS was 97.8% +/- 4.4%. Based the BOT results, the left ICA, CCA and external carotid artery were excised in one patient, CCA-ICA reconstructions after carotid occlusions were performed in three. The carotid arteries were saved in five. For one patient, the ICA was occluded spontaneously during the BOT. There were no neurological impairments developed after the surgery. With this BOT technique, clinically silent areas of decreased perfusion might be detected. We suggest it be a routine preparatory to carotid manipulations.

Topics: Adult; Aged; Angiography, Digital Subtraction; Balloon Occlusion; Brain; Brain Diseases; Carotid Artery Diseases; Central Nervous System Neoplasms; Humans; Male; Middle Aged; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The authors present a case of linear nevus sebaceous syndrome (LNSS) with atrophy of bilateral frontotemporal areas of the brain, left cerebellum and hippocampus, and bilateral uncal dysplasia demonstrated by magnetic resonance imaging (MRI). Magnetic resonance angiography revealed bilateral internal carotid artery hypoplasia with absence of flow in the anterior and middle cerebral arteries. Tc-99m HMPAO brain SPECT demonstrated more areas of perfusion defects while MRI detected volume loss and gliosis in affected areas. Tc-99m HMPAO brain SPECT may be more useful for revealing absent or decreased perfusion areas of brain lesions than MRI in LNSS.

Topics: Brain; Brain Diseases; Humans; Infant, Newborn; Magnetic Resonance Angiography; Male; Neurocutaneous Syndromes; Predictive Value of Tests; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Topics: Adult; Bone Diseases; Brain Diseases; Echinococcosis; Echinococcosis, Hepatic; Female; Humans; Magnetic Resonance Imaging; Parietal Bone; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Ultrasonography

Band heterotopias are an example of genetic generalized neuronal migration disorders that may be present in patients with mild epilepsy and normal or slightly impaired intellect, as well as in patients with intractable epilepsy and mental retardation. The case of a 17-year-old left-handed female patient with epilepsy and normal cognitive development is reported in whom single-photon emission computed tomography (SPECT), proton magnetic resonance spectroscopy, and functional magnetic resonance imaging (fMRI) were performed. MRI revealed the presence of bilateral asymmetric band heterotopia. SPECT revealed a left frontoparietal and occipital hypoperfusion, demonstrating a good correlation with the electroencephalogram abnormalities. Because of the appearance of new types of seizures, the patient underwent a second MRI investigation together with a proton magnetic resonance spectroscopy (MRS) study. MRI confirmed bilateral band heterotopia characterized by greater thickness in the left hemisphere at the frontal and occipital level. MRI and SPECT findings were in agreement with left occipital electroencephalogram abnormalities and with occipital seizure type. Qualitative results of proton MRS revealed normal spectra profiles in the examined left frontal and occipital heterotopic area and in the normal overlying cortex. Later, fMRI was performed. The finger-tapping test of the right hand yielded the activation of both normal left sensory-motor cortex and the facing band heterotopia. In the right hemisphere, only the activation of the sensory-motor neocortex was observed; no involvement of the right misplaced brain tissue was present. This functional behavior could be considered the consequence of poor neuronal representation. On the contrary, the involvement of both band heterotopia and normal cortex observed in the left hemisphere could be the result of many synaptic interconnections. Functional investigations may have an important role in defining the activity of band heterotopia per se and in relation to the overlying neocortex.

Topics: Adolescent; Brain; Brain Diseases; Cell Movement; Choristoma; Dominance, Cerebral; Epilepsy; Female; Humans; Intelligence; Magnetic Resonance Imaging; Mutation, Missense; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

In this study, technetium-99 ((99)Tc)-hexamethylpropyleneamine-oxine single-photon emission computed tomography (SPECT) was performed on 13 children with classic lissencephaly (nine with epileptic seizures, four without seizures). Focal or multifocal hypoperfusions were observed in 12 patients. The hypoperfused areas observed on SPECT scanning did not correlate with the localization of agyric-pachygyric regions in all patients. The distribution of perfusion abnormalities by SPECT and the localization of agyria-pachygyria as detected by magnetic resonance imaging did not correlate strongly. All nine patients with seizures and three of the four patients without seizures had focal or multifocal cerebral blood flow abnormalities on the SPECT scans. The presence of brain perfusion abnormalities detected by SPECT and the occurrence of epileptic seizures did not have a significant relationship. These results suggest that the role of SPECT studies in classic lissencephaly is not clearly defined. More sophisticated methods are needed to clarify the correlation between structural and functional abnormalities of patients diagnosed with lissencephaly.

Topics: Brain; Brain Diseases; Child, Preschool; Electroencephalography; Female; Humans; Infant; Magnetic Resonance Imaging; Male; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

To report and discuss the neuropsychological deficits and neuroimaging findings in a patient with probable Marchiafava-Bignami disease.. A right-handed woman with chronic alcoholism demonstrated mutism, impaired comprehension of spoken language, alexia, and right-handed agraphia. The syndrome of interhemispheric disconnection was manifested by left-handed deficit of constructional ability and agraphia. The patient underwent brain computed tomographic scans, technetium 99 hexylmethylpropylene amineoxime-single photon emission computed tomography, and magnetic resonance imaging (MRI) that also included fluid attenuated inversion recovery images.. Clinical neurology department.. The patient's symptoms were related to scattered lesions of the corpus callosum and to extensive symmetrical lesions of the centrum semiovale. Only the latter were detected by computed tomographic scans. Results of single photon emission computed tomography did not show areas of focal hypoperfusion. Results of fast spinecho MRI showed all lesions were hyperintense in T1-weighted images and hypointense in T2-weighted images. Fluid attenuated inversion recovery images revealed that periventricular lesions had a hypointense core surrounded by a hyperintense rim; callosal lesions were still hyperintense.. We believe that our patient's symptoms are due to the discontinuous affection of the corpus callosum and to the bilateral cutting of the outflow from the cortex. The MRI findings may be interpreted as indicating central necrosis and peripheral demyelination of periventricular lesions and demyelination of the corpus callosum. The combined use of fast spin echo and fluid attenuated inversion recovery MRI reproduced with more accuracy than fast spin echo MRI alone some features of Marchiafava-Bignami disease known from observations at autopsy.

Topics: Adult; Agraphia; Alcoholism; Aphasia; Brain Diseases; Corpus Callosum; Demyelinating Diseases; Dyslexia, Acquired; Female; Functional Laterality; Humans; Magnetic Resonance Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

The authors report a 61-year-old man with chronic viral encephalitis and Koshevnikov syndrome occurring 42 months after initial symptom of right hemiparesis. Serial computed tomography of the brain showed changes in the attenuation of the left temporal lobe lesion over time. Magnetic resonance images of the brain showed enlargement of left temporoparietooccipital lobes with cortical gyral enhancement on T1-weighted images following intravenous administration of gadolinium-DTPA. 99mTc-HMPAO single-photon emission computerized tomography showed increased radioactivity and hyperperfusion in the left temporoparietal region with paradoxically decreased local tissue perfusion at the contralateral right hemisphere. Follow-up magnetic resonance images of the brain 4 years later showed atrophy of bilateral cerebral hemispheres. We postulate that a "transcallosal diaschisis" with subsequent degeneration is a possible mechanism. A brain biopsy from the left temporal lobe lesion showed pictures compatible with viral encephalitis probably herpes simplex encephalitis.

Topics: Atrophy; Brain; Brain Diseases; Cerebrovascular Circulation; Chronic Disease; Contrast Media; Corpus Callosum; Encephalitis, Viral; Epilepsia Partialis Continua; Follow-Up Studies; Gadolinium DTPA; Herpes Simplex; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Occipital Lobe; Parietal Lobe; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

We analyzed the interictal [18F]fluoro-2-deoxy-D-glucose positron emission tomography (FGD-PET) and single photon emission computed tomography with technetium-99m-hexamethyl-propyleneamine oxime (HMPAO-SPECT) in two epileptic patients with periventricular nodular heterotopia (PNH). In both cases, we found both the glucose metabolism and the perfusion of PNH to be almost identical to those of the normal cerebral cortex. The metabolic activity and perfusion in the heterotopic gray matter in a subependymal white matter area probably represent the glucose metabolism and perfusion of the abnormally located gray matter rather than a subclinical ictal phenomenon. FDG-PET and HMPAO-SPECT were thus found to be a useful complement to magnetic resonance imaging in the evaluation of PNH.

Topics: Adult; Brain Diseases; Cerebral Ventricles; Choristoma; Female; Fluorodeoxyglucose F18; Humans; Middle Aged; Periaqueductal Gray; Radiography; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

Topics: Brain; Brain Diseases; Carotid Artery Thrombosis; Carotid Artery, Internal; Cerebellar Diseases; Cerebral Infarction; Child; Female; Heart Septal Defects; Humans; Radiopharmaceuticals; Spleen; Syndrome; Technetium Tc 99m Aggregated Albumin; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Whole-Body Counting

Cytarabine (ara-C) is one of the most effective chemotherapeutic agents in patients with acute leukemia (AL), with a clear dose effect. Use of high-dose ara-C is hampered, however, by a noticeable toxicity, particularly to the CNS. We investigated the usefulness of CNS perfusion imaging with technetium-99m ((99m)Tc)-hexamethyl-propylene-amine oxime (HMPAO) single-photon emission computed tomography (SPECT) concurrent to magnetic resonance imaging (MRI) to specifically assess the effects of standard- and high-dose ara-C in children with AL.. Twenty-six perfusion studies using (99m)Tc-HMPAO SPECT were performed in 12 children (age range, 4 to 15 years) with AL after induction therapy, which consisted of a standard-dose ara-C, immediately after consolidation with high-dose ara-C, and later during follow-up (range, 6 to 44 months). The chemotherapy-related adverse events were monitored and correlated to SPECT and MRI.. After the induction phase, all children were neurologically normal on MRI. On SPECT imaging, four children displayed a slightly heterogeneous perfusion. After high-dose ara-C (4 to 36 g/m(2)), five children had regressive neurologic signs of potential toxic origin. Of these five children, only one had an abnormal MRI scan, whereas all patients showed evidence of diffuse cerebral and/or cerebellar heterogeneous perfusion on SPECT. The seven other patients without any neurologic symptoms had normal MRI scans; SPECT was normal for three patients and abnormal for four patients. On follow-up, for four children who had presented with clinical neurologic toxicity, SPECT improved in three patients and remained unchanged in one patients. In two of these four children, delayed abnormalities (T2 white matter hypersignal and cerebellar atrophy) appeared on MRI scans.. In our series, diffuse heterogeneous brain hypoperfusion is often the sole early objective imaging feature identified by SPECT of high-dose ara-C neurotoxicity, where MRI still demonstrates normal pictures.

Topics: Adolescent; Antimetabolites, Antineoplastic; Brain; Brain Diseases; Cerebellum; Child; Child, Preschool; Cytarabine; Drug Monitoring; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Neurologic Examination; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Obsessive-compulsive disorder (OCD) may result from a range of neurological lesions in frontal and basal ganglia areas. However, relatively few studies have explored functional brain imaging in acquired OCD.. Charts of patients presenting to our Neuropsychiatry Unit where obsessive-compulsive symptoms appeared secondary to neurological lesions were reviewed. Demographic information and clinical diagnoses were collated, and brain SPECT scans reviewed. Six patients with various neurological conditions presented with OCD. All demonstrated decreased blood flow in the temporal lobes as well as cortical perfusion abnormalities in the frontal lobes (focal areas of decreased perfusion in one patient, focal areas of increased perfusion in two, and a combination of focal increased and decreased frontal perfusion in three cases). Abnormal blood flow may be seen in a number of different brain regions in acquired OCD. It is unclear whether these changes reflect primary neurological lesions or secondary changes to compensate for such damage. However, increased frontal blood flow in OCD may be hypothesized to reflect a compensatory mechanism.

Topics: Adult; Brain Diseases; Cerebrovascular Circulation; Craniocerebral Trauma; Female; Frontal Lobe; Humans; Male; Middle Aged; Obsessive-Compulsive Disorder; Radiopharmaceuticals; Retrospective Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

To investigate the clinical, neuropsychological and imaging manifestations of Sjögren's syndrome (SS), a chronic auto-immune disease with peripheral and central nervous system (CNS) involvement.. Fourteen female patients suffering from confirmed SS underwent within 2 weeks: neurological examination, immunological staging, brain MRI, brain 99m Tc-HMPAO SPECT, psychological evaluation and in-depth neuropsychological testing.. All patients showed neuropsychological abnormalities. The cognitive symptoms were of the same type in all patients, mostly frontal lobe syndrome and memory problems. The neuropsychological involvement was not associated with other kinds of CNS involvement or MRI abnormalities, but accurately reflected HMPAO imaging results.. The results of this study indicate that cognitive evaluation is the most sensitive clinical test to diagnose CNS involvement in patients with SS, and that CNS involvement in SS seems to be more frequent when systematically assessed by neuropsychological tests.

Topics: Adult; Brain; Brain Diseases; Cognition; Female; Humans; Interview, Psychological; Magnetic Resonance Imaging; Memory; Middle Aged; Neuropsychological Tests; Prospective Studies; Psychological Tests; Sjogren's Syndrome; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Involvement of the brain is one of the most important complications of Sjögren's syndrome (SS). However, diagnosis of brain involvement in SS patients is difficult due to the lack of effective imaging methods. In this study, we compared two updated brain imaging modalities, 18F-2-fluoro-2-deoxy-D-glucose (FDG) PET and 99mTc-hexamethyl propyleneamine oxime (HMPAO) SPECT, in SS patients with neuropsychiatric manifestations, to detect glucose metabolism of the brain and regional cerebral blood flow.. Sixteen primary female SS patients with normal brain MRI findings were enrolled in this study.. Technetium-99m-HMPAO SPECT findings were abnormal in 13 (81%) patients. Parietal and temporal lobes were the most common areas of brain involvement. Fluorine-18-FDG PET findings were abnormal in 3 (19%) patients. Temporal lobes were the most common areas of brain involvement.. We conclude that brain HMPAO SPECT has better correlation with clinical manifestations than brain FDG PET or CT/MRI.

Topics: Adult; Brain; Brain Diseases; Cerebrovascular Circulation; Female; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Glucose; Humans; Magnetic Resonance Imaging; Middle Aged; Radiopharmaceuticals; Sensitivity and Specificity; Sjogren's Syndrome; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

Involvement of the brain is one of the most important complications of Behçet's disease (BS). It is difficult to diagnose, however, because of the lack of effective imaging methods.. Thirteen BS patients with neuropsychiatric symptoms or signs [Neuro-Behçet's syndrome (NBS)] were included in this study. We combined two routine brain imaging modalities-brain SPECT with 99mTc-hexamethyl propyleneamine oxime (HMPAO) and brain MRI-with clinical manifestations to diagnose brain involvement.. Technetium-99m-HMPAO brain SPECT findings were abnormal in 100% (13/13) of patients. Brain MRI findings were abnormal in 31% (4/13) of patients. Gray matter was involved more commonly than white matter. In the gray matter, the cerebral cortex was the most commonly involved area and the cerebellum was the least commonly involved area in NBS.. SPECT is a more sensitive and useful tool in detecting brain involvement in NBS patients compared with brain MRI. The combination of HMPAO and MRI is necessary to detect brain lesions in both gray and white matter in NBS.

Topics: Adult; Behcet Syndrome; Brain; Brain Diseases; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neurologic Examination; Radiopharmaceuticals; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Discrepancies have been reported between the findings of Tc-99m HMPAO and Tc-99m ECD brain perfusion SPECT imaging. This study investigated the discrepancies in the accumulation of these tracers using dynamic SPECT to detect the super early phase of distribution. Thirteen patients with luxury perfusion or high flow states were studied with both dynamic and standard SPECT using Tc-99m HMPAO and Tc-99m ECD within 1-3 days. Standard SPECT showed discrepancies in 6 of 13 patients. Patients with meningioma and cerebral thrombosis had increased accumulation of Tc-99m HMPAO and decreased uptake of Tc-99m ECD. Patients with arteriovenous malformation, subarachnoid hemorrhage, and cavernous angioma had decreased accumulation of both tracers, but to different degrees. Dynamic SPECT showed increased or normal accumulation (i.e., essentially no discrepancy) in the first few minutes. However, Tc-99m HMPAO had a longer retention time than Tc-99m ECD in the ensuing 5-10 minutes. Dynamic SPECT revealed a similar accumulation pattern but different washout rates for the two tracers. Tc-99m HMPAO might be a more suitable tracer to detect high flow states or luxury perfusion because the findings on standard SPECT were more in agreement with those of dynamic SPECT using this tracer.

Topics: Adult; Aged; Brain; Brain Diseases; Brain Neoplasms; Cerebrovascular Circulation; Cerebrovascular Disorders; Cysteine; Female; Humans; Hyperemia; Male; Middle Aged; Organotechnetium Compounds; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Neurosarcoidosis with recurrent stroke-like episodes has been reported only rarely in the literature. We repeatedly measured brain magnetic resonance images (MRI), SPECT, and electroencephalograms (EEG) in a 32-year-old male patient with this condition. In the acute stage of the episodes, he showed semi-coma followed by severe dysphasia; left-frontal EEG delta wave activities and left-sided hyperperfusion SPECT were noted. Gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) MRI findings were aggravated diffusely in the convalescent stage of the disease rather than in the acute stage. The EEG and SPECT findings were clearly reflective of an early stage of acute encephalomeningitis caused by the neurosarcoidosis, and thus are more useful than MRI for evaluation of the acute inflammatory process in this condition.

Topics: Adult; Biopsy; Brain Diseases; Cerebrovascular Disorders; Electroencephalography; Humans; Magnetic Resonance Imaging; Male; Radiopharmaceuticals; Recurrence; Sarcoidosis; Technetium Tc 99m Exametazime; Time Factors; Tomography, Emission-Computed, Single-Photon

To evaluate the EEG changes during seizures in children with drug resistant focal epilepsy who demonstrate hypoperfusion at the "seizure focus" interictally, but no perfusion change during the seizure.. Ictal EEG findings of six children with focal epilepsy who demonstrated hypoperfusion on rCBF SPECT after an interictal injection of (99)Tc(m) HMPAO concordant with the seizure focus, but who did not demonstrate rCBF change after an ictal injection (group 1) were reviewed. These were contrasted with the EEG data of six children matched as closely as possible for age, type of epilepsy, and pathology who did show hyperperfusion at the seizure focus on ictal scan when compared with the interictal study (group 2).. The children in group 1 showed slowing of the EEG at the time of the (99)Tc(m) HMPAO injection relative to that seen at the onset of the seizure. Those in group 2 showed rhythmic activity, or sharp waves, or both on EEG at the time of injection. This last change was also seen consistently when the EEG data of a further 13 children who also showed ictal hyperperfusion at the seizure focus were reviewed.. Ictal rCBF does not invariably increase at the seizure focus in patients with drug resistant focal epilepsy.

Topics: Adolescent; Adult; Brain Diseases; Brain Neoplasms; Cerebral Infarction; Child; Cysts; Drug Resistance; Electroencephalography; Epilepsies, Partial; Hippocampus; Humans; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The purpose of this study was to comparatively evaluate the quality of SPECT images for the mapping of rCBF using three tracers, 123I-IMP, 99mTc-HMPAO and 99mTc-ECD. We performed three SPECT studies on seven patients with various cerebral diseases under the same conditions. An effect of Lassen's correction on SPECT images obtained by HMPAO was also evaluated. The same irregular regions of interest were placed on the four transaxial SPECT images. To quantitatively evaluate the pattern of tracer uptake and image contrast, the uptake ratio, regional count/mean count of the cerebrum, and its coefficient variations (CV) were defined, respectively. The order of the value of CV was HMPAO with correction > IMP > ECD > HMPAO without correction. HMPAO with correction showed the best image contrast, but HMPAO without correction was the worst. Uptake ratios of ECD and HMPAO with correction were decreased in the brain stem and thalamus in comparison with those of IMP. Both uptake ratios of ECD and HMPAO without correction were increased in the occipital cortex. IMP provides high quality SPECT images. Images obtained by HMPAO should be modified by Lassen's correction to increase image contrast. ECD or HMPAO should not be used to evaluate patients with spinocerebellar degeneration.

Topics: Aged; Amphetamines; Brain Diseases; Cerebrovascular Circulation; Cysteine; Female; Humans; Iodine Radioisotopes; Iofetamine; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

To explore the use of 99technetiumm-hexamethyl propylene amine oxime single photon computed tomography (HMPAO-SPECT) of the brain as a means of detecting nervous tissue damage in divers and to determine if there is any correlation between brain image and a diver's history of diving or decompression illness (DCI).. 28 commercial divers with a history of DCI, 26 divers with no history of DCI, and 19 non-diving controls were examined with brain HMPAO-SPECT. Results were classified by observer assessment as normal (I) or as a pattern variants (II-V). The brain images of a subgroup of these divers (n = 44) and the controls (n = 17) were further analysed with a first order texture analysis technique based on a grey level histogram.. 15 of 54 commercial divers (28%) were visually assessed as having HMPAO-SPECT images outside normal limits compared with 15.8% in appropriately identified non-diver control subjects. 18% of divers with a history of DCI were classified as having a pattern different from the normal image compared with 38% with no history of DCI. No association was established between the presence of a pattern variant from the normal image and history of DCI, diving, or other previous possible neurological insult. On texture analysis of the brain images, divers had a significantly lower mean grey level (MGL) than non-divers. Divers with a history of DCI (n = 22) had a significantly lower MGL when compared with divers with no history of DCI (n = 22). Divers with > 14 years professional diving or > 100 decompression days a year had a significantly lower MGL value.. Observer assessment of HMPAO-SPECT brain images can lead to disparity in results. Texture analysis of the brain images supplies both an objective and consistent method of measurement. A significant correlation was found between a low measure of MGL and a history of DCI. There was also an indication that diving itself had an effect on texture measurement, implying that it had caused subclinical nervous tissue damage.

Topics: Adult; Brain Diseases; Case-Control Studies; Decompression Sickness; Diving; Humans; Occupational Diseases; Organotechnetium Compounds; Oximes; Prevalence; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Cerebral sparganosis is an extremely rare intracranial parasitic infectious disease. We report findings of 99mTc-HMPAO cerebral perfusion SPECT in a case with cerebral sparganosis. SPECT revealed an irregularly shaped area with markedly increased 99mTc-HMPAO uptake in the parasitic infectious region of the cerebrum. Both white and gray matter was involved, the white matter involved predominantly. Decreased perfusion to the right cerebellum, suggesting cross cerebellar diaschisis, was also demonstrated. This article illustrates that cerebral sparganosis is one of the causes of increased 99mTc-HMPAO uptake in the cerebrum and should be considered clinically if present.

Topics: Aged; Brain Diseases; Humans; Male; Organotechnetium Compounds; Oximes; Sparganosis; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

To examine neurological, neuropsychological, psychiatric, and cerebral perfusion correlates of leukoaraiosis in Alzheimer's disease.. A consecutive series of patients with probable Alzheimer's disease was assessed with a comprehensive neuropsychological battery, a structured psychiatric evaluation, the unified Parkinson's disease rating scale, MRI, and single photon emission computed tomography with technetium 99m hexamethylpropyleneamine oxime (HMPAO) and regional cerebral perfusion measurements.. Patients with Alzheimer's disease and leukoaraiosis were significantly more apathetic and had significantly more extrapyramidal signs than patients with Alzheimer's disease without leukoaraiosis. Patients with Alzheimer's disease with leukoaraiosis also had significantly lower bilateral perfusion in the basal ganglia, thalamus, and frontal lobes than patients with Alzheimer's disease without leukoaraiosis. On the other hand, there were no significant differences between groups in age, duration of illness, depression scores, severity of delusions, or deficits on specific neuropsychological tasks.. Leukoaraiosis in Alzheimer's disease may produce significant basal ganglia, and thalamic and frontal lobe dysfunction, which may be associated with more severe apathy and extrapyramidal signs.

Topics: Aged; Alzheimer Disease; Analysis of Variance; Basal Ganglia Diseases; Brain; Brain Diseases; Cerebrovascular Circulation; Female; Humans; Magnetic Resonance Imaging; Male; Neurologic Examination; Neuropsychological Tests; Organotechnetium Compounds; Oximes; Psychiatric Status Rating Scales; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The authors studied 33 normal patients who ranged in age from 8 to 71 years to establish a normative data base for young-age, middle-age, and older-age subjects using a computer automated semi-quantitative cortical annular region of interest (ROI) method. The data were grouped to obtain a "young age-range" normative data base of mean age +/- 1 S.D. = 13.1 +/- 4.8 years (seven subjects with an age range of 6 to 20 years); a "middle age-range" normative data base of mean age +/- 1 S.D. = 39 +/- 2.7 years (12 subjects with an age range of 35 to 43 years); and an "older age-range" normative data base of mean age +/- 1 S.D. = 59.7 +/- 5.8 years (14 subjects with an age range of 55 to 71 years). Normative values were obtained for brain level parallel to and positioned at 3.5, 5.5, and 7.5 cm above the canthomeatal (CM) line. The results show that the average global rCBF indices (defined as cortical/cerebellar ratios) for the young age-range group were 0.98, 0.99, 1.07; middle age-range group were 0.84, 0.86, and 0.88; and older age-range group were 0.86, 0.87 and 0.87 for CM + 3.5 cm, CM + 5.5 cm, and CM + 7.5 cm, respectively. In routine clinical studies, on more then 2,000 Tc-99m HMPAO brain SPECT scans, the authors have employed this semi-quantitative cortical circumferential normalization method of analysis to accurately calculate indices representing cortical blood flow values. This method also allows efficient comparison of individual patient values to age-range matched normal control groups to assist in disease diagnosis.

Topics: Adolescent; Adult; Aged; Aging; Alzheimer Disease; Brain Diseases; Case-Control Studies; Cerebellum; Cerebral Cortex; Cerebrovascular Circulation; Child; Corpus Callosum; Frontal Lobe; Gyrus Cinguli; Humans; Image Processing, Computer-Assisted; Middle Aged; Parietal Lobe; Radiopharmaceuticals; Reference Values; Reproducibility of Results; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Single photon emission computed tomography (SPECT) with [99mTc] HMPAO was performed sequentially every week in 4 patients with systemic lupus erythematosus (SLE), from the acute phase of neurologic involvement until normal cerebral blood flow (CBF) was detected by the scan. SPECT accurately reflects central nervous system (CNS) abnormalities in patients with SLE and correlates with subsequent improvement. Correlated with the patients' rapid clinical improvement, the brain SPECT blood flow scan demonstrated homogeneous distribution in 1 to 9 weeks. In these four patients, the defect in CBF could be reversed by optimal treatment. Brain SPECT blood flow scan may be used as a biologic marker of pathologic activity in the brain of patients with SLE.

Topics: Adolescent; Anti-Inflammatory Agents; Brain; Brain Diseases; Cerebral Cortex; Child; Female; Follow-Up Studies; Humans; Lupus Erythematosus, Systemic; Magnetic Resonance Imaging; Methylprednisolone; Neurologic Examination; Prednisolone; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

High-flow interstitial infusion into the brain, which uses bulk fluid flow to achieve a relatively homogeneous drug distribution in the extracellular space of the brain, has the potential to perfuse large volumes of brain. The authors report reproducible long-term delivery of 111In-diethylenetriamine pentaacetic acid-apotransferrin (111In-DTPA-Tf) (molecular mass 81 kD) to Macaca mulatta brain and monitoring with single-photon emission computerized tomography (SPECT). The 111In-DTPA-Tf was infused at 1.9 microl/minute over 87 hours into the frontal portion of the centrum semiovale using a telemetry-controlled, fully implanted pump. On Days 1, 3, 4, 8, 11, and 15 after beginning the infusion, planar and SPECT scans of 111In-DTPA-Tf were obtained. Spread of protein in the brain ranged from 2 to 3 cm and infusion volumes ranged from 3.9 to 6.7 cm3. Perfusion of over one-third of the white matter of the infused hemisphere was achieved. From brain SPECT images of (99m)Tc-hexamethylpropyleneamine oxime, which was administered intravenously before each 111In scan, the authors also found that blood perfusion in the infused region was reduced by less than 5% relative to corresponding noninfused regions. Histological examination at 30 days revealed only mild gliosis limited to the area immediately surrounding the needle tract. These findings indicate that long-term interstitial brain infusion is effective for the delivery of drugs on a multicentimeter scale in the primate brain. The results also indicate that it should be possible to perfuse targeted regions of the brain for extended intervals to investigate the potential utility of neurotrophic factors, antitumor agents, and other materials for the treatment of central nervous system disorders.

Topics: Animals; Antineoplastic Agents; Apoproteins; Autoradiography; Brain; Brain Diseases; Brain Neoplasms; Cerebral Cortex; Cerebrovascular Circulation; Extracellular Space; Gliosis; Indium Radioisotopes; Infusion Pumps, Implantable; Injections, Intravenous; Iron Chelating Agents; Macaca mulatta; Metabolic Clearance Rate; Needles; Neurons; Organotechnetium Compounds; Oximes; Pentetic Acid; Radiopharmaceuticals; Rheology; Technetium Tc 99m Exametazime; Telemetry; Tomography, Emission-Computed, Single-Photon; Transferrin

We studied risk factors for cerebral vascular disease (blood pressure and hypertension, factor VIIc, factor VIIIc, fibrinogen), indicators of atherosclerosis (intima-media thickness and plaques in the carotid artery) and cerebral white matter lesions in relation to regional cerebral blood flow (rCBF) in 60 persons (aged 65-85 years) recruited from a population-based study. rCBF was assessed with single-photon emission tomography using technetium-99m d, l-hexamethylpropylene amine oxime (99mTc-HMPAO). Statistical analysis was performed with multiple linear regression with adjustment for age, sex and ventricle-to-brain ratio. A significant positive association was found between systolic and diastolic blood pressure and temporo-parietal rCBF. In analysis with quartiles of the distribution, we found a threshold effect for the relation of low diastolic blood pressure (3.2 g/l) and low rCBF. Increased atherosclerosis was related to low rCBF in all cortical regions, but these associations were not significant. No consistent relation was observed between severity of cerebral white matter lesions and rCBF. Our results may have implications for blood pressure control in the elderly population.

Topics: Aged; Aged, 80 and over; Antigens; Brain; Brain Diseases; Carotid Arteries; Cerebrovascular Circulation; Factor VII; Factor VIII; Female; Fibrinogen; Humans; Hypertension; Intracranial Arteriosclerosis; Linear Models; Magnetic Resonance Imaging; Male; Organotechnetium Compounds; Oximes; Risk Factors; Sampling Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Ultrasonography

A patient with neuro-Behçet's disease was studied with both Tc-99m-HMPAO and Tc-99m-ECD brain perfusion SPECT during the same time period. In Tc-99m-HMPAO SPECT, focal high uptake was observed in the left basal ganglia where MRI depicted abnormal signal intensity. Conversely, Tc-99m-ECD SPECT did not show corresponding high uptake, but demonstrated rather low uptake in contrast to the Tc-99m-HMPAO SPECT. This case suggests that Tc-99m-HMPAO and Tc-99m-ECD may show discordant distribution in inflammatory brain disease such as neuro-Behçet's disease.

Topics: Adult; Behcet Syndrome; Brain; Brain Diseases; Cysteine; Female; Humans; Magnetic Resonance Imaging; Organotechnetium Compounds; Oximes; Reproducibility of Results; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

This study, performed in 94 consecutive patients referred for evaluation, demonstrates the clinical utility of cerebral SPECT imaging. In a significant percentage of patients (47%), the additional information provided by SPECT resulted in an alteration in clinical management. Long-term follow-up will be necessary to determine the effect of these management decisions on patient outcome.

Topics: Brain; Brain Diseases; Case-Control Studies; Cerebrovascular Disorders; Craniocerebral Trauma; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Several neuroimaging techniques that supplement electrophysiologic methods of evaluating pediatric patients with localization-related epilepsies before surgery assess both structural and functional abnormalities. For example, single photon emission computed tomography (SPECT) with technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) has been used to demonstrate abnormal cerebral perfusion. States of cerebral perfusion during the interictal and immediate postictal periods have been reported to correlate with epileptiform foci identified by electroencephalogram (EEG). Between January 1987 and March 1993, we studied 55 pediatric patients with intractable seizures with prolonged video EEG telemetry in the epilepsy monitoring unit, followed by computed tomography, magnetic resonance imaging, and SPECT, before surgery to determine whether SPECT studies with 99mTc-HMPAO improved the accuracy of locating the epileptic focus. Interictal SPECT was performed on all patients, and immediate postictal SPECT (within 10 minutes after seizure ended) on 17 patients monitored in the epilepsy monitoring unit. In 15 (88%) of the 17, the combination of interictal and postictal SPECT studies yielded results corresponding to the EEG abnormality, a result significantly better than that obtained from interictal studies alone: 21 (55%) of 38 (chi 2 = 5.647, P = .0175). SPECT scans showed localized abnormal perfusion in the ipsilateral temporal lobe in all six patients with mesial temporal sclerosis, but precise results were not obtained in cases of dual pathology and neuronal migration disorders. Depiction of cerebral perfusion by interictal and immediate postictal SPECT studies can lead to greater accuracy in the localization of epileptic foci.

Topics: Adolescent; Brain Diseases; Brain Mapping; Child; Child, Preschool; Dominance, Cerebral; Electroencephalography; Epilepsy; Female; Humans; Male; Monitoring, Physiologic; Organotechnetium Compounds; Oximes; Regional Blood Flow; Retrospective Studies; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, Emission-Computed, Single-Photon; Video Recording

Topics: Adult; Brain Diseases; Cerebral Cortex; Frontal Lobe; Humans; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The potential clinical utility of SPECT (Single Photon Emission Computed Tomography) brain imaging to clarifying certain diagnostic dilemmas faced by clinical psychiatrists is considered generally and is illustrated by several case vignettes. Three case histories consider dementia vs depressive pseudodementia, two the possibility of a cerebral vasculitis in patients with auto-immune conditions, and two whether the patient had a "type" of depression likely to benefit from a course of ECT. Published studies reviewing the utility of SPECT in dementia, depression, depressive "pseudodementia" and cerebral lupus are considered. It is suggested that SPECT is an important investigatory technique providing additional information that may assist some diagnostic decisions, while its utility in assisting other clinical decisions awaits clarification.

Topics: Adult; Aged; Brain; Brain Diseases; Dementia; Depressive Disorder; Diagnosis, Differential; Electroconvulsive Therapy; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Scintigraphy with 111In (indium-111)-oxine or 99mTechnetium-hexamethylpropyleneamine oxime (99mTc-HMPAO) labeled leukocytes has been used to differentiate brain abscess from brain tumor. However, there are false positive or false negative results from planar scintigraphic images. So a more specific and sensitive scintigraphic technique needs to be developed.. Planar and single photon emission computed tomography (SPECT) images were obtained and reviewed in 14 patients with intracerebral ring-enhancing lesions on computed tomography (CT) or magnetic resonance imaging (MRI). In all patients, diagnosis was confirmed by histopathologic examination. The effect of steroids or antibiotics on scintigraphic finding was examined.. Abscess was confirmed in six patients, tumor in six, tuberculoma and cysticercosis in one each, respectively. In all the patients with abscess, SPECT showed increased focal activity irrespective of steroid or antibiotic therapy. Increased radioactivity, which could not be detected on planar images, could be identified in two patients with abscess. In three of the six patients with tumor, radiolabeled leukocytes did not accumulate in the tumor. In the other three patients with tumor, SPECT showed focally increased activity that was less intense than the activity shown in the patients with abscess.. 99mTc-HMPAO labeled leukocyte SPECT is useful for the differential diagnosis of intracerebral ring-enhancing lesions, and the use of steroids or antibiotics does not influence the sensitivity of SPECT. Diagnostic sensitivity of scintigraphy with labeled leukocytes could be improved by SPECT in addition to planar image.

Topics: Adult; Aged; Brain Abscess; Brain Diseases; Brain Neoplasms; Cysticercosis; Female; Humans; Indium Radioisotopes; Leukocytes; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tuberculoma, Intracranial

We describe a reference device that provides accurate correlation between anatomic and functional brain images. The reference device, which generates fiduciary reference points on sequential scan planes, is positioned adjacent to the canthomeatal line of the subject and held in place by a glasses-like framework anchored to the external auditory meatus. The reference system was tested on 17 subjects undergoing 99mTc hexamethylpropylene amine oxime ([99mTc]HMPAO) brain single-photon emission computed tomography (SPECT) and cranial computed tomography (CT) scans. The centers of the caudate nuclei, thalami, brain stem, and cerebellar vermis were identified independently on CT and SPECT. The average difference +/- 1 SD between structure locations (x, y, and z) on SPECT and CT were calculated as 1.86 +/- 1.5, 2.16 +/- 1.4, and 1.83 +/- 1.9 mm, respectively. The clinical application of the method is showed by coregistration of images from SPECT to MRI. An example of sequential [99mTc]HMPAO brain SPECT scan sections precisely coregistered with MRI scan sections oriented parallel to and sequentially above the canthomeatal line illustrates the correlation between regional cerebral blood flow (rCBF) tracer activity on SPECT and normal anatomic structures. Test-retest activation paradigms in brain SPECT requires precise SPECT-to-SPECT image coregistration to evaluate changes in rCBF during activation. Precisely coregistered rest, 48-hour repeat rest [99mTc]HMPAO SPECT studies are shown to illustrate the normal intrasubject variability of tracer uptake. An example of the usefulness of image coregistration for evaluation of viable residual brain tumor and its application to tumor biopsy is presented. An example of developmental abnormalities identified by [99mTc]HMPAO brain SPECT is illustrated by a case of autistic disorder. An example of image coregistration in stroke and evaluation of cerebrovascular disease with Diamox (Lederle Laboratory Division, Pearl River, NY) cerebrovasculature stress testing is presented. The usefulness in epilepsy using a protocol whereby the tracer is injected during the ictal phase of seizure is presented. We conclude that the reference system provides an accurate, rapid, and noninvasive patient-specific method for correlating brain structure with brain function.

Topics: Adolescent; Adult; Brain; Brain Diseases; Brain Mapping; Cerebrovascular Circulation; Child; Female; Humans; Magnetic Resonance Imaging; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Sixteen patients with primary brain tumours were examined on average eight years after treatment with surgery or whole brain irradiation using standard clinical assessment, CT, a neuropsychological test battery, and single photon emission CT (SPECT) with 99mTc-exametazime. Seventeen lesions were discovered on inspection of SPECT images, 11 with x-ray CT. Quantitative assessment of tracer uptake compared with 16 matched healthy volunteers was consistent with the presence of lesions. Measurement of uptake in brain regions of the hemisphere not containing the primary tumour still showed significant reductions in patients. This may be due to remote direct effects of the tumour or, more likely, to the whole brain irradiation received. Psychometric performance on most tests was significantly impaired in the patient group and was correlated with abnormalities of tracer uptake to relevant brain regions.

Topics: Adult; Aftercare; Brain Diseases; Brain Neoplasms; Case-Control Studies; Cranial Irradiation; Craniotomy; Female; Humans; Male; Matched-Pair Analysis; Middle Aged; Neuropsychological Tests; Organotechnetium Compounds; Oximes; Psychometrics; Psychomotor Performance; Survivors; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

In this study we used a single photon emission computed tomography technique (SPECT) with radiolabelled 99mTcHMPAO to assess cerebral perfusion in newborn infants with documented cerebral lesions and to determine to what extent brain SPECT might be useful in the neonatal period. A total of 15 newborn infants with the following cerebral pathologies were enrolled: severe parietal bilateral periventricular leucomalacia (PVL, n = 6); moderate parietal bilateral PVL (n = 2); intraventricular haemorrhage grade II with unilateral parietal parenchymal extension (IHV + PE, n = 3); cerebral infarction (CI, n = 2) in the zone of middle cerebral artery; and post-haemorrhagic hydrocephalus (n = 2). Follow-up was available in all infants. Alterations in cerebral perfusion were seen in only 12 of 15 infants and at the location of severe PVL, PE and CI. We have noted that the regions of diminished perfusion extended beyond the apparent extent of cerebral pathology delineated by ultrasound or magnetic resonance imaging. Markedly diminished perfusion was seen in 1 infant with hydrocephalus, which recovered following placement of ventriculo-peritoneal shunt. Regarding outcome, SPECT data failed to provide additional information than that of neuroradiological investigations. We conclude that the use of SPECT, under these conditions, to assess alteration of cerebral perfusion in the neonatal period will not provide any additional information than that of neuroradiological investigations.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Humans; Infant, Newborn; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

To report the development and validation of a technique of dual tracer single-photon emission CT brain imaging using technetium-99m hexamethylpropyleneamine oxime and iodine-123 iodoamphetamine agents and the application of this technique in patients with a variety of diagnoses.. Contamination between the two isotopes' energy windows was calculated by opening both energy windows while scanning a group of patients using a single isotope. To compare uniformity of I-123 down-scatter, Tc-99m studies were performed both before and after the administration of I-123 in five of 24 dual studies. The 24 patients studied with the dual-isotope technique were evaluated during acetazolamide testing, trial balloon occlusion, or embolization of an arteriovenous malformation.. In a dual acquisition, average count contamination of an I-123 study by Tc-99m was less than 1% of the total I-123 counts, and contamination of a Tc-99m study by I-123 was approximately 12% of the total Tc-99m counts. Tc-99m studies performed both before and after the administration of I-123 demonstrated that contaminating counts do not adversely affect scan interpretation. Dual-tracer scans were completed in all 24 patients, 10 of whom showed changes after intervention.. Dual-tracer single-photon emission CT brain scans of adequate diagnostic quality are possible using Tc-99m and I-123.

Topics: Acetazolamide; Adolescent; Adult; Aged; Amphetamines; Brain; Brain Diseases; Cerebrovascular Disorders; Female; Humans; Iodine Radioisotopes; Male; Middle Aged; Models, Structural; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

We performed initial and follow-up regional cerebral blood flow (rCBF) studies using 99mTc-hexamethylpropyleneamine oxime (HMPAO) SPECT on a patient with manganese-induced central nervous system (CNS) neurotoxicity.. The patient had a history of long-term exposure to manganese at the time of the first scan, while the follow-up scan was performed 9 mo after removal from the toxic environment. The patient's serum level of manganese was five- to tenfold greater than normal at the time of the initial rCBF brain SPECT scan.. The rCBF brain SPECT scan demonstrated significantly decreased rCBF in the right caudate nucleus and both thalami. A MRI scan obtained at the same time was normal. The follow-up rCBF brain SPECT scan was normal.. This report supports the utilization of functional rCBF brain SPECT imaging to provide objective evidence of a function CNS abnormality due to neurotoxicity at an early clinical stage. Our results emphasize that rCBF brain SPECT may provide a confirmational test to support the diagnosis of neurotoxicity in the appropriate clinical setting.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Female; Humans; Manganese Poisoning; Middle Aged; Organotechnetium Compounds; Oximes; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Positron emission tomography (PET) and single photon emission computed tomography (SPECT) use advanced computer image construction techniques to illustrate regional cerebral function, metabolism, and chemistry. Although the resolution of PET is higher than that of SPECT, and the technical development of SPECT has lagged behind that of PET, SPECT has recently enjoyed increasingly widespread use, particularly because its costs and technology are within the reach of all clinical nuclear medicine facilities. SPECT imaging agents have greater half-lives than those used with PET, thereby permitting longer and more detailed neurochemistry study than is possible with PET. The research value of both methods has unique potential compared with computed tomography (CT) and magnetic resonance imaging (MRI), which traditionally have provided a static image of the brain's structure or anatomy.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Humans; Iodine Radioisotopes; Magnetic Resonance Imaging; Mental Disorders; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Brain perfusion SPECT studies of 123I-IMP and 99mTc-HMPAO were performed in 10 patients with various brain disorders and the difference in the distribution of 123I-IMP and 99mTc-HMPAO in the cortices and striatum was compared with the cerebral blood flow by 15O-PET method. The ratios of the radioactivity in 14 ROIs of the cortices, striatum and cerebellum to that of the reference region or the right frontal cortex were compared among the 3 studies. The coefficient variance between 123I-IMP and PET was 0.71 and that between 99mTc-HMPAO and PET was 0.74 in the regions excluding the striatum. The striatal activity ratio in 123I-IMP was slightly less than those in 99mTc-HMPAO and PET which were close to each other. The visual activity in the striatum in 123I-IMP was also slightly less than those in 99mTc-HMPAO and PET. All the striatal lesions of decreased perfusion diagnosed by PET were observed in 123I-IMP, however 2 lesions were missed in 99mTc-HMPAO. This seems to be relevant to the difference in the distribution of 123I-IMP and 99mTc-HMPAO.

Topics: Adolescent; Adult; Aged; Amphetamines; Brain Diseases; Cerebral Cortex; Cerebrovascular Circulation; Corpus Striatum; Female; Humans; Iodine Radioisotopes; Iofetamine; Male; Middle Aged; Organotechnetium Compounds; Oximes; Oxygen Radioisotopes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

Alterations in regional cerebral blood-flow, as determined by single-photon emission computed tomography (SPECT) using technetium [99mTc] hexamethyl propylenamine oxime, were studied in two children presenting with alternating hemiplegia of childhood. Both experienced hemiplegic episodes several times per month, despite marked improvement on flunarizine therapy. SPECT images of both patients revealed focal areas of decreased uptake of the radiotracer, representing impaired regional cerebral blood-flow during, as well as between, seizures. The interictal finding of localized areas of reduced tracer uptake suggest that long-lasting hypoperfusion could be the pathophysiological mechanism by which the slowly resolving hemiplegia, and ultimately the permanent multifocal neurological deficits, are produced.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Child, Preschool; Female; Flunarizine; Functional Laterality; Hemiplegia; Humans; Intellectual Disability; Language Disorders; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

To determine the prevalence of central nervous system damage due to ethanol, we evaluated 40 asymptomatic chronic alcoholics and 20 age-matched controls. Studies included neuropsychological testing, brain 99mTc-HMPAO SPECT, and morphometric analysis by CT scan. In the qualitative analysis, 30 of the 40 alcoholics showed hypoperfused areas on SPECT scan. In the semiquantitative analysis, alcoholics exhibited significant reduction in regional cerebral blood flow (rCBF) ratio of all brain lobes compared to controls (p < 0.001). The rCBF ratio was mainly reduced in frontal lobes (65%). Only 11 alcoholics showed significant frontal lobe atrophy in the morphometric analysis; most also had abnormalities on SPECT scan. Alcoholics exhibited significant impairment of frontal tasks and visuospatial skills. Frontal test impairment was independently related to both frontal atrophy and hypoperfusion. In a group of ten alcoholics in whom another SPECT scan was performed after 2 mo of ethanol abstinence, rCBF ratio of the frontal lobes normalized in eight, without frontal atrophy. In patients without frontal atrophy, reduced rCBF ratio of the anterior portion of the frontal lobes correlated negatively with frontal test results (r = -0.6535, p < 0.001). A significant negative correlation between cerebral perfusion and the amount of ethanol consumed in the month prior to study was observed (r = -0.6289, p < 0.001). In conclusion, asymptomatic chronic alcoholics frequently showed reversible frontal lobe hypoperfusion, which is related to recent ethanol intake, reflects brain function impairment and is independent of brain atrophy.

Topics: Adult; Alcoholism; Atrophy; Brain; Brain Diseases; Cerebrovascular Circulation; Frontal Lobe; Humans; Male; Neuropsychological Tests; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

We evaluated regional cerebral blood flow with technetium 99mTc hexamethylpropyleneamineoxime single photon emission computed tomography (SPECT) in 20 children and adolescents with neurologic dysfunction of varied etiology and abnormal electroencephalograms (EEGs). All patients were also examined with computed tomography (CT) and magnetic resonance imaging (MRI). Abnormal perfusion was found in 17 (85%) of 20 SPECT scans. Abnormal CT or MRI scans were noted in nine (45%) and in 10 (50%) of 20 cases, respectively. In eight (73%) of 11 cases with normal CT scans and in seven (70%) of 10 with normal MRI scans, the SPECT scan was abnormal. Abnormal regional cerebral blood flow on SPECT scans correlated better with EEG abnormalities than with neurologic examination or CT or MRI scan findings. We conclude that in children and adolescents with a spectrum of neurologic diseases and abnormal EEGs, abnormalities of brain structure or function are more likely to be documented by SPECT than by CT or MRI scans. SPECT findings correlate well with the location and type of EEG abnormality.

Topics: Adolescent; Adult; Brain Diseases; Cerebrovascular Circulation; Child; Child, Preschool; Electroencephalography; Female; Humans; Infant; Intellectual Disability; Magnetic Resonance Imaging; Male; Nervous System Diseases; Organotechnetium Compounds; Oximes; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

We used single photon emission computed tomography (SPECT) with technetium-99m hexamethylpropylene amine oxime (99mTc-HM-PAO) in 14 studies on 6 patients with delayed neurologic sequelae from carbon monoxide (CO) poisoning to determine whether any changes in cerebral blood flow could be correlated with clinical or computed tomographic evidence of delayed deficits. Among the six initial CT brain scans, two showed low density of both basal ganglia and two showed decreased density of the cerebral white matter. There was no correlation between the clinical outcome and the findings of the follow-up CT brain scans. Of the two SPECTS with 99mTc-HM-PAO performed during acute anoxic insult, one showed focal hypoperfusion which appeared 20 days prior to the onset of delayed neurologic sequelae after CO poisoning. Seven SPECTs in the six patients performing the delayed phase showed diffuse patched patterns of hypoperfusion which improved on follow-up images. There was good correlation between the clinical outcome and the findings of the 99mTc-HM-PAO SPECT. In preliminary conclusion, 9Tc-HM-PAO brain SPECT can be used for predicting or evaluating the outcome of delayed neurologic sequelae after CO poisoning. Cerebral vascular changes may be the possible cause of hypoperfusion in patients with CO poisoning.

Topics: Adult; Aged; Brain Diseases; Carbon Monoxide Poisoning; Female; Humans; Middle Aged; Organotechnetium Compounds; Oximes; Predictive Value of Tests; Technetium Tc 99m Exametazime; Time Factors; Tomography, Emission-Computed, Single-Photon

For the purpose of facilitating anatomical localization in interpretation of 99Tcm-hexamethylpropyleneamine oxime (HMPAO) brain single photon emission tomographic (SPECT) scans, a stereotaxic proportional grid system was applied in the form of an interactive computer program. This method takes advantage of a rotating gamma camera system which permits planar scout imaging for the determination of anatomical reference lines, and standardization of tomographic slices for brain size. Using measurements made on a lateral planar HMPAO image, proportional grids were constructed onto standardized transaxial images. This method was implemented for 33 clinical HMPAO SPECT studies. It required less than 15 min of an operator's time. This simple and practical neuroanatomical localization technique can be instrumental as an aid to the interpretation of routine clinical HMPAO SPECT images.

Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Brain; Brain Diseases; Brain Injuries; Dementia; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Software; Stereotaxic Techniques; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The clinical, neuropsychological, and cerebral blood flow characteristics of eight patients with frontal lobe degeneration (FLD) were studied. Social withdrawal and behavioral disinhibition were the earliest and most common clinical presentations, and psychiatric symptoms typically preceded the onset of dementia by several years. Neuropsychological testing showed selective impairment of frontal and memory tasks with relative sparing of attention, language, and visuospatial skills. Single-photon emission computerized tomography demonstrated frontal and temporal hypoperfusion with relative sparing of parietal and occipital blood flow. Previous studies suggest that the neuropathologic findings in patients with FLD are varied; some demonstrate frontal gliosis, neuronal loss, and Pick bodies while others show only gliosis and neuronal loss.

Topics: Aged; Brain Diseases; Cerebrovascular Circulation; Dementia; Female; Frontal Lobe; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

CT scan in a 52-year-old woman, admitted because of grand mal seizure, showed striopallidodentate calcifications due to postoperative hypoparathyroidism. This patient report stresses the possibility of cortical metabolic involvement in this disorder, as shown on Tc-99m HMPAO brain SPECT, despite the absence of cognitive defects.

Topics: Brain; Brain Diseases; Calcinosis; Epilepsy, Tonic-Clonic; Female; Humans; Hypoparathyroidism; Middle Aged; Organotechnetium Compounds; Oximes; Postoperative Complications; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Cerebral blood flow (CBF) was evaluated by gamma camera 99mTc-HMPAO SPECT in 11 patients with AIDS-related neurotoxoplasmosis and correlated with neurological findings and the results of CT and MRI. Evident CBF abnormalities were observed in all patients with involvement of at least two cerebral lobes. In 10 patients the abnormalities were bilateral and in 8 patients basal ganglia were involved; no specific hypoperfusion pattern was however evident. Focal lesions were found in 7 patients by CT (sensitivity: 63.6%) and in 10 patients by MRI (sensitivity: 90.9%). It may be concluded that neurotoxoplasmosis in AIDS patients is associated with a high prevalence of focal cortical and subcortical hypoperfusion but that the scintigraphic findings are not specific; that HMPAO SPECT may show focal hypoperfusion in patients with normal CT studies and/or non-focal MRI abnormalities; that the hypoperfusion may be more extensive than the corresponding MRI lesion(s) and that it may be present even in areas with normal MRI signals; and that more experience and longitudinal studies are needed to assess the possible impact of HMPAO SPECT on follow-up and therapy monitoring.

Topics: Acquired Immunodeficiency Syndrome; Adult; Brain Diseases; Cerebrovascular Circulation; Female; Humans; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Toxoplasmosis

Single-photon emission computed tomography (SPECT) of the brain using hexamethyl propylene amine oxime (HMPAO) was performed in a 37-year-old patient suffering from mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). Reduced blood flow was observed bilaterally in the parieto-occipital regions (resembling Alzheimer type dementia) and in the right parietal lobe.

Topics: Acidosis, Lactic; Adult; Alzheimer Disease; Brain Diseases; Cerebrovascular Disorders; Diagnosis, Differential; Humans; Male; Mitochondria, Muscle; Organotechnetium Compounds; Oximes; Syndrome; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

We performed single photon emission computed tomography (SPECT) and cerebral CT-scans in nine patients with hereditary cerebral amyloid angiopathy. CT-scans showed 23 focal hypodense lesions, 13 of which were visible on SPECT as a CBF-defect. One patient showed a CBF-defect on SPECT without CT-scan lesion and had a cerebral hemorrhage three months later in that particular region. In two additional patients, who were 50% at risk for this autosomal dominant disease, CBF-defects on SPECT, but no cortical lesions on CT-scan were found. CT-scans may be more sensitive than SPECT to detect chronic lesions caused by cerebral hemorrhages, but another possibility is that hemorrhages do not always lead to persistent CBF-defects. SPECT can show the effect of amyloid deposits on CBF before the angiopathy causes clinical symptoms.

Topics: Amyloidosis; Brain Diseases; Cerebral Hemorrhage; Cerebrovascular Circulation; Cerebrovascular Disorders; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Single-Blind Method; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

The purpose of the presented study was to determine the diagnostic value of correlated EEG and SPECT findings in patients with CNS-manifestations of AIDS. Ten HIV 1 infected patients had been examined. Diagnoses: meningitis (2 x), lymphoma (2 x), necrotizing encephalitis (1 x), toxoplasmosis (7 x) (Some patients had more than one diagnosis). Unenhanced and Gd-DTPA enhanced MR, 99mTc-HM-PAO SPECT and clinical EEG were compared. In 9/10 patients MR demonstrated intracranial lesions. In one patient with necrotizing encephalitis (not detected by MR), SPECT revealed an inhomogeneous cerebral perfusion. Only lymphoma was hyperperfused. Toxoplasmic lesions-when detectable by SPECT-were hypoperfused. Reduced rCBF was also seen in brain regions not affected directly, but functionally associated to altered areas. EEG revealed diffuse signs such as slowing in patients with brain atrophy, but also in those patients with lesions of basal ganglia and thalamus. Focal signs in the EEG were in concordance with imaging findings in only 2/10 patients. In 4/10 patients foci even adjacent to the cortex - as shown by MR - remained undetected by EEG. One patient with an active toxoplasmosis had sharp waves over the affected region. The parallel application of the three methods as suggested in this paper appears useful not only for scientific purposes. In most cases, this procedure provides relevant diagnostic information. It is recommended for AIDS-patients with CNS manifestations of unknown etiology.

Topics: Acquired Immunodeficiency Syndrome; Adult; Brain; Brain Diseases; Brain Neoplasms; Electroencephalography; Encephalitis; HIV-1; Humans; Lymphoma; Magnetic Resonance Imaging; Male; Meningitis; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Toxoplasmosis

Topics: Brain; Brain Diseases; Dementia; Humans; Huntington Disease; Organotechnetium Compounds; Oximes; Parkinson Disease; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

A method for the relative quantification of 99mTc-HM-PAO distribution in brain SPECT is described. The method, applied in 12 normal volunteers and 150 patients suffering from different cerebral diseases, uses circumferential profiles to quantify the relative radionuclide distribution in the brain tomograms as an angular function with the origin at the center of the brain slice. Abnormal 99mTc-HM-PAO distribution is evaluated by comparing the count content of symmetrical selected parts of the profile curve and comparing each patient's profile with the corresponding limits of normal ones, determined from the pooled profiles of 12 normal subjects. This computerized method allows an accurate, reproducible and objective assessment of the relative HM-PAO distribution in the brain.

Topics: Adult; Aged; Brain Diseases; Cerebrovascular Circulation; Humans; Middle Aged; Organometallic Compounds; Oximes; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

A recently developed 99mTc radiocompound, hexamethyl-propyleneamine oxime (99mTc-HM-PAO) exhibits favorable properties for regional cerebral tomograms in man utilizing conventional instrumentation (SPECT). Planar and tomographic studies using a rotating gamma camera equipped with a high sensitivity, low energy, collimator were performed in 5 normal subjects and 20 patients suffering from different cerebral diseases. SPECT abnormalities observed in patients with CVD, brain tumors and hydrocephalus were compared with results from X-ray CT. Our preliminary study demonstrates the feasibility of assessing regional brain perfusion using SPECT and a 99mTc radiopharmaceutical which is lipid soluble and has a high extraction fraction in the brain.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Humans; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, X-Ray Computed

We have compared the regional distribution of 99Tcm-HMPAO with regional cerebral blood flow (rCBF). CBF was measured by single photon emission computerized tomography (SPECT) using a TOMOMATIC 64 after 133Xe inhalation in 41 patients. With the same SPECT device the distribution of 99Tcm-HMPAO was measured after i.v. injection. High resolution (HR) and low resolution (LR) studies were performed yielding a resolution of 6 to 10 mm (HR) and 15 to 20 (LR). 99Tcm-HMPAO images showed close resemblance to xenon-133 CBF tomograms. Only about 20% of the (decay corrected) brain counts were lost during the first 24 h post injection. A slight decrease in contrast was measured comparing side-to-side asymmetry ratios from the serial studies. This loss of contrast is mainly due to back-diffusion and clearance of a part of the 99Tcm-HMPAO complex from the brain. It could be corrected for by a linearization algorithm. The slight loss of contrast will not be of any importance for the clinical use of this tracer complex.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Cerebrovascular Disorders; Humans; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Xenon Radioisotopes

Topics: Adult; Brain; Brain Diseases; Cerebrovascular Disorders; Epilepsy; Female; Headache; Humans; Middle Aged; Organometallic Compounds; Oximes; Reference Values; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

Topics: Amphetamines; Brain; Brain Diseases; Cerebrovascular Circulation; Humans; Iofetamine; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

Pure sensory stroke (PSS) is typically caused by a lacunar infarct located in the ventral-posterior (VP) thalamic nucleus contralateral to the paresthetic symptoms. The lesion is usually so small that it cannot be seen on computerized tomography (CT), as illustrated by our case. In our moderately hypertensive, 72-year-old patient with PSS, CT scanning and conventional nuclear magnetic resonance imaging (NMRI) scanning using a 7-mm-thick slice on a 1.5 Tesla instrument all failed to visualize the thalamic infarct. Using the high-resolution mode with 2-mm slice thickness it was, however, clearly seen. In addition, NMRI unexpectedly showed diffuse periventricular demyelinization as well as three other lacunar infarcts, i.e., findings characteristic of subcortical arteriosclerotic encephalopathy (SAE). This prompted psychometric testing, which revealed signs of mild (subclinical) dementia, in particular involving visiospatial apraxia; this pointed to decreased function of the right parietal cortex, which was structurally intact on CT and NMRI. Single photon emission computerized tomography by Xenon-133 injection and by hexamethyl-propyleneamine-oxim labeled with Technetium-99m showed asymmetric distribution of cerebral blood flow (CBF), with an 18% lower value in the right parietal cortex compared to the left side; this indicated asymmetric disconnection of the cortex by the SAE. Thus, the tomograms of the functional parameter, CBF, correlated better with the deficits revealed by neuropsychological testing than by CT or NMRI.

Topics: Aged; Brain; Brain Diseases; Cerebrovascular Circulation; Cerebrovascular Disorders; Dementia; Humans; Intracranial Arteriosclerosis; Magnetic Resonance Imaging; Male; Organometallic Compounds; Oximes; Syndrome; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Xenon Radioisotopes

D,L HM-PAO-99Tcm (PAO) is a lipophilic tracer complex which is avidly taken up by the brain. We have compared the regional distribution of PAO with regional cerebral blood flow (CBF). CBF was measured by single photon emission computed tomography (SPECT) by Tomomatic 64 after 133Xe inhalation in 41 patients. With the same SPECT the distribution of PAO was measured after intravenous injection. High resolution (HR) and low resolution (LR) studies were performed yielding a resolution of 6-10 mm (HR) and 15-20 mm (LR). PAO images showed close resemblance to 133Xe CBF tomograms. Only 20 per cent of the (decay corrected) brain counts were lost during 24 hours.

Topics: Brain; Brain Diseases; Cerebrovascular Circulation; Evaluation Studies as Topic; Female; Humans; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

After having outlined the importance of evaluating, in cerebral diseases, the regional cerebral blood flow by means of a non invasive method, the advantages of SPECT with Tc99m HM-PAO compared to the SPECT with radioxenon and iodoamphetamine are point out. The results obtained with this method on 28 different patients, six of with were normal subjects, while the remaining 22 were suffering: six from cerebro vascular disease, four from epilepsy, three from TIA, six from dementia, two from depressive syndrome and one from hemicrania are reported. The comparison of the results with literature references, proves that the tracer employed is definitely superior to TCT, while there is a coincidence with SPECT data obtained with radioxenon and iodoamphetamine. The radiotracer employed can be successfully used, due to its convenient physical-chemical features, in a daily routine, for the evaluation of regional cerebral blood flow in encephalic diagnostics.

Topics: Adult; Aged; Brain Diseases; Cerebrovascular Disorders; Dementia; Depressive Disorder; Diagnosis, Differential; Epilepsy; Evaluation Studies as Topic; Humans; Middle Aged; Oximes; Reference Values; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed