technetium-tc-99m-exametazime and Mental-Disorders

Because of the treatment resistance and chronic affective lability of many post-traumatic stress disorder (PTSD) patients and the hypothesized association of these behaviors with temporal and limbic structures, a study was conducted to determine whether these patients would exhibit alterations in regional cerebral perfusion in the temporal and limbic regions compared with age-matched normal volunteers at rest.. We studied 17 patients using 99mTc hexamethyl propylene amine oxime single photon emission computed tomography. Seven of the patients were on a selective serotonin reuptake inhibitor, five were on a tricyclic antidepressant, and five were on no medication at the time of the study. Patients were compared with eight age-matched normal controls.. All PTSD patients showed a relative increase in regional cerebral perfusion in the anterior and posterior cingulate regions bilaterally, the right temporal and parietal regions, the right caudate/putamen region, and the left orbital and hippocampal regions compared with the control group. When the group of PTSD patients who were free of medication were compared with the control group, increased regional cerebral perfusion was found in the right and left caudate/putamen regions and the right orbital and anterior cingulate cortex bilaterally.. PTSD is associated with increased regional blood flow in limbic areas and the right temporal and parietal cortex compared with age-matched normal volunteers.

Topics: Adult; Analysis of Variance; Brain; Case-Control Studies; Humans; Limbic System; Male; Mental Disorders; Middle Aged; Statistics, Nonparametric; Stress Disorders, Post-Traumatic; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, Emission-Computed, Single-Photon

Brain SPECT studies are used to evaluate the cerebral hemodynamic changes in cerebrovascular diseases and other neuro-psychiatric disorders. I-123 and Tc-99m labeled radiopharmaceuticals widely used for brain perfusion SPECT studies include I-123 IMP, Tc-99m HMPAO, and Tc-99m ECD. I-123 IMP is suitable for the quantitative evaluation of cerebral blood flow, while Tc-99m HMPAO and Tc-99m ECD have problems owing to the non-linearity between cerebral radioactivity and cerebral blood flow. In addition, Tc-99m ECD does not show cerebral blood flow in the subacute phase of cerebral infarct or other conditions. Thus, it is important to consider the characteristics of radiopharmaceuticals and the clinical aspect of brain lesions in the interpretation of brain perfusion SPECT images. In this review, some useful information on brain perfusion SPECT is presented mainly as it relates to the cerebrovascular diseases.

Topics: Brain; Cerebrovascular Circulation; Cerebrovascular Disorders; Cysteine; Humans; Iofetamine; Mental Disorders; Organotechnetium Compounds; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Recent and future evolutions in neuroSPECT apply to radiopharmaceuticals techniques and the synergistic use of different imaging modalities in the work-up of neurological disorders. The introduction of Technetium labelled perfusion tracers, which could pass the intact blood-brain barrier, together with the implementation of the tomographic principle, by making the conventional gamma camera rotating, enabled estimation of regional cerebral blood flow and indirectly of local brain metabolism. In addition at present Thallium-201 and Tc-99m sestaMIBI allow functional detection of viable tumor tissue, without interference from previous surgery or radiotherapy as seen using CT-scan or MRI. In neurology this has led to the recognition of SPECT by the American Academy of Neurology (Therapeutics and technology subcommittee) as an established or promising tool in major neurological disorders such as dementia, stroke and epilepsy, while other domains such as brain oncology are considered investigational. With regard to radiopharmaceuticals, recent evolutions mainly include the development of mostly Iodine-123 labelled receptor ligands, some of which are already commercially available. For instrumentation advances consist e.g. of multidetector systems equipped with fanbeam collimators, attenuation and scatter correction or coincidence detection. Given the present role for nuclear neurology it may be expected that these additional radiopharmaceutical and technical innovations will continue to stimulate the development of SPECT of the brain. The synergistic use of several imaging techniques such as CT, (functional) MRI, source imaging, SPECT and PET represents a multimodal holistic approach to probe cerebral functions for research and clinical purposes. Clinical indications, in which this synergistic use is illustrated include e.g. support of the clinical diagnosis of dementia of the Alzheimer type, presurgical ictal detection of seizure focus, detection of acute ischemia and differential diagnosis between radiation necrosis and brain tumor recurrence. The synergistic use of imaging modalities, optimally applied using image fusion, allows to overcome the intrinsic limitations and to enhance the specific advantages of the different approaches as it leads to increased precision and accuracy, as well for spatial anatomofunctional correlation as for quantification.

Topics: Alzheimer Disease; Brain Ischemia; Brain Neoplasms; Epilepsy; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Mental Disorders; Nervous System Diseases; Neurology; Nitriles; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

To provide a basis for using neuroSPECT (single photon emission computerized tomography) in the evaluation of psychiatric disorders, this presentation will focus on recent developments in this field. Newer advances in cerebral SPECT instrumentation and radiopharmaceuticals and the potential impact on the evaluation of psychiatric patients will be discussed.

Topics: Amphetamines; Brain; Cerebrovascular Circulation; Cysteine; Humans; Iodine Radioisotopes; Mental Disorders; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Xenon Radioisotopes

The origin of altered (99m)Tc-HMPAO distribution at SPECT in psychiatric disorders is unknown. Correlations between brain (99m)Tc-HMPAO distribution and muscle succinate-cytochrome c reductase (SCR, complex II + III) were assessed in 20 unmedicated psychiatric patients. Significant negative correlations were found between (99m)Tc-HMPAO distribution in associative sensory regions and SCR activity. Sensory cortices are normally enriched in complex II activity. The production of electrons and reactive oxygen species affecting the redox state is considered to be highest from complex III, but complex II may also contribute. The negative relationship between (99m)Tc-HMPAO uptake and SCR activity may be due to redox state alterations influencing fixation of the radiopharmaceutical.

Topics: Adult; Brain; Female; Humans; Male; Mental Disorders; Mitochondria, Muscle; Muscle, Skeletal; Radiopharmaceuticals; Statistics as Topic; Succinate Cytochrome c Oxidoreductase; Technetium Tc 99m Exametazime; Tissue Distribution; Tomography, Emission-Computed, Single-Photon

A case of 49 years old woman with acute, severe suicidal carbofuran poisoning is described. The lowest activity of AChE was 0 IU/L. Because carbamates lead to multiorgan damages, especially affect central nervous system, computer tomography of the brain (CT) and examination of regional cerebral blood flow (99mTc-ECD SPECT) were done. No pathological changes were found in CT. 99mTc-ECD SPECT performed on 14th day of hospitalization, revealed disturbed regional cer- ' ebral flow generally in frontal and occipital lobes. Results of neuropsychological examination were pathological too.

Topics: Carbofuran; Cerebrovascular Disorders; Depression; Female; Humans; Insecticides; Mental Disorders; Middle Aged; Poisoning; Radiopharmaceuticals; Regional Blood Flow; Suicide, Attempted; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Treatment Outcome

The purpose of this retrospective study was to assess regional cerebral blood flow in patients after carbon monoxide intoxication by using brain single photon emission computed tomography and statistical parametric mapping. Eight patients with delayed neuropsychiatric sequelae and ten patients with no neuropsychiatric symptoms after carbon monoxide intoxication were studied with brain single photon emission tomography imaging with 99mTc-hexamethyl-propyleneamine oxime. Forty-four control subjects were also studied. We used the adjusted regional cerebral blood flow images in relative flow distribution (normalization of global cerebral blood flow for each subject to 50 ml x 100 g(-1) x min(-1) with proportional scaling) to compare these groups with statistical parametric mapping. Using this technique, significantly decreased regional cerebral blood flow was noted extensively in the bilateral frontal lobes as well as the bilateral insula and a part of the right temporal lobe in the patients with delayed neuropsychiatric sequelae as compared with normal volunteers (P< 0.005). In the patients with no neuropsychiatric symptoms, significantly decreased regional blood flow in the bilateral frontal lobes particularly on the left side was detected. There was a significantly decreased regional cerebral blood flow in the right frontal lobe and insula in the patients with delayed neuropsychiatric sequelae as compared to those with no neuropsychiatric sequelae. It is concluded that statistical parametric mapping is a useful technique for highlighting differences in regional cerebral blood flow in patients following carbon monoxide intoxication as compared with normal volunteers. The selectively reduced blood flow noted in this investigation supports the contention that the decrease following carbon monoxide intoxication may be prolonged and further worsen in the frontal lobe. In addition, the present study may help to clarify the characteristics of the pathophysiological alteration underlying delayed neuropsychiatric sequelae.

Topics: Adult; Aged; Brain; Carbon Monoxide Poisoning; Case-Control Studies; Cerebrovascular Circulation; Female; Humans; Image Processing, Computer-Assisted; Male; Mental Disorders; Middle Aged; Organotechnetium Compounds; Oximes; Radiopharmaceuticals; Retrospective Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Two-dimensional SPECT display and three methods for integrated visualization of SPECT and MRI patient data are evaluated in a multiobserver study to determine whether localization of functional data can be improved by adding anatomical information to the display.. SPECT and MRI data of 30 patients were gathered and presented using four types of display: one of SPECT in isolation, two integrated two-dimensional displays and one integrated three-dimensional display. Cold and hot spots in the peripheral cortex were preselected and indicated on black-and-white hard copies of the image data. Nuclear medicine physicians were asked to assign the corresponding spots in the image data on the computer screen to a lobe and a gyrus and give a confidence rating for both localizations. Interobserver agreement using kappa statistics and average confidence ratings were assessed to interpret the reported observations.. Both the interobserver agreement and the confidence of the observers were greater for the integrated two-dimensional displays than for the two-dimensional SPECT display. An additional increase in agreement and confidence was seen with the integrated three-dimensional display.. Integrated display of SPECT and MR brain images provides better localization of cerebral blood perfusion abnormalities in the peripheral cortex in relation to the anatomy of the brain than single-modality display and increases the confidence of the observer.

Topics: Cerebral Cortex; Child; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Mental Disorders; Observer Variation; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The diagnosis of central nervous system (CNS) involvement appears to be a major problem in systemic lupus erythematosus (SLE), especially when the clinical signs are non-specific or neuroimaging is unremarkable. Two SLE patients with mild neuropsychiatric manifestations were studied with magnetic resonance imaging (MRI), single photon emission tomography (SPET) and localized proton magnetic resonance spectroscopy (H-1 MRS). MRI was normal in both patients. SPET revealed areas of hypoperfusion in both patients. H-1 MRS demonstrated metabolic abnormalities in the regions corresponding to the hypoperfused areas. A correlation between H-1 MRS and SPET was noted: patients with mild neuropsychiatric SLE may have disturbances evident on SPET and H-1 MRS in the presence of normal anatomy on MRI, suggesting that CNS involvement in SLE has very strong physiological and neurometabolic components in individual patients.

Topics: Adult; Brain; Female; Humans; Lupus Erythematosus, Systemic; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Mental Disorders; Middle Aged; Nervous System Diseases; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Central nervous system (CNS) involvement in patients with systemic lupus erythematosus (SLE) is often difficult to evaluate because of protean neuropsychiatric (NP) manifestations and lack of reliable diagnostic markers. In the reported study the role of single-photon emission tomography (SPET) with technetium-99m hexamethylpropylene amine oxime (HMPAO) in the evaluation of CNS involvement in SLE was assessed and the relations between SPET perfusion defects, EEG examination, magnetic resonance imaging (MRI) findings and clinical presentation were examined. Twenty SLE patients with different NP manifestations were studied. Multiple areas of hypoperfusion, especially in the territory of the middle cerebral artery, were demonstrated by SPET analysis in all 20 patients. The number of hypoperfused areas and the degree of hypoperfusion, expressed by an asymmetry index (AI), were more marked in patients with multiple NP manifestations. MRI and EEG evaluations were positive for 14 of 18 and for 12 of 20 patients, respectively. In the patients with positive SPET and MRI, 87 MRI focal lesions and 63 hypoperfused areas were found, and for 51 of these 63 at least one MRI lesion was found in the same anatomical region. SPET examination of patients with a normal EEG showed fewer hypoperfused areas and a lower degree of asymmetry compared to patients with an abnormal EEG. SPET of patients with focal EEG abnormalities showed more hypoperfused areas (difference not statistically significant) and a higher AI than did SPET of the patients with diffuse EEG abnormalities. Seven of 11 anatomical regions with focal EEG abnormalities.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Brain; Central Nervous System Diseases; Cerebrovascular Circulation; Electroencephalography; Female; Humans; Lupus Erythematosus, Systemic; Magnetic Resonance Imaging; Mental Disorders; Organotechnetium Compounds; Oximes; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The authors present a case of basilar artery migraine in a 33-year-old woman who was initially misdiagnosed as having a cerebrovascular or mental disorder and subjected to MRI and cerebral angiography, which, however, did not show any pathologic findings. During admission to the university hospital, she lost consciousness. An emergency Tc-99m HMPAO brain SPECT showed a significant decrease of regional cerebral blood flow in the right temporal and occipital cortices, and right cerebellar hemisphere, where regional cerebral blood flow was decreased by 10-24% as compared to the left side. The second brain SPECT during a symptom-free phase showed the reversion of regional cerebral blood flow to normal in these areas. Basilar artery migraine was diagnosed by the finding of reversible ischemia in the territory of the right basilar artery on brain SPECT images and the clinical picture.

Topics: Adult; Brain; Cerebrovascular Circulation; Cerebrovascular Disorders; Diagnostic Errors; Female; Humans; Mental Disorders; Migraine Disorders; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Vertebrobasilar Insufficiency

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

To study cerebral abnormalities in myotonic dystrophy (MD) and determine the different patterns of cerebral function in patients with MD with maternal (mMD) vs paternal (pMD) inheritance.. Patients with MD and normal controls were studied with neuropsychological testing, magnetic resonance imaging, and single photon emission computed tomography.. Studies were done at Harbor-UCLA Medical Center, Torrance, Calif.. Twenty-two consecutive-patients with MD, 11 of whom had pMD and eight mMD, and 10 normal controls were studied. Diagnoses were made on the basis of family history, electromyography, and clinical examinations. Normal subjects in the same age distribution were studied for comparisons.. We found significantly lower neuropsychological performance and cerebral blood flow in the patients with MD compared with the controls. Patients with mMD had statistically lower scores on IQ tests and more extensive cerebral hypoperfusion when compared with those with pMD. Changes in cerebral blood flow were most severe in the frontal and temporoparietal association cortex. Cerebral blood blow measures strongly correlated with IQ.. Patients with mMD had earlier onset of disease and lower IQs than the pMD group. The pattern of cerebral perfusion in the mMD group was consistent with a diffuse brain injury, while cerebral perfusion in pMD showed more minor changes. These findings emphasize the cognitive differences between mMD and pMD.

Topics: Adolescent; Adult; Cerebrovascular Circulation; Child; Female; Humans; Intelligence; Magnetic Resonance Imaging; Male; Mental Disorders; Middle Aged; Myotonic Dystrophy; Neuropsychological Tests; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

This brief paper introduces the reader to the materials presented in other manuscripts of this issue of The Journal of Clinical Psychiatry. Single photon emission computed tomography (SPECT) is a dynamic brain imaging technique that grew out of the evolution of increasingly more sophisticated approaches to understanding the pathophysiology and biology of neurologic and psychiatric disorders over the past two decades. SPECT is a practical tool that is more available than positron emission tomography (PET), which is found primarily at academic centers. While SPECT has drawbacks that relate to levels of resolution and the possible impact of altered brain physiology on interpretation of results, it offers advantages of decreased cost, the need for less intensively trained technicians, and the ability to carry out clinical testing in facilities lacking a cyclotron. These factors raise the hope of more routine use of this imaging technique in clinical settings related to cognitive disorders, schizophrenia, affective disorders, and problems associated with substance use.

Topics: Amphetamines; Brain; Humans; Iodine Radioisotopes; Mental Disorders; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Xenon Radioisotopes

Technetium-99m hexamethylpropyleneamineoxime ([99mTc]HM-PAO) brain single photon emission computed tomography (SPECT) was performed with a dual head rotating scintillation camera. Normal tracer distribution and side/side differences of counting rates were obtained in 11 healthy volunteers. Almost stable gray/white matter ratios were found (1.97-2.1) in one normal subject during 2 hr after tracer administration. Eighty-three investigated patients had the following diagnoses (in parentheses is percent of positive findings in each group): cerebral vascular disease 18 (94.4%), epilepsy 23 (82.6%), extrapyramidal disorders 8 (100%), dementia 12 (100%), headache 11 (63.6%), psychiatric disorders 11 (27.3%). In addition, SPECT was performed in 28 male volunteers during motor or visual imagery tasks and a significant increase (p = 0.035) of relative tracer deposition was observed in the left inferior occipital region during visual imagery when compared with motor imagery. The results indicate that [99mTc]HM-PAO SPECT is valuable for demonstrating pathologic and physiologic changes of the brain.

Topics: Adult; Aged; Basal Ganglia Diseases; Brain; Cerebrovascular Circulation; Cerebrovascular Disorders; Dementia; Epilepsy; Female; Headache; Humans; Imagination; Male; Mental Disorders; Middle Aged; Organometallic Compounds; Oximes; Technetium; Technetium Tc 99m Exametazime; Tomography, Emission-Computed