technetium-tc-99m-exametazime and Huntington-Disease

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

Functional neuroimaging with positron emission tomography previously demonstrated reduced caudate glucose metabolism in virtually all symptomatic patients with Huntington's disease (HD). Single-photon emission computed tomography studies of brain blood flow also have shown caudate abnormalities in patients with HD. The present study compared these two functional imaging modalities in 6 patients with HD who had been symptomatic for fewer than 5 years. All patients had significantly impaired caudate-thalamus and caudate-whole-slice glucose metabolism ratios as measured by positron emission tomography. However, only 3 had clearly abnormal caudate-thalamus activity ratios and 2 had clearly abnormal caudate-whole-slice ratios on single-photon emission computed tomography. These findings indicate that single-photon emission computed tomography imaging of caudate blood flow is a less sensitive indicator of caudate dysfunction in early HD than is positron emission tomography imaging of caudate glucose metabolism.

Topics: Anticonvulsants; Case-Control Studies; Caudate Nucleus; Deoxyglucose; Double-Blind Method; Female; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Humans; Huntington Disease; Lamotrigine; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Thalamus; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Triazines

The aim of this SPECT study was to determine whether there is a correlation between rCBF (99mTc-HMPAO) and D2 receptor binding (123I-IBZM) in disorders of the extrapyramidal system and in which situation the 99mTc-HMPAO scan could predict the outcome of the 123I-IBZM study. 13 patients with Parkinson's syndrome and 13 patients with hyperkinetic extrapyramidal disorders were studied. In all patients the two SPECT studies were performed within 2-7 days. ROIs were placed over the basal ganglia (BG), the frontal cortex (FC) and the cerebellum (CE). The ratios BG/FC and BG/CE were calculated. In both groups the scatter was lower when the frontal cortex was used as reference region. Among the patients with hyperkinetic extrapyramidal disorders the two patients with Huntington's chorea had lower rCBF and D2 receptor binding compared to other hyperkinetic extrapyramidal disorders. There was no correlation between D2 receptor binding and rCBF in the basal ganglia. The 99mTc-HMPAO studies did not provide clinically useful information, except in Huntington's chorea.

Topics: Adult; Aged; Basal Ganglia; Basal Ganglia Diseases; Benzamides; Brain; Cerebellum; Cerebrovascular Circulation; Dopamine Antagonists; Frontal Lobe; Humans; Huntington Disease; Iodine Radioisotopes; Middle Aged; Organotechnetium Compounds; Oximes; Parkinson Disease; Parkinson Disease, Secondary; Pyrrolidines; Receptors, Dopamine D2; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Previous research using functional transcranial Doppler sonography showed that blood flow velocity in the anterior cerebral artery is significantly less in patients with Huntington's disease (HD) than in healthy volunteers while they are completing mazes. The current research used SPECT to study regional cerebral blood flow (rCBF) in patients with HD during rest and maze testing.. Seven patients with HD and 9 healthy volunteers were injected twice with 0.96-1.15 GBq 99mTc-labeled hexamethylpropylene amine oxime. During the 10 min after injection, subjects either solved mazes or rested with their eyes open while looking at a modified maze. After SPECT, count density was obtained from 11 brain regions and corrected for decay and injected dose. Two types of data generated from this experiment, including absolute regional counts per pixel in the regions of interest and count density computed as a percentage of activity in the lateral cerebellum, were compared between groups.. During rest, the absolute regional count density was greater in the HD brains than in the healthy brains (P < 0.001). Count density was typically between 8% and 13% higher in the HD group than in the healthy group. The single exception was the caudate density, for which the 2 groups had similar values. No significant differences in absolute regional count density were observed between groups during maze testing. When rCBF was calculated as a percentage of cerebellar rCBF, analysis of covariance found decreases in HD caudate density (P < 0.001) and orbital frontal cortex density (P < 0.005) during maze testing. Changes in rCBF in the caudate nucleus predicted gene status (P = 0.0007) and correlated with time to complete the mazes (P < 0.05).. Patients with HD showed an increase in resting rCBF for all brain regions measured except the caudate nucleus. When rCBF was calculated as a percentage of cerebellar blood flow, rCBF in the striatum and orbital cortex in patients with HD was less during maze testing than during rest. Although the cause of these rCBF changes in HD patients is unclear, nitric oxide synthase, a regulator of vasomotor activity, may be involved.

Topics: Caudate Nucleus; Cerebellum; Cerebrovascular Circulation; Cognition; Female; Humans; Huntington Disease; Male; Middle Aged; Problem Solving; Psychological Tests; Radiopharmaceuticals; Rest; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Olanzapine, an atypical antipsychotic drug, was administered to a patient with Huntington's disease (HD) with marked choreiform movements. Brain SPECT with 99mTc-HMPAO was performed before and after treatment. Brain SPECT imaging has been performed in patients with HD in order to determine the status of basal ganglia perfusion. The use of brain SPECT with 99mTc-HMPAO before and after treatment in patients with HD has not been yet reported. The marked hypoperfusion of the basal ganglia on brain SPECT performed before therapy with olanzapine improved significantly after treatment.

Topics: Adult; Antipsychotic Agents; Benzodiazepines; Brain; Female; Humans; Huntington Disease; Olanzapine; Pirenzepine; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Huntington's disease (HD) is pathologically characterized by neuronal loss and neuroreceptor alterations in the striatum, including a reduction in dopamine receptor density. We evaluated the clinical usefulness of 123I-iodobenzamide (IBZM) D2 receptor SPECT imaging and 99mTc-hexamethylpropyleneamineoxime (HMPAO) brain perfusion SPECT imaging by studying four early symptomatic HD patients, 20 asymptomatic subjects at risk for HD and 22 controls. Striatal D2 receptor binding and perfusion were measured semiquantitatively by calculating striatum-to-frontal cortex IBZM and HMPAO uptake ratios, respectively. The control IBZM ratio (1.58 +/- 0.06) declined with age at 1.5% per decade (r = -0.58, p < 0.005), whereas the HMPAO ratio (1.15 +/- 0.05) did not. All four symptomatic patients had decreased IBZM ratios and three patients also had decreased HMPAO ratios. Five of 20 at-risk subjects had decreased IBZM ratios and two subjects also had decreased HMPAO ratios. Three of the five at-risk subjects showed subtle nonchoreic neurological abnormalities. Decreased striatal D2 receptor binding thus may be detected by IBZM-SPECT in the asymptomatic as well as symptomatic groups, and these changes were more marked than perfusion deficits detected by HMPAO-SPECT. IBZM-SPECT thus appears to be a promising method for early diagnosis and preclinical detection of HD.

Topics: Adolescent; Adult; Aged; Benzamides; Brain; Cerebrovascular Circulation; Female; Humans; Huntington Disease; Male; Middle Aged; Organotechnetium Compounds; Oximes; Pyrrolidines; Receptors, Dopamine D2; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

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

Topics: Alzheimer Disease; Cerebral Cortex; Cerebrovascular Circulation; Dementia; Dementia, Multi-Infarct; Humans; Huntington Disease; Organotechnetium Compounds; Oximes; Parkinson Disease; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Technetium 99m hexamethylpropylene-amine oxime (HMPAO) is trapped by cerebral grey matter and the basal ganglia on its first pass through the brain. To assess its potential for studying patients with diseases of the basal ganglia, a study of 15 normal volunteers and 32 patients with known or suspected basal ganglia disease have been investigated. Sixteen patients with idiopathic Parkinson's disease showed no abnormality of the basal ganglia and varying degrees of cerebral underperfusion consistent with their intellectual status. Eight patients with Huntington's chorea showed a characteristic pattern of reduced or absent caudate nucleus uptake. Patients with diseases affecting the basal ganglia, such as Fahr's disease, Wilson's disease and hemibalismus had varying degrees of basal ganglia underperfusion as demonstrated by an HMPAO scan. We believe that this new radiopharmaceutical for the demonstration of cerebral blood flow shows significant potential for the diagnosis and management of patients with basal ganglia disease.

Topics: Adult; Aged; Aged, 80 and over; Basal Ganglia Diseases; Cerebral Hemorrhage; Hepatolenticular Degeneration; Humans; Huntington Disease; Middle Aged; Organometallic Compounds; Oximes; Parkinson Disease; Technetium; Technetium Tc 99m Exametazime; Thalamic Diseases; Tomography, Emission-Computed; Tomography, X-Ray Computed

One hundred fourteen patients suffering from neuropsychiatric conditions have been studied using 99mTc-labeled hexamethylpropyleneamine oxime (HM-PAO) and single photon emission computed tomography (SPECT). Ninety-one patients had a firm clinical diagnosis while 23 were examined without knowledge of the clinical diagnosis. Of the 91 patients, 51 were suffering from dementia, 25 multi-infarct type and 26 Alzheimer's disease. In 19 of the Alzheimer's patients, a characteristic pattern of decreased perfusion in the parieto-occipital regions was demonstrated while those with multi-infarct type showed varying degrees of irregular uptake in the cerebral cortex. These appearances are similar to those shown with positron emission tomography (PET) and we believe that HM-PAO will provide a widely available method for identifying patients with Alzheimer's disease. Twenty-nine patients were suffering from diseases involving the basal ganglia. Fifteen patients with Parkinson's disease showed no significant abnormality in basal ganglia uptake, while 7 or 8 patients with Huntington's disease who had full examinations showed decreased uptake in the caudate nuclei. Similarly, four of six patients with other basal ganglia diseases showed impaired uptake by basal ganglia, and it is concluded that HM-PAO may be useful for the diagnosis and management of this type of patient. Twenty-three patients received HM-PAO imaging as part of their diagnostic work-up; in 19 of them, detailed follow-up was obtained, which indicated that in 7 cases the result of the HM-PAO scan altered the clinical diagnosis and in 9 cases resulted in a change in management. In the remaining 13 cases, the study was found to be helpful in confirming the diagnosis.

Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Basal Ganglia Diseases; Brain; Dementia; Female; Humans; Huntington Disease; Male; Middle Aged; Organometallic Compounds; Oximes; Parkinson Disease; Radionuclide Imaging; Technetium; Technetium Tc 99m Exametazime

Single photon emission computed tomography (SPECT) imaging of six Huntington's disease patients revealed a striking reduction in regional uptake of cerebral blood flow markers in vivo. Similar changes were found in one patient with "early stage" disease. The findings are compared with parallel magnetic resonance imaging (MRI) studies, and in one case, results of postmortem examination.

Topics: Adult; Aged; Aged, 80 and over; Brain; Caudate Nucleus; Cerebrovascular Circulation; Humans; Huntington Disease; Magnetic Resonance Imaging; Middle Aged; Organometallic Compounds; Oximes; Risk Factors; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

Huntington's chorea is an autosomal dominant inherited disease with a chronic course and atrophy of the corpus striatum. PET examination shows reduced glucose metabolism in the caudate nucleus. We examined seven patients with Huntington's chorea by SPECT, using 99mTc-HMPAO. All patients had cortical defects of varying severity. In addition, five patients showed increased uptake in the region of the caudate nucleus. The specific tracer uptake due to the metabolic processes in the region of the caudate nucleus in Huntington's chorea is discussed.

Topics: Caudate Nucleus; Humans; Huntington Disease; Organometallic Compounds; Oximes; Risk Factors; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

Topics: Alzheimer Disease; Brain; Dementia; Humans; Huntington Disease; Ischemic Attack, Transient; Organometallic Compounds; Oximes; Radionuclide Imaging; Technetium Tc 99m Exametazime