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

Psychotic symptoms are produced by distributed neuronal dysfunction. Abnormalities of reality testing and false inference implicate frontal lobe abnormalities.. To identify the functional imaging profile of patients with Alzheimer's disease manifesting psychotic symptoms as measured by single photon emission computed tomography (SPECT).. Twenty patients with Alzheimer's disease who had SPECT and clinical evaluations were divided into two equal groups with similar mini mental status examination (MMSE), age, sex, and the range of behaviours documented by the neuropsychiatric inventory (NPI), except delusions and hallucinations. SPECT studies, registered to a probabilistic anatomical atlas, were normalised across the combined group mean intensity level, and subjected to a voxel by voxel subtraction of the non-psychotic minus psychotic groups. Subvolume thresholding (SVT) corrected random lobar noise to produce a three dimensional functional significance map.. The significance map showed lower regional perfusion in the right and left dorsolateral frontal, left anterior cingulate, and left ventral striatal regions along with the left pulvinar and dorsolateral parietal cortex, in the psychotic versus non-psychotic group.. Patients with Alzheimer's disease who manifest psychosis may have disproportionate dysfunction of frontal lobes and related subcortical and parietal structures.

Topics: Alzheimer Disease; Brain Mapping; Cerebrovascular Circulation; Corpus Striatum; Delusions; Female; Frontal Lobe; Gyrus Cinguli; Hallucinations; Humans; Male; Parietal Lobe; Psychotic Disorders; Sex Factors; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

This study examined whether psychosis in Alzheimer's disease is associated with cerebral perfusion patterns appreciable by single photon emission computed tomography (SPECT) scans.. All cooperative outpatients enrolled in an Alzheimer's disease research center with the diagnosis of probable Alzheimer's disease and a Clinical Dementia Rating of mild or moderate were interviewed with their primary caregivers. Current and past psychiatric functioning was assessed by using the Hamilton Depression Rating Scale, the Structured Clinical Interview for DSM-III-R, and the Behavioral Pathology in Alzheimer's Disease Rating Scale. Patients without premorbid psychosis received SPECT scans, and the scans of the patients with delusions or hallucinations (N = 30) were compared to the scans of patients without these symptoms (N = 16).. The patients with delusions (N = 29) had hypoperfusion of the left frontal lobe in relation to the right frontal lobe. The patients with hallucinations (N = 10) had hypoperfusion in the parietal lobe.. Psychotic patients with Alzheimer's disease had a pattern of cerebral blood flow deficits significantly different from that of nonpsychotic patients. This suggests that patterns of cerebral dysfunction may be expressed symptomatically as psychosis.

Topics: Alzheimer Disease; Ambulatory Care; Brain; Cerebrovascular Circulation; Comorbidity; Delusions; Frontal Lobe; Hallucinations; Humans; Organotechnetium Compounds; Oximes; Parietal Lobe; Psychiatric Status Rating Scales; Psychotic Disorders; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Proceeding from the hypothesis that auditory hallucinations in psychotic patients have another biological basis than hallucinations provoked by hypnotic suggestion in healthy persons, we performed a symptom-comparative study by means of 99mTc-HMPAO single photon emission computed tomography. The results confirm the importance of pathogenesis in symptom-oriented psychiatric research.

Topics: Adult; Auditory Perception; Brain; Dominance, Cerebral; Female; Frontal Lobe; Hallucinations; Humans; Hypnosis; Male; Middle Aged; Organotechnetium Compounds; Oximes; Psychotic Disorders; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Topics: Cerebral Cortex; Depressive Disorder; Dominance, Cerebral; Humans; Neurocognitive Disorders; Organotechnetium Compounds; Oximes; Pilot Projects; Psychotic Disorders; Regional Blood Flow; Schizophrenia; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Regional cerebral blood flow (rCBF) was measured in relative terms with Tc99m-hexamethylpropyleneamineoxim and single photon emission computed tomography in 11 patients undergoing electroconvulsive therapy (ECT). The patients suffered from major depressive disorder (n = 8) or schizoaffective disorders (n = 3). rCBF was measured under general anesthesia 3 days prior to the ECT treatment and coinciding with the ECT stimulation. ECT caused a redistribution of the tracers uptake. The uptake became more pronounced in frontal parts of the brain and in the basal ganglia than in posterior parts of the cortex, and the thalamus. This selective effect of ECT on rCBF may be related to catecholaminergic projections to anterior parts of the brain.

Topics: Brain; Depressive Disorder; Electroconvulsive Therapy; Humans; Organotechnetium Compounds; Oximes; Psychotic Disorders; Radionuclide Imaging; Regional Blood Flow; Technetium Tc 99m Exametazime

In a symptom-oriented study 17 patients suffering from chronic auditory hallucinations were investigated by means of 99mTc-HMPAO-SPECT and compared with healthy controls. The results confirm the relative frontal hypoactivity in junction with a relative hyperactivity in the basal ganglia and mesial limbic structures in both hemispheres found in a previous pilot study in auditorily hallucinating patients. Our results should fortify the symptom-oriented approach in psychiatric research.

Topics: Adult; Auditory Perception; Basal Ganglia; Brain; Brain Mapping; Dominance, Cerebral; Female; Frontal Lobe; Hallucinations; Hippocampus; Humans; Male; Middle Aged; Organometallic Compounds; Oximes; Psychotic Disorders; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed