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

Depression is a recognized feature of epilepsy. This study tested the hypothesis that depression arising in patients with epilepsy would be associated with decreased activity in brain regions previously demonstrated to be hypoperfused both in primary depression and in depression secondary to movement disorders. Two groups of patients with temporal lobe epilepsy were studied, one of which also met DSM IV criteria for a major depressive episode. All underwent a SPECT scan using the blood flow marker,(99m)Tc-HMPAO. An automated voxel-based analysis demonstrated no regions of relatively decreased activity in the depressed compared with the non-depressed patients. Sites of relative hyperactivity in the depressed group were concentrated in the left hemisphere, particularly in dorsolateral prefrontal cortex, striatum, thalamus and temporo-parietal regions. Comparison of these data with normal population data revealed that in the depressed epilepsy group regional activities were within the normal range whilst corresponding results from the non-depressed group were below it. Depressed patients with epilepsy have cerebral regions with greater perfusion than non-depressed people with epilepsy, although they are not hyperperfused compared with normals. Our results suggest that depression in people with epilepsy may arise from a mechanism which differs from that underlying the development of depression in patients with movement disorders.

Topics: Adult; Brain; Depressive Disorder, Major; Electroencephalography; Epilepsy; Female; Humans; Male; Movement Disorders; Psychiatric Status Rating Scales; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Despite the clinical and pathologic indicators implicating injury to the basal ganglia in children with hyperkinetic movement disorders, we were previously unable to identify lesions in these structures by means of cranial computed tomography or magnetic resonance imaging. We evaluated regional cerebral perfusion measured by single photon emission computed tomography (SPECT) with technetium 99m hexamethyl propylene amine oxime as a technique to localize functional cerebral abnormalities in eleven children who had a movement disorder after hypothermic cardiac surgery. Perfusion defects of the deep gray matter were noted in six of these eleven patients and cortical perfusion defects in nine. For both cortical and subcortical defects a strong right-sided predilection was present. Our findings suggest functional brain injury not detectable by conventional cranial computed tomography and magnetic resonance imaging in these patients. We speculate that these perfusion defects might relate to the behavioral and developmental sequelae in survivors of this syndrome. SPECT may identify subclinical injury in patients at risk for future neurodevelopmental problems and contribute to our understanding of the mechanisms of cerebral injury in the patient operated on for cardiac disease.

Topics: Brain; Cardiac Surgical Procedures; Cerebrovascular Disorders; Child; Child, Preschool; Female; Humans; Infant; Magnetic Resonance Imaging; Male; Movement Disorders; Organotechnetium Compounds; Oximes; Postoperative Complications; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Decompression sickness (DCS) is usually categorised as type I (mild; peripheral pain, non-neurological) or type II (serious; neurological). Type II is regarded as predominantly a spinal cord disease with infrequent cerebral involvement. Cerebral perfusion was studied by injection of 99Tcm-hexamethylpropyleneamine oxime and single photon emission tomography in 28 divers with confirmed incidents of DCS and cerebral arterial gas embolism (CAGE). Cerebral perfusion deficits were present in all 23 cases of type II DCS and in all 4 cases of CAGE. No deficits were present in the single case of type I DCS. Type II DCS should be recognised as a diffuse, multifocal, central nervous system disease.

Topics: Adolescent; Adult; Cerebrovascular Circulation; Decompression Sickness; Diving; Female; Functional Laterality; Humans; Intracranial Embolism and Thrombosis; Male; Middle Aged; Movement Disorders; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Time Factors; Tomography, Emission-Computed