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

Regional cerebral blood flow was studied using 99mTc-HM-PAO and single photon emission computed tomography (SPECT) in five healthy subjects and in eight patients with clinical and computed tomography (CT) features of subcortical arteriosclerotic encephalopathy. All the patients and controls underwent magnetic resonance imaging (MRI). Circumscribed cortical hypoperfusion was observed in three patients, and in one case there was no evidence of cortical or sulcal alterations on MRI. In all the patients, a reduction of the white matter perfusion was found in periventricular and/or supraventricular regions. This pattern was substantially correlated with the typical white matter hyperintensities shown by MRI scans. These findings support the hypothesis that white matter hypoperfusion is the most prominent functional abnormality in subcortical arteriosclerotic encephalopathy.

Topics: Aged; Brain; Cerebrovascular Circulation; Dementia; Demyelinating Diseases; Female; Humans; Intracranial Arteriosclerosis; Magnetic Resonance Imaging; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Topics: Adult; Brain Neoplasms; Cranial Irradiation; Demyelinating Diseases; Diagnosis, Differential; Humans; Magnetic Resonance Imaging; Male; Technetium Tc 99m Exametazime; Thalamus; 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