technetium-tc-99m-bicisate and Amnesia

We report a 48-year-old patient with neuro-Behcet's disease who presented with the combination of severe memory impairment and frontal/executive dysfunction. The clinical feature mimicked that of diencephalic amnesic syndrome. The MRI and SPECT findings supported the notion that the thalamus and related subcortical-frontal connection was responsible for this patient's problem.

Topics: Amnesia; Attention; Behcet Syndrome; Brain; Cysteine; Executive Function; Frontal Lobe; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Trail Making Test

We report a right-handed 67-year-old woman with an infarction in the left posterior cerebral artery territory presenting amnesic syndrome, right homonymous hemianopsia, pure alexia, color anomia, and defective route finding. The patient often walked in wrong directions out of her hospital room as well as in her home. She was able to recognize her own house and nearby streets by looking at them. Prosopagnosia and constructional impairment was not observed. Wechsler memory scale revised (WMS-R) revealed that she had marked disturbance in both visual and verbal recent memory. Brain MRI revealed an infarction involving the left medial inferior temporal and left medial occipital lobe, the left splenium of corpus callosum, and the left retrosplenial region. SPECT indicated a defect in the left medial occipital lobe and hypoperfusion in the left medial temporal lobe. Cerebral angiography demonstrated stenosis of the left medial occipital artery and occlusion of the left dorsal corpus callosal branches and the left calcarine artery. We conclude that left hippocampus, left parahippocampal gyrus and the left retrosplenial region may cause memory disturbance in our case. The lesion in the left retrosplenial region may have contributed to the occurrence of defective route finding. The relation between defective route finding and the retrosplenial amnesia is discussed.

Topics: Aged; Amnesia; Brain; Cerebral Angiography; Cerebral Infarction; Cysteine; Female; Humans; Magnetic Resonance Imaging; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals

Regional resting cerebral blood flow and vascular reserve in a patient with transient global amnesia (TGA) were evaluated during and after a TGA episode using 99mTc-ethyl cysteinate dimer (ECD). The patient had consecutive SPECT studies before and after acetazolamide (ACZ) administration with adjunctive radionuclide angiography using equal-volume-split 99mTc-ECD. SPECT study during TGA episode showed poor vasodilatory reactivity to ACZ in the left medial temporal region involving the hippocampus and resting hypoperfusion in the regions bilaterally. The resting hypoperfusion with reserved vasodilatory reactivity to ACZ also was seen in the bilateral thalami. Abnormal findings in these regions disappeared on the follow-up SPECT study 15 days after the onset. No previous SPECT evaluation of regional abnormalities of both hemodynamic reserve and resting perfusion during and after an episode of TGA has been reported.

Topics: Acetazolamide; Amnesia; Brain; Cerebrovascular Circulation; Cysteine; Humans; Male; Middle Aged; Organotechnetium Compounds; Radionuclide Angiography; Radiopharmaceuticals; Time Factors; Tomography, Emission-Computed, Single-Photon