NEUROLOGICAL SEQUELAE OF CYANIDE INTOXICATION - THE PATTERNS OF CLINICAL, MAGNETIC-RESONANCE-IMAGING, AND POSITRON EMISSION TOMOGRAPHY FINDINGS

We report 2 patients with neurological sequelae of oral cyanide intoxi cation who were evaluated clinically and neuropsychologically, with hi gh-resolution magnetic resonance imaging and one of them with positron emission tomography. The clinical syndrome was characterized by extra pyramidal. motor and cerebellar symptoms such as bradykinesia, hypomim ia, slowed speech, antero-pulsion, and marked retropulsion, but little tremor. The sensory and pyramidal motor systems were normal or relati vely spared. On neuropsychological testing the intellectual capacity a nd memory functions were normal, whereas the speed of motor reaction a nd verbal fluency were reduced. Magnetic resonance imaging showed dama ge of the globus pallidus, putamen, substantia nigra, subthalamic nucl eus, and cerebellum in both patients, whereas the sensory-motor cortex and hippocampus were relatively spared. F-18-6-Eluoro-dopa positron e mission tomography revealed a symmetrical reduction of striatal dopa u ptake by 42% on average that was similar in the putamen and caudate. F -18-2-Fluoro-2-deoxyglucose positron emission tomography showed a regi onal reduction of the glucose metabolism in the posterior putamen and temporo-parieto-occipital and cerebellar cortex.