[A case of idiopathic superficial siderosis of the central nervous system]

A 59-year-old man developed a staggering and wide based-gait in July 1990. Dysarthria, hearing loss, vexation and disturbance of memory appeared in January 1991. He consulted our clinic in May 1991, and cerebellar ataxia, neurogenic bladder, and cerebellar atrophy on brain CT were noted. Subsequently, he was followed as OPCA. Brain and spinal cord MRI (T2 and proton weighted images) revealed hypointensity on the surface of the Sylvian fissure, cerebellum, brainstem and spinal cord. We diagnosed this case as superficial siderosis because of the clinical course, i.e. cerebellar ataxia, dementia and sensorineural hearing impairment, and specific findings on MRI. We consider this case idiopathic superficial siderosis because the origin of the bleeding source was unknown. IMP-SPECT showed low perfusion in the cerebellum and frontal lobe where hemosiderin was heavily deposited. RI cisternography revealed a disturbance of CSF absorption even after 48 hours. The basic rhythm on EEG was slow alpha band with sporadic theta waves dominantly in the frontal lobe. His central conduction time on ABR and SEP was delayed, OKN was poorly elicited and ETT exhibited a staircase pattern. The physiological results as well as the clinical manifestations of the present case suggest that hemosiderin deposit on the surface of brain and spinal cord caused serious damage to the underlying structures.(ABSTRACT TRUNCATED AT 250 WORDS)