[Visuo-constructional disorders and alexia-agraphia associated with posterior cortical atrophy]

A 57 year-old woman developed a slowly progressive environmental agnosia and dressing apraxia without disturbances of language, memory, orientation and social activities. Two years later, alexia, agraphia, visual agnosia, constructional apraxia, simultagnosia and imitation apraxia of nonsymbolic gestures were also noted. Ophthalmic examination demonstrated a left inferior quadranopsia. Oral comprehension was normal. There was no loss of insight, and behavioral response was appropriately concerned. Computed tomography and magnetic resonance imaging revealed bilateral cortical atrophy in parieto-occipital areas, most pronounced on the right side, with enlargement of the ventricles. Positron emission tomography demonstrated low flow and metabolism values in the right parietal, temporal and occipital regions. This case is very similar to those of posterior cortical atrophy recently reported by Benson et al. (1988). It suggests a selectively degenerative dysfunction of posterior association cortex, sparing oral language and verbal memory.