Objective: To describe the pathologic changes that caused a left homon
ymous hemianopsia in a patient with dementia with Lewy bodies. Design:
Report of a case and postmortem studies. Main Outcome and Results: A
66-year-old woman experienced parkinsonism and left homonymous hemiano
psia early in the course of a rapidly progressive dementia that culmin
ated in death only 21 months after the onset of her symptoms. Postmort
em examination revealed pathologic features consistent with the diagno
sis of dementia with Lewy bodies. The only apparent explanation for he
r visual field deficit was a disproportionately large number of neurof
ibrillary tangles in the right striate, peristriate, and inferotempora
l cortices. Conclusion: A clinically obvious homonymous hemianopsia ca
n result from the occipital and inferotemporal cortical degeneration i
n dementia with Lewy bodies.