We read the recent article of Cappa et al with great interest.¹ Using HMPAO SPECT, the authors studied 24 patients diagnosed as having (probable) Alzheimer's disease (AD) on the basis of DSM-III-R and the NINCDS-ADRDA criteria. According to Butters et al, they distinguished, on the basis of neuropsychological tests, patients with a diffuse pattern of cognitive deficits (dAD) from those with focal temporal lobe dysfunction (FTLD).² Patients with FTLD are reported by both studies as having a better cognitive prognosis. Whereas the dAD group had diffuse perfusion deficits, the patients with FTLD showed a circumscribed reduction of tracer uptake in the left or right, or both temporal lobes.

We comment on the problem of suggesting AD in these patients with dementia. In the study of Butters et al, seven of the patients of the FTLD group underwent necropsy. Six had the typical histopathological signs of AD. One patient, however, . . . [Full text of this article]