[en] PET studies have demonstrated bilateral temporo-parietal hypoperfusion and hypometabolism in probable and definite Alzheimer's disease (AD), a pattern that may help differentiate AD from other dementias. METHODS: To evaluate the diagnostic power of cerebral metabolic distribution patterns for "cortical" degenerative dementias, PET scans obtained from 129 patients referred for differential diagnosis of dementia were analyzed visually. RESULTS: Sixty-five patients had a final clinical diagnosis of probable AD. Ninety-seven percent (97%) of those had abnormal metabolic scans and 94% showed a suggestive pattern of bilateral or unilateral temporo-parietal hypometabolism (with or without frontal involvement). Hypometabolism was unilateral in 23% of patients. Five subjects with a neuropathologically proven diagnosis of Alzheimer's disease had a suggestive metabolic pattern. One of those was an early case with frontal hypometabolism exceeding temporo-parietal involvement. Two patients with Alzheimer's-type dementia had isolated bilateral frontal hypometabolism. CONCLUSIONS: This alternative metabolic pattern may correspond to a non-Alzheimer pathology occurring in 10%-20% of patients suffering from clinically probable Alzheimer's disease. Most of the patients with possible but atypical Alzheimer's-type dementia showed isolated bilateral frontal involvement. This metabolic pattern probably corresponds to different diseases, such as Pick's disease, frontal lobe dementia or progressive subcortical gliosis.
Disciplines :
Neurology
Author, co-author :
Salmon, Eric ; Université de Liège - ULiège > Département des sciences cliniques > Neuroimagerie des troubles de la mémoire et révalid. cogn.
Sadzot, Bernard ; Université de Liège - ULiège > Département des sciences cliniques > Département des sciences cliniques
Maquet, Pierre ; Université de Liège - ULiège > Centre de recherches du cyclotron
Degueldre, Christian ; Université de Liège - ULiège > Centre de recherches du cyclotron
Lemaire, Christian ; Université de Liège - ULiège > Centre de recherches du cyclotron
Rigo, Pierre ; Université de Liège - ULiège > Département des sciences de la motricité > Département des sciences de la motricité
Comar, D.
Franck, Georges ; Université de Liège - ULiège > Relations académiques et scientifiques (Médecine)
Language :
English
Title :
Differential diagnosis of Alzheimer's disease with PET.