NEUROFIBRILLARY DEGENERATION AND CELL LOSS IN THE NUCLEUS BASALIS IN COMPARISON TO CORTICAL ALZHEIMER PATHOLOGY

Neurofibrillary tangle staging was compared in the nucleus basalis and cerebral cortex of Alzheimer's disease patients with and without Lewy body disease. In pure Alzheimer's disease, cholinergic nucleus basali s cell number, as determined from counts in serial forebrain sections, was 22-60% of control mean, with the majority of residual cells conta ining tangles. A comparison between control cell number and the combin ed number of tangles plus tangle-free neurons in pure Alzheimer's dise ase suggests that the majority of nucleus basalis neurons were lost th rough neurofibrillary degeneration. The staging of neurofibrillary deg eneration in the nucleus basalis was discordant with cortical changes as some controls had more extensive tangle formation in the nucleus ba salis than in the cerebral cortex. Patients having both Alzheimer's di sease and Lewy body pathology had few or no tangles in the nucleus bas alis despite greater loss of neurons than purely demented patients. Th e presence of concomitant pathology had a greater effect on nucleus ba salis tangle burden than did cortical disease stage, suggesting dichot omous disease processes in the cerebral cortex and forebrain. (C) 1998 Elsevier Science Inc.