Volume loss of the hippocampus and temporal lobe in healthy elderly persons destined to develop dementia

摘要: Objective To determine initial locus and rate of degeneration temporal lobe structures (total lobe, hippocampus parahippocampus) in preclinical dementia. Background Postmortem studies suggest that the earliest changes Alzheimer9s disease are neurofibrillary tangle formation adjacent cortex. MRI volume analysis over time subjects prior to developing dementia may allow identification when these processes begin, they develop, which areas key symptom development. Methods 30 nondemented (NOD), healthy, elderly individuals enrolled a prospective study healthy aging evaluated annually mean 42 months. Twelve with subsequent cognitive decline were assigned group (PreD). All 120 annual analyzed by volumetric techniques assessed differences volumes rates brain loss. Results NOD as well PreD had significant, time-dependent decreases hippocampal parahippocampal volume. Rates loss between groups did not significantly differ. cases smaller hippocampi asymptomatic. Parahippocampal differ cases. Significant atrophy was present only PreD. Conclusions Hippocampal occurs at similar regardless diagnostic group. Those who develop have begin with, but become symptomatic because accelerated Temporal mark beginning process within six years onset.