Diagnosis of Alzheimer's disease: MRI of the hippocampus vs delayed recall

Hippocampal volume measurements using magnetic resonance imaging (MRI) and assessment of performance in tests of delayed recall are among the most use ful aids for diagnosing early Alzheimer's disease (AD) on an individual lev el. However, their comparative diagnostic accuracy has not been previously addressed. In this study we compared the diagnostic accuracy of these two m ethods in 57 patients with probable AD according to the NINCDS-ADRDA criter ia, and 34 age- and gender-matched control subjects. The discriminatory pow er of the hippocampal volumes and delayed recall performance, Russel's Adap tation of the Visual Reproduction Test (VRT), were compared in discriminati on function and receiver operator characteristic analyses. Right and left h ippocampal volumes resulted in correct classification of 85.7-86.8% of the study subjects, respectively, while performance in the VRT resulted in corr ect classification of 93.4% of subjects. The area under curve value was 0.9 3 for the left hippocampus and 0.96 for the VRT. These data suggest that as sessment of delayed recall with the VRT is of high diagnostic accuracy, and may surpass the diagnostic accuracy of hippocampal volumetry. (C) 2000 Pub lished by Elsevier Science Ltd. All rights reserved.