Background and purpose: The diagnosis of preclinical Alzheimer's disease (AD) (or mild cognitive impairment [MCI]) is loaded with a high degree of uncertainty. The aim was to test the accuracy of a computed tomography-based (CT-based) marker of medial temporal lobe atrophy, the radial width of the temporal horn (rWTH), in MCI.
Methods: Ten MCI and 42 AD patients and 29 nondemented controls underwent brain CT on the temporal lobe plane (slice thickness = 2 mm). The rWTH was taken on CT films with a precision caliper placed at the tip of the temporal horn radial to the curvature of the hippocampal head region.
Results: When specificity was fixed at 95%, the sensitivity for the detection of AD was 39/42 (93%) and that for the detection of MCI was 8/10 (80%).
Conclusion: The rWTH is a measure sensitive to the regional brain atrophy common in early AD.