Early and focal atrophy of medial temporal lobes on magnetic resonance imaging (MRI) in patients with Alzheimer disease (AD) can be measured in several ways.

In 20 patients with probable Alzheimer disease and 29 cognitively normal elderly medial temporal lobe atrophy (MTA) was measured by volumetry using manual tracing of the hippocampus. The volume of the hippocampus was also rated into five categories expressed as MTA scores ranging from 0 (no atrophy) to 4 (severe atrophy) using a simple and quick semiquantitative method according to the published combined widths or the height of selected three mediotemporal structures.

In comparison to controls, AD patients had significantly smaller volume of either hippocampus (median volume of the hippocampus Hipp dx: 1,81 vs 2,23 p=0,001; Hipp sin: 1,60 vs 2,14 p=0,003; Hipp bilat: 3,40 vs 4,31 p=0,0004). The total MTA score of both sides were significantly higher in AD patients (median 4) than that in controls (median 1) (p=0,0004). Nearly 60 % cognitively normal seniors had the MTA score ≤ 0,5. A similar proportion of patients with AD (65 %) had the MTA score ≥ 2.

Hippocampal loss of tissue can be detected by visual rating and volumetry on MRI in patients with AD. Visual MTA rating is the easier and quicker method than more accurate and time consuming volumetry to support the diagnosis of AD on the brain MR imaging.

The project was supported by CNS MSMT 1M0517 and VZ MZČR MZ0PCP2005.