The role of CT and MRI in the assessment of dementia of Alzheimer type

Purpose: To test the predictive value of atrophy of hippocampal formation (HF) in detecting dementia of Alzheimer type (DAT) patients with CT and MRI. Materials and methods: A total of 30 subjects (13 DAT patients and 17 normal volunteers) were studied with CT. The MR examinations were performed in 13 subjects (8 DAT and 5 normal). The width of choroidal fissure/hippocampal fissure on CT and MR imaging was measured to assess the HF volume. Results: MMSE sensitivity exceeded that of choroidal fissure/hippocampal fissure in DAT patients and the specificity of choroidal fissure/hippocampal fissure was superior to that of MMSE in normal volunteers. A significant correlation (P<0.05) between MMSE score and HF volume was observed in all DAT patients. Conclusion: Dilatation of choroidal fissure/hippocampal fissure and reduction of HF volume were a useful radiologic marker for the diagnosis of DAT