Quantification of the severity and distribution of cerebral atrophy provides diagnostic information in dementing

Purpose: The currently accepted view on the use of MRI in dementing disease is that it has little role to play in the diagnostic process. The hypothesis here is that this assertion is wrong. Materials and Methods: We show here how a reliable and fully automatic image analysis system is feasible which can provide a simple yet powerful analysis of the distribution of cerebrospinal fluid. The technique has been tested on a mixed group of 57 subjects. Analysis was performed using a combination of image processing segmentation and statistical classification techniques. All manual stages were performed by two independent operators in order to eliminate user error and to evaluate reproducibility. Results: The results indicate that this distribution, once corrected for normal ageing and head size, is highly characteristic of Fronto-temporal (FTD), Alzheimers (AD) and Vascular dementias (VD). The technique described here identified FTD patients from a population of AD and FTD with a sensitivity of 79 % and specificity of 72 % rising to 82 % and 92 % respectively after application of an 80 % probability threshold. These performance figures support the use of this approach as a diagnostic tool to help identify demented patients in whom a diagnosis of AD should be reviewed. Conclusions: Volumetric analysis of the distribution of cerebrospinal fluid provides a source of valuable information for diagnosis of dementing disease which is complementary to standard diagnostic practices.