This document discusses an approach to early diagnosis of dementia based on comparing brain images. It involves calculating the distances between brain images rather than extracting predefined features. The distances represent how dissimilar the brain anatomies are. The approach was tested on brain MRI data from 490 subjects. Using only image information, it could correctly classify 80% of whether subjects who were healthy at baseline developed dementia 10 years later, outperforming classification based solely on age. This dissimilarity-based method shows promise as an approach for early dementia prediction based on brain image information.

1. Early diagnosis of dementia based on intersubject whole-brain dissimilarities Stefan Klein Biomedical Imaging Group Rotterdam (BIGR)

2. Research question: 1 Will the owner of this brain become demented?

14. Distance between images How ? 6

15. Nonrigid image registration fixed image moving image 7

16. Nonrigid image registration fixed image moving image 7

17. Nonrigid image registration fixed image moving image use “complexity of deformation field” as distance measure! 7

18. Nonrigid image registration fixed image moving image use “complexity of deformation field” as distance measure! Distance = std.dev. ( det ( jacobian ( deformation field ) ) ) 7

21. 9

22. 80% correctly classified 9

23. However:

24. However: Based on age alone: 69% correctly classified 10

25. However: Based on age alone: 69% correctly classified USE AGE-MATCHED CONTROLS!!! 10

27. Research question: 11 Will the owner of this brain become demented?

28. Research question: Will the owner of this brain become demented? Answer: YES! 11

31. Application: brain segmentation Atlas matching (Atlas = MR T1, multimodal registration required)