Fig. 5

a is the same patient with Fig. 1. b is a 35-year-old patient who had DVA coexisting with CM. Both of them are enhanced T1 images. In b the wildest diameter of medullary veins is 1.77 mm, the wildest diameter of draining vein is 3.10 mm, the narrowest diameter of draining vein is 1.29 mm. So in b the stenosis rate of draining vein is (1-1.29/3.10) × 100 % = 58.39 %, the stenosis rate of medullary vein is (1-1.77/3.10) × 100 % = 42.90 %. In A, the same way was used