Figure 3.

Representative micro images showing different grades and some limitations of the alternative arteriolar hyalinosis scoring system. (a) Arteriole with nodular replacement of the smooth muscle by hyaline. This met criteria for aah1 or aah2 scoring depending on the number of involved arterioles. (b) Arteriole with circumferential replacement of muscularis by hyaline. These features directly meet criteria for an aah3 score regardless of the number of involved arterioles. (c) Arteriole with severe circumferential subendothelial hyalinosis not replacing the muscularis. Despite the extensive hyalinosis, this arteriole would not meet criteria for a significant aah score (aah0) (all images, periodic acid–Schiff, original magnification ×600).