Figure 1. Color anterior segment photographs showing grade 0 to grade 4 ARK, based on the 5-point scale. A: Grade 0 aniridia-related keratopathy (ARK): The limbal border is intact (4-year-old boy carrying gross deletion in PAX6, ELP4, and DKFZp686K1684). B: Grade 1 ARK: The limbal border is compromised, with vessels and conjunctival tissue invading into no more than 1 mm of the
limbus (3-year-old girl carrying mutation p.N9Sfs*17). C: Grade 2 ARK: The vessels and conjunctival tissue invade into the mid-peripheral cornea, but at least 2–3 mm of the central
cornea is spared (42-year-old woman carrying mutation p.Y90Lfs*2). D: Grade 3 ARK: The entire cornea surface is covered by the pannus, but the cornea remains translucent (46-year-old woman carrying
mutation p.D23Afs*29). E: Grade 4 ARK: The cornea is opaque and vascularized with a thick, irregular pannus (31-year-old man carrying mutation c.141+1G>T).