Which iris nodules are located at the pupil margin?

Which iris nodules are located at the pupil margin?

• A. Koeppe Nodules
• B. Busacca Nodules
• C. Keratic Precipitates
• D. Lisch Nodules

Answer: (A)

Pupillary margin localization helps distinguish iris nodules seen with anterior uveitis. Koeppe nodules form exactly at the pupillary margin on the iris surface, making them the nodules you’d expect to see at the edge where the iris meets the pupil. In contrast, Busacca nodules sit on the iris surface away from the pupil, within the stroma. Keratic precipitates lie on the corneal endothelium, not the iris, and Lisch nodules are pigmented iris lesions seen in neurofibromatosis type 1, not specifically tied to the pupil margin. So, the nodules located at the pupil margin are Koeppe nodules.

Pupillary margin localization helps distinguish iris nodules seen with anterior uveitis. Koeppe nodules form exactly at the pupillary margin on the iris surface, making them the nodules you’d expect to see at the edge where the iris meets the pupil. In contrast, Busacca nodules sit on the iris surface away from the pupil, within the stroma. Keratic precipitates lie on the corneal endothelium, not the iris, and Lisch nodules are pigmented iris lesions seen in neurofibromatosis type 1, not specifically tied to the pupil margin. So, the nodules located at the pupil margin are Koeppe nodules.