Interstitial Keratitis (Parenchymatous Keratitis) By Melvin I Roat, MD, FACS, Sidney Kimmel Medical College at Thomas Jefferson University Reviewed / Revised Aug 2022 | Modified Sep 2022 View Patient Education Symptoms and Signs Diagnosis Treatment Key Points Topic Resources Keratitis (Interstitial) Interstitial keratitis is chronic, nonulcerative inflammation of the mid-stroma (the middle layers of the cornea) that is sometimes associated with uveitis.