In this video, Dr. Perez discusses the clinical presentation and etiology of peripheral ulcerative keratitis (PUK). He likens ulcerative keratitis to the "tip of the iceberg" because it is often the presenting manifestation of potentially lethal autoimmune disorders, systemic disorders, and infections. Early diagnosis of systemic vascular disease and subsequent treatment with chemotherapy can prolong survival and improve the quality of life in these patients. Additionally, the geographical location of a practice can also change the differential diagnosis. Dr. Perez advises a step-ladder approach to the medical and surgical management of PUK.