Peripheral pigmented placoid corneal endotheliopathy
C. Observation with close follow-up
We present a case of a 59-year-old man, with history of stage 3B melanoma of the trunk but no trauma, intraocular surgery, or intraocular inflammation, who had a flat, pigmented, well-demarcated corneal endothelial lesion with scalloped edges. On gonioscopy, the pigmented lesion was located in the cornea without extension past the Schwalbe line and did not involve other angle structures such as the trabecular meshwork or scleral spur (Figure, B).
The patient most likely has a benign condition called peripheral pigmented placoid corneal endotheliopathy (PPPCE) given its morphology and location in the cornea without involvement of other ocular structures, and the most appropriate next step would be observation with close follow-up (choice C). The differential diagnosis includes uveal melanoma, pigment dispersion syndrome, trauma, or inflammatory etiology. Given the medical history of metastatic melanoma, uveal melanoma should be considered. However, there was no extension of the lesion into the angle on gonioscopy and no masses were identified on UBM. There have been prior reports of corneal melanoma secondary to infiltration from the limbus or in the setting of prior ocular surgery or trauma.1- 3 Management of corneal melanoma consists of surgical resection, with or without cryotherapy, biopsy, and postoperative topical chemotherapy.3 The patient denied a history of surgery or trauma and there were no masses visualized on examination or imaging. Therefore, corneal biopsy (choice A) or surgical excision (choice B) was not recommended as the next step as these would be invasive and inappropriate at this stage. Corneal endothelial pigmentation could be due to trauma or inflammatory causes. However, the patient denied a history of trauma, he was asymptomatic, and there was no evidence of intraocular inflammation on examination. Given this history and examination findings, prednisolone drops (choice D) would not be indicated. Pigment dispersion syndrome is unlikely given the appearance of the trabecular meshwork, normal intraocular pressure, and lack of symptoms associated with this disease.