Transdifferentiation and Intrachoroidal Migration of Melanotic Retinal Pigment Epithelium in Punctate Inner Choroiditis.

ABSTRACT

PURPOSE: To report the multimodal imaging features of hyperpigmented chorioretinal lesions originating from the retinal pigment epithelium (RPE) within punched-out lesions of punctate inner choroidopathy (PIC). METHODS: Retrospective case report. Multimodal imaging findings including fundus photography, optical coherence tomography (OCT), and OCT-angiography (OCTA) were analyzed. RESULTS: A 49-year-old female with myopic degeneration developed progressive lesions of PIC requiring immunosuppressive therapy with adalimumab. Within areas of punched-out chorioretinal atrophic lesions, the occurrence of hyperpigmented lesions were observed which enlarged and extended into the choroid over a multiyear follow-up. CONCLUSION: This case illustrates the development of pigmented choroidal lesions appearing to originate from the RPE through transdifferentiation following previous chorioretinal inflammatory lesions. The introduction of adalimumab treatment may have activated the cellular migration of the RPE. To the best of our knowledge, this is the first report of intrachoroidal RPE migration in PIC.