Bilateral congenital macular coloboma: a case report

Bilateral congenital macular coloboma is a rare condition, with only a few cases documented in the literature. We report a case of a 62-year-old woman who presented to Quzhou People's Hospital in January 2022 with complaints of dryness and foreign body sensation in both eyes, along with a history of lifelong poor vision. Her best-corrected visual acuity was 20/500 in the right eye and 20/400 in the left eye, with a spherical equivalent refractive error of -9.0 diopters bilaterally. Anterior segment examination was unremarkable; however, fundus examination revealed well-demarcated chorioretinal atrophic lesions approximately four disc diameters in size at the macula of both eyes. Optical coherence tomography (OCT) demonstrated a large excavation involving the retinal and choroidal layers beneath the fovea, consistent with a diagnosis of bilateral congenital macular coloboma. The patient was treated with sodium hyaluronate eye drops for dry eye symptoms, while the coloboma itself required no intervention. In patients with unexplained visual impairment, thorough fundus examination and high-resolution OCT imaging are essential for accurate diagnosis.