Choroidal Nevus with Choroidal Detachment Simulating Intraocular Melanoma - Image and Pathology Studies

Purpose: Malignant uveal melanoma is the most common primary intraocular malignant tumors in adults. Choroidal detachment and choroidal nevus may be confused with choroidal tumors. We report a case of choroidal nevus and rhegmatogenous retinal detachment (RD) complicated with macular pucker and choroidal detachment simulating intraocular melanoma.

Method: Interventional case report.

Results: A 59-year-old woman complained of visual disturbances and superior temporal visual defect for 1 month in the left eye. Funduscopy revealed macular pucker with lower RD and an elevated lesion with pigment mottling in the nasal-lower quadrant. The optical coherence tomography (OCT) scan showed macular pucker with subretinal fluid. B scan ultrasonography showed low to moderate internal reflectivity. Fluorescein angiography demonstrated irregular pattern of mixed hypo- and hyperfluorescence in the elevated lesion and dye pooling on the posterior pole. Computed tomography (CT) revealed an intraocular enhancing mass. Positron-emission tomography/computed tomography (PET/CT) showed no abnormal 18F-fluoro-2-deoxyglucose uptake. Because the evidence of malignancy was not solid and the patient also sought to improve her vision, the small gauge vitrectomy was performed. A retinal break was found on the slope of choroidal detachment intraoperatively. Specimens were taken through the retinal break. Internal limiting membrane peeling, air-fluid exchange, focal laser around the retinal break and C3F8 tamponade were done. The postoperative magnetic resonance imaging (MRI) showed no clue of enlargement. Due to mild hyperintensity on T1-weighted imaging, choroidal melanoma was suspected by the radiologist. However, pathology showed no malignancy. The retina was attached and the retinal break was sealed on the slope during 34-month follow up.

Conclusion: Choroidal nevus and choroidal hemorrhage with detachment should be carefully differentiated from choroidal melanoma. Apart from CT and MRI, PET/CT can assess both anatomical morphology and cell metabolism in one single examination. Long term follow-up is necessary.