In the literature, there are reports in which clinical misinterpretation of posterior scleritis as choroidal melanoma has led to therapeutic misdirection, including enucleation. It is important to recognize the distinguishing features between posterior scleritis and choroidal melanoma. It is noteworthy that our patient had no symptoms or associated collagen vascular disease. The only finding was nonpigmented fundus mass with minimal subretinal fluid. We believe that the nonpigmented appearance of the lesion, normal intrinsic choroidal vascular pattern, and transmission of light on transillumination were important clinical clues suggestive of posterior scleritis.
Ancillary tests can be helpful in the diagnosis of posterior scleritis.
Ultrasonography generally reveals an echogenic mass with echo-free retrobulbar edema. In equivocal cases, biopsy can be revealing but it should be understood that biopsy of a transcleral mass can be hazardous and it should be reserved for selected diagnostic problems. Systemic, retrobulbar, or topical corticosteroids are generally recommended for symptomatic posterior scleritis. The natural history of posterior scleritis is characterized by intermittent pain, swelling, and even scleral necrosis, but our case is unique in that the massive lesion has remained stable during 12 years of observation. Despite growing clinical experience and advances in imaging techniques, differentiation between posterior scleritis and malignant melanoma can be a challenge.