Purpose: To report the optical coherence tomographic features differentiating choroidal nevus from choroidal melanoma by 3D spectral-domain optical coherence tomography (SD-OCT) and OCT characteristics of other choroidal tumors.
Methods: A total of 67 consecutive eyes with choroidal tumors including choroidal nevus (25 eyes), indeterminate choroidal melanocytic lesion (11 eyes), malignant melanoma (23 eyes), metastasis (4 eyes), hemangioma (2 eyes), and osteoma (2 eyes) were imaged with 3D SD-OCT (OCT-1000; Topcon Inc., Paramus, NJ). The images were analyzed for the presence or absence of SD-OCT findings such as retinal pigment epithelium (RPE)/choriocapillaris reflectivity, RPE irregularity, drusen, sub-RPE fluid, RPE thickness, subretinal deposit, subretinal fluid, intraretinal edema, retinal thickness, and photoreceptor inner and outer segment junction (IS/OS). Visualization of the choroidal tumor and its intrinsic reflectivity OCT features were also assessed.
Results: When compared with nevus, subretinal deposit, subretinal fluid, and intraretinal edema were detected significantly more frequently in the eyes with malignant melanoma (p<0.001). SD-OCT visualization of the tumor was limited only to the anterior aspect. Choroidal nevus, indeterminate lesions, melanoma, and metastatic lesions had variable intrinsic reflectivity pattern. Intrinsic features of hemangioma included choroidal hollowness whereas osteoma demonstrated high intrinsic reflectivity.
Conclusions: SD-OCT provides useful information to observe and document the retinal and RPE changes secondary to choroidal tumors that help differentiate choroidal nevus from malignant melanoma. Improvements in the current OCT systems are needed to better characterize intrinsic features of choroidal tumors.