Optical coherence tomography of choroidal nevus in 120 patients.

OBJECTIVE

To describe the optical coherence tomography (OCT) findings of choroidal nevi.

METHODS

Retrospective, single-center case series of 120 eyes of 120 consecutive patients with choroidal nevi who were evaluated by OCT. Diagnostic imaging was performed with a Zeiss StratusOCT Model 3000 (Carl Zeiss Ophthalmic Systems, Dublin, CA) using scan acquisition protocols of 6 radial lines and retinal thickness analysis overlying the nevus.

RESULTS

The mean patient age was 59 years (median, 60 years; range, 14-87 years). The choroidal nevus was a mean of 5.2 mm in basal dimension and 1.7 mm in thickness and was located a mean of 2.7 mm from the optic disk and 2.5 mm from the foveola. Related retinal findings by ophthalmoscopic evaluation included overlying retina edema (3%), subretinal fluid (16%), retinal thinning (0%), drusen (58%), and retinal pigment epithelium (RPE) detachment (2%). In comparison, related retinal findings at the site of the nevus by OCT included overlying retina edema (15%), subretinal fluid (26%), retinal thinning (22%), drusen (41%), and RPE detachment (12%). Furthermore, OCT permitted classification of the overlying retinal edema as focal cystoid (3%), diffuse cystoid (8%), coalescent cystoid (3%), and noncystoid edema (1%). By OCT, the overlying retina was normal thickness (32%), thinned (22%), or thickened (45%), and photoreceptor loss or attenuation was noted in 51% of cases. Specific OCT findings of the choroidal nevus were limited to its anterior surface with minimal penetration into the mass. These findings included increased thickness of the RPE/choriocapillaris layer (68%) and optical qualities within the anterior portion of the nevus of hyporeflectivity (62%), isoreflectivity (29%), and hyperreflectivity (9%). Hyporeflectivity was observed in 68% of pigmented nevi and 18% of nonpigmented nevi. When comparing OCT with clinical examination, OCT was more sensitive in the detection of related retinal edema, subretinal fluid, retinal thinning, photoreceptor attenuation, and RPE detachment.

CONCLUSIONS

OCT is a useful diagnostic modality for imaging the retina overlying a choroidal nevus. Numerous overlying changes such as subretinal fluid, retinal edema, retinal thinning, and photoreceptor attenuation are visible by OCT.