Optical coherence tomography in diagnosing, differentiating and monitoring of choroidal nevi - 1 year observational study.

OBJECTIVE To assess the utility of the optical coherence tomography (OCT) in diagnosing, differentiating and monitoring of choroidal nevi situated in the posterior pole and optic disc area. MATERIAL AND METHOD 116 consecutive patients (65 women, 51 men) aged 27-95 years, with choroidal nevus were included to the research. Routine ophthalmoscopic evaluation and OCT using the Zeiss Stratus OCT as well as fundus photography were performed in each patient. The OCT was used to assess the structure of the retina overlying the choroidal nevus, the retinal pigment epithelium (RPE) - choriocapillaris complex, as well as the anterior portion of the choroidal lesion. In 31 patients due to suspected malignant melanoma fluorescein angiography and ultrasound were additionally performed. Follow-up OCT was done after 12 months in 51 out of 85 patients with characteristics of choroidal nevi, and after 6 and 12 months in 27 patients with "suspicious" lesion. RESULTS The basal dimension of the lesion ranged from 0.5 mm to 12 mm (mean 2.75mm), mean thickness was 1.25 mm. The pigmented lesion did not affect visual acuity. In 85 patients the lesion was flat or slightly elevated, without secondary changes in the retina. In 31 patients additional changes in the retina were observed - most frequently subretinal fluid. Two patients were eventually diagnosed with malignant melanoma. The follow-up OCT did not show progression in neither patients without secondary changes nor those with risk factors of malignancy. CONCLUSION Optical coherence tomography enables detailed evaluation of the retina overlying the pigmented lesion. Secondary changes in the retina need additional exams and strict observation. OCT could be an additional tool in the evaluation of treatment of malignant melanoma.