Long-term echographic surveillance of elevated choroidal nevi

To report the outcomes of choroidal nevi monitoring and to compare the detection of ultrasonographic hollowness, a risk factor of malignant transformation, from a B-scan with results from an A-scan examination.

Retrospective cohort study.

Standardized A- and B-scan echography and ophthalmoscopy in 358 consecutive patients with median age 69 years and baseline choroidal nevus higher or lower than 1.5 mm in 51 (14%) and 307 (86%) eyes, respectively.

No growth or change in echographic or ophthalmoscopic features were found in 307 nevi with a median elevation of 0.9 mm (range, 0.7 to 1.5 mm) and a median follow-up of 6 years (range, 4 to 9 years). After 2 to 6 years, decreased internal reflectivity on standardized A-scan and ultrasonographic hollowness on B-scan were detected in 7 (18%) of 38 initially highly reflective choroidal nevi (thickness, 1.98 ± 0.37 mm); 2 (5%) nevi grew into melanoma 15 years after the first observation. Of 13 choroidal nevi (thickness, 2.75 ± 0.66 mm), with initial atypical medium to high reflectivity on standardized A-scan (100%) and hollowness on B-scan (85%), 6 (46%) were plaqued 6 to 15 months later because of the presence of multiple risk factors.

No changes in thickness or echographic features of choroidal nevi elevated up to 1.5 mm were recorded during the follow-up period. In initially typical choroidal nevi higher than 1.5 mm, strong agreement was detected between decreased reflectivity on standardized A-scan and ultrasonographic hollowness on B-scan found after up to 15 years of stability. The vast majority of choroidal nevi with initial atypical standardized A-scan features showed ultrasonographic hollowness.