Incidence of misdiagnosed and unsuspected choroidal melanomas. A 50-year experience.

The eye pathology files at Ohio State University, Columbus, were examined for a 50-year period to determine the percentage of misdiagnosis of uveal melanomas in three separate time periods (1931 through 1959, 1960 through 1969, and 1970 through 1981) and the percentage of unsuspected melanomas during these same periods. Of 395 eyes enucleated for choroidal melanoma, 369 had clear media. Histologic examination of these eyes showed that 13 (3.5%) did not contain a melanoma. The incidence of misdiagnosis decreased from 10.9% in 1931 through 1959 to 1.7% in 1960 through 1981. Of 411 choroidal melanomas present on histologic examination, 37 (9%) were unsuspected. All had opaque media. This percentage, when categorized by the aforementioned periods, decreased from 19.6% to 13.3% to 2.4%, respectively. These results confirm the reliability of indirect ophthalmoscopy, widely used since the 1960s, in the diagnosis of melanoma in the presence of clear media and the reliability of ultrasonography, used since 1970, in the diagnosis of melanoma in eyes with opaque media.