The EOG and choroidal malignant melanomas.

Fifty-four patients with a unilateral pigmented choroidal lesion were studied with electrooculography (EOG). Eighteen of 21 patients with histologically proven (13) or presumed (8) malignant tumors of the choroid had light peak-dark trough ratios (L/D) less than or equal to 150. Seventeen of 21 patients in the malignant group had an interocular L/D difference (L/Dd) greater than or equal to 23%, whereas only one of 33 patients with nevi or a condition simulating a nevus had a percent difference of such magnitude. Combining the L/D and L/Dd criteria resulted in a 98% accurate double-blind prediction of the final clinical/pathological results. The EOG is an objective, noninvasive test useful in the diagnosis of choroidal malignant melanomas.