The B-mode ultrasonic appearance of eyes afflicted with retinopathy of prematurity exhibiting leukokoria was retrospectively investigated as an aid to increase the accuracy in assessing the patient with leukokoria. B-mode sonograms were obtained employing the immersion technique (Sonometrics 150 A/B-mode instrument). Contact A-mode confirmation was made (Kretztechnik 7200 MA instrument). Prominent B-mode characteristics included echo patterns consistent with increased corneal thickness (47%), shallow anterior chamber depth (73%), malpositioned lens (64%), cataractous lens changes (64%), fibroproliferation in the anterior vitreous (63%), total retinal detachment (53%), partial retinal detachment and/or retinal fold (30%), choroidal thickening (30%), and acoustic shadowing of orbital fat (33%). Together, these features aid in the ultrasonic differentiation from other causes of leukokoria.