Utility of pupillary dilation for detecting leukocoria in patients with retinoblastoma

In the United States, 50% of all retinoblastoma cases are diagnosed after t he observation of leukocoria by a family member or primary care physician. However, leukocoria produced by retinoblastoma lesions can often be missed by direct ophthalmoscopic examination through an undilated pupil. The purpo se of this study is to demonstrate the utility of pupillary dilation for th e detection of leukocoria in suspected cases. Seven patients (10 eyes), age d 2 days to 20 months, with retinoblastoma were examined for leukocoria usi ng a direct ophthalmoscope with the pupils first undilated and then after p harmacologic dilation with 0.5% cyclopentolate and 2.5% phenylephrine. Leuk ocoria was detected by direct ophthalmoscopy on undilated examination in 3 of 10 eyes (30%). In contrast, leukocoria was observed after pupillary dila tion in 10 of 10 eyes (100%). The retinoblastoma lesions, from 2 to 10 mm i n diameter, were located within the posterior 45 degrees of the retina. Pup illary dilation is a safe and effective tool that can enhance the ability o f the examiner to detect leukocoria. Dilation may afford early diagnosis an d treatment, and therefore should be considered on patients in whom the dia gnosis of retinoblastoma is entertained.