In the presence of leukokoria the diagnosis of retinoblastoma is usually easy when the mediae are transparent. If they are not, however, one is frequently obliged to enucleate a painful or useless eye in order to rule out this diagnosis. In a series of eight cases having undergone enucleation for this reason at the Lausanne University Eye Hospital, the histological examination revealed four pseudogliomas. These particularly instructive cases are described, together with the histological findings.