[Typical and atypical ultrasonic forms of retinoblastoma]

Ultrasonographic examination of leukokoria has proved useful to demonstrate the presence of an intraocular mass and to confirm a suspected retinoblastoma. However, some retinoblastomas present atypical clinical and ultrasonic appearances leading to errors in diagnosis. The ultrasonic characteristics of the two classic types, are presented, together with a third type in which the appearance is diffuse or pseudoinflammatory, one case having been previously misdiagnosed as sub-clinical endophthalmitis. The different characteristics of the three types and their relationship with histologic forms are discussed.