On a group of 60 children the authors demonstrate the possibility to use ultrasound in the differential diagnosis of some intraocular expansive processes. In retinoblastoma the diagnostic accuracy of ultrasound was 85.7%. Decisive in this respect is the detection of calcifications, which, consistent with data in the literature, was 78.5%. Calcifications were not detected in pseudogliomas and retinopathies of premature infants, structures in the vitreous body were less echogenic and separated from the retina. Ultrasound made it possible in all instances to evaluate satisfactorily the extent of changes in the vitreous body and contributed thus to the selection of the therapeutic procedure. The authors describe also two rare conditions--Coats's disease and persistence of a hyaloid artery.