In spite of the recent and substantial improvements in MR technique, some problems still exist relative to its applications in routine clinical exams in pediatric ophthalmology. The main problems are: inadequate MR equipment, long examination time, and MR inability to demonstrate intraocular calcifications. Ocular and orbital ultrasound (US) studies are highly operator-dependent, and US utility has been especially described in evaluating ocular, but not orbital, lesions. In order to verify the actual role of CT in pediatric ophthalmology, the CT scans of 58 children with ophthalmologic pathologies, performed over a 2-year period, were reviewed and compared with definitive diagnoses. Seven separate CT findings for each pathologic condition were independently analyzed and correlated with histology. In agreement with other CT series, optic nerve gliomas were invariably intraconal, whereas histiocytosis-X, Ewing's sarcoma, olfactory neuroblastoma (esthesioneuroblastoma), metastatic neuroblastoma and nephroblastoma were extra-conal. Rhabdomyosarcoma, principally extraconal, frequently involved the intraconal and preseptal spaces, with permeative destruction of the osseous orbit and frequent intra/extracranial spread. Orbital spread was mainly observed in vascular tumors. CT showed great accuracy in evaluating punctuate calcifications in retinoblastomas and in metastatic neuroblastomas, and bone fragments within a zone of destruction in histiocytosis-X. Various characteristics of CT attenuation values were observed in pathologic tissues, and high attenuation and marked contrast enhancement were particularly observed in metastatic neuroblastomas and rhabdomyosarcomas. In congenital orbital abnormalities and inflammatory diseases, CT readily detected ocular malformations (microphthalmos and colobomata).(ABSTRACT TRUNCATED AT 250 WORDS)