[The question of midface growth inhibition following retinoblastoma treatment in early childhood].

99 patients treated for bilateral retinoblastomas in the University Hospital of Essen between 1965 and 1983 were followed up for midface growth inhibition for an average period of 15 1/2 years. Depending on the type of treatment employed the patients were divided into four groups: Local tumor treatment using cryotherapy or laser techniques, ophthalmectomy alone, radiotherapy alone, and combined ophthalmectomy and radiotherapy. Statistically significant differences between the treatment groups were found regarding such symptoms as hypoplasia of the zygomatic bone, hypoplasia of the transversal orbit, hypoplasia of the temporal fossa, hypoplasia of the root of the nose as well as hypotelorism and enophthalmos. Combined surgery and radiotherapy caused the most severe growth disorders, followed by radiotherapy alone and ophthalmectomy alone. With local treatment detectable growth disorders were observed, if at all, only as a result of contralateral radiation scatter. Orthovoltage radiotherapy was found to produce growth disorders of significantly higher severity than megavoltage radiotherapy.