Fractionated irradiation of meningiomas of the optic nerve: the average ocular dose is a predictive factor of the visual function future

As radiotherapy is efficient in terms of tumour growth control in the case of optic nerve meningiomas and allows a stabilization of visual acuity, but as radio-induced toxicity may threaten the functional benefit, the authors report a study which aimed at identifying predictive factors of a pejorative evolution of the visual function for patients submitted to radiotherapy for an optic nerve meningioma. Files of ten patients have been analyzed in terms clinical, radiological and dosimetric aspects. Visual acuity and visual field before and after conformational radiotherapy have been compared by means of the Wilcoxon Rank test. It appears that the visual function future can be threatened by irradiation side effects. Short communication