Gamma-Knife Radiosurgery in Patients with Optic Nerve Sheath Meningeoma (ONSM)
Klein A.1, Müllner K.1, Feichtinger K. H.2, Papaefthymiou G.2, Langmann G.1
1Universtäts-Augenklinik Graz, 2Universitätsklinik für Neurochirurgie Graz
Purpose: We evaluated the effectiveness of Radiosurgery with the Gamma Knife in the treatment of ONSMs.
Method: Five patients with ONSMs, were treated at the University Hospital of Graz, with the Gamma Knife between 1992 and 2001 and received a tumour margin dose of 14 to 25 Gy.
Results: With a median follow up of 52 months, a response to the radiosurgery with the Gamma Knife, documented by MRI, could be achieved in all five patients. Four of the five patients had surgery before the Gamma Knife treatment. Two of these preoperated patients had no light perception after surgery. One of them had to be enucleated due to amotio insanata. In the case with the highest dosage of 25 Gy, an amaurosis occurred due to a vessel occlusion. The patient, who had been not operated before, could be stabilized in his visual acuity, visual field and electrophysiological response.
Conclusions: Radiosurgery with the Gamma Knife is an alternative treatment modality for ONSMs. A further study with a higher number of patients is necessary to evaluate whether a reduction of dosage can lead to an increase of visual acuity.
Zurück | Back