The neurosurgeon's perspective

Stereotactic radiosurgery, a term introduced by Leksell, was born more than 40 years ago, but has made great strides for the last 15 years. There is no consensus among neuro-surgeons as to the best device (gamma knife, linear accelerator), the treatment doses, and the clinical indications of stereotactic radiosurgery. Therefore, this report is the viewpoint of one neurosurgical team only. In the radiosurgery literature, there is no clear evidence of better results with the gamma-knife or the linear accelerators. With regard to clinical applications, cerebral arteriovenous malformations are the more widely accepted indications of radiosurgery, since a cerebral angiography can confirm the disappearance of the nidus of an arteriovenous malformation treated by stereotactic radiosurgery. Usually, small and deep arteriovenous malformations can be treated by stereotactic radiosurgery only. Nevertheless, the treatment of the other arteriovenous malformations more often require procedures including one or several of the following treatment methods: micro-neurosurgery, interventional neuroradiology, stereotactic radiosurgery. Stereotactic radiosurgery in acoustic schwannomas, skull base meningiomas, especially those involving the cavernous sinus, brain metastases, and pituitary tumors seem attractive. Contrary to arteriovenous malformations, the lack of criteria for cure requires a long follow-up and carefully controlled trials to confirm the efficiency of stereotactic radiosurgery for these tumors. On the other hand, experience of stereotactic radiosurgery for astrocytomas and glioblastomas is limited, and few publications are available. Furthermore, because of the infiltrating growth, a major impact of stereotactic radiosurgery for these tumors is presumably not to be expected. Lastly, a close multidisciplinary approach seems absolutely necessary to define the best indications of stereotactic radiosurgery and to improve its clinical results. (authors)