Prospects and future: evolution of stereotactic methodology for planning

We, have been using the stereotactic methodology of Talairach for Linac rad iosurgery of cerebral al arteriovenous malformations since 1984, and update d it with addition of CT and MR images into the stereotactic space. The tar get remains defined as in most other centers, by stereotactic angiography. However, tridimensional configuration of cerebral arteriovenous malformatio ns is better defined using MR or CT-angiography. Therefore, pre-radiosurgic al imaging tends to combine multimodal images oriented into the stereotacti c space. Frame-based radiosurgery, with invasive frame placement, will be r eplaced in the future by frameless irradiation with real-time tracking of t he patients head, as performed by the recently described Cyber-knife. Intra operative X-ray will be no longer long-distance fired equipments but mobile , short-distance fluoroscopic systems integrated in the surgical workstatio n environment. Finally, biplane conventional angiography performed for cere bral arteriovenous malformations identification will be replaced by CT and MR-angiography, except in some cases who could still require DSA for accura te target identification.