[Stereotaxic technics and clinical neurosurgery]

Stereotactic methodology developed at Sainte-Anne Hospital Center from 1947 is based on the application of a simple spatial geometry-the Talairach Ac-Pc reference system-to the cranial volume and the identification of any anatomical structure or brain lesion within this volume. Now upgraded with modern imaging techniques, this methodology is the ground for multiple applications in functional as well as lesional neurosurgery and is now a a part of the daily neurosurgical practice at Sainte-Anne Hospital. Stereotactic procedures include three steps: first, the identification of one or several target-volumes through stereotactic imaging acquisition: CT, MRI and conventional stereoscopic angiography; second, the image treatment on a dedicated workstation for stereotactic coordinates determination and surgical planning; third, the surgical procedure itself and its control. The most frequent applications for stereotactic methodology are: image-guided stereotactic biopsies of brain tumors, in order to obtain tissue pathological diagnosis and spatial configuration; linac-based radiosurgery of arterio-venous malformations and tumors with high energy collimated beams converging towards a simple or complex target volume; surgery for partial drug-resistant epilepsy including depth electrode implantation for stereo-electroencephalography and epileptogenic cortex resection; stereotactic image-guided resection of superficial or deep-seated tumors or vascular malformation; Rhenium 186 intracavitary irradiation of cystic tumors such as craniopharyngiomas.