The techniques of stereotactic surgery are utilized in some functional procedures (e.g. DBS) as well as for biopsies (see Stereotactic biopsy) cyst drainage, etc. The term stereotactic (Greek: stereo = 3-dimensional, tactic = to touch) surgery was initially used in animals, and was based on atlases of three-dimensional coordinates compiled from dissections. The term was then used for surgery performed in humans, usually for thalamic lesioning to treat Parkinsonism, see Parkinson's disease surgery, where the target site to be lesioned was located relative to landmarks with intraoperative pneumoencephalography or contrast ventriculography. Use of this procedure fell off dramatically in the late 1960s with the introduction of L-dopa for Parkinsonism 1)
Current techniques would be more appropriately termed image-guided stereotactic surgery.