[History and Present of Stereotactic and Functional Neurosurgery]

Stereotactic and functional neurosurgery(SFN)is one of the oldest subspecialties of neurosurgery. In Japan, functional epilepsy surgery was performed in the Meiji era, even before World War II, when general surgeons used to operate on patients with intractable cancer pain through open myelotomy or cordotomy. Knowledge gathered from such age-old procedures provided the basic understanding of neurophysiology and hence, functional neurosurgery used to be termed as "applied neurophysiology". Human stereotactic surgery was introduced in 1947 and many Japanese neurosurgeons, particularly Hirotaro Narabayashi, Keiji Sano and Chihiro Ohye, contributed to the development of this field. Additionally, we should remember that common procedures of neurosurgery practiced today such as neuroendoscopy, navigation surgery, intraoperative monitoring, and the concept of exo-scope, which are less invasive and involves high accuracy, emerged from the field of SFN. Young doctors should learn from history and understand where we started from, where we at present, and where we are heading in the future.