Endoscopic minimally invasive neurosurgery: emerging techniques and expanding role through an extensive review of the literature and our own experience - part I: intraendoscopic neurosurgery.

BACKGROUND/AIMS: Minimally invasive neurosurgery is a growing field, more so in recent decades. The modernization of tools, especially the endoscope, has allowed for critical improvements and crucial advancements in minimally invasive neurosurgery. The current classification scheme for endoscopic procedures needs to be updated to reflect these advancements. METHODS: Although the field of neuroendoscopy is continually evolving, the terminologies utilized to describe endoscopic procedures reflect and favor its use as mostly an assisting device complementing the microscope. Even though the classification was adequate for its time, it has become inexact and therefore confusing. We therefore propose a new classification scheme that encompasses the growing independence of endoscopic minimally invasive neurosurgery (EMIN) as well as the changing landscape within EMIN procedures. RESULTS: We have classified our EMIN procedures, since 2002, as either 'intraendoscopic' (IEN) or 'extraendoscopic' (XEN) in relation to the endoscope's axis. Exemplary cases of IEN and a review of the literature are presented as well. CONCLUSION: Our proposed classification scheme for solely endoscopic procedures is presented. The role of the endoscope as an independent tool is clarified.

Endoscopic minimally invasive neurosurgery: emerging techniques and expanding role through an extensive review of the literature and our own experience - part II: extraendoscopic neurosurgery.

BACKGROUND/AIMS: The field of minimally invasive neurosurgery has grown dramatically especially in the last decades. This has been possible, in the most part, due to the advancements in technology especially in tools such as the endoscope. The contemporary classification scheme for endoscopic procedures needs to advance as well. METHODS: The present classification scheme for neuroendoscopic procedures has become confusing because it mainly describes the use of the endoscope as an assisting device to the microscope. The authors propose an update to the current classification that reflects the independence of the endoscope as a tool in minimally invasive neurosurgery. RESULTS: The proposed classification groups the procedures as 'intraendoscopic' neurosurgery or 'extraendoscopic' neurosurgery (XEN) in relation to the 'axis' of the endoscope. A review of the literature for the XEN group together with exemplary cases is presented. CONCLUSION: We presented our proposed classification for the endoscope-only surgical procedures. The XEN group is expanded in this article.