title: The supraorbital keyhole approach to supratentorial aneurysms: concept and technique.
abstract: BACKGROUND
  Anterior surgical approaches to the base of the brain have always required relatively large craniotomies, most larger than the lesion itself. Especially in aneurysm surgery, the size of the lesion is not always proportionate to the extent of brain exposure. The improvement of surgical techniques and diagnostic imaging, as well as the introduction of neuroendoscopy and new surgical instruments, enable us now to treat various intracranial lesions through small keyholes. In particular, cerebral aneurysms, because of their anatomic characteristics, are apt to be treated by the keyhole approach. The supraorbital keyhole approach has the broadest field of indications, although its technical aspects have not yet been evaluated.
  
  
  METHODS
  The concept and technique of the supraorbital keyhole approach are presented in detail. We conducted a retrospective study in which we evaluated the technical aspects of the supraorbital keyhole approach considering the indications, limitations, and complications of this approach as well as new instrumentation in surgery of supratentorial aneurysms.
  
  
  RESULTS
  The use of 139 supraorbital keyhole approaches for 197 aneurysms is described. Multiple aneurysms have been treated by one approach in 38 patients. Clipping of the aneurysm was performed in 94% and wrapping in 6% of patients. Eighteen aneurysms were contralateral to the approach. In four patients, intraoperative accidental aneurysm rupture occurred. There were no approach-related complications.
  
  
  CONCLUSIONS
  The supraorbital keyhole approach offers equal surgical possibilities with less intraoperative accidental rupture and less approach-related morbidity as conventional approaches in the treatment of supratentorial aneurysms.
authors.affiliation: Department of Neurosurgery, Johannes Gutenberg University, Mainz, Germany.
authors.forename: E
authors.initials: E
authors.lastname: van Lindert
authors.forename: A
authors.initials: A
authors.lastname: Perneczky
authors.forename: G
authors.initials: G
authors.lastname: Fries
authors.forename: E
authors.initials: E
authors.lastname: Pierangeli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003399:Craniotomy / Q000379:methods*; D004388:Dura Mater; D004724:Endoscopy; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009915:Orbit; D014656:Vascular Surgical Procedures / Q000379:methods*