title: Endoscope-Assisted Microsurgical Approach to the Posterior and Posterolateral Incisural Space.
abstract: OBJECTIVE
  Despite recent technological advances, direct approaches to the posterolateral incisural space remain surgical challenges. The choice of the operative route depends on the exact location and extent of the target lesion as well as individual preferences. The extreme lateral infratentorial supracerebellar approach to treat pathologies located in the ambient cistern and posterior incisural space is a technically feasible route in selected cases. In this cadaveric study, we demonstrate the benefits of endoscope-assisted microsurgical maneuvers using the extreme lateral supracerebellar infratentorial approach.
  
  
  METHODS
  An endoscope-assisted infratentorial supracerebellar approach was performed in six formalin-fixed cadaveric heads using standard microneurosurgical methods. Dissections were performed in a stepwise fashion, comparing the exposure afforded by the microsurgical route alone to the endoscope-assisted route, using 0- and 30-degree angled lenses. Relationships among the target and the surroundings neurovascular structures were described.
  
  
  RESULTS
  Endoscope-assisted maneuvers for the extreme lateral supracerebellar approach provide an improved operative view and have the potential to reduce parenchymal trauma and neurovascular injuries. The endoscopic techniques bring the surgeon to the anatomy, enhancing illumination and surgical visualization.
  
  
  CONCLUSIONS
  Direct visualization of the posterior and posterolateral incisural space avoids retraction of the occipital lobe and damage to the deep venous complex. The extreme lateral infratentorial supracerebellar corridor is effective for approaching the posterolateral mesencephalic junction and the posterior incisural space in selected cases. Endoscope-assisted microsurgery can improve visualization and minimize parenchymal retraction, which should enhance surgical control.
authors.affiliation: Department of Neurosurgery, Boston Children's Hospital, Harvard Medical School, Cambridge, Massachusetts, USA. Electronic address: Roberta.Rehder@childrens.harvard.edu.
authors.forename: Roberta
authors.initials: R
authors.lastname: Rehder
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts, USA.
authors.forename: Marcos Perocco
authors.initials: MP
authors.lastname: Luiz da Costa
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts, USA.
authors.forename: Ossama
authors.initials: O
authors.lastname: Al-Mefty
authors.affiliation: Department of Neurosurgery, Boston Children's Hospital, Harvard Medical School, Cambridge, Massachusetts, USA.
authors.forename: Alan R
authors.initials: AR
authors.lastname: Cohen
mesh_terms: D000328:Adult; D001921:Brain / Q000601:surgery*; D002102:Cadaver; D006801:Humans; D008866:Microsurgery / Q000379:methods*; D044583:Neuroendoscopy / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*
keywords: Anatomy; Endoscopy; Extreme lateral approach; Infratentorial supracerebellar approach; Microsurgery; Posterior incisural space