title: Frontotemporal orbitozygomatic craniotomy to exposure the cavernous sinus and its surrounding regions. Microsurgical anatomy.
abstract: BACKGROUND
  The microsurgical anatomy of the cavernous sinus and its surrounding regions were examined via frontotemporal orbitozygomatic (FTOZ) craniotomy. Combined with other deep osteotomies, the possibility of exposing the petroclival region and basilar artery was also explored.
  
  
  METHODS
  The study was made on 20 sides of 10 cadaveric specimens fixed with formalin, with the help of the surgical microscope (magnification 5-15).
  
  
  RESULTS
  The FTOZ was performed with frontotemporal and orbitozygomatic flaps. Extradurally, V2, V3, the trigeminal ganglion, the posterior vertical segment of the intracavernous ICA and the VI nerve were exposed by FTOZ craniotomy. By further removal of the petrous apex (Kawase's triangle), exposure could be extended to the petroclival region; with anterior modification of the microscopic light, in 50% of the specimens, exposure reached as low as the convergence of the vertebral arteries. The anterior part of the cavernous sinus and the orbital apex were examined by removing the anterior clinoid process, orbital roof and unroofing the optic canal. Intradurally, the intrapeduncular fossa (upper 1/3 of the clivus) was examined. The intracavernous cranial nerves and vessels were studied via lateral and superior wall approaches. By removing both the anterior and posterior clinoid processes together, in 80% of the specimens, the exposure could be carried as far as the midpoint of the basilar artery.
  
  
  CONCLUSIONS
  FTOZ craniotomy could be used to treat lesions involving the cavernous sinus and its surrounding regions. Incorporated with the petrous apectomy, it could be used to expose the petroclival region and, in selected cases, exposure could be extended to the convergence of the vertebral arteries. Combined with anterior and posterior clinoidectomies, it could also be used to treat midpoint regions of the basilar artery.
authors.affiliation: Department of Neurosurgical Sciences, Neurosurgery I, University La Sapienza, Rome, Italy.
authors.forename: F Z
authors.initials: FZ
authors.lastname: Jian
authors.forename: A
authors.initials: A
authors.lastname: Santoro
authors.forename: G
authors.initials: G
authors.lastname: Innocenzi
authors.forename: X W
authors.initials: XW
authors.lastname: Wang
authors.forename: S S
authors.initials: SS
authors.lastname: Liu
authors.forename: G
authors.initials: G
authors.lastname: Cantore
mesh_terms: D001488:Basilar Artery / Q000033:anatomy & histology / Q000601:surgery; D002426:Cavernous Sinus / Q000033:anatomy & histology / Q000601:surgery*; D003391:Cranial Nerves / Q000033:anatomy & histology / Q000601:surgery; D003399:Craniotomy / Q000379:methods*; D005624:Frontal Bone / Q000601:surgery; D006801:Humans; D008866:Microsurgery / Q000379:methods; D009915:Orbit / Q000033:anatomy & histology / Q000601:surgery*; D013701:Temporal Bone / Q000601:surgery; D015050:Zygoma / Q000033:anatomy & histology / Q000601:surgery*