Skull Base 2006; 16(3): 181-184
DOI: 10.1055/s-2006-939676
TECHNICAL NOTE

Copyright © 2006 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Extradural Middle Fossa Approach. Proposal of a Learning Method: The “Rule of Two Fans.” Technical Note

Luciano Mastronardi1 , Tetsuro Sameshima2 , 3 , Alessandro Ducati4 , Luc F. De Waele5 , Luigi Ferrante1 , Takanori Fukushima6 , 7 , 8
  • 1Department of Neurosurgery, University La Sapienza, S. Andrea Hospital, Rome, Italy
  • 2Department of Neurosurgery, Duke University, Durham, North Carolina
  • 3Department of Neurosurgery, Miyazaki Medical University School of Medicine, Miyazaki, Japan
  • 4Department of Neurosurgery, University of Torino, Le Molinette Hospital, Torino, Italy
  • 5Department of Neurosurgery, Sint-Lucas Hospital, Ghent, Belgium
  • 6Carolina Neuroscience Institute for Skull Base Surgery, Raleigh, North Carolina
  • 7Duke University, Durham, North Carolina
  • 8University of Morgantown, Morgantown, West Virginia
Further Information

Publication History

Publication Date:
03 May 2006 (online)

ABSTRACT

The extradural middle fossa approach is used to access lesions of the petroclival and cavernous sinus regions. It may be included in combined petrosal and anterolateral transcavernous approaches. Technically, it is a demanding exposure that provides a wide extradural corridor between the 5th, 7th, and 8th cranial nerves. Its major advantages are that it offers extradural dissection, limits temporal lobe retraction, and avoids the transposition of nerves or vessels. Its disadvantages are primarily related to the complicated anatomy of the petrous apex from the middle fossa trajectory, which can be unfamiliar to neurosurgeons. To facilitate the first attempts with this relatively uncommon approach during dissections of human cadaveric injected heads and isolated temporal bones, we developed a simple learning method useful for localizing all anatomical structures. Using this “rule of two fans,” vascular, nervous, fibrous, and osseous structures are localized within two bordering fans with a 90-degree relationship to each other.

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Luciano MastronardiM.D. Ph.D. 

Via Reno 14, 00198 Rome, Italy

Email: maestro@tin.it