The Lateral Triangle of the Middle Fossa: Surgical Anatomy and a Novel Technique for Transcranial Exposure of the Internal Maxillary Artery

Authors

Xuequan Feng, Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.
Michael T. Lawton, Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.Follow
Jordina Rincon-Torroella, Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland.
Ivan H. El-Sayed, Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.
Ali Tayebi Meybodi, Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.
Arnau Benet, Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.Follow

Document Type

Article

Abstract

BACKGROUND: The challenge of locating and isolating the internal maxillary artery (IMA) hinders its potential use as an arterial donor for extracranial-to-intracranial bypass surgery. OBJECTIVE: To introduce a new approach through the middle cranial fossa for easy access and safe exposure of the IMA. METHODS: Ten specimens were prepared for surgical simulation. After the pterional craniotomy, a 2-step drilling technique was performed (lateral triangle). First, a triangular craniectomy was completed anterolateral to the foramen spinosum. By following the middle meningeal artery and dividing the lateral pterygoid muscle, the proximal part of IMA was located. Second, a bone slot was drilled in a posterior-to-anterior direction from the anterior aspect of the first craniectomy. By tracing of the proximal part, the main trunk of the IMA was obtained. The size of the 2 craniectomies, the depth of IMA from the surface of the middle fossa, and the length of exposed IMA were measured. RESULTS: Drilling within the lateral triangle allowed safe exposure of both the trunk and the branches of the mandibular nerve of the IMA. The total craniectomy measured 27.8 ± 4.2 mm in the anterior-posterior direction, and the posterior portion measured 13.3 ± 1.5 mm in the lateral-medial direction. The depth from the middle fossa to the IMA (16.8 ± 3.2 mm, mean ± SD) was equal to the length of IMA exposed (17.6 ± 3.3 mm, mean ± SD; P > .05). CONCLUSION: This new approach provides an efficient and safe method to consistently find and isolate a segment of the IMA suitable for extracranial-to-intracranial bypass.

Publication Date

6-1-2016

Publication Title

Operative neurosurgery (Hagerstown, Md.)

E-ISSN

2332-4260

Volume

12

Issue

2

First Page

106

Last Page

111

PubMed ID

29506088

Digital Object Identifier (DOI)

10.1227/NEU.0000000000001099

Recommended Citation

Feng, Xuequan; Lawton, Michael T.; Rincon-Torroella, Jordina; El-Sayed, Ivan H.; Meybodi, Ali Tayebi; and Benet, Arnau, "The Lateral Triangle of the Middle Fossa: Surgical Anatomy and a Novel Technique for Transcranial Exposure of the Internal Maxillary Artery" (2016). Neurosurgery. 1259.
https://scholar.barrowneuro.org/neurosurgery/1259