Anterolateral Triangle: A Cadaveric Study with Neurosurgical Significance.

Cureus. 2018 Feb 12;10(2):e2185. doi: 10.7759/cureus.2185.

Granger A, Bricoune O, Rajnauth T, Kimball D, Kimball H, Tubbs RS, Loukas M.

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Abstract

The anterolateral triangle is one of 10 surgical triangles of the cavernous sinus and serves as an important anatomic landmark for the skull base surgeon. There are few studies in the English literature that have precisely defined and measured the borders of the anterolateral triangle and little agreement has been made regarding the nomenclature within the English literature. A total of 12 midsagittally hemisected adult human cadaveric head halves were dissected to expose the anterolateral triangle. The triangle was defined and measurements of the anterior, posterior, and lateral borders were taken. The mean lengths and standard deviations of the anterior, posterior, and lateral borders were 8.3 ± 2.2 mm, 5.9 ± 2.0 mm, and 11.5 ± 2.9 mm, respectively. The mean area and standard deviation were 20.46 ± 9.30 mm2. The anterolateral triangle is helpful in understanding and planning surgical approaches to the cavernous sinus and middle cranial fossa. As such, normal anatomic relationships and the sizes of the anterolateral triangle must first be recognized to better access the pathologic changes within and around this region.

KEYWORDS:

anterolateral triangle; dimensions; far lateral; lateralmost; neurosurgery

Figure 1

Superolateral view of the middle cranial fossa

The dura mater has been removed to better visualize the underlying structures. The turquoise triangle represents the anterolateral cavernous sinus surgical triangle. The anterior border is defined along the posterior border of the maxillary division of the trigeminal nerve, from the intersection with the mandibular nerve to the posterolateral-most border of the foramen rotundum; the posterior border is defined along the anterior border of the mandibular division of the trigeminal nerve, from the intersection with the mandibular nerve to the anterolateral-most border of the foramen ovale; the lateral border is defined as a line connecting the posterolateral-most border of the foramen rotundum to the anterolateral-most border of the foramen ovale.

GSPN, greater superficial petrosal nerve; Mid. Men. A., middle meningeal artery; Tri. Gang., trigeminal ganglion; V1, ophthalmic division of the trigeminal nerve; V2, maxillary division of the trigeminal nerve; V3, mandibular division of the trigeminal nerve.

Figure 2

Illustration of the anterolateral triangle viewed superiorly

This illustration highlights the borders and neighboring structures of the anterolateral triangle. The inset image is that of a skull base and can be used for orientation.