Anatomical variations of the ten triangles around the cavernous sinus

Abstract

The dimensions of the 10 triangles around the cavernous sinus were measured to define the anatomical characteristics of the triangles and to compare their consistency in shape and area. Twelve tissue blocks containing the bilateral cavernous sinuses and medial two-thirds of the middle cranial fossae were obtained from Japanese adults at autopsy, fixed to a stereotactic frame, and examined with an operative microscope. The dimensions of each triangle were measured with calipers and compared, based on the same point and border. The anteromedial triangle and the superolateral (Parkinson's) triangle were more consistent in shape than the paramedial and oculomotor triangles, but the oculomotor triangle was larger in area than these other triangles. The posteromedial (Kawase's) triangle was more consistent in shape and larger than the anterolateral, lateral, and the posterolateral (Glasscock's) triangles. The anteromedial and superolateral (Parkinson's) triangles are important for the combined epi- and subdural approach to cavernous sinus lesions. The posteromedial (Kawase's) triangle is important for gaining access to the posterior cranial fossa from the middle cranial fossa.

Endoscopic endonasal study of the cavernous sinus and quadrangular space: Anatomic relationships

“…In this study, the anteromedial triangle presented an average surface area of 36.07 mm 2 (±4.15 mm 2 ), a similar finding to the results presented by Isolan et al of 36.26 mm 2 (±3.75 mm 2 ) but slightly different than those by Watanabe et al of 41.2 mm 2 (±15.4 mm 2 ). Nonetheless, both studies measured the anteromedial triangle's area manually through a transcranial approach …”

“…However, to the authors' knowledge, this is the first study to measure the surface area of the anteromedial, anterolateral, and Parkinson's triangle as visualized via a ventral perspective, as well as to measure the surface area of the quadrangular space. These triangles have been the subject of variable nomenclature; however, in this study, we adopted the system described by Rhoton …”

The petrosal nerves: Anatomy, pathology, and surgical considerations

“…Drilling through the floor of Glass-cock's triangle (where the LPN is found) exposes the infratemporal fossa (Watanabe et al, 2003). The petrous carotid artery can be found in the anterior portion of Kawase's triangle, the cochlea is located beneath the lateral part of this triangle, and drilling posterior to the petrous carotid and medial to the cochlea in Kawase's triangle will expose the clivus (Rhoton, 2002).…”

The relationship between the superior petrosal sinus and the porus trigeminus: an anatomical study

“…The inferolateral triangle was defined as lines connecting the dural entry point of the trochlear nerve, the dural entry point of the abducent nerve, and the entry point of the petrosal vein into the SPS. 11,13,23,24,33 The SPS also forms the superior boundary of the Trautmann triangle, which is used for posterior petrosectomy approaches, and the medial border of the Kawase triangle (rhomboid; posteromedial triangle), which is used for anterior petrosectomy. 11,13,23,24,30 Approaches around the Meckel cave have been based on petrosal vein drainage types.…”