Microscopic and endoscopic extracranial approaches to the cavernous sinus: anatomic study

Area of Science:

• Neurosurgery
• Anatomy
• Surgical Techniques

Background:

• Extracranial approaches to the cavernous sinus (CS) have evolved over two decades using microscopic and endoscopic methods.
• Understanding the anatomical nuances of these approaches is crucial for effective surgical planning.

Purpose of the Study:

• To describe the distinct anatomical features of various extracranial cavernous sinus approaches.
• To compare the efficacy of these approaches in exposing the sella and parasellar regions.

Main Methods:

• Ten adult cadaver heads with injected arterial systems were utilized.
• Five distinct approaches were performed: endonasal microscopic transsphenoidal, sublabial microscopic transsphenoidal (including a variation), transmaxillary microscopic, paraseptal endoscopic transsphenoidal, and transethmoid-pterygoid-sphenoidal endoscopic.
• Cavernous sinus exposure was graded based on visualization and surgical maneuverability.

Main Results:

• Transsphenoidal approaches (microscopic and endoscopic) provided good medial CS exposure; the transmaxillary approach was insufficient.
• The sublabial microscopic approach variation offered the widest exposure.
• The transmaxillary microscopic and endoscopic approaches visualized the lateral CS compartment well, with posterior ethmoid and medial pterygoid processes being limiting structures.

Conclusions:

• The sublabial transsphenoidal microscopic approach, with variations, provides the most versatile extracranial microscopic exposure of the sella and CS.
• The paraseptal binostril endoscopic approach offers excellent CS exposure.
• The transethmoid-pterygoid-sphenoidal endoscopic approach demonstrates the best maneuverability within the lateral CS compartment.