Extended transcavernous posterior clinoidectomy in endoscopic endonasal surgery

Area of Science:

• Neurosurgery
• Skull Base Surgery
• Endoscopic Endonasal Surgery

Background:

• Mastery of posterior clinoidectomy is crucial for endoscopic endonasal approaches, particularly for resecting chondroid tumors involving the posterior clinoid process (PCP).
• Existing techniques include intradural, extradural, and transcavernous interdural approaches.

Purpose of the Study:

• To introduce and evaluate a novel extended transcavernous posterior clinoidectomy technique.
• To compare the efficacy of this new technique with established methods for PCP exposure.

Main Methods:

• Analysis of CT angiography and 3D reconstructions of the PCP in 50 adults.
• Performance of extradural, transcavernous, and extended transcavernous posterior clinoidectomies in 20 human cadaveric heads.
• Sequential comparison of anatomical landmarks and exposed areas for each technique.

Main Results:

• PCPs were categorized as normal (≤8 mm) or complex (>8 mm).
• The extended transcavernous approach maximally exposed PCP height (9.6 ± 0.4 mm) compared to extradural (4.7 ± 0.5 mm) and transcavernous (7.3 ± 0.8 mm) techniques (p < 0.0001).

Conclusions:

• The extended transcavernous posterior clinoidectomy is a novel variant for maximal PCP exposure in endoscopic endonasal surgery.
• Preoperative skull base imaging is essential for effective surgical planning.