Impact of Sigmoid Sinus Anatomy on Assessing the Feasibility of the Retrofacial Access to the Entire Jugular Fossa Before Surgery

Operative Neurosurgery 28:677–686, 2025

The study evaluates the feasibility of the neuronavigated microsurgical transmastoid extended infralabyrinthine extradural retrofacial approach (mTEIER-A) in accessing the jugular fossa, emphasizing the significance of the sigmoid sinus position and horizontal angle of attack, while the sinus size has limited impact.

• The study examines the feasibility of the neuronavigated microsurgical transmastoid extended infralabyrinthine extradural retrofacial approach (mTEIER-A) for accessing the jugular fossa (JF), considering the position and size of the sigmoid sinus (SS) and the horizontal angle of attack.

• SS position medial to a reference line (P1) and horizontal angles greater than 12.5° enhance retrofacial access to the lateral aspect of the JF. The size of the SS has a limited impact.

• Precise preoperative planning is crucial to minimize the need for more invasive approaches, potentially reducing morbidity.

• The study was conducted on cadaveric specimens and highlights the importance of further clinical studies to validate findings.

• Creating an anterofacial space carries risks, including potential damage to the facial nerve (FN) and external auditory canal, which mTEIER-A aims to avoid.

• Statistical analysis confirms the significance of SS position and α-angle for retrofacial access, while SS size has a minor role.

• The study suggests that mTEIER-A is a viable approach for addressing intraosseous JFPs, emphasizing the need for careful preoperative imaging assessment.