Surgical Strategy for Petroclival Meningioma-Related Trigeminal Neuralgia: The Role of Porus Trigeminus Opening.

[OBJECTIVE] Petroclival meningiomas invade Meckel's cave through the porus trigeminus, leading to secondary trigeminal neuralgia. Microsurgery and stereotactic radiosurgery (SRS) are the typical treatment options. This study investigated symptom control, outcomes, and surgical strategies for PC meningioma-induced TN.

[METHODS] We retrospectively analyzed 28 TN patients with PC meningiomas who underwent microsurgical nerve decompression between January 2021 and February 2023. In all patients undergoing a transpetrosal approach, the porus trigeminus was opened to enable the removal of the entire tumor within Meckel's cave. Clinical outcomes were assessed using the Barrow Neurologic Institute (BNI) pain intensity scale. Risk factors for poor TN outcomes and poor facial numbness were analyzed.

[RESULTS] Among 28 patients, 21 (75%) underwent the transpetrosal approach, 5 (17.9%) underwent the retrosigmoid approach, and 2 (7.1%) underwent the Dolenc approach. Following microsurgery, 23 patients (82.1%) experienced TN relief without further medication (BNI I or II). TN recurrence occurred in 2 patients (7.1%), and 3 patients (10.7%) did not achieve TN relief. Cavernous sinus invasion was significantly correlated with poor TN outcomes (P = 0.047). A history of previous SRS (P = 0.011) and upper clivus type tumor (P = 0.018) were significantly associated with poor facial numbness.

[CONCLUSIONS] Microsurgical nerve decompression is effective in improving BNI scores in patients with TN associated with PC meningiomas. Considering the results of our study, the opening of the porus trigeminus can be considered as a suggested procedure in the treatment of PC meningiomas, especially in cases accompanied by TN.