Anterior Petrosal Approach for Resection of a Petrous Apex Meningioma Causing Secondary Trigeminal Neuralgia with Concurrent Microvascular Decompression: Operative Video.

[BACKGROUND] Secondary trigeminal neuralgia (sTN) accounts for 15% of all TN cases, with tumors along the nerve course constituting a significant fraction in older adults. Medical therapy is typically ineffective or provides only transient relief, and stereotactic radiosurgery is often less effective than direct surgical decompression. While the retrosigmoid corridor is conventional, the anterior petrosal (Kawase) approach offers unique advantages for tumors involving the petrous apex and Meckel's cave. Approximately one-third of these tumors cause a concurrent neurovascular conflict. CASE DESCRIPTION: A 70-year-old woman, history of breast cancer, presented with Carbamazepine refractory sTN and suicidal ideation secondary to a petrous apex tumor with concurrent SCA compression. Main differential diagnosis was meningioma followed by metastasis. The tumor was resected via a right-sided anterior petrosal approach followed by MVD of a vascular conflict in the same setting. Histopathology was WHO grade 1 meningioma. Facial pain completely resolved. Transient abducens paresis and pseudomeningocele resolved in few weeks. The patient consented to the procedure and publication; Queen's University Ethics Board approved this report.

[INDICATION] The anterior petrosal approach provides short, direct access to pre- and suprameatal pathology while avoiding manipulation of the lower cranial nerves. ESSENTIAL STEPS: frontotemporal craniotomy, MMA coagulation and division, posterior-to-anterior dural peeling to identify GSPN, identifying medial petrous ridge, petrous apex drilling guided by studying the preoperative CT scan, dural opening and dividing the tentorium (avoiding trochlear nerve), tumor resection from the trigeminal branches and AICA, SCA dissection from the trigeminal root entry zone, and Teflon interposition to address the dual-mechanism compression.