Trigeminal neuralgia caused by compression of the trigeminal nerve between the vertebral artery and Meckel's cave meningioma extending to the posterior fossa successfully treated with the endoscopic-assisted anterior petrosal approach.

BACKGROUND

Microvascular decompression (MVD) using a microscope is commonly performed for trigeminal neuralgia (TN). The advantages of endoscopic surgery for MVD are not clear. We report a case of TN caused by a Meckel's cave meningioma extending to the posterior fossa, which was successfully treated through surgical resection using a combination of a microscope and endoscope.

CASE DESCRIPTION: A 63-year-old patient complained of left facial pain. Magnetic resonance imaging showed a 30 × 30 × 25 mm mass lesion in the left petroclival region that had extended into Meckel's cave. Three-dimensional computed tomography angiography demonstrated that the trigeminal nerve passed between the tumor and the tortuous vertebral artery (VA). We selected the anterior transpetrosal approach. The trigeminal nerve was displaced due to compression by the tumor, so the entire course of the trigeminal nerve was difficult to visualize even after tumor removal. Consequently, we switched from the microscope to an endoscope and observed the root entry zone (REZ) of the trigeminal nerve. We confirmed that the VA compressed the REZ of the trigeminal nerve and inserted small Teflon pieces to relieve the compression. TN disappeared, and he was discharged home with no complications.

CONCLUSION

Surgical resection of tumors near the trigeminal nerve causing TN must carefully examine the trigeminal nerve from the REZ to Meckel's cave to identify any coexistent vascular compression, which may be difficult using only a microscope due to significant displacement of the trigeminal nerve. In such cases, the use of an endoscope is effective to inspect the entire trigeminal nerve directly.