Retrosigmoid Transtentorial Resection of a Petroclival Meningioma: 2-Dimensional Operative Video.

In this video, we aimed to demonstrate retrosigmoid-transtentorial resection of a 4.5 × 4 × 4.5 cm3 left-sided petroclival meningioma compressing the brainstem in a 62-yr-old male who presented with decreased hearing on the left and imbalance.  The patient was placed in park-bench position and a left-sided suboccipital craniotomy was performed. The mass was severely compressing the brainstem as well as the cranial nerves V, VI, VII, and VIII while IV was encased by the tumor. The circumferential dissection of the tumor was facilitated while the surgical corridor and exposure were enlarged by incising the tentorium. Uneventfully, the meningioma was resected in piecemeal fashion as it was not coming out easily with the ultrasonic aspirator. All relevant cranial nerves and adjacent vascular structures were protected. Early postoperative CT scan demonstrated changes due to the surgery and resolution of the compression on the brainstem. The patient made excellent recovery and he was discharged home on postoperative day 4 safely.  Petroclival meningiomas are one of the most challenging tumors for neurosurgeons due to their close proximity to the vascular structures, cranial nerves as well as the brainstem. The retrosigmoid approach provides a direct route during microsurgical resection of these tumors. By incising the tentorium, the corridor can be widened while addressing the supratentorial portion of the tumor with relative ease.