The Posterior Transpetrosal Approach in a Case of Large Retrochiasmatic Craniopharyngioma: Operative Video and Technical Nuances.

To discuss the use of the posterior petrosal approach for the resection of a retrochiasmatic craniopharyngioma.  Operative video.  In this case video, the authors discuss the surgical management of a large craniopharyngioma, presenting with mass effect on the third ventricle and optic apparatus. A first surgical stage, through an endoscopic endonasal transtubercular approach, allowed satisfactory decompression of the optic chiasma and nerves in preparation for adjuvant therapy. However, accelerated growth of the tumor, with renewed visual deficits and mass effect on the hypothalamus and third ventricle, warranted a supplementary resection. A posterior transpetrosal 1 2 (also called "retrolabyrinthine transtentorial") was performed to obtain a better exposure of the tumor and the surrounding anatomy (floor and walls of the third ventricle, perforating vessels, optic nerves, etc.) 3 . Nuances of technique and surgical pearls related to the posterior transpetrosal are discussed and illustrated in this operative video, including the posterior mobilization of the transverse-sigmoid sinuses junction, preservation of the venous anatomy during the tentorial incision, identification and preservation of the floor of the third ventricle during tumor resection, and a careful multilayer closure.  Retrochiasmatic craniopharyngiomas are difficult to reach tumors that often require skull base approaches, either endoscopic endonasal or transcranial. The posterior transpetrosal approach is an important part of the surgical armamentarium to safely resect these complex tumors. The link to the video can be found at: https://youtu.be/2MyGLJ_v1kI .