NEUROSURGICAL FOCUS Neurosurg Focus 44 (4):E10, 2018 P etroclival meningiomas (PCMs) arise from the petroclival region with signifcant dural adherence overlying the sphenopetroclival bony interface. They are seated medial to the internal auditory meatus and posterior to the gasserian ganglion, which differenti- ates them from clival meningiomas that arise close to the midline of the clivus. 9 Large PCMs always occupy the su- prasellar, interpeduncular, prepontine, and clival regions. Despite the advances in skull base techniques designed to minimize morbidity and mortality, large PCMs still pose a great challenge to neurosurgeons. 2,9 The pretemporal trans–Meckel’s cave transtentorial approach is conceptually creating a widened gateway be- tween the middle and posterior fossae, which is performed in combination with pretemporal transcavernous 3,6 and anterior transpetrosal 5 approaches (Fig. 1). In this study, the authors describe the pretemporal trans–Meckel’s cave transtentorial approach to manage large PCMs, review the ABBREVIATIONS ACP = anterior clinoid process; CN = cranial nerve; CS = cavernous sinus; ICA = internal carotid artery; mRS = modified Rankin Scale; PCM = petro- clival meningioma. SUBMITTED December 1, 2017. ACCEPTED January 24, 2018. INCLUDE WHEN CITING DOI: 10.3171/2018.1.FOCUS17733. Pretemporal trans–Meckel’s cave transtentorial approach for large petroclival meningiomas Chih-Hsiang Liao, MD, 1 Jui-To Wang, MD, 2,4 Chun-Fu Lin, MD, 2,4 Shao-Ching Chen, MD, 2 Chung-Jung Lin, MD, 3,4 Sanford P. C. Hsu, MD, 2,4 and Min-Hsiung Chen, MD 2,4 1 Department of Neurosurgery, Neurological Institute, Taichung Veterans General Hospital, Taichung; 2 Department of Neurosurgery, Neurological Institute, and 3 Department of Radiology, Taipei Veterans General Hospital; and 4 National Yang Ming University, School of Medicine, Taipei, Taiwan OBJECTIVE Despite the advances in skull base techniques, large petroclival meningiomas (PCMs) still pose a chal- lenge to neurosurgeons. The authors’ objective of this study was to describe a pretemporal trans–Meckel’s cave trans- tentorial approach for large PCMs and to report the surgical outcomes. METHODS From 2014 to 2017, patients harboring large PCMs (> 3 cm) and undergoing their frst resection via this pro- cedure at the authors’ institute were included. In combination with pretemporal transcavernous and anterior transpetrosal approaches, the trans–Meckel’s cave transtentorial route was created. Surgical details are described and a video dem- onstrating the procedure is included. Retrospective review of the medical records and imaging studies was performed. RESULTS A total of 18 patients (6 men and 12 women) were included in this study, with mean age of 53 years. The mean sizes of the preoperative and postoperative PCMs were 4.36 cm × 4.09 cm × 4.13 cm (length × width × height) and 0.83 cm × 1.08 cm × 0.75 cm, respectively. Gross-total removal was performed in 7 patients, near-total removal (> 95%) in 7 patients, and subtotal removal in 4 patients (> 90% in 3 patients and > 85% in 1 patient). There were no surgical deaths or patients with postoperative hemiplegia. Surgical complications included transient cranial nerve (CN) III palsy (all patients, resolved in 3 months), transient CN VI palsy (2 patients), CN IV palsy (3 patients, partial recovery), hydrocephalus (3 patients), and CSF otorrhea (1 patient). Temporal lobe retraction–related neurological defcits were not observed. CONCLUSIONS A pretemporal trans–Meckel’s cave transtentorial approach offers large surgical exposure and multiple trajectories to the suprasellar, interpeduncular, prepontine, and upper-half clival regions without overt traction, which is mandatory to remove large PCMs. To unlock Meckel’s cave where a large PCM lies abutting the cave, pretemporal transcavernous and anterior transpetrosal approaches are prerequisites to create adequate exposure for the fnal trans– Meckel’s cave step. https://thejns.org/doi/abs/10.3171/2018.1.FOCUS17733 KEY WORDS anterior transpetrosal; Dolenc-Kawase approach; petroclival meningioma; pretemporal approach; skull base surgery; transcavernous; trans–Meckel’s cave transtentorial approach Neurosurg Focus Volume 44 • April 2018 1 ©AANS 2018, except where prohibited by US copyright law Unauthenticated | Downloaded 06/30/22 03:14 AM UTC