Surgical Treatment and Clinical Outcomes of Petroclival Meningiomas: A Single-Center Experience of 107 Patients

ObjectiveThis study aimed to establish optimal surgical strategies via reviewing the clinical outcomes of various surgical approaches for the pertroclival meningiomas (PCMs).MethodsThis retrospective study enrolled 107 patients with PCMs at the authors’ institution from year 2010 to 2020. Patient demographics, the clinical characteristics, various operative approaches, major morbidity, post-operative cranial nerve deficits and tumor progression or recurrence were analyzed.ResultsThe subtemporal transtentorial approach (STA), the Kawase approach (KA), the retrosigmoid approach (RSA) and the anterior sigmoid approach (ASA), namely the posterior petrosal approach (PPA) were adopted for 17 cases, 22 cases, 31 cases and 34 cases respectively. Total or subtotal resection was achieved in 96 cases (89.7%). The incidence of new-onset and aggravated cranial nerve dysfunction were 13.1% (14/107) and 10.4% (15/144), respectively. Furthermore, 14 cases suffered from intracranial infection, 9 cases had cerebrospinal fluid leakage, and 3 cases sustained intracranial hematoma (1 case underwent second operation). The mean preoperative and postoperative Karnofsky Performance Status (KPS) score was 80 (range 60-100) and 78.6 (range 0-100), but this was not statistically significant (P>0.05). After a mean follow-up of 5.1 years (range 0.3- 10.6 years), tumor progression or recurrence was confirmed in 23 cases. Two cases died from postoperative complications.ConclusionsFor the treatment of PCMs, it is still a challenge to achieve total resection. With elaborate surgical plans and advanced microsurgical skills, most patients with PCMs can be rendered tumor resection with satisfactory extent and functional preservation, despite transient neurological deterioration during early postoperative periods.

Modified Transpetrosal–Transtentorial Approach for Resection of Large and Giant Petroclival Meningioma: Technical Nuance and Surgical Experiences

Background Meningiomas arising from the petroclival area remain a challenge for neurosurgeons. Various approaches have been proposed to achieve maximum resection with minimal morbidity and mortality. Also, some articles correlated preservation of adjacent veins with less neurologic deficits. Objective To describe the experiences in using a new technique to achieve maximal resection of petroclival meningiomas and preserving the superior petrosal veins (SPVs) and the superior petrosal sinus (SPS). Methods A retrospective analysis of 26 patients harboring a true petroclival meningioma with a diameter ≥25 mm and undergoing surgery with the modified transpetrosal–transtentorial approach (MTTA) was performed. Results Fifty-four percent of 22 patients complained of severe headache at presentation. There was also complaint of cranial nerve (CN) deficit, with CN VII deficit being the most common (present in 42% of patients). The average tumor size (measured as maximum diameter) was 45.2 mm, and most of the tumors compressed the brainstem. Total resection was achieved in 12 patients (46.2%), whereas the others were excised subtotally (54.8%). Most of the patients had WHO grade I (96.1%) meningioma; only one had a grade II (3.8%) meningioma. In addition, clinical improvement and persistence of symptoms were observed in 17 (65.4%) and 8 (30.7%) patients, respectively, and postoperative permanent CN injury was observed in 3 (11.5%) patients. Conclusion Using the MTTA, maximal resection with preservation of the CNs and neurovascular SPV-SPS complex can be achieved. Therefore, further studies and improvements of the technique are required to increase the total resection rate without neglecting the complications that may develop postoperatively.

Combined Microscopic-Endoscopic Transmastoid Resection of a Petrous Meningioma: 2-Dimensional Operative Video

Petrous meningiomas are defined as tumors with a basal dural attachment on the posterior surface of the petrous bone.1 Their insertion can be anterior to the meatus (petrous apex meningiomas), or posterior to the meatus, with associated hyperostotic bony invasion either pre- or retro-meatal.2 These meningiomas are amenable to curative surgical removal and have better surgical outcomes than more medially located true petroclival meningiomas that originate medial to the fifth nerve.2-4 They, however, remain challenging because of their close relationship to critical neurovascular structures in the cerebellopontine angle.5 The posterior petrous meningiomas might reach a significant size with compression of the cerebellum, the brainstem, and involvement of the cranial nerves, and extend posteriorly to the transverse sigmoid sinus.2,6 Transmastoid approach with skeletonization and lateral reflection of the transverse sigmoid sinus provides a superb exposure without cerebellar retraction.6,7 The ease and complete resection of the tumor and invaded bone can be facilitated by combined microscopic-endoscopic techniques. We demonstrate these principles through the resection of a petrosal meningioma in a 56-yr-patient who presented with headaches, nystagmus, and mild cerebellar signs. The patient consented to the procedure. Image at 1:36 reprinted with permission from Al-Mefty O, Operative Atlas of Meningiomas. Vol 1, ©LWW, 1998.

Study of comparative surgical exposure to the petroclival region using patient-specific, petroclival meningioma virtual reality models

OBJECTIVE Despite advancement of surgical techniques, the attachments of petroclival meningiomas near the central clival depression (CCD) remain difficult to visualize. With existing methods, the amount of tumor near the CCD that is inaccessible through various approaches cannot be compared. Tumors distort the brainstem, changing the size of the operative corridor for some but not all approaches; therefore, using cadavers with normal posterior fossae makes it impossible to compare different approaches to the tumor. The authors used virtual reality (VR) models created from the imaging data of patients to compare various surgical approaches that have otherwise been incomparable in previous studies. METHODS CT and MRI data obtained in 15 patients with petroclival meningiomas were used to create anatomically accurate 3D VR models. For each model, various surgical approaches were performed, and the surgical freedom to 6 targets of the regions were measured. Furthermore, portions of the tumor that were visually blocked by the brainstem or bony structures were segmented and recorded as blinded volumes for comparison. RESULTS The extended retrosigmoid approach generated excellent exposure of the petroclival region, but for most specimens, there was inaccessible tumor volume adjacent to the brainstem (mean 641.3 mm3, SE 161.8). In contrast, the brainstem sides of the tumors were well-visualized by all the transpetrosal approaches. The blinded volume of the tumor was largest for the retrolabyrinthine approach, and this was statistically significant compared with all other approaches (mean 2381.3 mm3, SE 185.4). CONCLUSIONS The authors performed a novel laboratory study by using patient CT and MRI data to generate 3D virtual models to compare surgical approaches. Since it is impossible to perform various approaches in separate surgeries in patients for comparison, VR represents a viable alternative for such comparative investigations.

Petroclival Meningiomas: A Simple System That Could Help in Selecting the Approach

BACKGROUND Petroclival meningiomas (PCM) represent a neurosurgical challenge due to their strategic location close to the brainstem. OBJECTIVE To assess the applicability of a retrosigmoid approach (RSA) by analyzing the degree of displacement of the middle cerebellar peduncle (MCP) elicited by PCM. METHODS Patients with PCM were prospectively included and divided into those whose imaging studies showed that the posterior end of the MCP was displaced by the tumor and were eligible for and underwent RSA (group A) and those who were not eligible for RSA and who underwent surgery via a posterior transpetrosal approach (group B). We compared tumor behavior, clinical characteristic of patients and surgical results. RESULTS Twenty patients with PCM were enrolled and allocated to group A (n = 15) or group B (n = 5). The clinical manifestations were more severe in group B; tumors in this group were larger and gross total removal was achieved in only 1 patient (20%). In comparison, in 12 cases on group A, tumors could be totally removed (80%) and all of these patients could recover their quality of life after surgery. CONCLUSION To our knowledge, this study is the first to consider displacement of the MCP when establishing a suitable surgical approach for PCM. Our results suggest that the RSA becomes increasingly suitable when peduncle displacement is greater. By using this method, it was also possible to identify two types of tumors: petroclivals (group A) and clivopetrosals (group B), that show some specific clinical and surgical differences.

Posterior petrosal approach for microsurgical resection of petroclival meningioma: 3-Dimensional operative video

Background: Petroclival meningiomas are challenging lesions considering their deep location and close relationship with many vital neurovascular structures.[1-8] Case Description: We present the case of a 54-year-old male presenting a history of headache, dizziness, and tinnitus on the left side, associated with left facial hypoesthesia. Preoperative imaging depicted a lesion highly suggestive of a petroclival meningioma with important compression of the brainstem. Considering worsening of symptoms, size, and location of this lesion, microsurgical resection was indicated. A left posterior petrosal approach was employed with aid of neurophysiological monitoring. The patient was placed in a true lateral position and an arciform incision was done. First, the mastoidectomy was performed and then the craniotomy around encompassing both posterior and middle cranial fossae. Middle and posterior fossa dural incisions were connected through coagulation of the superior petrosal sinus. Then tentorium was all the way cut to the incisura. After that, sigmoid sinus can be mobilized posteriorly, increasing exposure of presigmoid space. The area since jugular foramen up to the supratentorial region was fully exposed, allowing safe total resection of the lesion. Postoperative imaging demonstrated complete tumor removal. Patient presented improvement of symptoms, with no new neurological deficits on follow-up. Conclusion: The posterior petrosal approach provided a shorter pathway and direct angle of attack to the tumor attachment, allowing successful resection.[1,6] Extensive laboratory training is essential to get familiarized with the complex anatomical relationships in that area. Informed consent was obtained from the patient for the procedure and publication of this operative video.

Presigmoid transpetrous approach (partial petrosectomy) combined with subtemporal transtentorial approach for petroclival meningioma

Introduction: Petroclival meningiomas constitute 3 to 10% of meningiomas of the posterior fossa, they originate in the petroclival fissure, in the upper part of the clivus, petrosal apex, and medial to the trigeminal nerve. Resection of these tumors is a neurosurgical challenge. The combined partial petrosectomy approach associated with a sub-temporal approach is a technique described by various authors; however, its performance is considered highly complex. We report the case of a petroclival meningioma operated successfully in our hospital using a combined presigmoid and subtemporal transtentorial transpetrosal approach. Clinical case: 33-year-old female patient with a clinical picture of headache, nausea, and gait disturbance. Brain magnetic resonance imaging showed a large right petroclival tumor (4.2x3.9x3.8cm) that displaced the brainstem and secondary hydrocephalus. The hydrocephalus was treated with a ventricular peritoneal shunt. Then, the tumor was resected using a combined presigmoid and subtemporal transpetrosal approach, a technique that allowed adequate exposure of the tumor, achieving complete resection, without intraoperative complications. Postoperative evolution was favorable, with no sequelae. Conclusion: The combined presigmoid and transtentorial subtemporal transpetrous approach for petroclival meningiomas is an effective and feasible technique to perform in our environment. The support of technology such as Neuronavigation, the ultrasonic aspirator, intraoperative monitoring, and adequate experience in skull base surgery are fundamental factors for the success of this surgery. Keywords: Meningioma, Skull Base Neoplasms, Craniotomy, Neurosurgical Procedures. (Source: MeSH NLM)