Efficacy and outcomes of facial nerve–sparing treatment approach to cerebellopontine angle meningiomas

OBJECTIVEAdvanced microsurgical techniques contribute to reduced morbidity and improved surgical management of meningiomas arising within the cerebellopontine angle (CPA). However, the goal of surgery has evolved to preserve the quality of the patient's life, even if it means leaving residual tumor. Concurrently, Gamma Knife radiosurgery (GKRS) has become an acceptable and effective treatment modality for newly diagnosed, recurrent, or progressive meningiomas of the CPA. The authors review their institutional experience with CPA meningiomas treated with GKRS, surgery, or a combination of surgery and GKRS. They specifically focus on rates of facial nerve preservation and characterize specific anatomical features of tumor location with respect to the internal auditory canal (IAC).METHODSMedical records of 76 patients with radiographic evidence or a postoperative diagnosis of CPA meningioma, treated by a single surgeon between 1992 and 2016, were retrospectively reviewed. Patients with CPA meningiomas smaller than 2.5 cm in greatest dimension were treated with GKRS, while patients with tumors 2.5 cm or larger underwent facial nerve–sparing microsurgical resection where appropriate. Various patient, clinical, and tumor data were gathered. Anatomical features of the tumor origin as seen on preoperative imaging confirmed by intraoperative investigation were evaluated for prognostic significance. Facial nerve preservation rates were evaluated.RESULTSAccording to our treatment paradigm, 51 (67.1%) patients underwent microsurgical resection and 25 (32.9%) patients underwent GKRS. Gross-total resection (GTR) was achieved in 34 (66.7%) patients, and subtotal resection (STR) in 17 (33.3%) patients. Tumors recurred in 12 (23.5%) patients initially treated surgically, requiring additional surgery and/or GKRS. Facial nerve function was unchanged or improved in 68 (89.5%) patients. Worsening facial nerve function occurred in 8 (10.5%) patients, all of whom had undergone microsurgical resection. Upfront treatment with GKRS for CPA meningiomas smaller than 2.5 cm was associated with preservation of facial nerve function in all patients over a median follow-up of 46 months, regardless of IAC invasion and tumor origin. Anatomical origin was associated with extent of resection but did not correlate with postoperative facial nerve function. Tumor size, extent of resection, and the presence of an arachnoid plane separating the tumor and the contents of the IAC were associated with postoperative facial nerve outcomes.CONCLUSIONSCPA meningiomas remain challenging lesions to treat, given their proximity to critical neurovascular structures. GKRS is a safe and effective option for managing CPA meningiomas smaller than 2.5 cm without associated mass effect or acute neurological symptoms. Maximal safe resection with preservation of neurological function can be performed for tumors 2.5 cm or larger without significant risk of facial nerve dysfunction, and, when combined with GKRS for recurrence and/or progression, provides excellent disease control. Anatomical features of the tumor origin offer critical insights for optimizing facial nerve preservation in this cohort.

Download Full-text

Efficacy of facial nerve–sparing approach in patients with vestibular schwannomas

Journal of Neurosurgery ◽

10.3171/2011.7.jns101921 ◽

2011 ◽

Vol 115 (5) ◽

pp. 917-923 ◽

Cited By ~ 29

Author(s):

Raqeeb Haque ◽

Teresa J. Wojtasiewicz ◽

Paul R. Gigante ◽

Mark A. Attiah ◽

Brendan Huang ◽

...

Keyword(s):

Facial Nerve ◽

Residual Tumor ◽

Subtotal Resection ◽

Nerve Sparing ◽

Nerve Function ◽

Facial Nerve Function ◽

Total Resection ◽

Nerve Preservation ◽

Facial Nerve Preservation ◽

Microsurgical Resection

Object The goal of this article was to show that a combination of facial nerve–sparing microsurgical resection and Gamma Knife surgery (GKS) for expansion of any residual tumor can preserve good facial nerve function in patients with recurrent vestibular schwannoma (VS). Methods Records of individuals treated by a single surgeon with a facial nerve–sparing technique for a VS between 1998 and 2009 were retrospectively analyzed for tumor recurrence. Of the 383 patients treated for VS, 151 underwent microsurgical resection, and 20 (13.2%) of these patients required postoperative retreatment for a significant expansion of residual tumor after microsurgery. These 20 patients were re-treated with GKS. Results The rate of preservation of good facial nerve function (Grade I or II on the House-Brackmann scale) in patients treated with microsurgery for VS was 97%. Both subtotal and gross-total resection had excellent facial nerve preservation rates (97% vs 96%), although subtotal resection carried a higher risk that patients would require retreatment. In patients re-treated with GKS after microsurgery, the rate of facial nerve preservation was 95%. Conclusions In patients with tumors that cannot be managed with radiosurgery alone, a facial nerve–sparing resection followed by GKS for any significant regrowth provides excellent facial nerve preservation rates.

Download Full-text

Facial Nerve Preservation Surgery for Koos Grade 3 and 4 Vestibular Schwannomas

Neurosurgery ◽

10.1227/neu.0000000000000547 ◽

2014 ◽

Vol 75 (6) ◽

pp. 671-677 ◽

Cited By ~ 26

Author(s):

Amjad N. Anaizi ◽

Eric A. Gantwerker ◽

Myles L. Pensak ◽

Philip V. Theodosopoulos

Keyword(s):

Facial Nerve ◽

Extent Of Resection ◽

Vestibular Schwannomas ◽

Tumor Control ◽

Nerve Function ◽

Facial Nerve Function ◽

Nerve Preservation ◽

Facial Nerve Preservation ◽

Grade 3

Abstract Background: Facial nerve preservation surgery for large vestibular schwannomas is a novel strategy for maintaining normal nerve function by allowing residual tumor adherent to this nerve or root-entry zone. Objective: To report, in a retrospective study, outcomes for large Koos grade 3 and 4 vestibular schwannomas. Methods: After surgical treatment for vestibular schwannomas in 52 patients (2004–2013), outcomes included extent of resection, postoperative hearing, and facial nerve function. Extent of resection defined as gross total, near total, or subtotal were 7 (39%), 3 (17%), and 8 (44%) in 18 patients after retrosigmoid approaches, respectively, and 10 (29.5%), 9 (26.5%), and 15 (44%) for 34 patients after translabyrinthine approaches, respectively. Results: Hearing was preserved in 1 (20%) of 5 gross total, 0 of 2 near-total, and 1 (33%) of 3 subtotal resections. Good long-term facial nerve function (House-Brackmann grades of I and II) was achieved in 16 of 17 gross total (94%), 11 of 12 near-total (92%), and 21 of 23 subtotal (91%) resections. Long-term tumor control was 100% for gross total, 92% for near-total, and 83% for subtotal resections. Postoperative radiation therapy was delivered to 9 subtotal resection patients and 1 near-total resection patient. Follow-up averaged 33 months. Conclusion: Our findings support facial nerve preservation surgery in becoming the new standard for acoustic neuroma treatment. Maximizing resection and close postoperative radiographic follow-up enable early identification of tumors that will progress to radiosurgical treatment. This sequential approach can lead to combined optimal facial nerve function and effective tumor control rates.

Download Full-text

766 Endoscopic Surgery for Sporadic Vestibular Schwannoma Resection: A Systematic Review of Surgical Outcomes

British Journal of Surgery ◽

10.1093/bjs/znab134.324 ◽

2021 ◽

Vol 108 (Supplement_2) ◽

Author(s):

S Chiuta ◽

S Raza-Knight ◽

A Alalade

Keyword(s):

Facial Nerve ◽

Hearing Preservation ◽

Extent Of Resection ◽

Current Data ◽

Resection Rate ◽

Eighth Cranial Nerve ◽

Nerve Preservation ◽

Microsurgical Resection ◽

Hearing Outcomes ◽

Series Report

Abstract Introduction Vestibular schwannomas (VS) are benign intracranial tumours originating from the vestibular division of the eighth cranial nerve. The mainstay of their surgical management is microsurgery, other options are radiotherapy or radiological monitoring. Endoscopy (ES) is becoming widely used in neurosurgery and may have a role in improving visualisation and outcomes by enhancing extent of resection, facial nerve, and hearing preservation in VS resection and describe the postoperative outcomes. Method The review was conducted according to the PRISMA guidelines and yielded 31 studies for inclusion. Systematic searches of literature databases were done for studies where endoscopic-assisted and/or endoscopic resection of VS were reported. Results ES facial nerve preservation rates (median 91.3%, range 39.0 - 100%) were comparable to microsurgical treatment. Hearing outcomes were more variable in ES series and were under-reported. A median gross total resection rate of 97.4% (61.0 - 100%) was achieved in the ES series. Conclusions Current data suggest that ES-assisted resection of sporadic VS is not inferior to microsurgical resection with respect to facial nerve outcomes and extent of resection. However, some ES series report poor hearing outcomes, which are under-reported in the literature.

Download Full-text

The Offprint of an Abnormal Pre-Parotidectomy Electrodiagnostic Finding in a Normally Functioning Facial Nerve: Correlation with Intraoperative Findings, Histology and Postoperative Facial Nerve Function

Journal of Clinical Medicine ◽

10.3390/jcm11010248 ◽

2022 ◽

Vol 11 (1) ◽

pp. 248

Author(s):

Verena Katheder ◽

Matti Sievert ◽

Sarina Katrin Müller ◽

Vivian Thimsen ◽

Antoniu-Oreste Gostian ◽

...

Keyword(s):

Facial Nerve ◽

Malignant Tumor ◽

Facial Palsy ◽

Benign Lesion ◽

Nerve Function ◽

Facial Nerve Function ◽

Nerve Preservation ◽

Clinically Normal ◽

Parotid Tumors ◽

Supramaximal Stimulation

The aim of this study was to search for associations between an electrodiagnostically abnormal but clinically normal facial nerve before parotidectomy and the intraoperative findings, as well as the postoperative facial nerve function. The records of all patients treated for parotid tumors between 2002 and 2021 with a preoperative House–Brackmann score of grade I but an abnormal electrophysiologic finding were studied retrospectively. A total of 285 patients were included in this study, and 222 patients had a benign lesion (77.9%), whereas 63 cases had a malignant tumor (22.1%). Electroneurographic facial nerve involvement was associated with nerve displacement in 185 cases (64.9%) and infiltration in 17 cases (6%). In 83 cases (29.1%), no tumor–nerve interface could be detected intraoperatively. An electroneurographic signal was absent despite supramaximal stimulation in 6/17 cases with nerve infiltration and in 17/268 cases without nerve infiltration (p < 0.001). The electrophysiologic involvement of a normal facial nerve is not pathognomonic for a malignancy (22%), but it presents a rather rare (~6%) sign of a “true” nerve infiltration and could also appear in tumors without any contact with the facial nerve (~29%). Of our cases, two thirds of those with an anatomic nerve preservation and facial palsy had already directly and postoperatively recovered to a major extent in the midterm.

Download Full-text

Retrosigmoid Transmeatal Approach for Resection of Acoustic Neuroma: Operative Video and Technical Nuances of Subperineural Dissection for Facial Nerve Preservation

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0039-1688488 ◽

2019 ◽

Vol 80 (S 03) ◽

pp. S269-S270

Author(s):

James K. Liu ◽

Vincent N. Dodson ◽

Robert W. Jyung

Keyword(s):

Facial Nerve ◽

Acoustic Neuroma ◽

Protective Layer ◽

Nerve Function ◽

Facial Nerve Function ◽

Tumor Removal ◽

Nerve Preservation ◽

Tumor Capsule ◽

Acoustic Neuromas ◽

Dissection Technique

The retrosigmoid (suboccipital) approach is the workhorse for most acoustic neuromas in the cerebellopontine angle. In this operative video atlas manuscript, the authors demonstrate the nuances of the subperineural dissection technique for microsurgical resection of an acoustic neuroma via the retrosigmoid transmeatal approach. The plane is developed by separating the perineurium of the vestibular nerve away from the tumor capsule. This perineurium provides a protective layer between the tumor capsule and the facial nerve which serves as a buffer to avoid direct dissection and potential trauma to the facial nerve. Using this technique during extracapsular tumor dissection helps to maximize the extent of tumor removal while preserving facial nerve function. A gross total resection of the tumor was achieved, and the patient exhibited normal facial nerve function (Fig. 1). In summary, the retrosigmoid transmeatal approach with the use of subperineural dissection are important strategies in the armamentarium for surgical management of acoustic neuromas with the goal of maximizing tumor removal and preserving facial nerve function (Fig. 2).The link to the video can be found at: https://youtu.be/L3lPtSvJt60.

Download Full-text

Translabyrinthine Approach for Resection of Large Cystic Acoustic Neuroma: Operative Video and Technical Nuances of Subperineural Dissection for Facial Nerve Preservation

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0039-1685534 ◽

2019 ◽

Vol 80 (S 03) ◽

pp. S267-S268

Author(s):

James K. Liu ◽

Vincent N. Dodson ◽

Robert W. Jyung

Keyword(s):

Hearing Loss ◽

Facial Nerve ◽

Acoustic Neuroma ◽

Nerve Function ◽

Facial Nerve Function ◽

Nerve Preservation ◽

Translabyrinthine Approach ◽

Acoustic Neuromas ◽

Extracapsular Dissection ◽

Cerebellar Retraction

The translabyrinthine approach is advantageous for the resection of large acoustic neuromas compressing the brainstem when hearing loss is nonserviceable. This approach provides wide access through the presigmoid corridor without prolonged cerebellar retraction. Early identification of the facial nerve at the fundus is also achieved. In this operative video atlas manuscript, the authors demonstrate a step-by-step technique for microsurgical resection of a large cystic acoustic neuroma via a translabyrinthine approach. The nuances of microsurgical and skull base technique are illustrated including performing extracapsular dissection of the tumor while maintaining a subperineural plane of dissection to preserve the facial nerve. This strategy maximizes the extent of removal while preserving facial nerve function. A microscopic remnant of tumor was left adherent to the perineurium. A near-total resection of the tumor was achieved and the facial nerve stimulated briskly at low thresholds. Other than preexisting hearing loss, the patient was neurologically intact with normal facial nerve function postoperatively. In summary, the translabyrinthine approach and the use of subperineural dissection are important strategies in the armamentarium for surgical management of large acoustic neuromas while preserving facial nerve function.The link to the video can be found at: https://youtu.be/zld2cSP8fb8.

Download Full-text

Long-Term Facial Nerve Outcomes after Microsurgical Resection of Vestibular Schwannomas in Patients with Preoperative Facial Nerve Palsy

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0037-1607320 ◽

2017 ◽

Vol 79 (03) ◽

pp. 309-313 ◽

Cited By ~ 1

Author(s):

Michael Mooney ◽

Benjamin Hendricks ◽

Christina Sarris ◽

Robert Spetzler ◽

Randall Porter ◽

...

Keyword(s):

Facial Nerve ◽

Vestibular Schwannoma ◽

Nerve Palsy ◽

Facial Nerve Palsy ◽

Tumor Diameter ◽

Nerve Function ◽

Facial Nerve Function ◽

Microsurgical Resection ◽

Grade Iii

Objectives This study aimed at evaluating facial nerve outcomes in vestibular schwannoma patients presenting with preoperative facial nerve palsy. Design A retrospective review. Setting Single-institution cohort. Participants Overall, 368 consecutive patients underwent vestibular schwannoma resection. Patients with prior microsurgery or radiosurgery were excluded. Main Outcome Measures Incidence, House–Brackmann grade. Results Of 368 patients, 9 had confirmed preoperative facial nerve dysfunction not caused by prior treatment, for an estimated incidence of 2.4%. Seven of these nine patients had Koos grade 4 tumors. Mean tumor diameter was 3.0 cm (range: 2.1–4.4 cm), and seven of nine tumors were subtotally resected. All nine patients were followed up clinically for ≥ 6 months. Of the six patients with a preoperative House–Brackmann grade of II, two improved to grade I, three were stable, and one patient worsened to grade III. Of the three patients with grade III or worse, all remained stable at last follow-up. Conclusions Preoperative facial nerve palsy is rare in patients with vestibular schwannoma; it tends to occur in patients with relatively large lesions. Detailed long-term outcomes of facial nerve function after microsurgical resection for these patients have not been reported previously. We followed nine patients and found that eight (89%) of the nine patients had either stable or improved facial nerve outcomes after treatment. Management strategies varied for these patients, including rates of subtotal versus gross-total resection and the use of stereotactic radiosurgery in patients with residual tumor. These results can be used to help counsel patients preoperatively on expected outcomes of facial nerve function after treatment.

Download Full-text