Durability of hearing preservation after microsurgical treatment of vestibular schwannoma using the middle cranial fossa approach

Clinical article

Restricted access


The middle cranial fossa (MCF) approach is a microsurgical technique described as a primary option in the treatment of small, intracanalicular schwannomas involving the eighth cranial nerve. Excellent rates of complete tumor resection, hearing preservation, preservation of facial nerve function, and low complication rates have been reproduced using this technique. However, the durability of hearing preservation attained using the various treatment options has not been adequately assessed. The purpose of this study was to evaluate the durability of long-term hearing preservation in patients with vestibular schwannoma (VS) treated via the MCF approach. The authors hypothesize that hearing preservation in these patients will prove to be durable years after treatment in a high percentage of cases.


Retrospective medical chart review was performed in 103 consecutive patients undergoing resection of VS via a modified MCF approach between 1999 and 2008. Patients in whom surgical goals were gross-total resection and hearing preservation were included. Preoperative and postoperative hearing assessment was performed using standard audiometric testing, and classified according to American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) guidelines as a primary outcome measure. Outcomes and neurological complications initially, and at 1, 3, and 5 years following operation were analyzed.


Initial hearing preservation rates were in keeping with the best previously published results. At initial postoperative audiometric follow-up, of the patients presenting with Class A hearing, 67% remained Class A, 17% were Class B, 1% were Class C, and 15% were Class D. Of patients presenting with Class B hearing, 24% were Class A, 53% remained Class B, 6% were Class C, and 18% were Class D. Of patients presenting with Class C hearing, 100% remained Class C.

To assess the durability of hearing preservation in our patients, the authors evaluated hearing function at regular intervals after the initial postoperative audiometric follow-up. Audiometric data were available for 56 patients at 5-year follow-up. Of the 20 patients with Class A hearing at initial postoperative follow-up with 5-year follow-up, 13 (65%) remained Class A, 6 (30%) were Class B, and 1 (5%) was Class C. Of the 12 patients with Class B hearing at initial postoperative follow-up with 5-year follow-up, 4 (33%) were Class A, 4 (33%) remained Class B, and 4 (33%) were Class C. Of the 3 patients with Class C hearing at initial postoperative follow-up with 5-year follow-up, all 3 (100%) remained Class C.


A majority of patients with preserved hearing following the MCF approach for treatment of VS experience durability of their preserved hearing at 5-year follow-up. The initial AAO-HNS classification was preserved in 13 (65%) of the 20 patients who had Class A hearing at 5 years, and in 8 (67%) of the 12 who had Class B hearing at 5 years. Overall, a decline in AAO-HNS classification was noted in 15% of patients with preserved Class A hearing, and in 33% of those with preserved Class B hearing. Facial nerve function was preserved in 91% of cases. Superior hearing preservation as well as good outcomes in facial nerve function and few serious complications can be accomplished using the MCF approach for resection of small VSs.

Abbreviations used in this paper:AAO-HNS = American Academy of Otolaryngology–Head and Neck Surgery; ABR = auditory brainstem response; CPA = cerebellopontine angle; HB = House-Brackmann; IAC = internal auditory canal; MCF = middle cranial fossa; PTA = pure-tone average; RST = retrosigmoid-transmeatal; SRS = stereotactic radiosurgery; VS = vestibular schwannoma; WRS = word recognition score.

Article Information

Address correspondence to: B. Gregory Thompson, M.D., Department of Neurosurgery, University of Michigan, 1500 East Medical Center Drive, Room 3552 Taubman Center, Ann Arbor, Michigan 48109-5338. email: gregthom@umich.edu.

Please include this information when citing this paper: published online February 15, 2013; DOI: 10.3171/2013.1.JNS1297.

© AANS, except where prohibited by US copyright law.



  • View in gallery

    The AAO-HNS criteria grade hearing function based on PTA and WRS. Scatterplots depict audiometry results at (upper left) preoperative, (upper right) 1-year initial postoperative, and (lower) 5-year postoperative assessments. HL = hearing level.

  • View in gallery

    Kaplan-Meier survival curve depicting percentage of patients maintaining WRS > 70% over time. Some debate exists as to whether the utility of hearing preservation should be measured purely by speech discrimination. For this analysis, WRS ≤ 70% at most recent audiometric assessment was considered to represent loss of hearing.



Arriaga MAChen DAFukushima T: Individualizing hearing preservation in acoustic neuroma surgery. Laryngoscope 107:104310471997


Arts HATelian SAEl-Kashlan HThompson BG: Hearing preservation and facial nerve outcomes in vestibular schwannoma surgery: results using the middle cranial fossa approach. Otol Neurotol 27:2342412006


Betchen SAWalsh JPost KD: Long-term hearing preservation after surgery for vestibular schwannoma. J Neurosurg 102:692005


Chee GHNedzelski JMRowed D: Acoustic neuroma surgery: the results of long-term hearing preservation. Otol Neurotol 24:6726762003


Chopra RKondziolka DNiranjan ALunsford LDFlickinger JC: Long-term follow-up of acoustic schwannoma radiosurgery with marginal tumor doses of 12 to 13 Gy. Int J Radiat Oncol Biol Phys 68:8458512007


Colletti VFiorino F: Is the middle fossa approach the treatment of choice for intracanalicular vestibular schwannoma?. Otolaryngol Head Neck Surg 132:4594662005


Combs SEThilmann CDebus JSchulz-Ertner D: Long-term outcome of stereotactic radiosurgery (SRS) in patients with acoustic neuromas. Int J Radiat Oncol Biol Phys 64:134113472006


Committee on Hearing and Equilibrium: Committee on Hearing and Equilibrium guidelines for the evaluation of hearing preservation in acoustic neuroma (vestibular schwannoma). Otolaryngol Head Neck Surg 113:1791801995


Flickinger JCKondziolka DNiranjan AMaitz AVoynov GLunsford LD: Acoustic neuroma radiosurgery with marginal tumor doses of 12 to 13 Gy. Int J Radiat Oncol Biol Phys 60:2252302004


Friedman RAKesser BBrackmann DEFisher LMSlattery WHHitselberger WE: Long-term hearing preservation after middle fossa removal of vestibular schwannoma. Otolaryngol Head Neck Surg 129:6606652003


Fukuoka STakanashi MHojyo AKonishi MTanaka CNakamura H: Gamma knife radiosurgery for vestibular schwannomas. Prog Neurol Surg 22:45622009


Gjurić MWigand MEWolf SR: Enlarged middle fossa vestibular schwannoma surgery: experience with 735 cases. Otol Neurotol 22:2232312001


Goel ASekhar LNLangheinrich WKamerer DHirsch B: Late course of preserved hearing and tinnitus after acoustic neurilemoma surgery. J Neurosurg 77:6856891992


Hasegawa TKida YKobayashi TYoshimoto MMori YYoshida J: Long-term outcomes in patients with vestibular schwannomas treated using gamma knife surgery: 10-year follow up. J Neurosurg 102:10162005


Hecht CSHonrubia VFWiet RJSims HS: Hearing preservation after acoustic neuroma resection with tumor size used as a clinical prognosticator. Laryngoscope 107:112211261997


Holsinger FCCoker NJJenkins HA: Hearing preservation in conservation surgery for vestibular schwannoma. Am J Otol 21:6957002000


House JWBrackmann DE: Facial nerve grading system. Otolaryngol Head Neck Surg 93:1461471985


House WF: Surgical exposure of the internal auditory canal and its contents through the middle, cranial fossa. Laryngoscope 71:136313851961


Iwai YYamanaka KKubo TAiba T: Gamma knife radiosurgery for intracanalicular acoustic neuromas. J Clin Neurosci 15:9939972008


Iwai YYamanaka KShiotani MUyama T: Radiosurgery for acoustic neuromas: results of low-dose treatment. Neurosurgery 53:2822882003


Jacob ARobinson LL JrBortman JSYu LDodson EEWelling DB: Nerve of origin, tumor size, hearing preservation, and facial nerve outcomes in 359 vestibular schwannoma resections at a tertiary care academic center. Laryngoscope 117:208720922007


Jaisinghani VJLevine SCNussbaum EHaines SLindgren B: Hearing preservation after acoustic neuroma surgery. Skull Base Surg 10:1411472000


Kondziolka DLunsford LDMcLaughlin MRFlickinger JC: Long-term outcomes after radiosurgery for acoustic neuromas. N Engl J Med 339:142614331998


Kumon YSakaki SKohno KOhta SNakagawa KOhue S: Selection of surgical approaches for small acoustic neurinomas. Surg Neurol 53:52602000


Lundborg GDahlin LB: The pathophysiology of nerve compression. Hand Clin 8:2152271992


Lunsford LDNiranjan AFlickinger JCKondziolka D: Navigating change and the acoustic neuroma story: methods, outcomes, and myths. Clin Neurosurg 55:47612008


Matsunaga TKanzaki JHosoda Y: Angiogenesis from the eighth cranial nerve to vestibular schwannomas. Acta Otolaryngol 116:52581996


Matsunaga TKanzaki JHosoda Y: The vasculature of the peripheral portion of the human eighth cranial nerve. Hear Res 101:1191311996


Meyer TACanty PAWilkinson EPHansen MRRubinstein JTGantz BJ: Small acoustic neuromas: surgical outcomes versus observation or radiation. Otol Neurotol 27:3803922006


Mohr GSade BDufour JJRappaport JM: Preservation of hearing in patients undergoing microsurgery for vestibular schwannoma: degree of meatal filling. J Neurosurg 102:152005


Myrseth EMøller PPedersen PHVassbotn FSWentzel-Larsen TLund-Johansen M: Vestibular schwannomas: clinical results and quality of life after microsurgery or gamma knife radiosurgery. Neurosurgery 56:9279352005


Niranjan ALunsford LDFlickinger JCMaitz AKondziolka D: Dose reduction improves hearing preservation rates after intracanalicular acoustic tumor radiosurgery. Neurosurgery 45:7537651999


Niranjan AMathieu DFlickinger JCKondziolka DLunsford LD: Hearing preservation after intracanalicular vestibular schwannoma radiosurgery. Neurosurgery 63:105410632008


Noudel RGomis PDuntze JMarnet DBazin ARoche PH: Hearing preservation and facial nerve function after microsurgery for intracanalicular vestibular schwannomas: comparison of middle fossa and retrosigmoid approaches. Acta Neurochir (Wien) 151:9359452009


Paek SHChung HTJeong SSPark CKKim CYKim JE: Hearing preservation after gamma knife stereotactic radiosurgery of vestibular schwannoma. Cancer 104:5805902005


Palva TTroupp HJauhiainen T: Hearing preservation in acoustic neurinoma surgery. Acta Otolaryngol 99:171985


Pennings RJMorris DPClarke LAllen SWalling SBance ML: Natural history of hearing deterioration in intracanalicular vestibular schwannoma. Neurosurgery 68:68772011


Prasher DKTun TBrookes GBLuxon LM: Mechanisms of hearing loss in acoustic neuroma: an otoacoustic emission study. Acta Otolaryngol 115:3753811995


Régis JCarron RPark MCSoumare ODelsanti CThomassin JM: Wait-and-see strategy compared with proactive Gamma Knife surgery in patients with intracanalicular vestibular schwannomas. J Neurosurg 113:Suppl1051112010


Rowe JGRadatz MWWalton LHampshire ASeaman SKemeny AA: Gamma knife stereotactic radiosurgery for unilateral acoustic neuromas. J Neurol Neurosurg Psychiatry 74:153615422003


Sanna MKhrais TRusso APiccirillo EAugurio A: Hearing preservation surgery in vestibular schwannoma: the hidden truth. Ann Otol Rhinol Laryngol 113:1561632004


Sanna MZini CMazzoni AGandolfi APareschi RPasanisi E: Hearing preservation in acoustic neuroma surgery. Middle fossa versus suboccipital approach. Am J Otol 8:5005061987


Shelton CHitselberger WEHouse WFBrackmann DE: Hearing preservation after acoustic tumor removal: long-term results. Laryngoscope 100:1151191990


Shiobara ROhira TInoue YKanzaki JKawase T: Extended middle cranial fossa approach for vestibular schwannoma: technical note and surgical results of 896 operations. Prog Neurol Surg 21:65722008


Sladky JTTschoepe RLGreenberg JHBrown MJ: Peripheral neuropathy after chronic endoneurial ischemia. Ann Neurol 29:2722781991


Slattery WH IIIBrackmann DEHitselberger W: Middle fossa approach for hearing preservation with acoustic neuromas. Am J Otol 18:5966011997


Spiegelmann RLidar ZGofman JAlezra DHadani MPfeffer R: Linear accelerator radiosurgery for vestibular schwannoma. J Neurosurg 94:7132001


Stangerup SECaye-Thomasen PTos MThomsen J: The natural history of vestibular schwannoma. Otol Neurotol 27:5475522006


Sughrue MEYang IAranda DLobo KPitts LHCheung SW: The natural history of untreated sporadic vestibular schwannomas: a comprehensive review of hearing outcomes. Clinical article. J Neurosurg 112:1631672010


Tos MStangerup SECayé-Thomasen PTos TThomsen J: What is the real incidence of vestibular schwannoma?. Arch Otolaryngol Head Neck Surg 130:2162202004


Tos MThomsen J: Epidemiology of acoustic neuromas. J Laryngol Otol 98:6856921984


Tucci DLTelian SAKileny PRHoff JTKemink JL: Stability of hearing preservation following acoustic neuroma surgery. Am J Otol 15:1831881994


Ylikoski JPalva TCollan Y: Eighth nerve in acoustic neuromas. Special reference to superior vestibular nerve function and histopathology. Arch Otolaryngol 104:5325371978


Cited By



All Time Past Year Past 30 Days
Abstract Views 9 9 9
Full Text Views 90 90 26
PDF Downloads 100 100 36
EPUB Downloads 0 0 0


Google Scholar