{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:01:53Z","timestamp":1787025713745,"version":"build-2736575974"},"reference-count":70,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["FOC"],"published-print":{"date-parts":[[2009,10]]},"abstract":"\n Object<\/jats:title>\n Intraoperative neurophysiological monitoring has become an integral part of vestibular schwannoma surgery. The aim of this article was to review the different techniques of intraoperative neurophysiological monitoring in vestibular schwannoma surgery, identify the clinical impact of certain pathognomonic patterns on postoperative outcomes of facial nerve function and hearing preservation, and highlight the role of postoperative medications in improving delayed cranial nerve dysfunction in the different reported series.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n The authors performed a review of the literature regarding intraoperative monitoring in acoustic\/vestibular schwannoma surgery. The different clinical series representing different monitoring techniques were reviewed. All the data from clinical series were analyzed in a comprehensive and comparative model.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n Intraoperative brainstem auditory evoked potential monitoring, direct cochlear nerve action potential monitoring, and facial nerve electromyography are the main tools used to assess the functional integrity of an anatomically intact cranial nerve. The identification of pathognomonic brainstem auditory evoked potential and electromyography patterns has been correlated with postoperative functional outcome. Recently, perioperative administration of intravenous hydroxyethyl starch and nimodipine as vasoactive and neuroprotective agents was shown to improve vestibular schwannoma functional outcome in few reported studies.<\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n Recent advances in electrophysiological technology have considerably contributed to improvement in functional outcome of vestibular neuroma surgery in terms of hearing preservation and facial nerve paresis. Perioperative intravenous nimodipine and hydroxyethyl starch may be valuable additions to surgery.<\/jats:p>\n <\/jats:sec>","DOI":"10.3171\/2009.8.focus09144","type":"journal-article","created":{"date-parts":[[2009,10,1]],"date-time":"2009-10-01T12:05:19Z","timestamp":1254398719000},"page":"E9","source":"Crossref","is-referenced-by-count":65,"title":["Intraoperative neurophysiological monitoring in vestibular schwannoma surgery: advances and clinical implications"],"prefix":"10.3171","volume":"27","author":[{"given":"A. Samy","family":"Youssef","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, University of South Florida, Tampa, Florida; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela E.","family":"Downes","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Mississippi, Jackson, Mississippi"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"key":"b1-0270009","series-title":"J Neurosci","first-page":"1041","article-title":"Nimodipine accelerates axonal sprouting after surgical repair of rat facial nerve","volume":"16","author":"Angelov","year":"1996"},{"key":"b2-0270009","series-title":"Laryngoscope","first-page":"1911","article-title":"Assessment of real-time clinical facial function during vestibular schwannoma resection","volume":"110","author":"Axon","year":"2000"},{"key":"b3-0270009","series-title":"Science","first-page":"382","article-title":"Far-field acoustic response: origins in the cat","volume":"189","author":"Buchwald","year":"1975"},{"key":"b4-0270009","series-title":"Skull Base Surg","first-page":"1","article-title":"Changes in directly recorded cochlear nerve compound action potentials during acoustic tumor surgery","volume":"4","author":"Colletti","year":"1994"},{"key":"b5-0270009","series-title":"Skull Base Surg","first-page":"187","article-title":"Intraoperative monitoring for hearing preservation and restoration in acoustic neuroma surgery","volume":"10","author":"Colletti","year":"2000"},{"key":"b6-0270009","series-title":"Otol Neurotol","first-page":"826","article-title":"A comparison of direct eighth nerve monitoring and auditory brainstem response in hearing preservation surgery for vestibular schwannoma","volume":"25","author":"Danner","year":"2004"},{"key":"b7-0270009","series-title":"Otol Neurotol","first-page":"388","article-title":"Predictive factors of long-term facial nerve function after vestibular schwannoma surgery","volume":"23","author":"Fenton","year":"2002"},{"key":"b8-0270009","series-title":"Neurosurgery","first-page":"1140","article-title":"Quantitative parameters of intraoperative electromyography predict facial nerve outcomes for vestibular schwannoma surgery","volume":"46","author":"Goldbrunner","year":"2000"},{"key":"b9-0270009","series-title":"J Neurocytol","first-page":"241","article-title":"Nimodipine maintains in vivo the increase in GFAP and enhances the astroglial ensheathment of surviving motoneurons in the rat following permanent target deprivation","volume":"26","author":"Guntinas-Lichius","year":"1997"},{"key":"b10-0270009","series-title":"Mayo Clin Proc","first-page":"92","article-title":"Improved preservation of facial nerve function with use of electrical monitoring during removal of acoustic neuromas","volume":"62","author":"Harner","year":"1987"},{"key":"b11-0270009","series-title":"Neurology","first-page":"1551","article-title":"Effect of BAEP monitoring on hearing preservation during acoustic neuroma resection","volume":"42","author":"Harper","year":"1992"},{"key":"b12-0270009","series-title":"Otolaryngol Head Neck Surg","first-page":"146","article-title":"Facial nerve grading system","volume":"93","author":"House","year":"1985"},{"key":"b13-0270009","series-title":"Am J Otol","first-page":"249","article-title":"Acoustic neuroma surgery: use of cochlear nerve action potential monitoring for hearing preservation","volume":"21","author":"Jackson","year":"2000"},{"key":"b14-0270009","series-title":"J Clin Neurophysiol","first-page":"396","article-title":"Mechanisms of intraoperative brainstem auditory evoked potential changes","volume":"19","author":"Legatt","year":"2002"},{"key":"b15-0270009","series-title":"Am J Otol","first-page":"112","article-title":"Comparison of response amplitude versus stimulation threshold in predicting early postoperative facial nerve function after acoustic neuroma resection","volume":"19","author":"Mandpe","year":"1998"},{"key":"b16-0270009","series-title":"J Neurosurg","first-page":"760","article-title":"Nimodipine-induced improved survival rate of facial motor neurons following intracranial transection of the facial nerve in the adult rat","volume":"90","author":"Mattsson","year":"1999"},{"key":"b17-0270009","series-title":"J Comp Neurol","first-page":"106","article-title":"Nimodipine promotes regeneration and functional recovery after intracranial facial nerve crush","volume":"437","author":"Mattsson","year":"2001"},{"key":"b18-0270009","series-title":"J Neurosurg","first-page":"1013","article-title":"Auditory evoked potentials recorded from the cochlear nucleus and its vicinity in man","volume":"59","author":"Moller","year":"1983"},{"key":"b19-0270009","series-title":"Otolaryngol Head Neck Surg","first-page":"179","article-title":"Committee on Hearing and Equilibrium guidelines for the evaluation of hearing preservation in acoustic neuroma (vestibular schwannoma)","volume":"113","author":"Monsell","year":"1995"},{"key":"b20-0270009","series-title":"Otolaryngol Head Neck Surg","first-page":"703","article-title":"Hearing preservation in acoustic neuroma surgery: value of monitoring cochlear nerve action potentials","volume":"111","author":"Nedzelski","year":"1994"},{"key":"b21-0270009","series-title":"Otol Neurotol","first-page":"728","article-title":"Facial nerve monitoring parameters as a predictor of postoperative facial nerve outcomes after vestibular schwannoma resection","volume":"26","author":"Neff","year":"2005"},{"key":"b22-0270009","series-title":"Audiol Neurootol","first-page":"58","article-title":"Intraoperative cochlear nerve monitoring in vestibular schwannoma surgery\u2014does it really affect hearing outcome?","volume":"13","author":"Piccirillo","year":"2008"},{"key":"b23-0270009","series-title":"Neurosurgery","first-page":"392","article-title":"Acoustic (loudspeaker) facial electromyographic monitoring: Part 1. Evoked electromyographic activity during acoustic neuroma resection","volume":"19","author":"Prass","year":"1986"},{"key":"b24-0270009","series-title":"J Neurosurg","first-page":"826","article-title":"Train time as a quantitative electromyographic parameter for facial nerve function in patients undergoing surgery for vestibular schwannoma","volume":"106","author":"Prell","year":"2007"},{"key":"b25-0270009","series-title":"Am J Otol","first-page":"653","article-title":"Direct cochlear nerve action potentials as an aid to hearing preservation in middle fossa acoustic neuroma resection","volume":"17","author":"Roberson","year":"1996"},{"key":"b26-0270009","series-title":"J Neurosurg","first-page":"586","article-title":"Continuous electromyography monitoring of motor cranial nerves during cerebellopontine angle surgery","volume":"93","author":"Romstock","year":"2000"},{"key":"b27-0270009","series-title":"Can J Neurol Sci","first-page":"68","article-title":"Cochlear nerve monitoring during cerebellopontine angle operations","volume":"15","author":"Rowed","year":"1988"},{"key":"b28-0270009","series-title":"J Neurosurg","first-page":"527","article-title":"Improved preservation of hearing and facial nerve function in vestibular schwannoma surgery via the retrosigmoid approach in a series of 200 patients","volume":"105","author":"Samii","year":"2006"},{"key":"b29-0270009","series-title":"Neurosurgery","first-page":"684","article-title":"Management of 1000 vestibular schwannomas (acoustic neuromas): the facial nerve\u2014preservation and restitution of function","volume":"40","author":"Samii","year":"1997"},{"key":"b30-0270009","series-title":"Neurosurgery","first-page":"92","article-title":"The influence of prophylactic vasoactive treatment on cochlear and facial nerve functions after vestibular schwannoma surgery: a prospective and open-label randomized pilot study","volume":"61","author":"Scheller","year":"2007"},{"key":"b31-0270009","series-title":"Zentralbl Neurochir","first-page":"103","article-title":"Delayed facial nerve paresis following acoustic neuroma resection and postoperative vasoactive treatment","volume":"65","author":"Scheller","year":"2004"},{"key":"b32-0270009","series-title":"Neurol Res","first-page":"775","article-title":"Nimodipine ameliorates trauma-induced cochlear neuronal death","volume":"24","author":"Sekiya","year":"2002"},{"key":"b33-0270009","series-title":"Acta Neurochir (Wien)","first-page":"235","article-title":"Intraoperative facial nerve monitoring (IFNM) predicts facial nerve outcome after resection of vestibular schwannoma","volume":"140","author":"Sobottka","year":"1998"},{"key":"b34-0270009","series-title":"J Neurosurg","first-page":"1083","article-title":"The facial nerve in medial acoustic neuromas","volume":"97","author":"Strauss","year":"2002"},{"key":"b35-0270009","series-title":"Am J Otol","first-page":"63","article-title":"Tympanic and transtympanic electrocochleography in acoustic neuroma and vestibular nerve section surgery","volume":"14","author":"Winzenburg","year":"1993"},{"key":"b1-0270009","series-title":"J Neurosci","first-page":"1041","article-title":"Nimodipine accelerates axonal sprouting after surgical repair of rat facial nerve","volume":"16","author":"Angelov","year":"1996"},{"key":"b2-0270009","series-title":"Laryngoscope","first-page":"1911","article-title":"Assessment of real-time clinical facial function during vestibular schwannoma resection","volume":"110","author":"Axon","year":"2000"},{"key":"b3-0270009","series-title":"Science","first-page":"382","article-title":"Far-field acoustic response: origins in the cat","volume":"189","author":"Buchwald","year":"1975"},{"key":"b4-0270009","series-title":"Skull Base Surg","first-page":"1","article-title":"Changes in directly recorded cochlear nerve compound action potentials during acoustic tumor surgery","volume":"4","author":"Colletti","year":"1994"},{"key":"b5-0270009","series-title":"Skull Base Surg","first-page":"187","article-title":"Intraoperative monitoring for hearing preservation and restoration in acoustic neuroma surgery","volume":"10","author":"Colletti","year":"2000"},{"key":"b6-0270009","series-title":"Otol Neurotol","first-page":"826","article-title":"A comparison of direct eighth nerve monitoring and auditory brainstem response in hearing preservation surgery for vestibular schwannoma","volume":"25","author":"Danner","year":"2004"},{"key":"b7-0270009","series-title":"Otol Neurotol","first-page":"388","article-title":"Predictive factors of long-term facial nerve function after vestibular schwannoma surgery","volume":"23","author":"Fenton","year":"2002"},{"key":"b8-0270009","series-title":"Neurosurgery","first-page":"1140","article-title":"Quantitative parameters of intraoperative electromyography predict facial nerve outcomes for vestibular schwannoma surgery","volume":"46","author":"Goldbrunner","year":"2000"},{"key":"b9-0270009","series-title":"J Neurocytol","first-page":"241","article-title":"Nimodipine maintains in vivo the increase in GFAP and enhances the astroglial ensheathment of surviving motoneurons in the rat following permanent target deprivation","volume":"26","author":"Guntinas-Lichius","year":"1997"},{"key":"b10-0270009","series-title":"Mayo Clin Proc","first-page":"92","article-title":"Improved preservation of facial nerve function with use of electrical monitoring during removal of acoustic neuromas","volume":"62","author":"Harner","year":"1987"},{"key":"b11-0270009","series-title":"Neurology","first-page":"1551","article-title":"Effect of BAEP monitoring on hearing preservation during acoustic neuroma resection","volume":"42","author":"Harper","year":"1992"},{"key":"b12-0270009","series-title":"Otolaryngol Head Neck Surg","first-page":"146","article-title":"Facial nerve grading system","volume":"93","author":"House","year":"1985"},{"key":"b13-0270009","series-title":"Am J Otol","first-page":"249","article-title":"Acoustic neuroma surgery: use of cochlear nerve action potential monitoring for hearing preservation","volume":"21","author":"Jackson","year":"2000"},{"key":"b14-0270009","series-title":"J Clin Neurophysiol","first-page":"396","article-title":"Mechanisms of intraoperative brainstem auditory evoked potential changes","volume":"19","author":"Legatt","year":"2002"},{"key":"b15-0270009","series-title":"Am J Otol","first-page":"112","article-title":"Comparison of response amplitude versus stimulation threshold in predicting early postoperative facial nerve function after acoustic neuroma resection","volume":"19","author":"Mandpe","year":"1998"},{"key":"b16-0270009","series-title":"J Neurosurg","first-page":"760","article-title":"Nimodipine-induced improved survival rate of facial motor neurons following intracranial transection of the facial nerve in the adult rat","volume":"90","author":"Mattsson","year":"1999"},{"key":"b17-0270009","series-title":"J Comp Neurol","first-page":"106","article-title":"Nimodipine promotes regeneration and functional recovery after intracranial facial nerve crush","volume":"437","author":"Mattsson","year":"2001"},{"key":"b18-0270009","series-title":"J Neurosurg","first-page":"1013","article-title":"Auditory evoked potentials recorded from the cochlear nucleus and its vicinity in man","volume":"59","author":"Moller","year":"1983"},{"key":"b19-0270009","series-title":"Otolaryngol Head Neck Surg","first-page":"179","article-title":"Committee on Hearing and Equilibrium guidelines for the evaluation of hearing preservation in acoustic neuroma (vestibular schwannoma)","volume":"113","author":"Monsell","year":"1995"},{"key":"b20-0270009","series-title":"Otolaryngol Head Neck Surg","first-page":"703","article-title":"Hearing preservation in acoustic neuroma surgery: value of monitoring cochlear nerve action potentials","volume":"111","author":"Nedzelski","year":"1994"},{"key":"b21-0270009","series-title":"Otol Neurotol","first-page":"728","article-title":"Facial nerve monitoring parameters as a predictor of postoperative facial nerve outcomes after vestibular schwannoma resection","volume":"26","author":"Neff","year":"2005"},{"key":"b22-0270009","series-title":"Audiol Neurootol","first-page":"58","article-title":"Intraoperative cochlear nerve monitoring in vestibular schwannoma surgery\u2014does it really affect hearing outcome?","volume":"13","author":"Piccirillo","year":"2008"},{"key":"b23-0270009","series-title":"Neurosurgery","first-page":"392","article-title":"Acoustic (loudspeaker) facial electromyographic monitoring: Part 1. Evoked electromyographic activity during acoustic neuroma resection","volume":"19","author":"Prass","year":"1986"},{"key":"b24-0270009","series-title":"J Neurosurg","first-page":"826","article-title":"Train time as a quantitative electromyographic parameter for facial nerve function in patients undergoing surgery for vestibular schwannoma","volume":"106","author":"Prell","year":"2007"},{"key":"b25-0270009","series-title":"Am J Otol","first-page":"653","article-title":"Direct cochlear nerve action potentials as an aid to hearing preservation in middle fossa acoustic neuroma resection","volume":"17","author":"Roberson","year":"1996"},{"key":"b26-0270009","series-title":"J Neurosurg","first-page":"586","article-title":"Continuous electromyography monitoring of motor cranial nerves during cerebellopontine angle surgery","volume":"93","author":"Romstock","year":"2000"},{"key":"b27-0270009","series-title":"Can J Neurol Sci","first-page":"68","article-title":"Cochlear nerve monitoring during cerebellopontine angle operations","volume":"15","author":"Rowed","year":"1988"},{"key":"b28-0270009","series-title":"J Neurosurg","first-page":"527","article-title":"Improved preservation of hearing and facial nerve function in vestibular schwannoma surgery via the retrosigmoid approach in a series of 200 patients","volume":"105","author":"Samii","year":"2006"},{"key":"b29-0270009","series-title":"Neurosurgery","first-page":"684","article-title":"Management of 1000 vestibular schwannomas (acoustic neuromas): the facial nerve\u2014preservation and restitution of function","volume":"40","author":"Samii","year":"1997"},{"key":"b30-0270009","series-title":"Neurosurgery","first-page":"92","article-title":"The influence of prophylactic vasoactive treatment on cochlear and facial nerve functions after vestibular schwannoma surgery: a prospective and open-label randomized pilot study","volume":"61","author":"Scheller","year":"2007"},{"key":"b31-0270009","series-title":"Zentralbl Neurochir","first-page":"103","article-title":"Delayed facial nerve paresis following acoustic neuroma resection and postoperative vasoactive treatment","volume":"65","author":"Scheller","year":"2004"},{"key":"b32-0270009","series-title":"Neurol Res","first-page":"775","article-title":"Nimodipine ameliorates trauma-induced cochlear neuronal death","volume":"24","author":"Sekiya","year":"2002"},{"key":"b33-0270009","series-title":"Acta Neurochir (Wien)","first-page":"235","article-title":"Intraoperative facial nerve monitoring (IFNM) predicts facial nerve outcome after resection of vestibular schwannoma","volume":"140","author":"Sobottka","year":"1998"},{"key":"b34-0270009","series-title":"J Neurosurg","first-page":"1083","article-title":"The facial nerve in medial acoustic neuromas","volume":"97","author":"Strauss","year":"2002"},{"key":"b35-0270009","series-title":"Am J Otol","first-page":"63","article-title":"Tympanic and transtympanic electrocochleography in acoustic neuroma and vestibular nerve section surgery","volume":"14","author":"Winzenburg","year":"1993"}],"container-title":["Neurosurgical Focus"],"original-title":[],"link":[{"URL":"https:\/\/thejns.org\/view\/journals\/neurosurg-focus\/27\/4\/article-pE9.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/neurosurg-focus\/27\/4\/article-pE9.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/neurosurg-focus\/27\/4\/article-pE9.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,30]],"date-time":"2026-05-30T08:24:49Z","timestamp":1780129489000},"score":1,"resource":{"primary":{"URL":"https:\/\/thejns.org\/view\/journals\/neurosurg-focus\/27\/4\/article-pE9.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,10]]},"references-count":70,"journal-issue":{"issue":"4"},"URL":"https:\/\/doi.org\/10.3171\/2009.8.focus09144","relation":{},"ISSN":["1092-0684"],"issn-type":[{"value":"1092-0684","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,10]]}}}