Abstract
Tinnitus is one of the most common symptoms before and/or after the surgical removal of a vestibular schwannoma (VS) affecting almost half of the patients. Although there is increasing evidence for the association of hearing impairment and VS-associated tinnitus, the effect of hearing deterioration due to surgery and its relation to the postoperative tinnitus (postTN) is poorly investigated. This knowledge, however, might (i) enlighten the pathophysiology of VS-associated tinnitus (i.e., peripheral or central origin) and (ii) improve preoperative patient counseling. The aim of this study was to understand the predisposition factors for a postTN in relation to hearing outcome after surgery. This retrospective study analyzed the presence of tinnitus in 208 patients with unilateral VS before and after surgical removal. A binomial logistic regression was performed to ascertain the effect of pre- and postoperative hearing as well as age, gender, tumor side, and size, and intraoperative cochlear nerve resection (CNR) on the likelihood of postoperative VS-associated tinnitus. Preoperative tinnitus was the strongest predictor of postTN. In addition, deterioration of functional hearing was increasing, while functional deafferentation (i.e., postoperative hearing loss) of non-functional hearing was reducing the risk of postTN. At the same time, patients with no preoperative tinnitus but complete hearing loss had the lowest risk to suffer from postTN. Patient age, gender, tumor side, and size as well as CNR played a subordinate role. While the presence of preoperative tinnitus was the strongest predictor of postTN, there is a distinct relationship between hearing outcome and postTN depending on the preoperative situation. Functional or anatomical deafferentation due to surgical tumor removal does not prevent postTN per se.
Highlights
Tinnitus occurs in 63–75% of patients with unilateral vestibular schwannoma (VS) [1, 2] and in 10% of these patients it is the presenting symptom [3]
While the presence of preoperative tinnitus was the strongest predictor of postoperative tinnitus (postTN), there is a distinct relationship between hearing outcome and postTN depending on the preoperative situation
All patients underwent a surgical removal of the tumor via the retrosigmoidal-transmeatal approach supported by continuous neuromonitoring of the brainstem auditory-evoked potentials (BAEP) aiming anatomical preservation of the cochlear nerve
Summary
Tinnitus occurs in 63–75% of patients with unilateral vestibular schwannoma (VS) [1, 2] and in 10% of these patients it is the presenting symptom [3]. The neuroplastic changes are supposed to cause a neuronal hyperexcitability for the residual auditory input resulting in the subjective misperception [10,11,12,13]. In line with this pathophysiological concept, an association between hearing impairment, i.e., the clinical correlate of damage to the cochlear nerve, and the occurrence of tinnitus in VS patients is expected. It was not until recently, that hearing impairment has been shown to predict preoperative VS-associated tinnitus [2]. Some authors suggest cochlear nerve resection (CNR) for tinnitus elimination [14, 16]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
