Hearing preservation in vestibular schwannoma surgery: fact or fantasy?

Abstract

This study reviews 57 papers dealing with the issue of hearing preservation in vestibular schwannoma surgery published in otolaryngologic and neurosurgical literature between theyears 1977 and 1994. The authors', in this review, have made an attempt to verify whether the claims of hearing preservation are real, whether there is a price to be paid in terms of morbidity and whether there are univocal criteria for reporting results. The review shows that there is a wide disarray in reporting hearing results and the claims of hearing preservation are often unreal and misleading. On retabulating the results of a few series according to the minimal prerequisites for normal hearing (PTA ≤3O dB and SDS ≥70 per cent) and according to other various commonly reported criteria, it became evident that rates of hearing preservation differeda lot depending upon criteria. While any measurable hearing could be preserved in many cases, only a few had normal hearing preserved.

Analysis of Hearing Preservation and Facial Nerve Function for Patients Undergoing Vestibular Schwannoma Surgery: The Middle Cranial Fossa Approach versus the Retrosigmoid Approach – Personal Experience and Literature Review

“…These challenges increased in severity as a function of a higher number of small size schwannomas that were observed after the introduction Hearing and Facial Nerve Outcomes in Vestibular Schwannoma Surgery of the magnetic resonance imaging (MRI) [Sanna et al, 1995;Brackmann et al, 2000;Noudel et al, 2009].…”

“…For example, maintenance of the preoperative hearing level can be considered as hearing preservation. The levels of hearing in the postoperative period can also be categorized as normal [pure-tone threshold averages (PTA) ^ 30 dB and speech discrimination score (SDS) 6 70%], serviceable (PTA ^ 50 and SDS 6 50%), and measurable (any measurable hearing) [Sanna et al, 1995]. Preserved hearing can also be defined as any one of the aforementioned categories.…”

“…Herein, the modified Sanna hearing classification system was used to characterize hearing preservation [Kanzaki et al, 2003]. Differently from the classification by the AAO-HNS, which used frequencies of 500, 1000, 2000, and 3000 Hz for the calculation of PTA, this classification is based on the frequencies 500, 1000, 2000, and 4000 Hz because this last frequency is crucial for speech intelligibility [Sanna et al, 1995]. Additional advantages of such a system are that this classification divides the postoperative results into 6 separate categories, which facilitates differentiation of the outcomes.…”

Contemporary Surgical Management of Vestibular Schwannomas

“…5,3,30 In this system, pure tone average and speech discrimination score are used to categorize hearing as normal, good, fair, serviceable, measurable, and deaf as listed in Table 3. Tumor size and hearing classification according to this system were used to select candidates for hearing preservation surgery (HPS).…”

The effect of the 2003 Consensus Reporting Standards on publications describing patients with vestibular schwannoma treated with stereotactic radiosurgery

“…The H-B grading system has been adopted successfully worldwide for many years, and the Consensus Reporting System continues to support its use for facial nerve function. Multiple different grading systems have been developed to assess and classify hearing function, including the AAO-HNS, Gardner-Robertson, and the system proposed by Sanna et al 11 The Guidelines propose yet a new classification system. However, all of these different classifications are commonly based on the PTA and the SDS scores, and any reader can translate the reported PTA and SDS scores into the preferred classification system, as long as the publications on VS continue to include the PTA and SDS scores, as most articles already do.…”