Contralateral hearing loss after acoustic neuroma surgery

Retrospective Investigation of Contralateral Hearing Thresholds of Patients With Sporadic Vestibular Schwannoma

OBJECTIVE

The aim of this study was to investigate the contralateral hearing of patients with sporadic vestibular schwannoma (VS).

STUDY DESIGN

Retrospective cohort study.

SETTING

Pure-tone audiograms of the contralateral ear from patients with a wait-and-scan strategy were compared to the ones who received therapy. Due to a possible bias caused by the therapy, hearing thresholds before and after radiotherapy or surgery were compared separately with the wait-and-scan group.

METHODS

From 1979 to 2017, 508 patients with sporadic VS could be included in the study. Of these, 240 received regular controls in the sense of wait-and-scan, 72 underwent radiotherapy (63 audiograms before and 43 after radiotherapy), and 196 had a surgery (186 audiograms before and 146 after surgery). Age-normalized hearing thresholds of the contralateral ear from patients with a wait-and-scan strategy were compared to ones who received therapy. In addition, hearing thresholds were compared to norm values.

RESULTS

There was no evidence for a difference in the contralateral hearing of patients with sporadic VS between the wait-and-scan and therapy groups. The mean difference of hearing thresholds in our sample to norm values was found to be larger for the high frequencies and more pronounced in male patients.

CONCLUSION

There was no evidence for a difference in the contralateral hearing loss of patients with sporadic VS between the wait-and-scan and therapy groups. However, there was some indirect indication of poorer contralateral hearing in all patients with sporadic VS compared to normative values.

Contralateral sensorineural hearing loss after vestibular schwannoma surgery

INTRODUCTION

Contralateral sensorineural hearing loss (CSNHL) after vestibular schwannoma (VS) is a severe complication, especially in those cases in which hearing preservation in the operated side was not possible. There are several theories that attempt to explain this issue, but there is no established guideline of treatment.

MATERIAL AND METHODS

We report 4 patients treated in our institution who developed a severe CSNHL after surgery.

RESULTS

Of the 185 cases of VS treated with surgery, 4 patients (2.2%) developed a CSNHL after VS surgery. After medical treatment, partial recovery of hearing occurred in one patient the other 3 patients presented a well-established severe SNHL.

CONCLUSIONS

Established treatment guidelines do not exist, but the use of high doses of corticosteroids has been recommended and cochlear implant in cases with no recovery and complete hearing loss may be useful.

Contralateral hearing loss and facial palsy in an operated case of vestibular schwannoma-Case report

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Rare complication of contralateral hearing loss and facial palsy following vestibular schwannoma surger.

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The exact cause is uncertain and various theories are proposed to ascertain the cause.

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Treatment options are limited.

Introduction

Contralateral ear hearing loss (CHL) is an extremely rare but a potentially devastating complication in a patient with already compromised hearing due to a Vestibular schwannoma (VS). Our patient had CHL accompanied by contralateral facial palsy. Our case is only the second case reported in literature to the best of our knowledge.

Presentation of case

A 55-year elderly male presented with right sided sensorineural hearing loss, cerebellar signs and Grade II House & Brackmann (H&B) facial nerve weakness for last1-year. Magnetic resonance imaging (MRI) scan revealed a large right sided vestibular schwannoma (VS) with severe compression of the ipsilateral pons. The pre-operative pure tone audiometry (PTA) documented severe sensory neural hearing loss (SNHL) on the right side along with mild SNHL on the left side. A right retromastoid suboccipital craniotomy was performed and VS was completely excised. The ipsilateral facial nerve was preserved anatomically. On the 4th post-operative day he developed severe pain and tinnitus in left ear. In the next 24-h there were hearing loss and grade II facial nerve paresis. The PTA done on the 5th post-operative day revealed severe SNHL on both sides. He was managed conservatively with steroids and vasodilators. At 6-months of follow-up the left side hearing loss and facial weakness had significantly recovered. The PTA showed significant improvement in the left side SNHL

Discussion

Contralateral hearing disturbance with contralateral facial palsy after acoustic neuroma surgery is extremely rare. The exact etiopathogenesis of this unusual phenomenon is not clear and various theories have been proposed. There is no standard recommendation for treatment of these rare complications and the etiology remains obscure.

Conclusion

Hearing loss and facial palsy on the contralateral side after VS surgery is extremely rare. It is imperative that this rare complication should be considered following VS surgery.

The incidence of high-frequency hearing loss after microvascular decompression for trigeminal neuralgia, glossopharyngeal neuralgia, or geniculate neuralgia

OBJECT

The primary aim of this study was to evaluate the incidence and discuss the pathogenesis of high-frequency hearing loss (HFHL) after microvascular decompression (MVD) for trigeminal neuralgia (TGN), glossopharyngeal neuralgia (GPN), or geniculate neuralgia (GN).

METHODS

The authors analyzed preoperative and postoperative audiogram data and brainstem auditory evoked potentials (BAEPs) from 93 patients with TGN, 6 patients with GPN, and 8 patients with GN who underwent MVD. Differences in pure tone audiometry > 10 dB at frequencies of 0.25, 0.5, 1, 2, 4, and 8 kHz were calculated preoperatively and postoperatively for both the ipsilateral and the contralateral sides. Intraoperative monitoring records were analyzed and compared with the incidence of HFHL, which was defined as a change in pure tone audiometry > 10 dB at frequencies of 4 and 8 kHz.

RESULTS

The incidence of HFHL was 30.84% on the side ipsilateral to the surgery and 20.56% on the contralateral side. Of the 47 patients with HFHL, 20 had conductive hearing loss, and 2 experienced nonserviceable hearing loss after the surgery. The incidences of HFHL on the ipsilateral side at 4 and 8 kHz were 17.76% and 25.23%, respectively, and 8.41% and 15.89%, respectively, on the contralateral side. As the audiometric frequency increased, the number of patients with hearing loss increased. No significant postoperative difference was found between patients with and without HFHL in intraoperative BAEP waveforms. Sex, age, and affected side were not associated with an increase in the incidence of hearing loss.

CONCLUSIONS

High-frequency hearing loss occurred after MVD for TGN, GPN, or GN, and the greatest incidence occurred on the ipsilateral side. This hearing loss may be a result of drill-induced noise and/or transient loss of cerebrospinal fluid during the course of the procedure. Changes in intraoperative BAEP waveforms were not useful in predicting HFHL after MVD. Repeated postoperative audiological examinations may be useful in assessing the prognosis of HFHL.