Therapeutic approach in managing patients with large vestibular aqueduct syndrome (LVAS)

Cochlear implantation in adults and pediatrics with enlarged vestibular aqueduct: a systematic review on the surgical findings and patients' performance

PURPOSE

Cochlear implantation (CI) has been considered a safe and effective management option for patients with severe to profound hearing loss. Patients with enlarged vestibular aqueduct (EVA) could be challenging with some variations in surgical approaches, intraoperative surgical notes, and clinical outcomes. This study aimed to  review the surgical and clinical outcomes of cochlear implantation among patients with EVA.

MATERIALS AND METHODS

A systematic literature search was carried out in five major databases. All original studies reporting cochlear implantation in patients with EVA were included for qualitative data synthesis. The risk of bias was independently assessed through the National Intuitional of Health tool. The review protocol was registered in PROSPERO (reference number: CRD42021225900).

RESULTS

A total of 34 studies with 4035 subjects were included. Of them, 853 (21.14%) had EVA and underwent CI. Mondini malformation was the most frequently associated anomaly (n = 78, 11.1%). Unilateral implantation was performed in 258 cases while bilateral in 119 subjects. Postoperative complications included CSF/perilymph gusher (n = 112), CSF oozing (n = 18), and partial electrode insertion (n = 6). Closing the cochleostomy with temporalis fascia, muscle, connective tissue, or fibrin glue was the most frequently reported approach to manage CSF/perilymph gusher (n = 67, 56.7%) while packing was performed in six patients.

CONCLUSION

Patients with EVA demonstrated audiometric and speech performance improvement after CI. However, many patients had intra- or postoperative complications. Further research is needed as the outcomes may be affected by associated temporal bone pathology, the timing of implant, and hearing condition.

Cochlear Implantation in Pediatric Patients With Enlarged Vestibular Aqueduct: A Systematic Review

OBJECTIVE(S)

To describe cochlear implantation (CI) outcomes, with speech perception, auditory, language, and parent-reported auditory and speech behaviors, in children with an enlarged vestibular aqueduct (EVA) and incomplete partition type 2 (IP-II) and compare to control children without inner ear malformations (IEMs) and to determine cerebrospinal fluid gusher rates and effect on outcomes.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

MEDLINE, Embase, Cochrane, and CINAHL databases were searched from inception to February 2020. Studies reporting relevant outcomes in children with EVA or EVA + IP-II and controls without IEMs undergoing CI were included. Mean differences in speech perception, auditory, and language scores between cases and controls were meta-analyzed. Gusher rates were determined by proportion meta-analyses.

RESULTS

Of 214 identified articles, 42 met inclusion criteria, evaluating 775 cases and 2,191 controls. Of -cases, 578 (74.6%) had EVA and 197 (25.4%) had EVA + IP-II. Cases showed a significant improvement in speech perception, auditory and language performance, comparable to controls. Parent-reported auditory and speech production behaviors outcomes were positive among cases and comparable to controls. Pooled gusher proportions in EVA and EVA + IP-II cases were 27.7% (95% CI: 17.6-39.1) and 48.6% (95% CI: 28.6-69.0), respectively, with a proportion difference of 20.9% (95% CI: 11.0-30.1). Gusher occurrence did not impact speech perception or language outcomes.

CONCLUSION

Outcomes in children with EVA or EVA + IP-II undergoing CI are favorable and largely comparable to outcomes in children with hearing loss undergoing CI without IEMs. Intraoperative gusher is more prevalent among children with EVA + IP-II as compared to iEVA. Gusher does not influence speech perception and language development outcomes.

LEVEL OF EVIDENCE

NA Laryngoscope, 2021.

Investigation of DFNB4 SLC26A4 mutation in patients with enlarged vestibular aquaduct

OBJECTIVES

Mutations of the SLC26A4 gene causing enlarged vestibular aqueduct (EVA) syndrome have not yet been fully elucidated. The study aimed to investigate SLC26A4 mutations in patients with EVA syndrome in the Turkish population. Identifying these mutations may play an essential role in determining the prognosis, follow-up, and management options of these patients.

METHODS

Whole exome sequencing and/or Sanger sequencing of SLC26A4 in 22 patients with sensorineural hearing loss associated with isolated EVA without inner ear anomalies, and 22 controls were performed.

RESULTS

Twenty-two patients and 22 control subjects were included in the study. The onset of hearing loss was pre-lingual in 15 patients, and post-lingual in 7. The mean (standard deviation) vestibular aqueduct width of the patients was 3.23 mm (1.28). Twenty SLC26A4 variants, 15 of them unique, were identified in 22 patients. Among them, seven variants were heterozygous, and 13 were homozygous. The variants p.E37X (c.109G > T), p.Y27H (c.79T > C), p.C706Y (c.2117G > A) have not been previously reported.

CONCLUSION

The detection of rare and previously unreported mutations in our study showed that studies with a larger number of patients with EVA might reveal more role of the SLC26A4 gene. Besides, to understand the etiopathogenesis of the disease, other related genes also should be investigated.

Enlarged Vestibular Aqueduct and Cochlear Implants: The Effect of Early Counseling on the Length of Time Between Candidacy and Implantation

OBJECTIVE

To determine if discussing cochlear implantation (CI) with patients with enlarged vestibular aqueducts (EVA) and their families before reaching audiological criteria for CI candidacy effects the length of time between reaching audiological candidacy and CI surgery, and to describe the universal newborn hearing screening (UNHS) results and communication modality in this sample.

PATIENTS

Forty-two patients (25 females) with confirmed EVA and cochlear implants.

INTERVENTION(S)

Diagnostic CI visit.

MAIN OUTCOME MEASURES

The primary outcome measure is the difference in length of time between reaching audiological candidacy for CI and surgical implantation between those who had preliminary discussions regarding CI with their medical and healthcare providers before reaching audiological candidacy versus who had discussions after reaching candidacy. The secondary outcome measure is the result of the UNHS and primary mode of communication used by each patient.

RESULTS

Discussing CI before reaching audiological candidacy was associated with a significantly shorter duration between reaching audiological candidacy and receiving CI (median = 3.1 mo; interquartile range [IQR] = 1.7-5.4) as compared with discussing CI after reaching candidacy (median = 5.8 mo; IQR = 3.2-11.2; p = 0.012). Participants born after the implementation of the UNHS, 16 of 24 patients referred on one or both ears. Communication modalities were evenly divided between utilizing sign-support English and oral/aural communicators only.

CONCLUSIONS

Discussion of CI in patients with EVA before reaching audiological candidacy reduces the amount of time the child is without adequate auditory access and contributes to a constructive and interactive preparatory experience.

Large vestibular aqueduct syndrome: Impedance changes over time with different cochlear implant electrode arrays

OBJECTIVES

The aim of this study was to assess if large vestibular aqueduct syndrome (LVAS), with the increase in perilymphatic pressure, affects impedance changes over time with different types of Cochlear(®) implant electrode arrays Contour, Straight, and CI 422. To report speech perception outcomes for these cochlear implant recipients.

METHODS

Retrospective case review of impedance levels and categories of auditory performance. Impedance data were collected at switch on, 1 month, 3, 6, 12, and 24 months after cochlear implantation and compared with control (non-LVAS cochlear implant recipient) data for each array type. Forty-seven patients with exclusive LVAS and no other vestibulocochlear abnormalities or other identifiable cause of deafness were eligible for inclusion in the study.

RESULTS

In LVAS patients, there was a significant difference in impedance between the three types of device (P < 0.0001). Time since switch on was associated with a decrease in impedance for all three devices (P < 0.0001). The mean impedance reduced between switch on and 1 month and remained relatively constant thereafter. Sound variation with softening of sounds was seen in four CI 422 (Straight Research Array) recipients due to ongoing fluctuations in electrode compliance.

DISCUSSION

For all three array types, there was no significant difference in the mean impedance between the LVAS patients and controls over the first 12 months. In keeping with previous studies cochlear implant recipients with LVAS hear very well through the cochlear implant.

Timing of surgical intervention with cochlear implant in patients with large vestibular aqueduct syndrome

Objectives

(1) To report the speech perception and intelligibility results of Mandarin-speaking patients with large vestibular aqueduct syndrome (LVAS) after cochlear implantation (CI); (2) to compare their performance with a group of CI users without LVAS; (3) to understand the effects of age at implantation and duration of implant use on the CI outcomes. The obtained data may be used to guide decisions about CI candidacy and surgical timing.

Methods

Forty-two patients with LVAS participating in this study were divided into two groups: the early group received CI before 5 years of age and the late group after 5. Open-set speech perception tests (on Mandarin tones, words and sentences) were administered one year after implantation and at the most recent follow-up visit. Categories of auditory perception (CAP) and Speech Intelligibility Rating (SIR) scale scores were also obtained.

Results

The patients with LVAS with more than 5 years of implant use (18 cases) achieved a mean score higher than 80% on the most recent speech perception tests and reached the highest level on the CAP/SIR scales. The early group developed speech perception and intelligibility steadily over time, while the late group had a rapid improvement during the first year after implantation. The two groups, regardless of their age at implantation, reached a similar performance level at the most recent follow-up visit.

Conclusion

High levels of speech performance are reached after 5 years of implant use in patients with LVAS. These patients do not necessarily need to wait until their hearing thresholds are higher than 90 dB HL or PB word score lower than 40% to receive CI. They can do it “earlier” when their speech perception and/or speech intelligibility do not reach the performance level suggested in this study.

Hyperbaric oxygen therapy for sudden sensorineural hearing loss in large vestibular aqueduct syndrome

Introduction:

We report the first use in Australia of hyperbaric oxygen therapy for sudden hearing loss following head trauma in a child with large vestibular aqueduct syndrome.

Case report:

A 12-year-old boy with large vestibular aqueduct syndrome presented with significant hearing loss following head trauma. He was treated with steroids and hyperbaric oxygen therapy, with good improvement of hearing thresholds on audiography. This case represents the first reported use of hyperbaric oxygen therapy for this indication in Australia, following a few previous reports of patients in Japan. We review the literature on management of acute sensorineural hearing loss in large vestibular aqueduct syndrome. The reported case demonstrates a potentially beneficial therapy for a rare condition that usually results in an inevitable decline in hearing.

Conclusion:

Hyperbaric oxygen therapy can be tolerated well by children, and may represent a potential treatment for sudden sensorineural hearing loss in patients with large vestibular aqueduct syndrome.