Regression of Endolymphatic Hydrops in Patient With Meniere's Disease Treated With Vestibular Neurectomy: A Case Report

Vestibular neurectomy is an effective method eliminating vertigo attacks in patients suffering from disabling Meniere's disease with no clinical improvement despite conservative and intratympanic therapy. Magnetic resonance imaging allows in vivo evaluation of changes manifesting in the inner ear after treatment; however, downgrading of the endolymphatic hydrops after vestibular neurectomy had not been previously described in the literature. In the present article, a case of a patient with unilateral severe Meniere's disease treated with selective vestibular nerve section from middle fossa approach was described. Clinical symptoms and audiovestibular tests were evaluated before and 13 months after the surgery. Complete resolution of vertigo episodes and hearing preservation was achieved. Magnetic resonance imaging was performed before and after the surgery using a 3 Tesla scanner with dedicated protocol after intravenous administration of gadolinium contrast agent. In the follow-up examination, regression of the cochlear and vestibular endolymphatic hydrops was visualized, which may suggest processes occurring in the labyrinth as a result of the vestibular efferent fibers section.

Selective Vestibular Neurectomy through the Presigmoid Retrolabyrinthine Approach in the Treatment of Meniere's Disease

BACKGROUND

Meniere's disease (MD) is a disabling disease, especially in patients who are refractory to medical therapy. Moreover, selective vestibular neurectomy (VN), in these selected cases, can be considered a surgical alternative which preserves hearing function and facial nerve.

METHODS

We retrospectively studied 23 patients with MD diagnosis and history of failed extradural endolymphatic sac surgery (ELSS) who underwent combined micro-endoscopic selective VN, between January 2019 and August 2023, via a presigmoid retrolabyrinthine approach. All patients were stratified according to clinical features, assessing preoperative and postoperative hearing levels and quality of life.

RESULTS

At the maximum present follow-up of 2 years, this procedure is characterized by a low rate of complications and about 90% vertigo control after surgery. No definitive facial palsy or hearing loss was described in this series. One patient required reintervention for a CSF fistula. Statistically significant (p = 0.001) difference was found between the preoperative and the postoperative performance in terms of physical, functional, and emotive scales assessed via the DHI questionnaire.

CONCLUSIONS

Selective VN via a presigmoid retrolabyrinthine approach is a safe procedure for intractable vertigo associated with MD, when residual hearing function still exists. The use of the endoscope and intraoperative neuromonitoring guaranteed a precise result, saving the cochlear fibers and facial nerve. The approach for VN is a familiar procedure to the otolaryngologist, as is lateral skull base anatomy to the neurosurgeon; therefore, the best results are obtained with multidisciplinary teamwork.

Case report: Can cochlear implant stimulation lead to improved balance even after vestibular neurectomy?

Introduction

In a previous manuscript from our research group, the concept of vestibular co-stimulation was investigated in adult subjects who received a cochlear implant (CI). Despite what literature reports state, no signs of vestibular co-stimulation could be observed.

Results

In this case report, it was described how a woman, who previously underwent a neurectomy of the left vestibular nerve and suffers from bilateral vestibulopathy (BVP), reported improved balance whenever her CI on the left was stimulating. Unexpectedly, the sway analyses during posturography indeed showed a clinically relevant improvement when the CI was activated.

Discussion

Vestibular co-stimulation as a side effect of CI stimulation could not be the explanation in this case due to the ipsilateral vestibular neurectomy. It is more likely that the results can be attributed to the electrically restored auditory input, which serves as an external reference for maintaining balance and spatial orientation. In addition, this patient experienced disturbing tinnitus whenever her CI was deactivated. It is thus plausible that the tinnitus increased her cognitive load, which was already increased because of the BVP, leading to an increased imbalance in the absence of CI stimulation.

Quality of Life Following Cochlear Implantation in Patients With Menière's Disease

Background: Menière's disease (MD) is a disorder characterized by auditory and vestibular dysfunction that significantly deteriorates patients' quality of life (QoL). In addition to the management of vestibular symptoms, some patients with bilateral hearing loss meet criteria for cochlear implantation (CI).

Objectives: (1) To assess hearing results and QoL outcomes following CI in patients with MD. (2) To compare these results to a matched control group of patients who had undergone CI. (3) To analyse differences in MD patients who have undergone simultaneous or sequential labyrinthectomy or previous neurectomy.

Methods: A retrospective analysis of a study group of 18 implanted patients with MD and a matched control group of 18 implanted patients without MD, who had CI at a tertiary referral center. Hearing and speech understanding were assessed via pure-tone audiometry (PTA) and disyllabic perception tests in quiet. QoL was assessed via the Nijmegen Cochlear Implant Questionnaire (NCIQ), the Glasgow Benefit Inventory (GBI), the Speech, Spatial and Qualities of Hearing Scale (SSQ₁₂), and the Hearing Implant Sound Quality Index (HISQUI₁₉). The impact of MD ablative surgeries was analyzed in the study group (MD group).

Results: Mean pre-operative PTA thresholds were significantly lower in the MD group (103 vs. 121 dB). A significant improvement in hearing outcomes was observed following CI in both groups (p < 0.001), with a maximum Speech Discrimination Score of 64 and 65% disyllables at 65 dB for the MD and control group, respectively. Subjective outcomes, as measured by the NCIQ, GBI, SSQ₁₂, and HISQUI₁₉ did not significantly differ between groups. In the MD group, despite achieving similar hearing results, QoL outcomes were worse in patients who underwent simultaneous CI and labyrinthectomy compared to the rest of the MD group. Post-operative NCIQ results were significantly better in patients who had undergone a previous retrosigmoid neurectomy when compared to those who had undergone only CI surgery in the subdomains “basic sound perception” (p = 0.038), “speech” (p = 0.005), “activity” (p = 0.038), and “social interactions” (p = 0.038).

Conclusion: Patients with MD and severe hearing loss obtain hearing results and QoL benefits similar to other CI candidates. Delayed CI after labyrinthectomy or vestibular neurectomy can be performed with similar or better results, respectively, to those of other cochlear implanted patients. Patients who undergo simultaneous CI and labyrinthectomy may achieve similar hearing results but careful pre-operative counseling is needed.

The Relationship of Vestibulo-Ocular Reflex With Self-Reported Dizziness Handicap in Patients With Vestibular Deafferentation

The relationship between objective vestibular tests and subjective vestibular tests is a controversial topic. In this study, to contribute to this issue, the vestibulo-ocular reflex features and their relationship with balance perception at long-term follow-up in vestibular neurectomy (VN) and total labyrentectomy patients were evaluated. Prospectively, 19 VN and 18 labyrinthectomy patients were enrolled in this study. Patients underwent video head impulse test (VHIT) as objective vestibular test and dizziness handicap inventory (DHI) as subjective vestibular test when they attended to their control visit follow-up between March and September 2017. Lateral canal corrective saccades were classified as organized pattern and deorganized (scattered) pattern. In our results, the saccade pattern analysis (between organized and deorganized saccades) regarding the DHI scores gave P value as .039 for covert saccade pattern and .050 for overt saccade pattern. Therefore, we conclude that the presence of saccades, their patterns, and amplitudes provide extra information at assessing the results of the VHIT test, and the organized pattern of saccades is related to a stable vestibular system and better balance perception.

Vestibular Neurectomy for Intractable Vertigo: Case Series and Evaluation of Role of Endoscopic Assistance in Retrolabyrinthine Craniotomy

Objective  This study evaluates the utility of endoscopy for retrolabyrinthine vestibular nerve section (RLVNS). Design/Setting  This is a retrospective review for RLVNSs by the senior author. The endoscope's utility was assessed and assigned a grade based on operative findings. Participants/Main Outcome Measures  Fifteen patients (eight males and seven females; 53 and 47%, respectively) were identified with mean age 56.7 years. Indications included Ménière's disease (MD) in 12 of 15 patients (80%), uncompensated vestibular neuritis in 2 patients (13%), and other vestibular neuropathy in 1 patient (7%). Vertigo resolved in 14 of 15 patients (93%). Complications included decreased hearing in two patients (13%) and deep venous thrombosis in one patient (7%). There were no facial nerve complications or mortalities. Results  Sectioning vestibular division of the vestibular-cochlear nerve was achieved without perceived benefit of endoscopy in the 80% of cases (grade 0, n  = 12). Endoscopy was helpful in patients with a small mastoid (grade 1, n  = 2, 13.3%), and deemed necessary where the flocculus of the cerebellum was adherent to the eighth nerve arachnoid at the porus acusticus (grade 2, n  = 1, 6.7%). Conclusion  RLVNS is a safe and efficacious procedure for the treatment of vertigo; the surgical endoscope may be a useful adjunct in selected cases. Patients with MD may expect the greatest benefit from surgery.

Anatomical Factors Influencing Selective Vestibular Neurectomy: A Comparison of Posterior Fossa Approaches

Objectives To identify measurable anatomical factors that may guide the surgical approach for posterior fossa selective vestibular neurectomy (SVN) and predict identification of the vestibulocochlear cleavage (VCC) plane. Study Design Dissection of fixed cadaveric heads through retrolabyrinthine and retrosigmoid-internal auditory canal (RSG-IAC) approaches with measurement of landmarks. Setting Cadaveric dissection model. Main Outcome Measures Area of the Trautmann triangle (TT) and the distance from the posterior semicircular canal to the anterior border of the sigmoid along the posterior Donaldson line (pDL). VCC planes from each approach were calculated and compared. Results Overall mean pDL was 8.53 mm (range: 5-11.5 mm); mean TT area was 124 mm(2) (range: 95-237 mm(2)). The VCC was identified in 63% of ears through the retrolabyrinthine (RVN) approach alone, whereas 37% of ears required the RSG-IAC approach. In ears requiring IAC dissection, the VCC was found within 1 to 2 mm distal to the porus. The pDL (p < 0.05) and area of TT (p < 0.05) were significantly larger in the RVN group compared with the RSG-IAC group. Conclusion Ears amenable to the RVN approach had a greater pDL and TT area. These anatomical measurements may have a role in surgical planning and the choice of approach for SVN.

Selective retromastoid vestibular neurectomy for intractable Ménière's disease: a technical note

BACKGROUND

Retrosigmoid vestibular neurectomy is considered to be the most effective and safe procedure to control intractable vertigo associated with Ménière's disease while preserving hearing. The surgical procedure of retrosigmoid vestibular neurectomy at the cerebellopontine angle has been well established. Here, we provide for otologic surgeons additional details about the procedure, with special attention to the anatomic features to emphasize our technique, which enables an adequate sectioning of the vestibular fibers on the cochlear nerve close to the overlapping zone containing large-caliber vestibular fibers and small-caliber cochlear fibers.

METHODS

We used the lateral decubitus position to enter the cerebellopontine angle. The cerebellum was gently retracted to expose the cerebellomedullary cistern, which was then opened to drain the cerebrospinal fluid for slacking of the cerebellum. The underlying lower cranial nerves IX, X, and XI were identified. The retractor was then moved upward to locate the internal acoustic meatus and the complexes VIII-VII. Adjacent to the internal auditory canal, a longitudinal incision, about 3 mm long and 0.5 mm away from the landmarks of arteriole or cochleovestibular cleavage plane, was made on the cochlear nerve. A surgical separation plane was bluntly created using a microdissector between the two components, and the vestibular nerve was sharply sectioned with microscissors.

RESULTS

We re-examined the patients' hearing status, word recognition (speech discrimination) skill, functional levels, and frequency of vertiginous episodes 1 month and at all 6-month intervals after the surgery. At 2 years after surgery, vertigo was completely controlled, indicating a 100% cure rate.

CONCLUSION

Sectioning of vestibular fibers was performed along the cochleovestibular cleavage landmark on the cochlear nerve where the overlapping zone was located, allowing for a safe and adequate vestibular neurectomy, while most of the cochlear fibers were spared.

Middle fossa vestibular neurectomy for refractory vertigo: less is more

OBJECTIVE

This study aimed to evaluate outcomes of the middle fossa (MF) superior vestibular neurectomy in unilateral Ménière's disease.

PATIENTS AND METHODS

Case series with preoperative and postoperative analysis of the 1995 American Academy of Otolaryngology hearing stage and vertigo class, gait instability, and results of vestibular-evoked myogenic potentials (VEMP).

RESULTS

Four out of the 5 patients had total vertigo control (class A) and 1 had near total control (class B) by the last visit (mean follow-up, 23.6 months). There were no changes in hearing thresholds and hearing stage. Four patients had resolution of their gait instability by 2 months after surgery. Postoperative VEMP responses were preserved in all 3 patients with positive VEMP preoperatively.

CONCLUSION

This is the first report of the anatomical and functional preservation of the inferior vestibular nerve in vestibular neurectomy for the treatment of refractory vertigo in unilateral Ménière's disease, with VEMP testing before and after vestibular neurectomy. The modified technique limits the surgical dissection and may help avoid complications such as postoperative hearing loss and persistent gait instability. This approach is indicated when other more conservative measures have failed, and patient selection is paramount to avoid long-term complications.

The keyhole retrosigmoid approach to the cerebello-pontine angle: indications, technical modifications, and results

OBJECTIVES

Establish the versatility and usefulness of the keyhole retrosigmoid approach to the cerebello-pontine angle (CPA) in various pathologies.

DESIGN

Prospective clinical study.

SETTING

Tertiary referral university hospital.

METHODS

One hundred twenty-one patients with various pathologies of the CPA underwent the relevant investigations and were operated upon by the retrosigmoid microendoscopic approach. The technical modifications and progression of our technique are described.

RESULTS

This group consisted of 121 patients (103 men and 28 women). The pathologies included were 60 acoustic neuromas, 28 vestibular neurectomies, nine meningiomas, and four arachnoid cysts. For nonmass lesions, no additional facial nerve injury or deterioration of hearing occurred. Total excision of mass lesions was achieved in 94.5% of cases. Facial nerve integrity was preserved in 92.3% of cases with mass lesions and permanent facial paralysis occurred in 8.3%. There were no mortalities, and the most frequent complication was a delayed cerebrospinal fluid leak from the site of the wound (15%), which was managed conservatively in all cases.

CONCLUSIONS

The keyhole retrosigmoid approach is a versatile one. It can be used to deal with different pathologies through a unified access, and with the increasing exclusive use of endoscopes, a truly minimally invasive surgery can be achieved.