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.

Evaluation of the transmastoid plugging approach for superior semicircular canal dehiscences: a retrospective series of 30 ears.

PURPOSE: The classical surgical approach for superior semicircular canal dehiscences (SSCD) is via the extradural middle cranial fossa. This pathway is used to resurface or to plug the SSC. In this paper, we present long-term data on an alternative route: the transmastoid pathway. The predictive factors for a successful surgery are equally presented in this paper. METHODS: Thirty reports of patients operated between September 2007 to January 2020 were analysed. SSCD was confirmed by the association of concordant complaints, audiometric data, cervical vestibular evoked myogenic potentials (cVEMP) responses and computerized tomography findings. Before and after surgery, the following factors were analysed: auditory and vestibular subjective symptoms, Tullio phenomenon, pure-tone audiometry thresholds for air and bone conduction, air-bone gap, cVEMP threshold, and computerized tomography data, for instance the size of the dehiscence. RESULTS: The follow-up is 21 months on average. The transmastoid approach significantly improves all symptoms (although there were less probing results for the vestibular symptoms). Objectively, we can observe, a closure of the audiometric air-bone gap on the low frequencies and an improvement in the cVEMP. The only correlation that was identified was between the preoperative cVEMP results and the postoperative air conduction. CONCLUSIONS: The originality of this study is the long postoperative follow-up. It allowed us to evaluate the symptoms in the long term and to determine a predictive factor of postoperative complication, which has not yet been described until today.The transmastoid plugging technique is safe and effective. Additional long-term data with a larger cohort are needed to confirm our results and correlation studies.

Comparison between 3D SPACE FLAIR and 3D TSE FLAIR in Menière's disease.

PURPOSE: Heavily T2-weighted 3D FLAIR (hT2w-3D-FLAIR) sequence with constant flip angle (CFA) has been reported as being more sensitive to low concentrations of gadolinium (Gd) enabling endolymphatic hydrops (EH) visualization. The purpose of this study was to compare signal-to-noise (SNR) ratio, detection rate of EH, and increased perilymphatic enhancement (PE) as well as diagnostic accuracy in diagnosing definite Menière's disease (MD), using 3D-SPACE FLAIR versus conventional 3D-TSE FLAIR. METHODS: This retrospective study included 29 definite MD patients who underwent a 4-h delayed intravenous (IV) Gd-enhanced 3D-TSE FLAIR and 3D-SPACE FLAIR MRI between February 2019 and February 2020. MR images were qualitatively and quantitatively analyzed twice by 2 experienced head and neck radiologists. Qualitative assessment included grading of cochlear and vestibular EH and visual comparison of PE. Quantitative assessment of PE was performed by placing a region of interest (ROI) and ratio calculation in the basal turn of the cochlea and the brainstem. RESULTS: The intra- and inter-reader reliability for grading of EH and PE was excellent (0.7 < kappa < 0.9) for 3D-SPACE FLAIR and exceeded the values for 3D-TSE FLAIR (0.5 < kappa < 0.9) The combination of EH and visual assessment of PE has the highest diagnostic accuracy in diagnosing definite MD on 3D-SPACE FLAIR with a sensitivity of 0.91 and a specificity of 0.98 resulting in a sensitivity raise of 6% compared to 3D-TSE FLAIR. CONCLUSION: Four-hour delayed IV Gd-enhanced 3D-SPACE FLAIR sequence has a higher sensitivity and reproducibility than 3D-TSE FLAIR for the visualization of EH and increased PE in definite MD patients.

The relationship between cochleovestibular function tests and endolymphatic hydrops grading on MRI in patients with Menière's disease.

PURPOSE: In this retrospective study the relationship between cochleovestibular function and a magnetic resonance imaging (MRI-) based classification system of endolymphatic hydrops was investigated. METHODS: Seventy-eight patients with unilateral definite Menière's disease who underwent MRI were included. The parameters of Pure Tone Audiometry (PTA), caloric irrigation test, cervical vestibular evoked myogenic potentials, and video Head Impulse Test were compared between the grades of endolymphatic hydrops (EH) and perilymphatic enhancement (PE) on MRI. RESULTS: The low-frequency PTA was significantly different between cochlear EH grades I and II (p = 0.036; Grade I: mean (Standard Deviation, SD) = 51 decibel Hearing Level (dB HL) (18 dB HL); Grade II: mean (SD) = 60 dB HL (16 dB HL)), and vestibular EH grades 0 and III (p = 0.018; Grade 0: mean (SD) = 43 dB HL (21 dB HL); Grade III: mean = 60 dB HL (10 dB HL)). The ipsilateral caloric sum of ears with vestibular EH grade I (n = 6) was increased with regards to vestibular EH grades 0 (p = 0.001), II (p < 0.001), and III (p < 0.001) (Grade 0: mean (SD) = 24°/s (15°/s); Grade I: mean (SD) = 47°/s (11°/s); Grade II: mean (SD) = 21°/s (13°/s); Grade III: mean (SD) = 16°/s (8°/s)). CONCLUSION: According to these results we can conclude that only the highest grades of cochlear and vestibular EH seem to be associated with decreased cochleovestibular functioning.

The value of four stage vestibular hydrops grading and asymmetric perilymphatic enhancement in the diagnosis of Menière's disease on MRI.

PURPOSE: There is still a clinical-radiologic discrepancy in patients with Menière's disease (MD). Therefore, the purpose of this study was to investigate the reliability of current MRI endolymphatic hydrops (EH) criteria according to Baráth in a larger study population and the clinical utility of new imaging signs such as a supplementary fourth low-grade vestibular EH and the degree of perilymphatic enhancement (PE) in patients with Menière's disease (MD). METHODS: This retrospective study included 148 patients with probable or definite MD according to the 2015 American Academy of Otolaryngology, Head and Neck Surgery criteria who underwent a 4-h delayed intravenous Gd-enhanced 3D-FLAIR MRI between January 2015 and December 2016. Vestibular EH, vestibular PE, cochlear EH, and cochlear PE were reviewed twice by three experienced readers. Cohen's Kappa and multivariate logistic regression were used for analysis. RESULTS: The intra- and inter-reader reliability for the grading of vestibular-cochlear EH and PE was excellent (0.7 < kappa < 0.9). The two most distinctive characteristics to identify MD are cochlear PE and vestibular EH which combined gave a sensitivity and specificity of 79.5 and 93.6%. By addition of a lower grade vestibular EH, the sensitivity improved to 84.6% without losing specificity (92.3%). Cochlear EH nor vestibular PE showed added-value. CONCLUSIONS: MRI using vestibular-cochlear EH and PE grading system is a reliable technique. A four-stage vestibular EH grading system in combination with cochlear PE assessment gives the best diagnostic accuracy to detect MD.

The Neural Correlates of Chronic Symptoms of Vertigo Proneness in Humans.

Vestibular signals are of significant importance for variable functions including gaze stabilization, spatial perception, navigation, cognition, and bodily self-consciousness. The vestibular network governs functions that might be impaired in patients affected with vestibular dysfunction. It is currently unclear how different brain regions/networks process vestibular information and integrate the information into a unified spatial percept related to somatosensory awareness and whether people with recurrent balance complaints have a neural signature as a trait affecting their development of chronic symptoms of vertigo. Pivotal evidence points to a vestibular-related brain network in humans that is widely distributed in nature. By using resting state source localized electroencephalography in non-vertiginous state, electrophysiological changes in activity and functional connectivity of 23 patients with balance complaints where chronic symptoms of vertigo and dizziness are among the most common reported complaints are analyzed and compared to healthy subjects. The analyses showed increased alpha2 activity within the posterior cingulate cortex and the precuneues/cuneus and reduced beta3 and gamma activity within the pregenual and subgenual anterior cingulate cortex for the subjects with balance complaints. These electrophysiological variations were correlated with reported chronic symptoms of vertigo intensity. A region of interest analysis found reduced functional connectivity for gamma activity within the vestibular cortex, precuneus, frontal eye field, intra-parietal sulcus, orbitofrontal cortex, and the dorsal anterior cingulate cortex. In addition, there was a positive correlation between chronic symptoms of vertigo intensity and increased alpha-gamma nesting in the left frontal eye field. When compared to healthy subjects, there is evidence of electrophysiological changes in the brain of patients with balance complaints even outside chronic symptoms of vertigo episodes. This suggests that these patients have a neural signature or trait that makes them prone to developing chronic balance problems.

Outcome evaluation of the dizziness handicap inventory in an outpatient vestibular clinic.

BACKGROUND: The DHI is a widely used questionnaire for the evaluation of the self-reported disability in patients with dizziness and balance problems. OBJECTIVE: To investigate the relationship between the DHI scores and demographic, symptomatic and diagnostic parameters. METHODS: Retrospective study in 568 patients with balance problems. RESULTS: We observed a total of 61.3% of patients with moderate (DHI total score between 30 and 59) to severe (DHI total score between 60 and 100) disability.Patients with long-standing complaints (lasting longer than 3 months) experience their self-reported disability to a greater extent than patients with new onset pathology (illness duration of one month and less). Moreover, patients suffering from continuous complaints have a larger DHI score than patients with shorter symptom duration. The first effect (new onset vs. long-standing pathology) is primarily caused by emotional factors, the latter effect (symptom duration) is attributable to functional and physical factors, not to emotional aspects. Patients with daily and weekly complaints have larger DHI scores than patients who reported only one episode. Female patients reported larger DHI scores than males. We found no effect of age, diagnostic group (no diagnosis, episodic, acute or chronic vestibular syndrome) or reported symptoms on the DHI scores. CONCLUSIONS: The information retrieved from the DHI questionnaire is complementary to the information obtained from clinical investigation and diagnostic tests and therefore is an essential tool in a vestibular clinic.

Ocular vestibular-evoked myogenic potentials (oVEMP) to skull taps in normal and dehiscent ears: mechanisms and markers of superior canal dehiscence.

The site of stimulus delivery modulates the waveforms of cervical- and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP) to skull taps in healthy controls. We examine the influence of stimulus location on the oVEMP waveforms of 18 patients (24 ears) with superior canal dehiscence (SCD) and compare these with the results of 16 healthy control subjects (32 ears). oVEMPs were recorded in response to taps delivered with a triggered tendon-hammer and a hand-held minishaker at three midline locations; the hairline (Fz), vertex (Cz) and occiput (Oz). In controls, Fz stimulation evoked a consistent oVEMP waveform with a negative peak (n1) at 9.5 ± 0.5 ms. In SCD, stimulation at Fz produced large oVEMP waveforms with delayed n1 peaks (tendon-hammer = 13.2 ± 1.0 ms and minitap = 11.5 ± 1.1 ms). Vertex taps produced diverse low-amplitude waveforms in controls with n1 peaks at 15.5 ± 1.2 and 13.2 ± 1.3 ms for tendon-hammer taps and minitaps, respectively; in SCD, they produced large amplitude oVEMP waveforms with n1 peaks at 12.9 ± 0.8 ms (tendon-hammer) and 12.1 ± 0.5 ms (minitap). Occiput stimulation evoked oVEMPs with similar n1 latencies in both groups (tendon-hammer = 11.3 ± 1.3 and 10.7 ± 0.8; minitap = 10.3 ± 0.9 and 11.1 ± 0.4 for control and SCD ears, respectively). Compared to reflex amplitudes, n1 peak latencies to Fz taps provided clearer separation between SCD and control ears. The distinctly different effects of Fz and vertex taps on the oVEMP waveforms may represent an additional non-osseous mechanism of stimulus transmission in SCD. For skull taps at Fz, a prolonged n1 latency is an indicator of SCD.

No effects of anti-motion sickness drugs on vestibular evoked myogenic potentials outcome parameters.

OBJECTIVE: To investigate the effects of meclizine (50 mg), baclofen (10 mg), cinnarizine (20 mg) + dimenhydrinate (40 mg), and promethazine (25 mg) + dextro-amphetamine (5 mg) on the parameters of the vestibular evoked myogenic potential (VEMP) test. STUDY DESIGN: Double-blind placebo-controlled prospective randomized trial. SETTING: University hospital. SUBJECTS: Twenty-four (first block: baclofen versus placebo) and 20 healthy male subjects (second block: meclizine, cinnarizine + dimenhydrinate and promethazine + dextro-amphetamine versus placebo). INTERVENTIONS: VEMP test. MAIN OUTCOME MEASURES: Threshold, p13 and n23 latencies, p13-n23 latency difference, p13-n23 peak-to-peak amplitude, mean rectified voltage of the sternocleidomastoid muscle contraction and the corrected amplitude. RESULTS: There were no clinically significant pharmacologic effects on the VEMP outcome parameters. However, there was a statistically significant left-right asymmetry after intake of the combination promethazine + d-amphetamine for the parameters p13 and latency difference. CONCLUSION: The absence of clinically significant effects can be explained by the predominant presence of the target receptors for the applied drugs in the medial vestibular nucleus, which receives the lowest grade of saccular projections. It also can be hypothesized that the VEMP methodology and techniques in general do not allow determining pharmacologic effects in a healthy group of subjects because of a too small discriminative power. The left-right asymmetry can be explained by a depressive action of the drugs on the central compensation mechanisms. Because there were no significant differences between the VEMP parameters obtained after intake of the placebos of both blocks, we concluded that there were no training effects.

Influence of tonic and burst transcranial magnetic stimulation characteristics on acute inhibition of subjective tinnitus.

OBJECTIVE: Transcranial magnetic stimulation (TMS) is already broadly used in different areas of neuroscience research. In the last years, special attention was drawn to TMS in tinnitus. The aim of our study is to investigate the stimulation characteristics of TMS in tinnitus patients, in particular the effect of tonic and burst stimulation of the superior temporal lobe. STUDY DESIGN: Prospective sham-controlled study. SETTING: Tertiary referral center. PATIENTS: Fifty tinnitus patients were included in the study. Thirty-one patients had pure-tone tinnitus, and 19 patients had noise-like tinnitus. STUDY DESIGN: Transcranial magnetic stimulation was performed in 1 session of 200 pulses at different frequencies. Stimuli were delivered to the auditory cortex region contralateral to the tinnitus side. Tonic and burst stimulations were delivered at different frequencies. Patients were asked to rate the acute tinnitus reduction after TMS on a visual analog scale. MAIN OUTCOME MEASURE: Acutely perceived tinnitus reduction immediately after TMS, scored by the patient on a visual analogue scale ranging from 0 to 100%. RESULTS: Tinnitus reduction increased when stimulation intensity was higher relative to the patient's motor threshold. Nevertheless, this stimulation intensity was shown only to account for 10% of this increased tinnitus reduction, meaning that up to 90% of this effect should be ascribed to other factors than stimulation intensity alone. Different reactions on TMS were found in bilateral tinnitus patients compared with unilateral tinnitus patients. CONCLUSION: Several parameters determine the amount of tinnitus reduction after TMS. An increased stimulation intensity relative to the patient's motor threshold only accounts for 10% of this effect. Our data also suggest different pathophysiologic mechanisms for unilateral and bilateral tinnitus.

Auditory manifestations of superficial hemosiderosis of the central nervous system.

Superficial hemosiderosis of the central nervous system (SH-CNS) is a relatively rare condition caused by chronic or repeated subarachnoid bleeding. The aim of this article was to present hearing disorders related to SH-CNS, and to describe results of magnetic resonance imaging (MRI) to confirm the diagnosis. We performed a retrospective case review at a tertiary referral center. Clinical presentation, auditory manifestations and MRI findings of two patients with SH-CNS are reported. The two patients experienced bilateral sensorineural hearing loss (SNHL) that progressively worsened. MRI revealed typical aspects of SH-CNS on T2-weighted images. Progressive bilateral SNHL is the most common manifestation of SH-CNS. The otolaryngologist should be aware of this disease that can be easily diagnosed with MRI.

Congenital transsphenoidal meningocele: case report and review of the literature.

Intrasphenoidal meningoencephalocele is a rare clinical entity. Its origin can be congenital, traumatic, tumoral, or spontaneous. Presenting as cerebrospinal fluid fistula with rhinorrhea, the diagnosis and treatment of this uncommon disease is a real challenge for the otorhinolaryngologist. We report a case of sphenoidal meningocele treated using an endoscopic procedure and review the literature regarding its congenital origin.

Non-traumatic myositis ossificans in the paraspinal muscles.

Myositis ossificans circumscripta (MOC) is a benign condition of heterotopic bone formation that remains difficult to distinguish from soft-tissue and bone malignancies. We describe an unusual case of non-traumatic MOC in the cervical paraspinal muscle. The diagnosis could only be established after surgery and histological examination. We present a review of the literature on this subject and discuss some related features (radiological and histological).

Aggressive pilomatrixoma of the infra-auricular area: a case report.

Although pilomatrixomas are well known among dermatologists and dermatopathologists, head and neck surgeons confronted with these lesions in the infra-auricular region do not consider this benign neoplasm in the differential diagnosis. Aggressive pilomatrixoma is a benign tumor of the hair matrix cells affecting mainly children. Histologically, the border between aggressive pilomatrixoma and pilomatrix carcinoma is still not clear. We report the case of a 15-year-old Turkish boy suffering from an aggressive pilomatrixoma of the infra-auricular region and review the literature about this unclear entity.