Quantitative assessment of vestibular otopathology in otosclerosis: A temporal bone study

Brazilian Society of Otology task force - Otosclerosis: evaluation and treatment

OBJECTIVES

To review and provide evidence-based recommendations for the diagnosis and treatment of otosclerosis.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on otosclerosis were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: 1) Diagnosis - audiologic and radiologic; 2) Treatment - hearing AIDS, pharmacological therapy, stapes surgery, and implantable devices - bone-anchored devices, active middle ear implants, and Cochlear Implants (CI).

CONCLUSIONS

The pathophysiology of otosclerosis has not yet been fully elucidated, but environmental factors and unidentified genes are likely to play a significant role in it. Women with otosclerosis are not at increased risk of worsening clinical condition due to the use of contraceptives or during pregnancy. Drug treatment has shown little benefit. If the patient does not want to undergo stapedotomy, the use of hearing aids is well indicated. Implantable systems should be indicated only in rare cases, and the CI should be indicated in cases of profound deafness.

Vertigo Associated with Otosclerosis and Stapes Surgery-A Narrative Review

Otosclerosis is a pathological condition affecting the temporal bone, and is characterized by remodelling of the labyrinthine bone tissue through a dynamic process of osteolysis and osteogenesis. This condition progressively leads to hearing loss, tinnitus, and vertigo. Stapedotomy, a surgical procedure involving the removal of the stapes superstructure and its replacement with a prosthesis, is the treatment of choice to improve hearing in individuals with otosclerosis. However, vestibular dysfunction is a significant complication associated with this procedure, which can occur intraoperatively or postoperatively, ranging from the immediate postoperative period to weeks, months, or even years after surgery. This paper aims to provide a comprehensive review of the most important causes of vertigo associated with otosclerosis and stapes surgery with the goal of minimizing the incidence of this complication. Understanding the underlying factors contributing to vertigo in this context is crucial for the prevention and effective management of vertigo in patients undergoing stapedotomy.

Retrospective Study of 157 Patients with Otosclerosis to Evaluate Association Between Carhart Notch on the Preoperative Bone-Conduction Audiogram and Postoperative Hearing and Balance Evaluated by the Vestibular Disorders Activities of Daily Living Scale

BACKGROUND A Carhart notch in the pure tone audiogram can be an indicator of stapes fixation in otosclerosis. This retrospective study of 157 patients with otosclerosis aimed to evaluate the association between the presence of a Carhart notch on the preoperative bone-conduction audiogram and postoperative hearing and balance evaluated by the Vestibular Disorders Activities of Daily Living scale. MATERIAL AND METHODS Patients with suspected otosclerosis based on medical history and audiometric tests were considered. The analysis included 157 consecutive patients who underwent surgery in the years 2016 to 2019, in whom the diagnosis of otosclerosis was confirmed during surgery. Carhart notch was defined as an impairment in the bone conduction threshold of ≥7.5 dB for 2000 Hz frequencies above the mean thresholds at higher and lower adjacent frequencies. The Vestibular Disorders Activities of Daily Living subjective scale was used in the preoperative period and 4 and 12 months after surgery. RESULTS The preoperative presence of Carhart notch and progressive sensorineural hearing loss were statistically significantly correlated with more common onset of tinnitus and then dizziness (P=0.006). Preoperative vertigo was observed in patients who had Carhart notch observed in the preoperative audiometric test. This vertigo more commonly coexisted with profound sensorineural hearing loss and minor or no improvement in average values of bone conduction after surgery (P=0.002). CONCLUSIONS Preoperative Carhart notch on audiogram and the severity of sensorineural hearing loss were associated with tinnitus and vertigo. However, preoperative Carhart notch was not associated with persistent postoperative tinnitus in patients with cochlear otosclerosis.

Comprehensive vestibular evaluation in patients with Otosclerosis: a case control study

Aim

Otosclerosis is one of the common otologic diseases. The mechanism and the probable site of vestibular involvement are not yet fully understood. The present study aimed to perform a comprehensive vestibular evaluation in patients with otosclerosis, compared to the cases without otosclerosis.

Materials and methods

patients underwent a comprehensive cochleovestibular evaluation, including audiometry, ocular and cervical vestibular evoked myogenic potential (o-VEMP and c-VEMP), video head impulse (vHIT) and caloric tests. The results were compared with those obtained from the non-otosclerosis control group.

Results

A total of 61 individuals were included in the study who were divided into two groups of the case (50.82%) and control (49.18%). The results showed that there was a significant difference in the mean vHIT gain between the case and control groups (P < 0.05). However, the mean gain was still within the normal range. Besides, the patients with otosclerosis had significant bilateral or unilateral weaknesses according to caloric test results. Moreover, their o-VEMP and c-VEMP results were significantly abnormal as well (P < 0.05).

Conclusion

Based on the results of the present study, the vestibular system even in asymptomatic cases, is affected by otosclerosis. Furthermore, it seems that the otolithic system has a higher chance of involvement, compared to the semicircular canals.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-022-03147-5.

Positive and negative post stapedotomy effects on cervical VEMP recordings; a STROBE analysis

AIMS

The primary goal of the present study was to compare the pre- and post-stapedotomy elicitation and waveform characteristics of both air- and bone-conduction (AC-, BC-) cervical vestibular evoked myogenic potentials (cVEMPs) through an individualized approach. A possible association between audiological characteristics, such as AC- and BC- pure tone audiometry thresholds and air-bone gap and the production of cVEMPs before and after stapedotomy was also investigated.

MATERIAL AND METHODS

Twenty-five ears were subjected to full audiological evaluation as well as AC- and BC-cVEMPs pre- and post-stapedotomy. Four subgroups were studied; consistently present/absent, post-operatively disappeared and restored cVEMPs.

RESULTS

Post-stapedotomy changes in cVEMP elicitability did not reach significance for either AC-cVEMP (OR=5.41, 95% CI 0.88-33.36, P=0.06) or BC-cVEMP (OR=2.40, 95% CI 0.42-13.60, P=0.3). Normal or abnormal AC-cVEMPs were equally subject to post-operative changes (OR=1.95, 95% CI 0.32-12.01, P=0.5), as were BC-cVEMPs (OR=3.75, 95% CI 0.66-21.25, P=0.1). Neither the audiological characteristics nor the surgical outcome, in terms of ABG results, were relevant to the presence or absence of AC- and BC-cVEMPs before or after stapedotomy.

CONCLUSIONS

The presumed changes brought to the sacculus by stapedotomy are minor and beyond the diagnostic abilities of either AC-cVEMPs or BC-cVEMPs, both in terms of cVEMPs elicitability and waveform characteristics. In individual cases, however, which may deserve further investigation, cVEMPs may reappear or disappear after stapedotomy probably following minor changes toward a lower or higher vestibular system resistance for pressure and sound transmission.

Surgical treatment of otosclerosis leading to changes in postural control and quality of life

OBJECTIVE

Evaluating postural function in patients with otosclerosis by assessing otoneurological function and balance-related quality of life before and 6 weeks after surgical treatment. Correlations between and clinical features were investigated.

METHODS

Thirty-three patients affected by otosclerosis underwent otoneurological examination, video Head Impulse Test (vHIT), and static posturography before and after stapedotomy. Quality of life and dizziness-related handicap were screened by means of validated questionnaires. Correlation analysis was performed in order to discover possible relations with audiological pre- and postoperative parameters.

RESULTS

A significant improvement in posturographic parameters was found. Correlation analysis yielded a negative correlation between preoperative bone conduction auditory threshold and both vHIT scores and postural performance improvement, evaluated by spectral analysis. Moreover, a positive correlation was also found between improvements in posturographic scores and quality-of-life questionnaires.

CONCLUSION

The study results demonstrated an improvement in postural function and self-reported measures in a cohort of patients with otosclerosis 6 weeks after stapedotomy. The inverse correlation with preoperative auditory levels may reflect lesser chance for balance restoration in cases with worse sensorineural function. Possible implications for daily activities and overall quality of life were suggested by improved self-report questionnaire results.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2448-2454, 2020.

Use of Multiple Ultrasonographic Parameters in Confirmation of Carpal Tunnel Syndrome

OBJECTIVES

Ultrasonography (US) of the median nerve has been increasingly studied and used for confirmation of carpal tunnel syndrome (CTS). However, a consensus on the choice of parameters to be evaluated is still not established. The aim of this diagnostic accuracy study was to assess the diagnostic value of multiple parameters individually, as well as in different combinations of variable complexity, and to find an optimal approach for US-based confirmation of a CTS diagnosis.

METHODS

All participants completed clinical and electrophysiologic evaluations, and their hands were scanned with a 5-13-MHz linear US transducer. Eighty-six patients with CTS (135 symptomatic hands) and 50 control participants (93 asymptomatic hands) were analyzed. The median nerve was recorded transversely at the forearm, at the carpal tunnel inlet, in the mid tunnel, and at the carpal tunnel outlet. For determining the parameters' diagnostic value, sensitivities, specificities, and area under the curve (AUC) values were calculated.

RESULTS

The inlet cross-sectional area, inlet circumference, and outlet cross-sectional area of the median nerve had the highest AUCs (0.962, 0.920, and 0.913, respectively), sensitivities (87.4%, 80.0%, and 74.1%), and specificities (94.6%, 91.4%, and 92.5%) among single-measurement parameters. An analysis of 2-level parameters (wrist-to-forearm-ratio, inlet-to-outlet-ratio, outlet-to-forearm-ratio, and inlet-outlet mean) yielded the highest AUC (0.974) for the mean cross-sectional area of the median nerve [(inlet + outlet cross-sectional area)/2], with high sensitivity (93.5%) and specificity (91.1%). A compound regression-based index yielded a marginally higher AUC (0.989) than the previously mentioned parameters.

CONCLUSIONS

Results of the study show that the mean cross-sectional area and inlet cross-sectional area may be valid and easy-to-acquire parameters for routine clinical use in confirming CTS.

Does Otosclerosis Affect Dark and Transitional Cells in the Human Vestibular Labyrinth?

HYPOTHESIS

The density of vestibular dark cells (DCs) and vestibular transitional cells (TCs) can be quantitatively decreased in human temporal bones with otosclerosis.

BACKGROUND

Previous reports have shown that otosclerosis can lead to vestibular symptoms.

METHODS

We examined 61 human temporal bone specimens from 52 deceased donors with otosclerosis group-with and without endosteal involvement (EI), and with and without endolymphatic hydrops (EH)-versus 25 specimens from 18 age-matched controls. Using light microscopy, we evaluated the nonsensory epithelium of the lateral semicircular canal (LSC) and posterior semicircular canal (PSC) of the human vestibular labyrinth, focusing on the density of DCs and TCs.

RESULTS

In both the LSC and the PSC, as compared with the control group, the mean density of DCs significantly decreased in the EI (+) group, in the EI (+) and EH (+) subgroup, and in the EI (+) and EH (-) subgroup (p < 0.05). In addition, we found a significant difference in the mean density of DCs between the EI (+) group and the EI (-) group in the LSC and in the PSC (p < 0.05). But we found no significant difference in the mean density of TCs in any of the otosclerosis groups or subgroups as compared with the control group (p > 0.05).

CONCLUSION

We found a decrease in the density of DCs associated with EI in human temporal bone specimens with otosclerosis, regardless of the presence of EH. This decrease might cause damage in ion and water transportation, leading to vestibular symptoms.