The Short- and Long-Term Outcome of Intratympanic Steroid Therapy as a Salvage Treatment for Acute Low-Tone Sensorineural Hearing Loss without Episodes of Vertigo

Prognosis of Acute Low-Tone Hearing Loss Without Vertigo: A Scoping Review

OBJECTIVE

Despite its relatively high prevalence, our understanding of the natural clinical course of acute low-tone hearing loss (ALHL) without vertigo remains incomplete. The purpose of this study is to summarize the findings of studies that evaluated recovery from hearing loss (HL), recurrence and/or fluctuation of HL, and progression to Meniere's Disease (MD) of patients presenting with ALHL without vertigo.

METHODS

A scoping review of the English literature was performed. On May 14, 2020 and July 6, 2022, MEDLINE, Embase, and Scopus were searched to identify articles related to the prognosis of ALHL. To be included, articles had to present outcomes that were clearly distinguishable for patients with ALHL without vertigo. Two reviewers evaluated articles for inclusion and extracted data. Disagreements were adjudicated by a third reviewer.

RESULTS

Forty-one studies were included. There was extensive heterogeneity between studies in regard to defining ALHL, treatment methods, and time of follow-up. Most of the cohorts (39 out of 40) reported partial or complete recovery of hearing in the majority (>50%) of patients, although reports of recurrence were relatively common. Progression to MD was infrequently reported. Shorter time from onset of symptoms to treatment predicted better hearing outcomes in 6 of 8 studies.

CONCLUSION

The literature suggests that although the majority of patients with ALHL experience hearing improvement, recurrence and/or fluctuation are common, and progression to MD occurs in a minority of patients. Additional trials utilizing standardized inclusion and outcome criteria are needed to determine the ideal treatment for ALHL.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:2457-2469, 2023.

Development and Characteristics of Hearing Loss With the Progression of Endolymphatic Hydrops

OBJECTIVES

This study aims to explore how patients' hearing loss developed with the progression of endolymphatic hydrops and the characteristics of hearing loss at different stages.

MATERIALS AND METHODS

We collected 73 patients with definite or possible unilateral Meniere's disease or sudden hearing loss who underwent magnetic resonance imaging after intravenous contrast agent injection. There were 25 cases of isolated cochlear hydrops, 24 cases of isolated vestibular hydrops, and 24 cases of cochlear and vestibular hydrops. Primary outcome analyses included their evaluation of endolymphatic hydrops and hearing thresholds at low and high frequencies.

RESULTS

The overall hearing threshold of patients with vestibular and cochlear hydrops was significantly higher than that of patients with isolated cochlear hydrops and patients with isolated vestibular hydrops. There was a significant correlation between low-frequency hearing loss and cochlear hydrops, and the low-frequency hearing threshold was proportional to the grade of cochlear hydrops. At low frequency, the hearing threshold of patients with isolated vestibular hydrops was lower than that of patients with isolated cochlear hydrops and patients with both cochlear and vestibular hydrops. The audiogram configurations of patients with isolated cochlear hydrops consist largely of flat type and up-sloping type. The audiogram configurations of patients with isolated vestibular hydrops and patients with both cochlear and vestibular hydrops are mainly flat type and down-sloping type.

CONCLUSIONS

Patients present with low-frequency hearing loss in the early stage of endolymphatic hydrops. When the hydrops involves the whole cochlea and vestibule, the patients' hearing is impaired at both low and high frequencies.

Intratympanic corticosteroid as salvage therapy in treatment of idiopathic sudden sensorineural hearing loss: A systematic review and meta-analysis

Background

The standard treatment of idiopathic sudden sensorineural hearing loss (ISSNHL) constitutes of systemic oral corticosteroid. Although oral corticosteroid might revert the acute deafness, some patients with ISSNHL display a more treatment refractory course. For these patients, corticosteroid installed directly into the middle ear has become a more frequent treatment, due to the potential benefits of a high, local concentration compared to a systemic administration. As such, for patients being refractory to standard treatment, intratympanic injection of a high dosage of corticosteroid as salvage therapy may be beneficial.

Objectives

To evaluate the efficacy of intratympanic corticosteroid (ITC) as a salvage treatment of ISSNHL.

Methods

A systematic literature search was performed in relevant databases. Both randomized trials and observational studies were considered for inclusion. The risk of bias was evaluated using the Cochrane risk of bias tool (randomized trials) or ROBINS-I tool (observational studies). Meta-analysis was performed to investigate the improvement of PTA (dB) and number of patients displaying recovery following salvage ITC injections. Occurrence of serious side effects was investigated. Finally, the certainty of the evidence was evaluated using the GRADE approach.

Results

Eleven relevant studies were identified (4 randomized trials and 7 observational studies). Both observational and randomized trials showed that salvage ITC significantly increased the number of patients displaying recovery. No serious adverse events were identified in any of the included studies. The certainty of evidence ranged from moderate to very low, due to risk of bias, imprecision, and heterogeneity.

Conclusion

Collectively, our findings indicate that salvage ITC treatment may be a beneficial and safe treatment for patients with sudden hearing loss, who otherwise are refractory to standard treatment approaches. However, the evidence level indicates need for a cautious interpretation of especially the magnitude of effect and thus the extrapolation on how much the individual may improve from this treatment. Furthermore, it remains to be investigated whether treatment outcomes may vary across different patient groups presenting with ISSNHL. This potential variation in treatment response should be kept in mind, when counselling the patient.

Trial registration number

The protocol is registered in PROSPERO. Registration number: CRD42019130586.

Magnetic resonance imaging of the endolymphatic space in patients with acute low-tone sensorineural hearing loss

OBJECTIVE

The aim of this study was to measure the volume of the endolymphatic space (ELS) and to investigate prognosis in patients with acute low-tone sensorineural hearing loss (ALHL).

METHODS

A total of 61 ALHL patients participated; 47 were definite while 14 were probable ALHL cases. The definite ALHL patients were classified into three groups: A, "Cure"; B, "No cure"; and C, "Recurrence." Also, nine patients for whom diagnosis changed from ALHL to cochlear Meniere's disease (cMD) without vertigo (ALHL-cMD group). Images of the inner ear fluid space, positive perilymph, and positive endolymph were acquired using a 3T magnetic resonance scanner. Three-dimensional (3D) images were semi-automatically reconstructed using anatomical and tissue information to fuse the 3D images of the inner ear fluid space with the 3D ELS images.

RESULTS

Patients in the no cure group showed a significantly higher ELS/total fluid space (TFS) volume ratio in the affected cochlear region than the patients of the other groups. Additionally, the affected vestibular ELS/TFS volume ratio in the cure group was significantly lower than that in the recurrence group. There were significantly higher cochlear and vestibular ELS/TFS ratios in ALHL-cMD patients than in control subjects.

CONCLUSIONS

These results indicate that the cochlear ELS/TFS volume ratio should be considered when investigating the extent of recovery, while the extended ELS in the vestibule should be considered when investigating cases of recurrence. Thus, our study suggests that the severe extended ELS appeared likely to change to cMD and that the prognostic determination of ALHL is possible.

Comorbid Symptoms Occurring During Acute Low-Tone Hearing Loss (AHLH) as Potential Predictors of Menière's Disease

Acute low-tone sensorineural hearing loss (ALHL) is a type of idiopathic sudden sensorineural hearing loss. ALHL is rarely a solitary condition but rather co-occurs with vertigo and tinnitus, being an element of contemporary diagnostic criteria for Menière's disease (MD). The goal of our present study was to determine the value of ALHL for the early diagnosis of MD in patients presenting in the emergency room with ALHL as a main complaint. The files of 106 patients with ALHL who were admitted to the emergency room over the period of 7 years and 104 patients with acute high- tone sensorineural hearing loss (AHHL) from the same period were included in this retrospective study. Forty ALHL patients presented with recurrent episode of hearing loss and 66 remaining patients presented with ALHL for the first time. Of the latter group, 25 patients gave consent for the follow-up. First, we analyzed the difference in the occurrence of tinnitus and vertigo between the ALHL and AHHL groups. In patients with ALHL, the incidence of vertigo with tinnitus and the number of recurrent episodes were statistically higher than in patients with AHHL. Next, we focused on the ALHL follow-up group (25 patients). In that group, two patients had all MD symptoms at presentation, 18 had ALHL and tinnitus and five ALHL only. Of 18 patients with ALHL and tinnitus at admission, five developed vertigo and thus the triad of Menière's disease. None of the five patients with AHLH as a sole symptom developed MD during the follow-up time but four of them have developed tinnitus. Patients with recurrent ALHL had significantly higher incidence of MD than the patients with first episode. We conclude that some patients who present with ALHL and concomitant tinnitus or have recurrent episodes of ALHL are more likely to develop Menière's disease than these patients, who present with ALHL as a sole symptom. Nonetheless, we recommend otological follow-up for all patients presenting with ALHL.

Idiopathic sudden sensorineural hearing loss and acute low-tone sensorineural hearing loss: a comparison of the results of a nationwide epidemiological survey in Japan

OBJECTIVES

The aim of this study was to investigate the differences between idiopathic sudden sensorineural hearing loss (SSNHL), and acute low-tone sensorineural hearing loss (ALHL) using the results of a nationwide survey database in Japan and to analyze the variables associated with their clinical features and the severity of hearing impairment, treatment, and prognosis.

METHODS

Participants were patients registered between April 2014 and March 2016 in a multicenter epidemiological survey database involving 30 university hospitals and medical centers across Japan. Statistical analysis was performed to clarify the factors associated with their clinical characteristics and the severity of hearing impairment, treatment, and prognosis.

RESULTS

Idiopathic SSNHL and ALHL differed significantly in terms of male-to-female ratio, age distribution, and time from onset to start of treatment. The treatment methods and hearing prognosis also differed markedly between the two diseases. A majority (92%) of idiopathic SSNHL patients were administered some type of corticosteroid, while half of the ALHL patients received corticosteroids and a diuretic agent.

CONCLUSION

The results suggested that idiopathic SSNHL and ALHL belonged to different categories of inner ear disease.