Current concepts in the diagnosis and treatment of sudden sensorineural hearing loss

Butylphthalide enhances recovery from sudden deafness

OBJECTIVES

Cochlear microcirculation disturbance caused by vasculopathy is a common cause of sudden deafness (SD). Reactive oxygen species (ROS) plays an important role in cochlear injury during ischemia-reperfusion. Butylphthalide can improve microcirculation, reduce ROS formation and inhibit apoptosis. The aim of this study was to investigate the therapeutic effect of butylphthalide on patients with SD.

PATIENTS AND METHODS

The hearing gains from 32 ears treated with butylphthalide were compared with that of 32 ears treated with non-butylphthalide. Butylphthalide capsules was administrated orally on an empty stomach for 10 continuous days. There were no significant differences in audiological and clinical data between butylphthalide and non-butylphthalide groups.

RESULTS

The hearing gain of butylphthalide group at 500, 1000, 2000, and 4000 Hz was significantly higher than that of non-butylphthalide group correspondingly (P<0.01). And, the hearing gain at PTA (pure-tone average of 500, 1000, 2000, and 4000 Hz) in butylphthalide group was significantly higher than that of non-butylphthalide group (P<0.01).

CONCLUSION

The recovery of hearing in butylphthalide group was significantly better than that of non-butylphthalide group. It is confirmed that butylphthalide has a definite therapeutic effect on SD.

Corticosteroids versus vestibular rehabilitation in long-term outcomes in vestibular neuritis

BACKGROUND:

The management strategy for functional recovery after vestibular neuritis (VN) has not yet been established. Therapeutic choices involve corticosteroids, vestibular rehabilitation therapy (VRT) and the combination of corticosteroids with VRT.

OBJECTIVE:

The present study aimed to compare the efficacy of corticosteroids, vestibular rehabilitation, and combination of them in terms of subjective and objective improvement in patients with VN.

METHODS:

A prospective randomized study was conducted on 60 patients with acute vestibular neuritis within 3 days after symptom onset. The patients were divided into three groups; steroid group treated with corticosteroids (n = 20), VRT group (n = 20) managed with vestibular rehabilitation exercises and combination group (n = 20) received combined (corticosteroids and vestibular exercises). Groups were compared by caloric lateralization, vestibular myogenic potential amplitude asymmetry and Dizziness Handicap Inventory scores, both at presentation and up to 12 months.

RESULTS:

The study found no statistically significant difference between the three groups of the study at the end of the follow up period.

CONCLUSION:

Corticosteroids and VRT seem to be equivalently effective in patients with VN. The study proposes that corticosteroids may accelerate the recovery of VN, with no more beneficial role in the long-term prognosis of the disease.

Does Herpes Virus Reactivation Affect Prognosis in Idiopathic Sudden Sensorineural Hearing Loss?

Objectives

Several etiologies have been proposed to underlie idiopathic sudden sensorineural hearing loss (ISSNHL), including viral infection, vascular disturbance, and immune-mediated mechanisms. However, none of these mechanisms are conclusive. Should ISSNHL be caused by reactivation of a viral infection, antiviral treatment would be an important option. Thus, in this study, we reported the prognosis according to serologic test results of herpes viruses in patients with ISSNHL. We also evaluated treatment response with acyclovir and corticosteroids versus corticosteroids alone in herpes simplex virus (HSV) seropositive ISSNHL patients.

Methods

We compared hematologic examinations and the results of audiometry testing in 232 patients with ISSNHL. Statistical analyses for initial hearing impairment, progression of hearing impairment, recovery of hearing loss, and laboratory results were performed in all patients. All statistical analyses were performed using SPSS software.

Results

The 232 ISSNHL patients were divided into two subgroups according to HSV immunoglobulin M (IgM) serologic results (seropositive or seronegative). When the seropositive group was compared to the seronegative group, age, gender, body mass index (BMI), white blood cell, absolute neutrophil count, absolute monocyte count, and platelet count were not significantly different. Initial hearing level, final recovery hearing level, and recovery time were also not significantly different between the two groups (P>0.05). Though there were no significant differences in age, gender, BMI, or viral HSV IgM titer, the two groups had similar initial hearing level, final recovery hearing level, and recovery time. The difference in hearing threshold before and after treatment was larger (18.7±37.1) in the group receiving antiviral medication than in the corticosteroids group (11.0±44.5), but this difference was not significant (P=0.619).

Conclusion

There was no significant difference of prognosis between the patients with and without reactivation of HSV. In addition, there seems to be no benefit for the treatment of acyclovir combined with the corticosteroids in the patients with ISSNHL.

Evaluation of Super-High-Dose Steroid Therapy for Sudden Sensorineural Hearing Loss

OBJECTIVE: To determine the efficacy of a high-dose steroid regimen for patients with sudden sensorineural hearing loss (SSNHL) and to evaluate the relationship between outcome and initial steroid dose.

STUDY DESIGN AND SETTING: We conducted a retrospective study of 112 patients presenting to Saitama Medical Center. Patients received tapering courses of hydrocortisone (HC) with an initial dose of either 1200 mg or 600 mg.

RESULTS: More than 87% of patients had recovery of hearing. When hearing stabilized, there were no significant differences between the 1200 mg and 600 mg groups in terms of hearing outcome ( P > 0.05). However, at completion of treatment, the 1200 mg group exhibited significantly superior complete recovery rate and improvement rate ( P < 0.05).

CONCLUSION: Application of our treatment protocol of a tapered course of 1200 mg HC significantly and rapidly improves recovery outcomes in patients of SSNHL.

EBM rating: C-4

High fibrinogen in peripheral blood correlates with poorer hearing recovery in idiopathic sudden sensorineural hearing loss

Objectives

We used hearing tests and peripheral blood sample analyses to characterize the pathology of idiopathic sudden sensorineural hearing loss (ISSNHL) and to identify possible prognostic factors for predicting recovery of hearing loss.

Study Design

A retrospective, multicenter trial was conducted.

Methods

Two hundred three patients examined within 7 days after the onset of ISSNHL received prednisone with lipo-prostaglandin E1. Pure-tone auditory tests were performed before and after treatment with these drugs. Blood tests were performed on blood samples collected during the patients’ initial visit to our clinic.

Results

In all patients, elevated white blood cell (WBC) counts, fasting blood sugar levels, HgbA1c, and erythrocyte sedimentation rate (ESR) significantly correlated with high hearing threshold measurements obtained on the initial visit. High fibrinogen levels, WBC counts, ESR, and low concentrations of fibrinogen degradation products (FDP) were associated with lower hearing recovery rates. Additionally, different audiogram shapes correlated with different blood test factors, indicating that different pathologies were involved.

Conclusions

High fibrinogen levels measured within seven days after ISSNHL onset correlated with poorer hearing recovery. This may be a consequence of ischemia or infections in the inner ear. The high WBC counts also observed may therefore reflect an immune response to inner ear damage induced by ischemic changes or infections. Our data indicate that therapeutic strategies should be selected based on the timing of initial treatment relative to ISSNHL onset.

Radix astragali injection enhances recovery from sudden deafness

OBJECTIVES

An acute interruption of the blood supply to the inner ear is one of the most likely causative factors for sudden deafness (SD). Reactive oxygen species (ROS) have been suggested to be important mediators of the tissue injury during cochlear ischemia and reperfusion. Radix astragali (RA) is natural antioxidant. The aim of this study was to investigate the efficacy of RA in patients with SD.

PATIENTS AND METHODS

We compared the hearing gains from hearing impairment in 46 ears treated with RA with 46 ears treated with non-RA. RA was given intravenously daily for 10 days. There were no significant differences in clinical or audiological data between RA and non-RA groups.

RESULTS

The hearing gain at 250, 500, 1000, 2000, and 4000 Hz in RA group was much higher than that of non-RA group correspondingly (P < .01). Also, the hearing gain at PTA (pure-tone average of 250, 500, 1000, 2000, and 4000 Hz) in RA group was significantly higher than that of non-RA group (P < .01).

CONCLUSION

The recovery of hearing was significantly better after treatment of RA than non-treatment of RA. RA can be valuable concurrent therapy for patients with SD.

Steroid combination therapy and detoxification enzyme gene polymorphisms in sudden sensorineural hearing loss patients

OBJECTIVE

The purpose of this study was to evaluate the relations among the combined therapy with steroid and the detoxification enzyme gene polymorphisms in patients with sudden sensorineural hearing loss (SSNHL). The pathogenetic mechanism of inner ear dysfunction could involve an increase in lipid peroxidation and a decrease in cellular antioxidant defense. Glutathione S-transferases (GSTs) and cytochrome P450 (CYP) belong to a system of detoxification and antioxidant enzymes that have been demonstrated in the inner ear.

STUDY DESIGN

A prospective study in patients with SSNHL.

PATIENTS AND METHODS

All 441 subjects were genotyped for GSTM1, GSTT1, and CYP1A1 polymorphisms. The polymorphisms were analyzed by polymerase chain reaction amplification, restriction enzyme digestion, and deoxyribonucleic acid fragment separation by electrophoresis.

RESULTS

No significant difference was observed between SSNHL patients and controls in 3 polymorphisms. However, the prevalence of the partial recovery group in patients with the CC genotype of CYP1A1 (22%) was higher than that in the complete recovery (7.4%) or no recovery group (12.5%) for the subjects classified according to modified Siegel's criteria but were not statistically significant.

CONCLUSION

This is the first approach to analyze gene polymorphism and efficacy of clinical treatment of patients with SSNHL, although the observations do not confirm the effect of the GSTM1/T1 and CYP1A1 genotypes as a risk factor for SSNHL.

Role of nitric oxide on purinergic signalling in the cochlea

In the inner ear, there is considerable evidence that extracellular adenosine 5'-triphosphate (ATP) plays an important role in auditory neurotransmission as a neurotransmitter or a neuromodulator, although the potential role of adenosine signalling in the modulation of auditory neurotransmission has also been reported. The activation of ligand-gated ionotropic P2X receptors and G protein-coupled metabotropic P2Y receptors has been reported to induce an increase of intracellular Ca(2+) concentration ([Ca(2+)](i)) in inner hair cells (IHCs), outer hair cells (OHCs), spiral ganglion neurons (SGNs), and supporting cells in the cochlea. ATP may participate in auditory neurotransmission by modulating [Ca(2+)](i) in the cochlear cells. Recent studies showed that extracellular ATP induced nitric oxide (NO) production in IHCs, OHCs, and SGNs, which affects the ATP-induced Ca(2+) response via the NO-cGMP-PKG pathway in those cells by a feedback mechanism. A cross-talk between NO and ATP may therefore exist in the auditory signal transduction. In the present article, I review the role of NO on the ATP-induced Ca(2+) signalling in IHCs and OHCs. I also consider the possible role of NO in the ATP-induced Ca(2+) signalling in SGNs and supporting cells.

Systematic review of the evidence for the etiology of adult sudden sensorineural hearing loss

OBJECTIVES/HYPOTHESIS

To determine the evidence for different etiologies of sudden sensorineural hearing loss (SSNHL) identified by clinical diagnostic tests in the adult population.

STUDY DESIGN

Systematic literature review.

METHODS

Review of MEDLINE (1950-October 2009), EMBASE (1980-October 2009), and EBM Review databases in addition to manual reference search of identified papers. Randomized controlled trials, prospective cohort studies, and retrospective reviews of consecutive patients in which a clear definition of SSNHL was stated and data from consecutive patients were reported with respect to etiology of hearing loss. Three researchers independently extracted data regarding patient demographic information, diagnostic tests employed, and the identified presumed etiologies. Discrepancies were resolved by mutual consensus.

RESULTS

: Twenty-three articles met the inclusion criteria. The first group of papers searched for different etiologies among patients with SSNHL. Multiple etiologies were identified, including viral infection, vascular impairment, autoimmune disease, inner ear pathology, and central nervous system anomalies. The diagnosis for the majority of patients remained idiopathic. The second group of papers evaluated SSNHL patients with specific diagnostic tests such as autoimmune markers, hemostatic parameters, and diagnostic imaging.

CONCLUSIONS

The suspected etiologies for patients suffering sudden sensorineural hearing loss included idiopathic (71.0%), infectious disease (12.8%), otologic disease (4.7%), trauma (4.2%), vascular or hematologic (2.8%), neoplastic (2.3%), and other causes (2.2%). Establishment of a direct causal link between SSNHL and these etiologies remains elusive. Diagnostic imaging is a useful method for identification of temporal bone or intracranial pathology that can present with SSNHL as a primary symptom.

Corticosteroids in the treatment of vestibular neuritis: a systematic review and meta-analysis

OBJECTIVE

To systematically review and meta-analyze the results of all randomized controlled trials comparing corticosteroids with placebo for the treatment of patients with vestibular neuritis.

DATA SOURCES

An electronic search was performed in MEDLINE, EMBASE, Cochrane Library, and CENTRAL databases, and then extensive hand-searching was performed for the identification of relevant studies. No time and language limitations were applied.

STUDY SELECTION

Prospective randomized controlled trials comparing corticosteroids with placebo for the treatment of patients with vestibular neuritis.

DATA EXTRACTION

Odds ratios (ORs), weighted mean differences (WMD), 95% confidence intervals (CIs), and tests for heterogeneity were reported.

DATA SYNTHESIS

Four studies were eventually identified and systematically reviewed. Meta-analysis was feasible for 3 studies. Regarding the recovery of clinical symptoms, the proportion of patients with clinical recovery at 1 month after the initiation of therapy did not differ significantly between the corticosteroids and placebo groups (OR, 1.45; 95% CI, 0.26-8.01; p = 0.67). The proportion of patients with caloric complete recovery was significantly different between the corticosteroids and placebo groups both at 1 (OR, 12.64; 95% CI, 2.6-61.52; p = 0.002; heterogeneity, p = 0.53; fixed effects model) and 12 months (OR, 3.35; 95% CI, 1.45-7.76; p = 0.005; heterogeneity, p = 0.03; random effects model) after the initiation of therapy. The caloric extent of canal paresis at 12 months after the initiation of therapy seemed to differ significantly between patients who received corticosteroids and those who received placebo (WMD, -12.15; 95% CI, -19.85 to -4.46; p < 0.05; heterogeneity, p < 0.05; random effects model).

CONCLUSION

The present systematic review and meta-analysis, based on the currently available evidence, suggests that corticosteroids improve only the caloric extent and recovery of canal paresis of patients with vestibular neuritis. At present, clinical recovery does not seem be better in patients receiving corticosteroids.

Remote tentorium meningioma causing sudden sensorineural deafness

BACKGROUND

Sudden sensorineural deafness is a well-known symptom mostly of unknown etiology.

CASE DESCRIPTION

A case of sudden sensorineural deafness is reported to be caused by a small, remote, ipsilateral tentorial meningioma not compressing the vestibulocochlear nerve or auditory tract. Surgical resection of the meningioma immediately restored the patient's hearing.

CONCLUSION

The authors hypothesize that the sudden sensorineural deafness resulted from a growing meningioma inducing a neurovascular compression of the vestibulocochlear nerve, the vertebral artery already being in close relationship with the vestibulocochlear nerve in the premorbid phase. Resection of the meningioma allows for an autodecompression of this vascular conflict resulting in hearing restoration.

Hyperbaric oxygen and steroid therapy for idiopathic sudden sensorineural hearing loss

In our controlled retrospective analysis of medical records in tertiary care academic medical center, we aimed to investigate the therapeutic effects of hyperbaric oxygen (HBO) therapy combined with steroid administration for idiopathic sudden sensorineural hearing loss (ISSNHL) in comparison with that of steroid administration alone. Our subjects were 130 consecutive inpatients with ISSNHL (hearing levels >/=40 dB; time from the onset of hearing loss to the start of treatment </=30 days). Sixty-seven patients underwent HBO plus steroid therapy (HBO group), and 63 were given steroids alone (steroid group). Hearing recovery was evaluated by grade assessment and by the improvement in hearing compared to that in the unaffected contralateral ear. The cure rate and hearing improvement rate were not statistically different between the two groups; however, the recovery rate was significantly higher in the HBO group than in the steroid group (59.7% vs. 39.7%; P < 0.05). With regard to patients with initial hearing levels of >/=80 dB, the hearing improvement rate was significantly higher in the HBO group than in the steroid group (51.1 +/- 7.0% vs. 27.1 +/- 7.8%; P < 0.05), while in patients whose initial hearing levels were <80 dB, hearing outcomes were not statistically different between the two groups. In both the HBO and steroid groups, patients with initial hearing levels of <80 dB showed a better hearing improvement rate than those with initial hearing levels of >/=80 dB. In conclusion HBO therapy shows a significant additional effect in combination with steroid therapy for ISSNHL, particularly in patients with severe hearing loss.

Impact of prognostic factors on recovery from sudden hearing loss

Objective:

To define the impact of patient-related and audiovestibular parameters on the prognosis of sudden hearing loss.

Methods:

Eighty-three patients were included in this retrospective study. All were treated medically. We recorded the patients' demographic parameters, systemic diseases, time elapsed between onset of sudden hearing loss and initiation of treatment, tinnitus, vestibular symptoms, type of initial audiogram, pure tone averages and speech discrimination scores. For all patients, audiological measurements were performed on initial admission and at the completion of treatment on the 10th day.

Results:

There was no correlation between the hearing gain and recovery rate scores and patients' gender or age (p>0.05). However, a correlation was found between gender and relative hearing gain. Vertigo was not correlated with hearing gain and recovery rate scores (p<0.05). However, relative hearing gain correlated negatively with the presence of vertigo (−r=0.05, 81 degrees of freedom,p=0.043). Patients with <40 dB hearing loss on admission showed a better relative hearing gain (r=0.55, 81 degrees of freedom,p=0.03). Relative hearing gain correlated positively with better pre-treatment speech discrimination scores (r=0.82, 81 degrees of freedom,p=0.009) and negatively with poorer pre-treatment pure tone averages (−r=0.082, 81 degrees of freedom,p=0.009). There was no correlation between the scores for hearing gain, relative hearing gain and recovery rate and: systemic diseases (p>0.05); time elapsed between onset of sudden hearing loss and initiation of treatment (p>0.05); type of audiogram on initial admission (p>0.05), except for midfrequency type of audiogram; and tinnitus (p>0.05).

Conclusions:

The outcome of sudden hearing loss was unaffected by systemic disease, tinnitus or type of audiogram (except for midfrequency type). The following were poor prognostic factors in the outcome of sudden hearing loss: female gender, presence of vertigo, initiation of treatment more than seven days after onset of hearing loss, and >40 dB hearing loss on admission.

Combined treatment of sudden sensorineural hearing loss with steroid, dextran and piracetam: experience with 68 cases

The purpose of this study was to evaluate the effectiveness of our combined treatment regimen and to clarify the possible prognostic factors in sudden sensorineural hearing loss (SSNHL). In a retrospective chart review, the charts of 68 patients who matched the inclusion criteria of this study were evaluated. All patients were treated with a standard regimen including prednisone, dextran and piracetam between January 1998 and December 2001. Initial (at the beginning of therapy) and final (3 weeks after the beginning of therapy) audiograms were compared with respect to hearing improvement. Possible prognostic factors were also evaluated. Overall hearing improvement was determined as 54.4%. Sex was the only determined prognostic factor in this study. Females had a better prognosis. Our treatment regimen had no superiority to the reported spontaneous hearing recovery. Females seem to have a better prognosis.

Steroid effects on vestibular compensation in human

Vestibular neuritis (VN) rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. We experienced 36 patients with VN treated at our hospital, including cases in our previous preliminary report. To elucidate effects of steroid therapy both on the recovery of peripheral function and on the adaptation of central vestibular compensation, we examined caloric test and several questionnaires with two randomly divided groups, 18 steroid-treated and 18 nonsteroid-treated patients, over two years after the onset. These examinations revealed that steroid-treated patients had a tendency of better canal improvements (13/18, 72%) than nonsteroid-treated ones (10/18, 55.6%). However, there was no significant difference between these two groups. In cases with persistent canal paresis, steroid-treated patients (n = 5) reduced handicaps in their everyday life due to the dizziness induced by head and/or body movements and the disturbance of their mood, more effectively than those with nonsteroid therapy (n = 8). These findings suggest that steroid therapy with VN could be effective on not only vestibular periphery but central vestibular system, to restore the balance.

Effect of prostaglandin E1 on idiopathic sudden sensorineural hearing loss: a double-blinded clinical study

OBJECTIVE AND STUDY DESIGN

The authors conducted a prospective, randomized, double-blinded clinical trial for the purpose of elucidating the effects of prostaglandin E1 (PGE1) on idiopathic sudden sensorineural hearing loss.

SETTING AND PATIENTS

With the approval of the institute ethics committee, a total of 57 consecutive patients with diagnoses of idiopathic sudden sensorineural hearing loss were included in the study. The patients in the PGE1 group received continuous infusion containing 60 microg PGE1 and 100 mg hydrocortisone for 7 days, and the patients in the placebo group were treated with continuous infusion containing an inactive placebo and 100 mg hydrocortisone.

RESULTS

No significant differences were observed in the improvements of pure-tone average and subjective symptoms between the PGE1 and the placebo groups. However, the hearing improvement at high frequencies (4 kHz and 8 kHz) was significantly higher in the PGE1 group than in the placebo group, especially in the patients with severe tinnitus.

CONCLUSIONS

These results failed to prove a beneficial effect of PGE1 in the treatment of idiopathic sudden sensorineural hearing loss. Further studies will be needed to clarify the pharmacologic actions of PGE1 in the cochlea.

Infection screening in sudden and progressive idiopathic sensorineural hearing loss: a retrospective study of 182 cases

OBJECTIVE

To evaluate a systematic infectious screening program for patients who present with sudden or progressive sensorineural hearing loss (SHL) of unknown cause (negative history and clinical examination).

METHOD

Retrospective study of 182 patients with idiopathic SHL. One hundred six patients presented with sudden SHL, and 76 presented with progressive SHL. Serologies for herpes simplex and varicella-zoster viruses (immunoglobulin M and immunoglobulin G titers), Lyme disease (enzyme-linked immunosorbent assay), syphilis (fluorescent treponemal antibody absorption or microhemagglutination-Treponema pallidum test) and human immunodeficiency virus were performed.

RESULTS

The serologies were negative in 179 patients. Two patients had positive serologies for Lyme disease and another tested positive for syphilis. Both cases of suspected Lyme disease were later excluded by Western blot analysis and lumbar puncture (two false-positives). The patient with serologic syphilis was diagnosed as having latent syphilis after neurosyphilis was excluded.

CONCLUSION

The infection screening was positive in only 1 (0.6%) of 182 patients: the patient who was diagnosed with latent syphilis. On the basis of these results and taking into account the cost of systematic screening, we propose that serologic tests be limited to patients with suspect histories or symptomatologies, except for patients with a diagnosis of syphilis.