Intratympanic Steroid Treatment: A Review

Development of a drug delivering round window niche implant for cochlear pharmacotherapy

BACKGROUND

There exists an unfulfilled requirement for effective cochlear pharmacotherapy. Controlled local drug delivery could lead to effective bioavailability. The round window niche (RWN), a cavity in the middle ear, is connected to the cochlea via a membrane through which drug can diffuse. We are developing individualized drug-eluting RWN implants (RNIs). To test their effectiveness in guinea pigs, a commonly used model in cochlear pharmacology studies, it is first necessary to develop guinea pig RNIs (GP-RNI).

METHODS

Since guinea pigs do not have a RWN such as it is present in humans and to reduce the variables in in vivo studies, a one-size-fits-all GP-RNI model was designed using 12 data sets of Dunkin-Hartley guinea pigs. The model was 3D-printed using silicone. The accuracy and precision of printing, distribution of the sample ingredient dexamethasone (DEX), biocompatibility, bio-efficacy, implantability and drug release were tested in vitro. The GP-RNI efficacy was validated in cochlear implant-traumatized guinea pigs in vivo.

RESULTS

The 3D-printed GP-RNI was precise, accurate and fitted in all tested guinea pig RWNs. DEX was homogeneously included in the silicone. The GP-RNI containing 1% DEX was biocompatible, bio-effective and showed a two-phase and sustained DEX release in vitro, while it reduced fibrous tissue growth around the cochlear implant in vivo.

CONCLUSIONS

We developed a GP-RNI that can be used for precise inner ear drug delivery in guinea pigs, providing a reliable platform for testing the RNI's safety and efficacy, with potential implications for future clinical translation.

Finite-element modelling of interactions of needle with tympanic membrane and middle ear

The tympanic membrane (TM) is one of the most common routes to access the middle ear and inner ear for the treatment of hearing and balance pathologies. Since the TM is a soft thin biological tissue with small dimensions, using needles seems to be among the most practical interventional approaches. In this study, we proposed a finite-element (FE) analysis of needle-TM interactions that combines a 3D model of the TM and other main middle-ear structures in gerbil, and a 2D model of needle insertion into the TM based on the cohesive zone method (CZM). The TM was modelled using a 1st-order Ogden hyperelastic material and its properties were obtained by fitting to the experimental force-displacement plots of large deformation in the TM under needle indentation. The cohesive parameters were also acquired by calibrating the puncture force against the experimental data of needle insertion into the TM. These FE models were then used to obtain the deformation behaviour of the TM and other middle-ear structures due to the insertion force applied at different locations on the TM. Moreover, we investigated the effect of the TM thickness, the geometry of the needle (i.e., diameter and tip angle), and needle material on the insertion of needles into the TM. We also studied the penetration success of deformable needles.

Intratympanic Dexamethasone Role in Hearing Protection in Cancer Patients

Introduction The study aims to determine the role of intratympanic dexamethasone (ITD) on the hearing profile of patients with head and neck cancer post-chemoradiotherapy. Study design This study employs a prospective case-control design. Subjects and methods In total 834 patients were evaluated for eligibility. Seven hundred and eleven were excluded because they didn't meet the inclusion criteria. A hundred cases out of 123 were diagnosed with head and neck cancer for which the treatment protocol included cisplatin concurrent to radiotherapy recruited. Before each cisplatin treatment session, ITD was injected into one ear (experimental ear) while the other ear of the same patient served as the control. Pure-tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAE) test results of the baseline and follow-up examinations in the sixth and 12th weeks were compared within and between the study and control ears. Results For pure tone thresholds, significant hearing threshold change was noticed at 8 kHz in the experimental group at six weeks and at ≥ 6 kHz in the control group. At 12 weeks, high frequencies were significantly affected at ≥ 4 kHz in the control group. When the baseline was compared across the groups in the 12th week, for otoacoustic emissions, high frequencies showed a loss in the control group more compared to the experimental side (Wilcoxon signed-rank test). Conclusion ITD functions less effectively at higher frequencies because the basal turn of the cochlea is more susceptible to cisplatin ototoxicity. ITD might have potential in the reduction of cisplatin-induced hearing loss.

Intratympanic corticosteroids for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. Corticosteroids are sometimes administered directly into the middle ear to treat this condition (through the tympanic membrane). The underlying cause of Ménière's disease is unknown, as is the way in which this treatment may work. The efficacy of this intervention in preventing vertigo attacks, and their associated symptoms, is currently unclear.

OBJECTIVES

To evaluate the benefits and harms of intratympanic corticosteroids versus placebo or no treatment in people with Ménière's disease.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 14 September 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs in adults with a diagnosis of Ménière's disease comparing intratympanic corticosteroids with either placebo or no treatment. We excluded studies with follow-up of less than three months, or with a cross-over design (unless data from the first phase of the study could be identified).  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were: 1) improvement in vertigo (assessed as a dichotomous outcome - improved or not improved), 2) change in vertigo (assessed as a continuous outcome, with a score on a numerical scale) and 3) serious adverse events. Our secondary outcomes were: 4) disease-specific health-related quality of life, 5) change in hearing, 6) change in tinnitus and 7) other adverse effects (including tympanic membrane perforation). We considered outcomes reported at three time points: 3 to < 6 months, 6 to ≤ 12 months and > 12 months. We used GRADE to assess the certainty of evidence for each outcome.  MAIN RESULTS: We included 10 studies with a total of 952 participants. All studies used the corticosteroid dexamethasone, with doses ranging from approximately 2 mg to 12 mg.  Improvement in vertigo Intratympanic corticosteroids may make little or no difference to the number of people who report an improvement in their vertigo at 6 to ≤ 12 months follow-up (intratympanic corticosteroids 96.8%, placebo 96.6%, risk ratio (RR) 1.00, 95% confidence interval (CI) 0.92 to 1.10; 2 studies; 60 participants; low-certainty evidence) or at more than 12 months follow-up (intratympanic corticosteroids 100%, placebo 96.3%; RR 1.03, 95% CI 0.87 to 1.23; 2 studies; 58 participants; low-certainty evidence). However, we note the large improvement in the placebo group for these trials, which causes challenges in interpreting these results.  Change in vertigo Assessed with a global score One study (44 participants) assessed the change in vertigo at 3 to < 6 months using a global score, which considered the frequency, duration and severity of vertigo. This is a single, small study and the certainty of the evidence was very low. We are unable to draw meaningful conclusions from the numerical results. Assessed by frequency of vertigo Three studies (304 participants) assessed the change in frequency of vertigo episodes at 3 to < 6 months. Intratympanic corticosteroids may slightly reduce the frequency of vertigo episodes. The proportion of days affected by vertigo was 0.05 lower (absolute difference -5%) in those receiving intratympanic corticosteroids (95% CI -0.07 to -0.02; 3 studies; 472 participants; low-certainty evidence). This is equivalent to a difference of approximately 1.5 days fewer per month affected by vertigo in the corticosteroid group (with the control group having vertigo on approximately 2.5 to 3.5 days per month at the end of follow-up, and those receiving corticosteroids having vertigo on approximately 1 to 2 days per month). However, this result should be interpreted with caution - we are aware of unpublished data at this time point in which corticosteroids failed to show a benefit over placebo. One study also assessed the change in frequency of vertigo at 6 to ≤ 12 months and > 12 months follow-up. However, this is a single, small study and the certainty of the evidence was very low. Therefore, we are unable to draw meaningful conclusions from the numerical results. Serious adverse events Four studies reported this outcome. There may be little or no effect on the occurrence of serious adverse events with intratympanic corticosteroids, but the evidence is very uncertain (intratympanic corticosteroids 3.0%, placebo 4.4%; RR 0.64, 95% CI 0.22 to 1.85; 4 studies; 500 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

The evidence for intratympanic corticosteroids in the treatment of Ménière's disease is uncertain. There are relatively few published RCTs, which all consider the same type of corticosteroid (dexamethasone). We also have concerns about publication bias in this area, with the identification of two large RCTs that remain unpublished. The evidence comparing intratympanic corticosteroids to placebo or no treatment is therefore all low- or very low-certainty. This means that we have very low confidence that the effects reported are accurate estimates of the true effect of these interventions. Consensus on the appropriate outcomes to measure in studies of Ménière's disease is needed (i.e. a core outcome set) in order to guide future studies in this area, and enable meta-analysis of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits. Finally, we would also highlight the responsibility that trialists have to ensure results are available, regardless of the outcome of their study.

Efficacy of intratympanic or postauricular subperiosteal corticosteroid injection combined with systemic corticosteroid in the treatment of sudden sensorineural hearing loss: A prospective randomized study

Objectives

This study aimed to investigate the efficacy and safety of intratympanic or postauricular subperiosteal glucocorticoid injection combined with systemic glucocorticoid in the treatment of sudden sensorineural hearing loss (SSNHL).

Methods

This study is a prospective randomized controlled study. This study included unilateral SSNHL patients who were hospitalized in our department between January 2020 and June 2021. Patients were randomly divided into three groups (groups A, B, and C). Patients in group A were treated with an intratympanic corticosteroid injection combined with systemic corticosteroid treatment, and patients in group B received a postauricular corticosteroid injection combined with systemic corticosteroid treatment. Patients in group C (control group) were treated with systemic corticosteroid alone. The case number of groups A, B, and C was 311, 375, and 369, respectively.

Results

There was no significant difference in gender distribution, the proportion of left and right affected ears, and the average interval from onset to treatment among the three groups (P > 0.05). However, there were significant differences in their average age, distribution of audiogram type, and hearing loss levels among them (P < 0.01). Our study shows that there was no significant difference in average hearing threshold improvement before and after treatment in the three groups (P > 0.05). Regarding the complications, in group A, 33 patients (10.6%) had a transient vertigo attack during tympanic injection, which lasted for ~1-3 min. In group B, 20 patients (6.43%) complained of pain at the injection site, which disappeared after 1-3 days. No other complications occurred in all the other patients.

Conclusion

The addition of intratympanic or postauricular corticosteroid to systemic steroids did not result in a significant effect on hearing recovery in SSNHL. No obvious complications occur in SSNHL patients treated with intratympanic injection or postauricular injection of corticosteroid.

Clinical trial registration

[chictr.org.cn], registration number: ChiCTR2100048762.

Nanocarriers for Inner Ear Disease Therapy

Hearing loss is a common disease due to sensory loss caused by the diseases in the inner ear. The development of delivery systems for inner ear disease therapy is important to achieve high efficiency and reduce side effects. Currently, traditional drug delivery systems exhibit the potential to be used for inner ear disease therapy, but there are still some drawbacks. As nanotechnology is developing these years, one of the solutions is to develop nanoparticle-based delivery systems for inner ear disease therapy. Various nanoparticles, such as soft material and inorganic-based nanoparticles, have been designed, tested, and showed controlled delivery of drugs, improved targeting property to specific cells, and reduced systemic side effects. In this review, we summarized recent progress in nanocarriers for inner ear disease therapy. This review provides useful information on developing promising nanocarriers for the efficient treatment of inner ear diseases and for further clinical applications for inner ear disease therapy.

Effects of Glucocorticoids on the Inner Ear

Hypothesis: Recently, several lines of evidence have suggested that the inner ear is under hormonal control. It is likely that steroids have some influence on the inner ear. Background: Many clinicians have been empirically using steroids for the treatment of diseases associated with endolymphatic hydrops. The theoretical grounds for this are not clear, and there have been a number of debates on the effectiveness of steroid treatment. Furthermore, there are few reports on histological observations of the influences of steroids on the cochlea. Method: Fifteen guinea pigs (30 ears) were divided into three groups. In the control group, physiological saline solution was administered intra-peritoneally for 3 days. In two steroid groups, 40 mg/kg/day of hydrocortisone or 4 mg/kg/day of dexamethasone was administered intra-peritoneally for 3 days. Extension of Reissner's membrane and volume change of the scala media were checked 6 h after the last administration. The degree of Reissner's membrane extension and volumetric change of the scala media were quantitatively measured with the use of a video-digitizer. Results: We did not identify any distinct changes in the cochlea of the control group. In contrast, the extension of Reissner's membrane and endolymphatic hydrops were observed in the animals in the steroid groups. Statistical analysis revealed that Reissner's membrane extended significantly in the steroid groups, and that the volume of the scala media also increased significantly. Conclusion: This is the first report to investigate the effects of systemic administration of glucocorticoids on guineapig cochlea. The extension of Reissner's membrane and dilated endolymphatic space were evident in the steroid groups. However, the underlying mechanism of histological changes was not clear, marked care needs to be taken when administering steroids to patients with Meniere's disease whose histological feature is endolymphatic hydrops.

Dexamethasone eardrop with grommet placement vs intratympanic steroid injection for sudden sensorineural hearing loss: A randomized prospective clinical trial

OBJECTIVES

The purpose of this study was to compare different means of intratympanic steroid delivery in the treatment of idiopathic sudden sensorineural hearing loss.

DESIGN

Prospective, multicentered, randomized controlled trial.

SETTING AND PARTICIPANTS

Fifty-six patients who fulfilled the inclusion criteria for idiopathic sudden sensorineural hearing loss who failed or were contraindicated for oral steroids were included in this study. Patients were randomly divided into 2 groups according to delivery methods: group A received 4 sections of intratympanic dexamethasone injection and group B received grommet placement with dexamethasone delivery followed by 3 sections of dexamethasone ear drop application. Self-administered paper-based questionnaires were filled out to measure subjective pain scores, vertigo, anxiety, and overall satisfaction immediately after each procedure. Hearing threshold was measured with pure tone audiogram in the follow-up.

RESULTS

There was no statistical significance detected in hearing threshold improvement between both groups (P = 0.30). Grommet placement followed by dexamethasone eardrop application demonstrated a significant difference in shorter waiting time (24 min in grommet group vs 52 min in injection group; P < 0.01); and better overall satisfaction (1.6 in grommet group vs 2.5 in injection group; P < 0.05).

CONCLUSIONS

Grommet placement followed by dexamethasone eardrop application is a good alternative for a patient indicated for intratympanic steroid, with less administrative cost, shorter waiting time, and more satisfaction.

Clinical Practice Guideline: Ménière's Disease

OBJECTIVE

Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid (endolymph) volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Conventional imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many and typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies.

PURPOSE

The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

Long-Term Follow-Up of Intratympanic Methylprednisolone Versus Gentamicin in Patients With Unilateral Menière's Disease

OBJECTIVES

To determine whether long term (>48 months) symptomatic vertigo control is sustained in patients with Menière's disease from a previous comparative trial of intratympanic methylprednisolone versus gentamicin, and if the two treatments remain nonsignificantly different at long-term follow-up.

STUDY DESIGN

Mail survey recording vertigo frequency in the previous one and six months, further intratympanic treatment received, and validated symptom questionnaires.

SETTING

Outpatient hospital clinic setting.

PATIENTS

Adult patients with definite unilateral refractory Menière's disease, who previously received intratympanic treatment in a comparative trial.

INTERVENTION

A survey of trial participants who received intratympanic gentamicin (40 mg/mL) or methylprednisolone (62.5 mg/mL).

OUTCOME MEASURES

Primary: number of vertigo attacks in the 6 months prior to receiving this survey compared with the 6 months before the first trial injection. Secondary number of vertigo attacks over the previous 1 month; validated symptom questionnaire scores of tinnitus, dizziness, vertigo, aural fullness, and functional disability.

RESULTS

Forty six of the 60 original trial patients (77%) completed the survey, 24 from the gentamicin and 22 from the methylprednisolone group. Average follow-up was 70.8 months (standard deviation 17.0) from the first treatment injection. Vertigo attacks in the 6 months prior to receiving the current survey reduced by 95% compared to baseline in both drug groups (intention-to-treat analysis, both p < 0.001). No significant difference between drugs was found for the primary and secondary outcomes. Eight participants (methylprednisolone = 5 and gentamicin = 3) required further injections for relapse after completing the original trial.

CONCLUSION

Intratympanic methylprednisolone treatment provides effective long-lasting relief of vertigo, without the known inner-ear toxicity associated with gentamicin. There are no significant differences between the two treatments at long term follow-up.

Hearing Preservation and Speech Outcomes After Cochlear Implantation in Meniere's Disease

OBJECTIVES/HYPOTHESIS

To evaluate speech perception outcomes and hearing preservation after cochlear implantation in patients with Meniere's disease (MD).

STUDY DESIGN

Retrospective chart review.

METHODS

Fifty-one adult patients, accounting for a total of 63 implants, with MD treated at a tertiary care center were included in the study. Patients with unaided preoperative air-conduction thresholds ≤80 dB at 250 Hz were included in hearing preservation analyses. The primary outcome measure was Consonant-Nucleus-Consonant (CNC) score. Hearing preservation was assessed as follows: 1) maintenance of functional hearing, defined as a postoperative unaided air-conduction threshold ≤80 dB at 250 Hz and 2) low-frequency pure-tone average (LFPTA) shift.

RESULTS

Speech perception scores improved significantly postimplantation; specifically, the CNC mean score was 9% preoperatively and increased to 57% by 1 year postoperatively (P < .001). Eighteen ears were included in hearing preservation analysis; the mean preoperative LFPTA was 65 dB (standard deviation [SD] = 10). The mean postoperative LFPTA at activation was 93 dB (SD = 21), and at 1 year was 102 dB (SD = 11). Twenty-seven percent of patients achieved short-term functional hearing preservation, whereas the longer-term outcomes were less favorable (11%).

CONCLUSIONS

Speech perception scores improve after implantation in patients with MD. Hearing preservation is possible in patients with MD, albeit at lower rates than reported non-MD populations. Our data suggest that there can be degradation in acoustic hearing over time.

LEVEL OF EVIDENCE

4 Laryngoscope, 2019.

Developments in Bio-Inspired Nanomaterials for Therapeutic Delivery to Treat Hearing Loss

Sensorineural hearing loss affects millions of people worldwide and is a growing concern in the aging population. Treatment using aminoglycoside antibiotics for infection and exposure to loud sounds contribute to the degeneration of cochlear hair cells and spiral ganglion neurons. Cell loss impacts cochlear function and causes hearing loss in ∼ 15% of adult Americans (∼36 million). The number of individuals with hearing loss will likely grow with increasing lifespans. Current prosthesis such as hearing aids and cochlear implants can ameliorate hearing loss. However, hearing aids are ineffective if hair cells or spiral ganglion neurons are severely damaged, and cochlear implants are ineffective without properly functioning spiral ganglion neurons. As such, strategies that alleviate hearing loss by preventing degeneration or promoting cell replacement are urgently needed. Despite showing great promise from in vitro studies, the complexity and delicate nature of the inner ear poses a huge challenge for delivering therapeutics. To mitigate risks and complications associated with surgery, new technologies and methodologies have emerged for efficient delivery of therapeutics. We will focus on biomaterials that allow controlled and local drug delivery into the inner ear. The rapid development of microsurgical techniques in conjunction with novel bio- and nanomaterials for sustained drug delivery appears bright for hearing loss treatment.

Efficacy of 2 Different Intratympanic Steroid Regimen on Prevention of Cisplatin Ototoxicity: An Experimental Study

Ototoxicity is the general name of cochlear and vestibular organ injury resulting from encountering various therapeutic agents and chemical substances. Cisplatin is commonly used in the treatment of many cancers. In this study, the efficacy of intratympanic steroids was compared for preventing cisplatin ototoxicity. In this study, 32 (64 ears) rats were used by separating into 4 groups. Cisplatin was administered intraperitoneally to the first group (n = 8). Methylprednisolone and then cisplatin were administered intratympanically to the second group (n = 8). On the third group (n = 8), dexamethasone and then cisplatin were administered intratympanically. To the fourth group (n = 8), 0.9% NaCl and then cisplatin were given intratympanically. Otoacoustic emission (OAE) measurements and auditory brainstem responses (ABRs) tests were performed on all groups before and 72 hours after the procedure. Pretreatment of ABR-IV values were 4.29 ± 0.19 milliseconds in group 2 and 4.27 ± 0.16 milliseconds in group 3, whereas posttreatment ABR-IV values were 4.95 ± 0.35 milliseconds in group 2 and 4.65 ± 0.26 milliseconds in group 3. The ABR-IV values were measured significantly shorter in the rats given dexamethasone and methylprednisolone, according to control and cisplatin groups (P < .001). Pretreatment of ABR I-IV interval values were 2.98 ± 0.34 milliseconds and 3.03 ± 0.42 milliseconds in group 1 and group 4, respectively, and ABR I-IV interval values in group 1 and group 4 posttreatment were 3.49 ± 0.39 milliseconds and 3.5 ± 0.39 milliseconds in group 1 and group 4, respectively. Auditory brainstem responses I-IV interval was significantly longer in the cisplatin and control group than in the rats given dexamethasone and methylprednisolone (P < .001). After cisplatin treatment, OAE amplitudes decreased significantly in group 1 and group 4 for all frequencies, while OAE values were protected in methylprednisolone and dexamethasone group (P < .001). In conclusion, it has been shown that both agents have protective effects on cisplatin ototoxicity, with dexamethasone slightly more than methylprednisolone.

Intratympanic corticosteroids in Ménière's disease: A mini-review

This article reviews the effectiveness of intratympanic corticosteroids for vertigo control in Ménière's disease at 2-years follow-up according to the guidelines expressed by the American Academy of Otolaryngology-Head & Neck Surgery. Despite the increased use of intratympanic corticosteroids for vertigo control in Ménière's disease there is debate as to their effectiveness, particularly compared to gentamicin. Even so, after just a single course of injections, corticosteroids can reliably provide complete vertigo control (Class A) at 2-years in about 50% of cases as indicated in a recent double-blind randomized controlled clinical trial (Patel et al., 2016). But the effectiveness of intratympanic corticosteroids truly increases when treatment is provided 'as-needed', whereby complete vertigo control is established in up to 91% of cases. On the basis of available literature, there is good evidence to recommend the use of intratympanic steroid treatment for vertigo control in Ménière's disease, but patients must be monitored for non-response. The rationale for treating patients as-needed and the possible reasons for corticosteroid non-response are discussed.

The Protective Effect of Intratympanic Dexamethasone on Streptomycin Ototoxicity in Rats

The purpose of this experimental study was to investigate the protective role of intratympanically administered dexamethasone on the inner ears of rats that were exposed to streptomycin ototoxicity. Twenty-four adult Wistar albino rats were separated into 4 groups: Group 1 (only streptomycin), Group 2 (only intratympanic dexamethasone), Group 3 (streptomycin and intratympanic dexamethasone), and Group 4 (streptomycin and intratympanic saline). All rats were evaluated with distortion product otoacoustic emissions (DPOAE) tests before the start of treatment and on the day it ended. On the 45th day, after the final DPOAE tests, animals of all groups were sacrificed under general anesthesia. The differences between the amplitudes of DPOAE results were determined, and hearing results were statistically analyzed. Also, the cochleas of each rat were histopathologically evaluated under a light microscope with hematoxylin and eosin staining. In the intratympanic dexamethasone group it was observed that cochlear hair cells were mostly protected. No significant difference was seen between the DPOAE results before and after treatment (p > 0.05). On the other hand, loss was observed in the hearing functions and hair cells of the rats that received streptomycin and streptomycin plus intratympanic saline (p < 0.05). In the streptomycin plus intratympanic dexamethasone group, the cochlear hair cells were partially protected. A significant difference was observed when the DPOAE results (DP-grams) of the streptomycin plus intratypmanic dexamethasone group were compared to those of the streptomycin plus intratympanic saline group (p < 0.05). After the experimental study, ototoxic effects of the administration of streptomycin and intratympanic dexamethasone were observed on the rats’ cochlear hair cells. We conclude that intratympanic dexamethasone has protective effects against this cochlear damage in rats.

Comparative Analysis of the Combined Therapeutic Effects of Lipoprostaglandin E1 on Sudden Idiopathic Sensorineural Hearing Loss

Background and Objectives

Viral and vascular disorders are considered to be a major cause of idiopathic sudden sensorineural hearing loss (ISSNHL). Lipoprostaglandin E₁ (lipo-PGE₁) has vasodilating activity and has been used to treat ISSNHL. The purpose of this study was to determine the specific therapeutic effects of lipo-PGE₁ and compare them to other treatment modalities for ISSNHL.

Subjects and Methods

The study group had 1,052 patients diagnosed with ISSNHL. All were treated with steroid, carbogen inhalation, stellate ganglion block (SGB), or PGE₁. The CP group (steroid, carbogen inhalation, and PGE1 injection; 288 patients) was treated with lipo-PGE₁ and carbogen inhalation, the CS group (steroid, carbogen inhalation, and stellate ganglion block; 232 patients) with steroid, carbogen inhalation, and SGB, the C group (steroid and carbogen inhalation; 284 patients) with steroid and carbogen, and the control group (steroid only; 248 patients) with steroid only. Patients in the groups receiving lipo-PGE₁ received a continuous infusion of 10 µL lipo-PGE₁.

Results

The overall recovery rate after treatment was 52.2%, and recovery rates by group were 67.7% in the CP group, 54.3% in the CS group, 52.1% in the C group, and 32.2% in the control group. Therefore, the therapeutic results in groups treated with lipo-PGE₁ were better than results in other groups. The difference was statistically significant.

Conclusions

The study results suggested that the CP group received effective treatment modalities for ISSNHL. The combined therapy of lipo-PGE₁ with carbogen inhalation in patients with ISSNHL was more beneficial than other treatment modalities.

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

Microfabricated reciprocating micropump for intracochlear drug delivery with integrated drug/fluid storage and electronically controlled dosing

The anatomical and pharmacological inaccessibility of the inner ear is a major challenge in drug-based treatment of auditory disorders. This also makes pharmacokinetic characterization of new drugs with systemic delivery challenging, because efficacy is coupled with how efficiently a drug can reach its target. Direct delivery of drugs to cochlear fluids bypasses pharmacokinetic barriers and helps to minimize systemic toxicity, but anatomical barriers make administration of multiple doses difficult without an automated delivery system. Such a system may be required for hair-cell regeneration treatments, which will likely require timed delivery of several drugs. To address these challenges, we have developed a micropump for controlled, automated inner-ear drug delivery with the ultimate goal of producing a long-term implantable/wearable delivery system. The current pump is designed to be used with a head mount for guinea pigs in preclinical drug characterization experiments. In this system, we have addressed several microfluidic challenges, including maintaining controlled delivery at safe, low flow rates and delivering drug without increasing the volume of fluid in the cochlea. By integrating a drug reservoir and all fluidic components into the microfluidic structure of the pump, we have made the drug delivery system robust compared to previous systems that utilized separate, tubing-connected components. In this study, we characterized the pump's unique infuse-withdraw and on-demand dosing capabilities on the bench and in guinea pig animal models. For the animal experiments, we used DNQX, a glutamate receptor antagonist, as a physiological indicator of drug delivery. DNQX suppresses compound action potentials (CAPs), so we were able to infer the distribution and spreading of the DNQX over time by measuring the changes in CAPs in response to stimuli at several characteristic frequencies.

Microfabricated infuse-withdraw micropump component for an integrated inner-ear drug-delivery platform

One of the major challenges in treatment of auditory disorders is that many therapeutic compounds are toxic when delivered systemically. Local intracochlear delivery methods are becoming critical in emerging treatments and in drug discovery. Direct infusion via cochleostomy, in particular, is attractive from a pharmacokinetics standpoint, as there is potential for the kinetics of delivery to be well-controlled. Direct infusion is compatible with a large number of drug types, including large, complex molecules such as proteins and unstable molecules such as siRNA. In addition, hair-cell regeneration therapy will likely require long-term delivery of a timed series of agents. This presents unknown risks associated with increasing the volume of fluid within the cochlea and mechanical damage caused during delivery. There are three key requirements for an intracochlear drug delivery system: (1) a high degree of miniaturization (2) a method for pumping precise and small volumes of fluid into the cochlea in a highly controlled manner, and (3) a method for removing excess fluid from the limited cochlear fluid space. To that end, our group is developing a head-mounted microfluidics-based system for long-term intracochlear drug delivery. We utilize guinea pig animal models for development and demonstration of the device. Central to the system is an infuse-withdraw micropump component that, unlike previous micropump-based systems, has fully integrated drug and fluid storage compartments. Here we characterize the infuse-withdraw capabilities of our micropump, and show experimental results that demonstrate direct drug infusion via cochleostomy in animal models. We utilized DNQX, a glutamate receptor antagonist that suppresses CAPs, as a test drug. We monitored the frequency-dependent changes in auditory nerve CAPs during drug infusion, and observed CAP suppression consistent with the expected drug transport path based on the geometry and tonotopic organization of the cochlea.

Optimal management of Ménière's disease

Confusion in the nomenclature of Ménière's disease and lack of a standard definition of the disorder until 1995 has hampered accurate assessment of treatment efficacy since the presently defined disorder was first described in 1938. The lack of a widely accepted mechanism of the disease has also delayed the development of rational treatments. Past treatments have focused on relieving elevated pressures in the hydropic ear and more recently on treatment of underlying migraine. Present dietary methods of control include sodium restriction and migraine trigger elimination. Pharmacologic treatments include diuretics, migraine prophylactic medications, histamine analogs, and oral steroids. Surgical procedures include intratympanic steroid perfusion, shunts, and ablative procedures when conservative treatments fail. External pressure devices are also used. Evidence of efficacy is lacking for most interventions other than ablation. At our institution, Ménière's disease is treated as a cerebrovascular disorder. Control of risk factors for cerebrovascular ischemia is combined with treatment of pressure dysfunction in the hydropic ear. Screening for risk factors is performed at presentation. Migraine, dyslipidemia, obesity, diabetes, sleep apnea, hypertension, and atherosclerosis are among the major factors that often require medical management. Migraine prophylactic medications, magnesium supplementation, sodium restriction, migraine trigger elimination, diuretics, anticoagulants, and antihypertensives are among the treatments used initially. Steroids administered orally or intratympanically are used if control is not achieved medically, and ablation remains the definitive treatment in unilateral cases experiencing treatment failure.

Longitudinal results of intratympanic injection of budesonide for otitis media with effusion in children over 12 years and adults

OBJECTIVE

To assess the longitudinal curative effect and improvement of subjective symptoms by using intratympanic injection of Budesonide(BUD) for otitis media with effusion (OME) patients older than 12 years and adults.

STUDY DESIGN

A single-blind, randomized, parallel-controlled prospective study.

SETTING

Hospital, outpatient.

PATIENTS

Ninety patients (112 ears) who were diagnosed as having OME were recruited and then randomized to BUD, dexamethasone (DEX), and sodium chloride (NS) groups, the latter two served as controls.

INTERVENTIONS

The randomly allocated patients received intratympanic injection of BUD (0.5 mg/1 ml), DEX (2 mg/1 ml), or 0.9% NS solution (1 ml) once a week.

MAIN OUTCOME MEASURES

Survival analysis was applied to compare the longitudinal curative effects among the 3 groups. Meanwhile, the 6 main subjective symptoms were scored by 10-point visual scale, and physician's evaluations were preformed during treatment and follow-up.

RESULTS

After adjustment for course of disease, volume, and characters of effusion, the relative risk (RR) of BUD is 0.139 (95% CI, 0.054-0.358) when compared with NS. Survival curve demonstrated that the rank of longitudinal therapeutic efficacy was BUD, DEX, and NS (p < 0.05). Both BUD and DEX showed improvements in subjective symptoms and quality of life compared with NS (p < 0.05). In the aspect of improving the symptom of stuffy ear, BUD showed advantage over both DEX and NS. During and after treatment, no serious complications or sequelae were observed.

CONCLUSION

Intratympanic injection with BUD for OME patients showed advantages in improving long-term therapeutic efficacy, it was a safe and effective intervention for adolescents and adults with OME.

Oral steroid treatment for hearing improvement in Ménière's disease and endolymphatic hydrops

OBJECTIVE

To determine the effect of oral steroid treatment on hearing in unilateral Ménière's disease and endolymphatic hydrops patients.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary referral center.

PATIENTS

All patients presenting during the 2010 calendar year with confirmed unilateral Ménière's disease or endolymphatic hydrops. Those with a first visit and second visit audiogram (n = 58) were included in the analysis of oral steroid treatment effect.

INTERVENTION

Steroid treatment for hearing loss.

MAIN OUTCOME MEASURE

Change in hearing, as defined by change in affected ear threshold values or speech discrimination score from pretreatment visit to posttreatment visit.

RESULTS

Hearing (threshold, speech discrimination score) in patients' affected ear did not significantly change from first visit to second visit after treatment with steroids relative to patients who did not receive steroid treatment.

CONCLUSION

The results of this and other studies would indicate that a Ménière's disease or endolymphatic hydrops patient is unlikely to experience an improvement in hearing from a short course of oral steroid. Clinically observed temporary improvement did not sustain over several months. Further work to elucidate the mechanisms underlying hearing loss in hydrops, perhaps focusing on the dendrite damage noted in animal models of hydrops, is warranted.

Intratympanic steroid treatment for sudden deafness: a meta-analysis of randomized controlled trials

BACKGROUND

The efficacy of intratympanic steroid (ITS) treatment in sudden deafness (SD) remains controversial. To shed light on this issue, we performed a systematic review of randomized controlled trials to assess the overall efficacy of ITS therapy and to clarify whether it is more suitable as a first-line approach (primary treatment) or as a salvage treatment when traditional systemic agents have failed.

METHODS

An electronic database search (MEDLINE and PubMed) was performed with the objective of identifying all studies published in the English language between January 1980 and November 2011 on the efficacy of ITS in the treatment of SD. All relevant articles were retrieved, and the related reference lists were reviewed systematically to identify other reports that could be included. Data were synthesized using the Mantel-Haenszel model. Results are expressed as odds ratio (OR) with 95% confidence interval (CI).

RESULTS

A total of 11 randomized studies including 472 subjects allocated to ITS and 453 controls were selected. Intratympanic steroid regimens used and treatments administered to controls varied widely across studies. When considering together trials investigating ITS therapy as a primary (n = 4) or salvage (n = 7) treatment, the common OR for recovery was 1.7 (95% CI, 1.3-2.3). When considering them separately, the common ORs for recovery were 0.9 (95% CI, 0.7-1.6) for primary and 2.9 (95% CI, 1.9-4.5) for salvage therapy.

CONCLUSION

Intratympanic steroid therapy seems to confer a certain degree of benefit as a salvage but not as a primary treatment of SD. However, further evidence is needed to clarify some yet uncertain aspects, such as the optimal protocol of therapy.

Corticosteroid therapy for hearing and balance disorders

This review addresses the current status of steroid therapies for hearing and vestibular disorders and how certain misconceptions may be undermining the efficacy in restoring normal ear function, both experimentally and clinically. Specific misconceptions addressed are that steroid therapy is not effective, steroid-responsive hearing loss proves an underlying inflammatory problem in the ear, and steroids only have application to the hearing disorders listed below. Glucocorticoid therapy for hearing and balance disorders has been employed for over 60 years. It is recommended in cases of sudden hearing loss, Meniére's disease, immune-mediated hearing loss, and any vestibular dysfunction suspected of having an inflammatory etiology. The predominant steroids employed today are dexamethasone, prednisone, prednisolone, and methylprednisolone. Despite years of use, little is known of the steroid responsive mechanisms in the ear that are influenced by glucocorticoid therapy. Furthermore, meta-analyses and clinical study reviews occasionally question whether steroids offer any benefit at all. Foremost in the minds of clinicians is the immune suppression and anti-inflammatory functions of steroids because of their efficacy for autoimmune hearing loss. However, glucocorticoids have a strong binding affinity for the mineralocorticoid (aldosterone) and glucocorticoid receptors, both of which are prominent in the ear. Because the auditory and vestibular end organs require tightly regulated endolymph and perilymph fluids, this ion homeostasis role of the mineralocorticoid receptor cannot be overlooked in both normal and pathologic functions of the ear. The function of the glucocorticoid receptor is to provide anti-inflammatory and antiapoptotic signals by mediating survival factors.

Intratympanic steroid use for hearing salvage in Vogt-Koyanagi-Harada syndrome

We discuss the rare case of a 68-year-old woman with Vogt-Koyanagi-Harada (VKH) syndrome and sensorineural hearing loss (SNHL) who was successfully treated with intratympanic corticosteroid injections. The patient had presented with bilaterally asymmetric (i.e., moderate and moderate to severe) SNHL, tinnitus, vertigo, and vitiligo. She received two intratympanic injections in her worse-hearing ear over the course of 1 month. Subsequent audiometry showed an immediate 5- to 10-dB improvement in her hearing across multiple frequencies, as well as a long-term improvement to near-normal thresholds. The hearing thresholds in her untreated ear remained stable. To the best of our knowledge, this is the first report of a patient with VKH syndrome who was successfully treated with intratympanic steroid application.

Clinical Practice Guideline

Objective. Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence-based recommendations for the diagnosis, management, and follow-up of patients who present with SHL. The guideline primarily focuses on sudden sensorineural hearing loss (SSNHL) in adult patients (aged 18 and older). Prompt recognition and management of SSNHL may improve hearing recovery and patient quality of life (QOL). Sudden sensorineural hearing loss affects 5 to 20 per 100,000 population, with about 4000 new cases per year in the United States. This guideline is intended for all clinicians who diagnose or manage adult patients who present with SHL.

Purpose. The purpose of this guideline is to provide clinicians with evidence-based recommendations in evaluating patients with SHL, with particular emphasis on managing SSNHL. The panel recognized that patients enter the health care system with SHL as a nonspecific, primary complaint. Therefore, the initial recommendations of the guideline deal with efficiently distinguishing SSNHL from other causes of SHL at the time of presentation. By focusing on opportunities for quality improvement, the guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients.

Results. The panel made strong recommendations that clinicians should (1) distinguish sensorineural hearing loss from conductive hearing loss in a patient presenting with SHL; (2) educate patients with idiopathic sudden sensorineural hearing loss (ISSNHL) about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy; and (3) counsel patients with incomplete recovery of hearing about the possible benefits of amplification and hearing-assistive technology and other supportive measures. The panel made recommendations that clinicians should (1) assess patients with presumptive SSNHL for bilateral SHL, recurrent episodes of SHL, or focal neurologic findings; (2) diagnose presumptive ISSNHL if audiometry confirms a 30-dB hearing loss at 3 consecutive frequencies and an underlying condition cannot be identified by history and physical examination; (3) evaluate patients with ISSNHL for retrocochlear pathology by obtaining magnetic resonance imaging, auditory brainstem response, or audiometric follow-up; (4) offer intratympanic steroid perfusion when patients have incomplete recovery from ISSNHL after failure of initial management; and (5) obtain follow-up audiometric evaluation within 6 months of diagnosis for patients with ISSNHL. The panel offered as options that clinicians may offer (1) corticosteroids as initial therapy to patients with ISSNHL and (2) hyperbaric oxygen therapy within 3 months of diagnosis of ISSNHL. The panel made a recommendation against clinicians routinely prescribing antivirals, thrombolytics, vasodilators, vasoactive substances, or antioxidants to patients with ISSNHL. The panel made strong recommendations against clinicians (1) ordering computerized tomography of the head/brain in the initial evaluation of a patient with presumptive SSNHL and (2) obtaining routine laboratory tests in patients with ISSNHL.

Investigation of the cochlear effects of intratympanic steroids administered following acoustic trauma

OBJECTIVES/HYPOTHESIS

To electrophysiologically and histomorphologically demonstrate the effects of intratympanic corticosteroids administered following an acoustic trauma on cochlear hair cells.

METHODS

The trial was performed on 16 Wistar albino rats. The rats underwent distortion product otoacoustic emissions (DPOAE) measurement before the acoustic trauma, and subsequently rats were exposed to noise. Following acoustic trauma, the otoacoustic emission measurement was repeated. The rats were divided into two groups, a study group and a control group. The study rats were injected with methylprednisolone via the intratympanic route throughout the study. In the control group, the rats were injected daily with saline. After performing repeated otoacoustic emission measurements, one rat in each of the groups was sacrificed and their cochleae isolated.

RESULTS

The histological investigation performed after the 1st week revealed a statistically significantly higher rate of apoptotic cells in the inner and particularly the outer hair cells of the rat cochleae in the control group compared to the study group. Early measurement of DPOAE within the 1st week demonstrated significantly better amplitudes in the study group compared to controls. The otoacoustic emission assessment performed on the 14th day demonstrated statistically similar DPOAE values between the two groups.

CONCLUSIONS

Intratympanic methylprednisolone injection administered following an acoustic trauma appears to reduce cochlear outer hair cell loss. The impact on hearing loss is less certain. Early measurement of DPOAE within the 1st week shows significantly better amplitudes in the study group compared to controls. However at 2 weeks, there is no statistically significant difference in DPOAE amplitudes between the study and control group.

Combined intratympanic and systemic use of steroids for idiopathic sudden sensorineural hearing loss

OBJECTIVE

To compare hearing results in idiopathic sudden hearing loss patients treated with systemic steroids alone or combined intratympanic and steroids.

STUDY DESIGN

Prospective.

SETTING

Tertiary referral hospital.

PATIENTS

Idiopathic sudden sensorineural hearing loss patients.

INTERVENTIONS

The patients in the systemic therapy group received consecutive administration of 100 mg intravenous methylprednisolone in the first day, 80 mg/day oral prednisolone in 3 divided doses for the next 2 days, and continued with oral administration of steroids by tapering the dose 20 mg in every 2 days. The patients in the combined treatment group received intratympanic injection of methylprednisolone (an approximate dose of 0.5 ml of 125 mg/ml). A total of 5 injections on alternate days were performed.

MAIN OUTCOME MEASURES

The mean and median PTA gains of systemic corticosteroid therapy (SCT) group were 7.5 and 5 dB at 5th day, 12.1 and 7.5 dB at 10th day, and 13.0 and 8.8 dB at 15th day. The mean and median PTA gains for combined treatment (CT) group were 12.5 and 7.5, 17.8 and 13.8, 21.8 and 20.0 dB, respectively.

RESULTS

Both the mean and the median PTA gains were statistically significantly different between SCT and CT groups. According to improved hearing results (more than 10 dB gain), there was statistically significant difference between SCT and CT groups. None of the patients had an important complication.

CONCLUSION

The results of this study suggest that adding intratympanic methylprednisolone to systemic therapy increases the probability of hearing recovery in ISSHL patients.

Incidence of tympanic membrane perforation after intratympanic steroid treatment through myringotomy tubes

Intratympanic (IT) steroids are often used to treat inner ear disorders such as sudden idiopathic sensorineural hearing loss, autoimmune inner ear disease, and Ménière disease. Administration of corticosteroids via IT injection, via application with a pledget to the round window, or via catheter has been used for this purpose. The frequency of adverse events related to the IT injection of steroids is low, with pain, short-lasting vertigo, otitis media, and tympanic perforations being the most common complications. However, the safety of IT steroid therapy has not yet been established in a randomized clinical trial. In this article, we discuss a group of 11 patients with sensorineural hearing loss who underwent myringotomy and tube placement for home-based dexamethasone instillation and subsequently developed the complication of tympanic membrane perforation. It appears that there is a significantly increased incidence of tympanic membrane perforations in this population.

Intratympanic Steroids for Sudden Sensorineural Hearing Loss

Objective. To determine the evidence for efficacy of intratympanic (IT) steroid treatment for the management of idiopathic sudden sensorineural hearing loss through a systematic review of the existing literature.

Data Sources. Online databases consisting of PubMed, Medline, OVID, Google Scholar, Cochrane Review, and collected additional publications cited in bibliographies.

Review Methods. Literature search by both authors with structured criteria to select studies evaluated for systematic review.

Results. The authors identified 176 articles, of which 32 represented studies of initial or salvage intratympanic steroid injections for sudden hearing loss that included 6 randomized trials and only 2 randomized controlled trials. Despite the paucity of well-executed trials, the vast majority of studies of intratympanic steroids for salvage treatment in all tiers demonstrated a benefit of intratympanic steroid therapy. A limited meta-analysis of the higher quality studies revealed a mean difference in improvement of 13.3 dB (95% confidence interval [CI], 7.7-18.9; P < .0001). Although statistically significant, it is still unclear if this difference is clinically significant. Initial intratympanic therapy was equivalent to standard therapy in the existing literature of all qualities.

Conclusion. Intratympanic steroid treatment as primary treatment for sudden sensorineural hearing loss appears equivalent to treatment with high-dose oral prednisone therapy. As salvage therapy, intratympanic steroids offer the potential for some degree of additional hearing recovery, although it remains uncertain if this improvement is clinically significant and what percentage of patients is likely to show benefit.

Intratympanic steroids for Ménière's disease or syndrome

BACKGROUND

Ménière's disease is a disorder characterised by hearing loss, tinnitus and disabling vertigo. The use of intratympanic steroids to reduce the severity of these symptoms has been gaining popularity.

OBJECTIVES

To assess the effectiveness of intratympanic steroids on the frequency and severity of attacks of vertigo, on chronic symptoms such as tinnitus, imbalance and hearing loss, and on the progression of these symptoms in patients with definite Ménière's disease or syndrome, as defined by the AAO-HNS Committee.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the most recent search was 13 January 2011.

SELECTION CRITERIA

Randomised controlled trials of intratympanic dexamethasone versus placebo in patients with Ménière's disease.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial risk of bias and extracted data. We contacted study authors for further information where possible.

MAIN RESULTS

A single trial containing 22 patients, with a low risk of bias was included. This trial found that after 24 months, compared with placebo, the use of intratympanic dexamethasone demonstrated a statistically significant improvement in vertigo as defined by a respective improvement in functional level (90% versus 42%), class (82% versus 57%), change in Dizziness Handicap Inventory scores (60.4 versus 41.3) and mean vertigo subjective improvement (90% versus 57%). The treatment regime described by the authors involved daily injections of dexamethasone solution 4 mg/ml for five consecutive days. These results were clinically significant. No complications were reported.

AUTHORS' CONCLUSIONS

The results of a single trial provide limited evidence to support the effectiveness of intratympanic steroids in patients with Ménière's disease. This trial demonstrated a statistically and clinically significant improvement of the frequency and severity of vertigo measured 24 months after the treatment was administered. It is important to note that there were a few aspects of the study which we were unable to clarify with the study authors.

Intratympanic dexamethasone as initial therapy for idiopathic sudden sensorineural hearing loss: Clinical evaluation and laboratory investigation

OBJECTIVE

To evaluate the effect of intratympanic dexamethasone (ITD) as initial therapy for idiopathic sudden sensorineural hearing loss (ISSHL) as well as to determine the concentration-dependent time course distribution of dexamethasone in the inner ear.

METHODS

Sixty-six patients with profound ISSHL were included. Twenty-two were treated with ITD and the rest as control. Audiograms were performed before the treatment and one month afterwards. In the animal study, dexamethasone of different concentrations (5, 10 and 20mg/ml) was injected into the tympanums of three groups of SD rats (Groups A, B and C), their inner ears dissected free at various postinjection survival intervals. Immunofluorescence was applied to detect the locations of dexamethasone.

RESULTS

The overall rate of good prognosis was 77.27% in ITD group, which was not significantly different from 81.82% in the control group. In the animal study, the higher local concentration and longer lasting period was found in Groups B and C.

CONCLUSIONS

ITD at 5mg/ml did not add effect to systemic steroids in improving hearing outcomes in patients with ISSHL. An increase in dexamethasone concentration led to large variations in pharmacokinetics in animal study, showing potential value in optimizing the drug delivery protocols and improving the therapeutic results.

Stealth-nanoparticle strategy for enhancing the efficacy of steroids in mice with noise-induced hearing loss

AIMS

This study aimed to investigate the efficacy of encapsulating steroids, which is a primary choice for the treatment of sensorineural hearing loss, in polyethylene glycol-coated polylactic acid nanoparticles for drug delivery to the cochlea.

MATERIALS & METHODS

We prepared polyethylene glycol-coated polylactic acid nanoparticles encapsulating rhodamine or betamethasone phosphate (BP), and administered them systemically to CBA/N mice previously exposed to intense noise. We assessed nanoparticle distribution using rhodamine fluorescence, BP concentrations in tissues, nuclear translocation of glucocorticoid receptors and the function and histology of the mouse cochleae.

RESULTS & CONCLUSION

Polyethylene glycol-coated polylactic acid nanoparticles delivered BP to cochleae over a sustained period, resulting in significant reductions in histological and functional damage to cochleae and indicating the potential therapeutic benefits of these nanoparticles for enhancing the delivery of BP in acute sensorineural hearing loss.

Round window membrane in Ménière's disease: a human temporal bone study

OBJECTIVES

To disclose the histopathologic findings of the thickness of the round window membrane and the presence of false round window membrane in Ménière's disease.

METHODS

Twelve temporal bones from 6 patients with bilateral Ménière's disease, 44 temporal bones from 23 patients with unilateral Ménière's disease, and 102 age-matched normal temporal bones from 56 individuals were histopathologically examined. The thickness of the round window membrane was calculated from 3 different places. In addition, the presence of false round window membrane was investigated in temporal bones with Ménière's disease and compared to the normal temporal bones.

RESULTS

A significant difference in the mean thickness of the round window membrane was observed in temporal bones with Ménière's disease compared with normal temporal bones. There was no significant difference in the thickness of the round window membrane between the diseased side and contralateral side in patients with unilateral Ménière's disease. A false round membrane was observed in 9 (25.7%) of 35 Ménière's disease cases and in 5 (4.9%) of 102 normal temporal bones.

CONCLUSION

The thickened nature of the round window membrane and the frequent presence of false round window membrane in patients with Ménière's disease may impede the intratympanic injection treatments. The thickened middle layer of the round window membrane may be related to perilymphatic pressure changes observed in patients with Ménière's disease.

Effect of steroid, carbogen inhalation, and lipoprostaglandin E1 combination therapy for sudden sensorineural hearing loss

PURPOSE

The purpose of this study was to evaluate the efficacy of combined therapy with steroid, carbogen inhalation, and lipoprostaglandin E(1) (lipo-PGE(1)) treatment and compare the results with other treatment modalities in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

SUBJECTS AND METHODS

The study group consisted of 670 patients diagnosed with unilateral ISSNHL. Two hundred patients (DCP group) were treated with steroid, lipo-PGE(1) and carbogen inhalation combination therapy, 194 patients (DC group) with steroid and carbogen inhalation, and 276 patients (D group) with steroid medication only. The therapeutic effects of the treatment groups were evaluated 2 months after treatment, using pure tone averages. Siegel's criteria for hearing improvement were used for the assessments.

RESULTS

The overall recovery rate after treatment was 57.5%. For each group, the recovery rate was as follows: 67.0% in the DCP group, 52.6% in the DC group, and 53.9% in the D group. The DCP group had a significantly better improvement rate than the other 2 groups. In addition, the DCP treatment was better than the other 2 groups for patients: less than 50 years of age, with an initial hearing loss less than 90 dB HL, had treatment started within 1 week from the onset of hearing loss, had tinnitus or an ascending type audiogram, and/or had no vertigo.

CONCLUSION

Steroid, lipo-PGE(1), and carbogen inhalation therapy was more effective than the other treatment modalities studied for patients with ISSNHL.

Middle-ear endoscopy and trans-tympanic drug delivery using an interventional sialendoscope: feasibility study in human cadaveric temporal bones

Objective:

This study aimed to assess the feasibility of using a 1.3 mm, semi-rigid, interventional salivary endoscope for middle-ear endoscopy, and as a trans-tympanic route for delivery of medication, in human cadaveric temporal bones.

Study design:

Human cadaveric study.

Methods:

Five temporal bones harvested from human cadavers were examined. A 1.3 mm, interventional sialendoscope was used to make endoscopy-assisted myringotomy incisions in the postero-inferior quadrant (n = 5) and the antero-inferior quadrant (n = 3).

Results:

Middle-ear examination was successful in all specimens (n = 5). Access to the round window niche and adequate visualisation of the round window were achieved in all five temporal bones (100 per cent). A guide wire could be navigated to the round window niche without difficulty. Other structures identified in all specimens included the incudostapedial joint, stapedius tendon, pyramidal eminence and facial nerve via an extended myringotomy incision. The anterior middle-ear space was also successfully examined through an endoscope-guided anterior myringotomy. The opening to the eustachian tube was visualised and cannulated with a guide wire in all preparations in which this was attempted (n = 3).

Conclusions:

The 1.3 mm, interventional sialendoscope allowed adequate visualisation of the eustachian tube, middle-ear space and round window niche, with interventional capabilities, in a cadaveric model. Our result validates the feasibility of its use for trans-tympanic drug delivery.

Blocking the glucocorticoid receptor with RU-486 does not prevent glucocorticoid control of autoimmune mouse hearing loss

BACKGROUND/AIMS

Glucocorticoids effectively manage autoimmune hearing loss, although the cochlear mechanisms involved are unknown. Previous studies of steroid-responsive hearing loss in autoimmune (lupus) mice showed glucocorticoids and mineralocorticoids were equally effective, suggesting the ion homeostasis functions of glucocorticoids may be as relevant as immunosuppression for control of autoimmune-induced inner ear disease. Therefore, to better characterize the role of the glucocorticoid receptor in autoimmune hearing loss therapy, its function was blocked with the antagonist RU-486 (mifepristone) during glucocorticoid (prednisolone) treatments.

METHODS

Following baseline auditory brainstem response (ABR) thresholds, MRL/MpJ-Fas(lpr) autoimmune mice were implanted with pellets providing combinations of 1.25 mg/kg of RU-486, 4 mg/kg of prednisolone, or their respective placebos. After 1 month, animals were retested with ABR and blood was collected for immune complex analyses.

RESULTS

Mice receiving no prednisolone (placebo + placebo and placebo + RU-486) showed continued declines in hearing. On the other hand, mice receiving prednisolone (prednisolone + placebo and prednisolone + RU-486) had significantly better hearing (p < 0.05) than the non-prednisolone groups. Immune complexes were significantly elevated in the placebo + RU-486 group, suggesting RU-486 effectively blocked glucocorticoid receptor-mediated immune suppression. These results showed that blockage of the glucocorticoid receptor with RU-486 did not prevent prednisolone's effects in the ear, suggesting its ion homeostasis actions via the mineralocorticoid receptor were more relevant in hearing control.

CONCLUSION

The mineralocorticoid receptor-mediated actions of glucocorticoids are potentially relevant in steroid-responsive hearing disorders, implying disrupted cochlear ion transport functions may underlie the vascular problems proposed in some forms of immune-mediated hearing loss.

Intratympanic administration of methylprednisolone reduces impact of experimental intensive impulse noise trauma on hearing

CONCLUSION

The present findings demonstrated that intratympanic methylprednisolone (MP) reduces the impact of impulse noise trauma on hearing and in part preserves the hair cells from death 1 h after exposure to intensive impulse noise.

OBJECTIVE

To examine the treatment efficiency of intratympanic MP (IT-MP) with different methods of administration on cochlear injury induced by exposure to intensive impulse noise.

MATERIALS AND METHODS

Fifty-five guinea pigs were assigned into six groups and exposed to intensive impulse noise, i.e. 60 impulses at 165 dB SPL peak pressure with 0.5 ms duration and 2 s intervals. The auditory brainstem response (ABR) was used to examine the hearing thresholds. Cochlear morphology was examined to estimate the inner and outer hair cell loss induced by impulse noise exposure. MP was applied as a rescue agent via different modalities of administration.

RESULTS

The ABR threshold value of IT-MP1 or IT-MP4 groups significantly decreased at 4 weeks as compared with the IT-NS (IT 0.9% physiological saline) group. The ABR threshold value of the group that received intramuscular administration of MP (IM-MP) also decreased at 4 weeks as compared with the IT-NS group. Significant hair cell loss was observed at the region 40-50% from the apex in the present model. Within this region, the residual hair cell number in the IT-MP1 or IT-MP4 groups was significantly greater than that in the IT-NS group.

Cisplatin-induced ototoxicity: effect of intratympanic dexamethasone injections

HYPOTHESIS

Intratympanic (IT) application of dexamethasone will reduce ototoxicity associated with systemic cisplatin therapy.

BACKGROUND

Cisplatin is a common chemotherapeutic drug often dose-limited by ototoxicity attributed to the formation of reactive oxygen and nitrogen species damaging critical inner ear structures. Steroids have been shown to reduce formation of reactive oxygen species and thus may reduce ototoxicity. In the present pilot study, we test this hypothesis by IT administration of dexamethasone in a novel murine model of cisplatin ototoxicity.

METHODS

Click- and pure-tone-evoked auditory brainstem responses (ABRs) in young CBA/J mice were measured. The first phase consisted of a dosing study to identify the optimal cisplatin dose for ototoxicity. In the next phase, ABR thresholds were measured in cisplatin-treated mice after 5 days of IT injection of 24 mg/ml of dexamethasone in 1 ear and normal saline in the opposite ear to serve as controls.

RESULTS

Intraperitoneal injection of 14 mg/kg of cisplatin induces significant hearing loss (click-evoked ABR threshold elevation = 12 +/- 7 dB, mu +/- standard error of the mean) with acceptable mortality (20%). The ears that received IT dexamethasone in cisplatin-treated mice had minimal ABR threshold shifts with the click, 8 and 16 kHz of stimuli. There was no significant difference between IT dexamethasone and IT saline ears at 32 kHz.

CONCLUSION

IT dexamethasone protected the mouse ear against cisplatin-induced ototoxicity in a frequency-dependent manner. The present results suggest that IT dexamethasone may be a safe, simple, and effective intervention that minimizes cisplatin ototoxicity without interfering with the chemotherapeutic actions of cisplatin.

Contemporary Role of Endolymphatic Mastoid Shunt Surgery in the Era of Transtympanic Perfusion Strategies

Objectives:

Although there exist undisputed methods to permanently silence the aberrant end organ, controversy surrounds the durable efficacy of non-ablative interventions. This study provides a contemporary review of our institution's clinical experience in performing endolymphatic mastoid shunt surgery (EMSS) in patients with medically refractory endolymphatic hydrops, or Meniere's disease.

Methods:

Between 1984 and 2002, 1,612 patients were referred to our institution with a diagnosis of Meniere's disease. Of these referrals, 1,172 patients met the criteria for Meniere's disease. Although 553 patients responded to medical management, 486 patients underwent EMSS and 133 patients had refractory disease that required chemical or surgical obliterative interventions. The retrospective study utilizes data collected on 226 patients who were followed for a minimum of 5 years.

Results:

Overall, 78% patients responded favorably to EMSS, according to the functional level scale and class categories delineated by the American Academy of Otolaryngology-Head and Neck Surgery 1995 guidelines for control of vertigo. According to the Arenberg anatomic classification for endolymphatic sac location, EMSS achieved adequate control of vertigo in 86% of type I cases, 90% of type II cases, and 82% of type III cases.

Conclusions:

Endolymphatic mastoid shunt surgery is a relatively safe, effective procedure for the long-term control of vertigo in patients with medically refractory Meniere's disease.

Randomised, double-blinded, placebo-controlled, clinical trial of ozone therapy as treatment of sudden sensorineural hearing loss

OBJECTIVE

To investigate the safety and efficacy of ozone therapy in adult patients with sudden sensorineural hearing loss.

DESIGN

Prospective, randomised, double-blinded, placebo-controlled, parallel group, clinical trial.

SUBJECTS

Forty-five adult patients presented with sudden sensorineural hearing loss, and were randomly allocated to receive either placebo (15 patients) or ozone therapy (auto-haemotherapy; 30 patients). For the latter treatment, 100 ml of the patient's blood was treated immediately with a 1:1 volume, gaseous mixture of oxygen and ozone (from an ozone generator) and re-injected into the patient by intravenous infusion. Treatments were administered twice weekly for 10 sessions. The following data were recorded: pre- and post-treatment mean hearing gains; air and bone pure tone averages; speech reception thresholds; speech discrimination scores; and subjective recovery rates.

RESULTS

Significant recovery was observed in 23 patients (77 per cent) receiving ozone treatment, compared with six (40 per cent) patients receiving placebo (p < 0.05). Mean hearing gains, pure tone averages, speech reception thresholds and subjective recovery rates were significantly better in ozone-treated patients compared with placebo-treated patients (p < 0.05).

CONCLUSION

Ozone therapy is a significant modality for treatment of sudden sensorineural hearing loss; no complications were observed.

Topical steroid therapy using the Silverstein Microwick in sudden sensorineural hearing loss after failure of conventional treatment

CONCLUSIONS

Local administration of steroids to the inner ear through the round window route improves hearing in patients after failure of conventional therapy.

OBJECTIVES

To determine if delivery of methylprednisolone to the round window can improve hearing after failure of conventional treatment for sudden sensorineural hearing loss (SSHL) administered for 10 days after the onset of the hearing loss.

PATIENTS AND METHODS

A Silverstein microwick was placed in the round window niche under local anesthesia and endoscopic control, allowing self-administration of methylprednisolone twice a day for 3 weeks. Treated patients were compared to a control group composed of similar patients, treated with the same systemic regimen but who did not receive local therapy.

RESULTS

Of the 12 patients enrolled in this nonrandomized prospective study, 8 patients showed an improvement of the pure tone average (PTA) and 4 remain stable. Of those who responded to perfusion, eight patients demonstrated a significant mean 24.5 +/- 12 dB improvement in PTA, and seven patients had a mean 17.5 +/- 18% improvement in discrimination, with five patients reaching 100% speech discrimination score (SDS). Patients in the control group did not show any improvement of the PTA.