Efficacy of Pneumococcal Vaccine on Otitis Media: A Systematic Review and Meta-Analysis.

OBJECTIVE: To assess the effect of the pneumococcal vaccine (PCV) toward the surgical management and complications of otitis media. DATA SOURCES: MEDLINE, EMBASE, PubMed, Scopus, and clinicaltrial.gov. REVIEW METHODS: A systematic search was performed using a combination of keywords and standardized terms about PCV and surgical management or complications of otitis media. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, studies were screened by 3 independent reviewers. Risk of bias assessment, followed by meta-analysis in only randomized-controlled trials was conducted. Vaccine efficacy (VE) and 95% confidence interval (CI) were reported. RESULTS: Of the 2649 abstracts reviewed, 27 studies were included in the qualitative analysis and were categorized into 6 outcomes: tympanostomy tube insertion, otitis media with effusion (OME), mastoiditis, spontaneous tympanic membrane (TM) perforation, recurrent acute otitis media (AOM), and severe AOM. Fifteen studies were included in the meta-analysis to evaluate the rate of tympanostomy tube insertion, OME, and recurrent AOM. PCV was significantly more effective in lowering the rate of tympanostomy tube insertion (VE, 22.2%; 95% CI, 14.6-29.8) and recurrent AOM (VE, 10.06%; 95% CI, 7.46-12.65) when compared with the control group, with no significant difference in reducing the incidence of OME. The qualitative analysis revealed that PCV had efficacy in preventing severe AOM and spontaneous TM perforation but the effect on mastoiditis remained unclear. CONCLUSION: The PCV was effective in reducing the rate of tympanostomy tube insertion and the incidence of recurrent AOM with a nonsignificant effect in preventing OME in children.

The effect of passive smoking on the etiology of serous otitis media in children.

Serous otitis media (SOM) is a disease mostly seen in the pediatric age group and characterized by serous effusion in the middle ear. The disease which is mostly silent can cause permanent hearing loss if it is not diagnosed and treated early. Passive smoking is one of the environmental factors in the etiopathology of the disease and risk factors for SOM formation in children. In our study, smoking habits of family members of 75 children with SOM and 50 healthy controls were investigated. At the end of the study, the correlation between SOM and passive smoke exposed was statistically significant in children (p < 0.01). In this study, the effect of passive smoking, which is a preventable and controllable risk factor in the etiology of the SOM in children is emphasized.

Tympanostomy tube otorrhea in children: prevention and treatment.

PURPOSE OF REVIEW: One in two children treated with tympanostomy tubes, experience episodes of otorrhea whilst their tubes are in place. In this review, we present the results of the most recent publications on prevention and treatment of tympanostomy tube otorrhea (TTO). RECENT FINDINGS: Recent systematic reviews on water precautions for children with tympanostomy tubes support the American Academy of Otolaryngology - Head and Neck Surgery guideline recommendation against such preventive measures as there is no evidence that it protects against TTO. Studies on tympanostomy tube design and material suggest that silicone tubes have a lower TTO risk and that biofilms appear to be mainly located in the perpendicular junction of the T-tubes and the round rims of the Paparella-type tubes. Another study shows that the biofilm-component DNAB-II protein is present in otorrhea of half of children with TTO. Targeting this protein could lead to a collapse of the biofilm structure and as such a potential new treatment for chronic TTO. New systematic reviews show that antibiotic eardrops are the most effective first-line treatment of acute TTO and suggest that an antibiotic-corticosteroid combination is more effective than antibiotic only. Although in many countries, quinolone eardrops are the preferred choice because of being non-ototoxic, one study found a higher risk of persistent perforation after tube extrusion in children treated with quinolone eardrops as compared with children treated with aminoglycoside eardrops. SUMMARY: Recent evidence confirms that water precautions for children with tympanostomy tubes are not effective in preventing TTO. Antibiotic-corticosteroid eardrops are the most effective treatment of acute TTO.

Grommet Surgery in Children With Orofacial Clefts in England.

OBJECTIVE: To assess grommet insertion practice in the first 5 years of life among children with an orofacial cleft in England. DESIGN: Analysis of national administrative data of hospital admissions. SETTING: National Health Service hospitals, England. PATIENTS: Patients born between 1997 and 2005 who underwent surgical cleft repair. INTERVENTION: Children receiving grommets before the age of 5 years. OUTCOME MEASURES: The proportion of children receiving grommets before the age of 5 years, the timing of the first grommet insertion, and the proportion of children having repeat grommet insertions were examined according to cleft type, the absence or presence of additional anomalies, socioeconomic deprivation, and region of residence. RESULTS: The study included 8,269 children. Before the age of 5 years, 3,015 (36.5%) children received grommets. Of these, 33.2% received their first grommets at primary cleft repair and 33.3% underwent multiple grommet insertion procedures. The most common age for the first procedure was between 6 and 12 months. Children with a cleft affecting the palate were more likely to receive grommets than children with a cleft lip alone (45.5% versus 4.5%). Grommet insertion practice also varied according to year of birth, absence or presence of additional anomalies, socioeconomic deprivation, and region of residence. CONCLUSION: Grommets practice in children with a cleft appears to vary according to their clinical characteristics. The differences in practice observed according to deprivation and region of residence need to be further explored.

Alloiococcus otitidis y su rol en la otopatía serosa / Alloiococcus Otididis and its role in the otitis media with effusion / Alloiococcus otitidis e seu papel na otitis media com efusão

Introducción: la otopatía serosa es generalmente considerada como una continuación directa del proceso inflamatorio que ocurre durante los episodios prolongados o recurrentes de otitis media aguda. El cultivo de fluido de oído medio en niños con esta patología, identifica en un 50-60% de los casos a tres gérmenes: Streptococcus pneumoniae, Haemophilus influenzae y Moraxella catharralis. Algunos autores utilizando técnicas no convencionales, han sugerido a Alloiococcus otitidis como un germen adicional, quien fuera descripto inicialmente por Faden y Dryja en 1989. Métodos: Se realizó una búsqueda bibliográfica en la base de datos MEDLINE entre los meses de enero a julio de 2016, utilizando las palabras claves Alloiococcus otitidis, biofilm, oído medio, microbiología y otopatía serosa, encontrándose 57 artículos que coincidieran con dichos términos. Fueron seleccionadas 34 citas bibliográficas. Resultados: Su frecuente localización, su identificación en efusiones de larga duración y de apariencia mucoide y su asociación con células inflamatorias le sugieren un papel protagónico gracias a su facilidad de formar biofilm. Conclusiones: Entender que las infecciones bacterianas crónicas están relacionadas a biofilms es fundamental en el desarrollo de estrategias racionales para su tratamiento y prevención.

Introduction: the otitis media with effusion is generally regarded as a direct continuation of the inflammatory process that occurs during prolonged or recurrent episodes of acute otitis media. The culture of middle ear fluid of children with this disease, identified in 50-60% of cases three organisms: Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis. Some authors, using unconventional techniques, have suggested Alloiococcus otitidis as an additional germ, who was initially described by Faden and Dryja in 1989. Methods: A bibliographic search was performed in the MEDLINE database from January to July 2016, using the keywords Alloiococcus otitidis, biofilm, middle ear, microbiology and serous otopathy, with 57 articles matching those terms. 34 bibliographic citations were selected. Results: Their common location, identification in effusions durable and mucoid appearance and association inflammatory cells would suggest a major role thanks to its ease of forming biofilm. Conclusion: Understand that chronic bacterial infections are related to biofilms is essential in the development of rational strategies for treatment and prevention.

Introdução: otopatía serosa é geralmente considerado como uma continuação directa do proceso inflamatório que ocorre durante episódios prolongados ou recorrentes de otite média aguda. A cultura do fluido do ouvido médio de crianças com esta doença, identifica em 50-60% dos casos três organismos: Streptococcus pneumoniae, Haemophilus influenzae e Moraxella catarrhalis. Alguns autores, utilizando técnicas não convencionais, ter sugerido a Alloiococcus otitidis como um germe adicional, que foi inicialmente descrita por Faden e Dryjaem, 1989. Metodos: a pesquisa bibliográfica foi realizada na base de dados medline de janeiro a julhode 2016, utilizando as palavras-chave alloiococcus otitidis, biofilme, do ouvido médio, microbiologia e otopatía serosa, sendo 57 itens correspondentes a esses termos. Entre eles foram selecionados 34 referências. Resultados: Sua localização frequente, identificação em derrames aparência de longa duração e mucóide e associação com células inflamatórias sugeriría um papel de liderança graças à sua facilidade de formação de biofilme. Conclusão: entenda que as infecções bacterianas crônicas estão relacionados com biofilmes é essencial para o desenvolvimento de estratégias racionais para tratamento e prevenção.

Using Pneumococcal Carriage Data to Monitor Postvaccination Changes in the Incidence of Pneumococcal Otitis Media.

Pneumococcal conjugate vaccines (PCVs) have substantially reduced the burden of pneumococcal disease, including the incidence of otitis media (OM). However, in most countries, no surveillance exists to monitor the change in pneumococcal OM incidence after the introduction of PCVs. We explored whether measuring pneumococcal carriage was a useful surrogate for monitoring postvaccination changes in the incidence of pneumococcal OM. The 7-valent PCV was introduced to Israel's national immunization program in July 2009 and gradually replaced by the 13-valent PCV starting in November 2010. Each day since 2009, nasopharyngeal swabs have been obtained from the first 4 Bedouin children and the first 4 Jewish children who were younger than 5 years old and attended a pediatric emergency room in southern Israel. During the same time, OM surveillance in southern Israel included all children younger than 2 years of age who were diagnosed with OM and had undergone a middle-ear fluid culture. The relative change in the prevalence of vaccine-serotype (VT) pneumococcal carriage was predictive of the relative change in incidence of OM due to VT pneumococcus. However, the serotype replacement observed in non-VT carriage is not paralleled in the incidence of OM due to non-VT pneumococcus. This could indicate that there are more complex mechanisms of the immune response involved in preventing initial and consecutive episodes of OM, which has been changed through declining prevalence of the most virulent serotypes as a result of vaccination.

The water penetration of different ventilation tubes.

The insertion of middle ear ventilation tubes remains one of the most common procedures for ENT surgeons. A common concern amongst patients undergoing such procedures is the effect on their ability to partake in swimming and other water sports. Currently there is little evidence comparing the penetration ability of different water solutions encountered by swimmers. This study compares the water penetration of four different water solutions for Shah, mini-Shah, T tube and titanium bobbin ventilation tubes. A model was constructed to replicate a grommet inserted through a tympanic membrane using a syringe barrel, latex membrane and one of the ventilation tubes. Four solutions (sea water, chlorinated water, freshwater and soapy water) were then pipetted down the barrel until penetration of the tube occurred. The volume required for penetration was recorded. For all tubes soapy water was the most penetrating, followed by seawater. Titanium bobbins required significantly less of each solution for penetration. Mini-Shah grommets required significantly more of all solutions except soapy water for penetration to occur. Shah grommets were more resistant to chlorinated and sea water than T tubes. Mini-Shah grommets appear to protect against water penetration into the middle ear cleft and their use should be considered in patients who are keen water-sport enthusiasts. Furthermore, swimmers in sea or chlorinated water seem to be at higher risk than freshwater swimmers. Titanium bobbins were relatively easily penetrated by all four solutions and should be avoided in keen swimmers.

Otitis media with effusion: benefits and harms of strategies in use for treatment and prevention.

Otitis media with effusion (OME) is a common clinical condition that is associated with hearing loss. It can be diagnosed at least once in approximately 80% of preschool children: 30-40% of them have recurrent episodes, and 5-10% have chronic disease. OME, in recurrent and persistent cases, might significantly delay or impair communication skills, resulting in behavioral and educational difficulties. Several therapeutic approaches have been used to avoid these problems. Most, however, have not been adequately studied, and no definitive conclusions can be drawn. Official guidelines do not recommend the use of decongestants, antihistamines, steroids, or antibiotics. The data are too scanty to assess other interventions, although autoinflation, because it incurs neither cost nor adverse events, deserves attention. Surgical procedures (i.e., tympanostomy tube insertion and adenoidectomy as an adjuvant) can be useful in some cases. This review evaluates all the current OME treatments and preventive measures, including their possible adverse events.

Stenting of the eustachian tube to prevent otitis media with effusion after maxillary swing approach nasopharyngectomy.

OBJECTIVES/HYPOTHESIS: Our previous report recommended that the management of ipsilateral otitis media with effusion (OME) after maxillary swing nasopharyngectomy was observation. The idea of introducing a stent into the eustachian tube (ET) at the nasopharyngeal side after nasopharyngectomy may prevent postoperative OME. The purpose of this study was to examine the feasibility of intraoperative ET stenting and the efficacy of preventing ipsilateral OME formation. STUDY DESIGN: Prospective cohort study. METHODS: From 2009 to 2011, 28 patients with nasopharyngectomy via the maxillary swing approach were recruited. Patients with curative resection were recruited (n = 21). ET stenting was performed intraoperatively using a 16-gauge Angiocath (BD Medical Systems, Franklin Lakes, NJ) with dimensions of 1.7 mm × 30 mm. The stent stays inplace indefinitely. The otologic status was evaluated using otoscopy, pure-tone audiogram, and tympanogram at 3 months, 6 months, and 1 year after the surgery. The outcomes were analyzed and compared with historical control. RESULTS: There were 9 (43%) patients with no OME at 6 months after surgery, and 15 (71%) patients had no OME at 1 year postoperatively. The results were statistically significant (P < .0001) when compared with our historical control of no ET stenting. There was no incidence of adverse effects of the stenting, such as acute otitis media, dislodgement of the stent, otalgia, and nasal pain. CONCLUSIONS: ET stenting was feasible after nasopharyngectomy. ET stenting prevented a significant number of patients from suffering from ipsilateral OME and alleviated the symptoms of unilateral aural fullness and unilateral conductive hearing impairment up to at least 1 year after the surgery. ET stenting is recommended in all patients after maxillary swing nasopharyngectomy.

Extracts from the Cochrane Library: interventions for the prevention of postoperative ear discharge after insertion of ventilation tubes (grommets) in children.

The "Cochrane Corner" is a section in the journal that highlights systematic reviews relevant to otolaryngology-head and neck surgery, with invited commentary to aid clinical decision making. This installment features a Cochrane Review, "Interventions for the Prevention of Postoperative Ear Discharge after Insertion of Ventilation Tubes (Grommets) in Children," that concludes if a surgeon has a high rate of postoperative otorrhea in children, then saline irrigation or antibiotic ear drops at the time of surgery would significantly reduce that rate. If topical drops are chosen, a single application at the time of surgery is suggested to reduce the cost and potential for ototoxic damage (if applicable).

[Study on the preventive effect of the gelomyrtol forte from secretory otitis media in patients with nasopharyngeal carcinoma after radiotherapy].

OBJECTIVE: To observed the prevention efficacy of secretory otitis media after radiation therapy by the Myrtol Standardized Enteric Coated Soft Capsules. METHOD: Sixty patients with nasopharyngeal carcinoma who Diagnosis without secretory otitis media before radiation therapy were divided into experimental group and control group, 30 cases in each group. After the start of radiation therapy ,the experimental group patients oral the Myrtol Standardized Enteric Coated Soft Capsules, each 0.3 g, 3 times a day, 7 days a course of treatment, oral the medication three months, the patients in the control group received no treatment. 3 months and 6 months after the end of radiation therapy, whether there is a difference comparison of experimental group and the control group in symptoms, signs, pure tone audiometry and tympanogram change. RESULT: Seventeen patients (18 ears) (56.67%, 17/30) in the control group were suffering from secretory otitis media, 7 patients (7 ears) (23.33%, 7/30) in the experimental group were suffering from secretory otitis media. The difference between the two groups was statistically significant (P < 0.01). 17 patients (17 ears) in the control group and 7 patients (7 ears) in the experimental group were suffering from tinnitus. 20 patients(20 ears) in the control group and 9 patients (10 ears) in the experimental group have ear choking feeling. The difference between the two groups was statistically significant (P < 0.01). The air conduction hearing threshold of the experimental group before radiation therapy is (7.5 +/- 2.0) dB HL and the air conduction hearing threshold of the control group patients is (8.3 +/- 4.0) dB HL. The difference between the two groups was not statistically significant (P > 0.05). 3 months after radiation therapy,the gas conductive hearing threshold of the experimental group is (25.6 +/- 3.0) dB HL, but the data in the control group is (40.7 +/- 5.0) dB HL. The difference between the two groups was statistically significant (P < 0.01). CONCLUSION: Patients with nasopharyngeal carcinoma oral the the Myrtol Standardized Enteric Coated Soft Capsules before radiation therapy can effectively reduce the incidence of secretory otitis media after radiotherapy, it can prevent the occurrence of secretory otitis media.

[Recurrent otitis media with effusion in childhood : when should an otolaryngologist consider an allergic etiology?]. / Rezidivierendes Sero-/Mukotympanon im Kindesalter : Wann muss der HNO-Arzt an eine Allergie denken?

Up to 80 % of children can develop otitis media with effusion (OME) between birth and school age. Responsible are longstanding impairments of tubal ventilation which are based primarily on mechanical or functional obstructions. A quarter of the subjects affected by OME show either recurrent episodes over 3 months or protracted clinical courses and in these children an extended diagnosis is required. Besides infection-related adenoid hypertrophy, the differential diagnosis should include ciliary dysfunction, chronic rhinosinusitis, craniofacial malformations, gastroesophageal reflux, tumors and cancer treatment in the nasopharynx and in particular allergies. Clinical and experimental studies have indicated that respiratory allergies promote both adenotonsillar hypertrophy as well as inflammatory alterations in the mucous membranes of the Eustachian tube and middle ear and can thus promote the formation and persistence of OME. Because of a sensitization rate of about 30% in the general population at the predilection age from 3-6 years (KiGGS study), standard diagnosis (e.g. otoscopy and audiometry) should be extended by allergy diagnostic testing, especially in cases of recurrent or prolonged courses of OME. The most common classes of medications used for childhood allergies are antihistamines and nasal steroids, which could optimize the standard treatment of OME.

The effect of cleft palate repair technique on hearing outcomes in children.

OBJECTIVE: Otitis media with effusion causing conductive hearing loss is a problem for many children with cleft palate. This study examines the association between palate repair technique and hearing outcomes in children at 3 and 6 years post-repair. PATIENTS AND METHODS: Retrospective chart review of patients with all types of cleft palate that were repaired between 2001 and 2006 at a tertiary children's hospital. Exclusion criteria included sensorineural hearing loss, ossicular chain abnormalities, and ear canal abnormalities. The primary outcome was pure tone average (PTA) from 0.5 kHz to 2 kHz. RESULTS: 69 patients (138 ears) were analyzed. 30.4% of left ears and 31.9% of right ears had an abnormal (>20 dB) PTA at 3 years; at 6 years this significantly improved to 13.0% (p=0.008) and 15.9% (p=0.011). Double-reverse z-plasty was associated with the lowest median PTA of 10.0 dB (p=0.046) at 6 years. There was no difference in median PTA between children with and without comorbid diagnoses (such as Pierre Robin Sequence, arthrogryposis) at either 3 years or 6 years (p=0.075, p=0.331). Multivariate model showed that extent of cleft influenced technique choice (p=0.027), but only technique choice was associated with significant differences in PTA and only at 6 years post-repair. CONCLUSION: The majority of children developed normal hearing by 6 years with palatoplasty and routine tube insertion. Double reverse z-plasty was associated with the best outcome, but is not ideal for hard palate clefts. Randomized controlled trials are needed to elucidate the relationship between technique, middle ear ventilation and time to recovery, irrespective of type of cleft.

Can vaccination against pneumococci prevent otitis media with effusion?

The most common cause of hearing loss in early childhood is otitis media with effusion (OME). Prevention of OME in preschool children will improve quality of life. The authors aimed to determine, by the best available published evidence, whether vaccination against pneumococci effectively prevents OME. The study design was based on systematic review (SR) of randomized controlled trials (Level 1a evidence). The medical literature available through searching Medline database was reviewed using the following keywords "Otitis media with effusion," "secretory otitis media," or "glue ear," and "vaccination" limiting the search to randomized controlled trials (RCTs) conducted on children (0-18 years), published in English, in the last 10 years. Results of effects of vaccination on prevention of OME from the included RCTs were utilized to conduct a meta-analysis to find out the preventive value of antipneumococcal vaccination. Three RCTs were identified conforming to the inclusion criteria. Meta-analysis of results showed no significant preventive advantage for antipneumococcal vaccination. Based on the results it was confirmed that neither primary nor secondary prevention by antipneumococcal vaccination has a beneficial impact on OME. More RCTs should be conducted to study the effect of vaccination on OME.

Antibiotic therapy to prevent the development of asymptomatic middle ear effusion in children with acute otitis media: a meta-analysis of individual patient data.

OBJECTIVES: To determine predictors of the development of asymptomatic middle ear effusion (MEE) in children with acute otitis media (AOM) and to assess the effect of antibiotic therapy in preventing the development of MEE in these children. DATA SOURCES: A systematic literature search was performed using PubMed, EMBASE, the Cochrane databases, and the proceedings of international otitis media symposia. STUDY SELECTION: A trial was selected if the allocation of participants to treatment was randomized, children aged 0 to 12 years with AOM were included, the comparison was between antibiotic therapy and placebo or no (antibiotic) treatment, and MEE at 1 month was measured. DATA EXTRACTION: Data from 5 randomized controlled trials were included in the meta-analysis of individual patient data (1328 children aged 6 months to 12 years). We identified independent predictors of the development of asymptomatic MEE and studied whether these children benefited more from antibiotic therapy than children with a lower risk. The primary outcome was MEE (defined as a type B tympanogram) at 1 month. DATA SYNTHESIS: The overall relative risk of antibiotic therapy in preventing the development of asymptomatic MEE after 1 month was 0.9 (95% confidence interval, 0.8-1.0; P =.19). Independent predictors of the development of asymptomatic MEE were age younger than 2 years and recurrent AOM. No statistically significant interaction effects with treatment were found. CONCLUSION: Because of a marginal effect of antibiotic therapy on the development of asymptomatic MEE and the known negative effects of prescribing antibiotics, including the development of antibiotic resistance and adverse effects, we do not recommend prescribing antibiotics to prevent MEE.

Immune modulatory oligonucleotides in prevention of nasal allergen-induced Eustachian tube dysfunction in rats.

OBJECTIVES: Develop a model of nasal allergen-induced Eustachian tube dysfunction (ETD) in a rat and investigate the role of immune modulatory oligonucleotides (IMOs) in the prevention of nasal allergen-induced ETD. STUDY DESIGN AND SETTING: Prospective, randomized study. Brown Norway rats were sensitized to ova albumin (OVA) and randomized to receive pretreatment with IMOs or phosphate-buffered saline. All animals were challenged intranasally with aerosolized OVA. Dynamic measures of Eustachian tube (ET) function were analyzed. RESULTS: Animals that were OVA-sensitized and IMO-pretreated had significantly lower mean passive opening (95% confidence interval [95% CI] 15.0,19.4) and closing (95% CI 4.8,7.8) ET pressures compared with those of (95% CI 24.1,32.7) and (95% CI 12.1,18.8) OVA-sensitized untreated rats, respectively. In addition, the IMO-pretreated animals demonstrated the ability to actively clear a significantly higher proportion of negative pressure (95% CI 0.64,0.96) compared with the untreated animals (95% CI 0.09,0.39). IMO-pretreated animals also demonstrated significantly improved mean mucociliary clearance times in seconds (95% CI 115,195) than those in untreated animals (95% CI 308,668). CONCLUSIONS: Pretreatment with IMOs prevented allergen-induced allergic inflammation around the Eustachian tube (ET) and resulted in improved ventilatory function of the ET compared with sensitized untreated animals. IMOs offer considerable promise in the management of nasal allergic disease as well as otitis media with effusion.

Immune modulatory oligonucleotides in the prevention and treatment of OVA-induced eustachian tube dysfunction in rats.

BACKGROUND: Otitis media with effusion (OME) is often associated with allergies. Immune modulatory oligonucleotides (IMO) mediate allergic inflammation and may therefore be efficacious in the treatment of airway inflammation. OBJECTIVE: To evaluate the role of an IMO via transtympanic mucosal application in prevention and treatment of ovalbumin-induced OME. DESIGN: Forty brown Norway rats were divided into control and treatment groups. Eustachian tube dysfunction was evaluated by passive opening pressures, passive closing pressures, active clearance of negative pressure, and mucociliary clearance transit time. RESULTS: Rats who underwent IMO treatment required 50% less pressure to open and close the eustachian tube (P < 0.05) and were able to actively clear 50% more negative pressure than the ovalbumin-control rats (P < 0.001). The treatment rats' mucociliary clearance time was half that of the control group (P < 0.001). CONCLUSION: IMO via transtympanic application can prevent and treat allergy-induced eustachian tube dysfunction in rats. IMO may offer substantial promise in the future management of OME.