Changes in Eustachian Tube Mucosa in Mice After Short-Term Tobacco and E-cigarette Smoke Exposure.

OBJECTIVES: To evaluate histologic changes in middle ear and eustachian tube (ET) mucosa of mice after exposure to tobacco or electronic cigarette (e-cigarette) smoke. To determine whether there were any mitigating effects of middle ear application of anti-IL-13 or the epidermal growth factor receptor antagonist AG1478 on noted changes within ET mucosa. STUDY DESIGN: Controlled animal study. METHODS: Fifty BALB/cJ mice were randomly assigned to one of five groups: A control group with no smoke exposure, two groups exposed to tobacco smoke, and two groups exposed to e-cigarette vapor. Within the exposed groups after 4 weeks of exposure, one ear was infiltrated with a saline hydrogel and the other ear with hydrogel of either Anti-IL-13 or AG1478. After four more weeks of exposure, the animals were euthanized and the ETs were evaluated for mucosal changes. RESULTS: Compared to control animals with no smoke exposure, there were significant decreases in the numbers of goblet cells within the ET mucosa of mice exposed to tobacco smoke and e-cigarette vapor. No significant differences in cilia, mucin, or squamous metaplasia were noted. Neither anti-IL-13 nor AG178 significantly altered goblet cell count in the ET mucosa of mice exposed to tobacco smoke; however, both agents significantly increased goblet cells within the ET mucosa of mice exposed to e-cigarette vapor. CONCLUSION: Short-term tobacco smoke and e-cigarette vapor significantly decrease goblet cell count in mouse ET mucosa. Middle ear application of both anti-IL-13 and AG1478 resulted in an increase in goblet cell count among mice exposed to e-cigarette vapor, but not to tobacco smoke. LEVEL OF EVIDENCE: NA Laryngoscope, 132:648-654, 2022.

Tobacco Smoke Exposure and Eustachian Tube Disorders in US Children and Adolescents.

OBJECTIVES: To describe the association between active, environmental tobacco smoke (ETS) exposure and the prevalence of eustachian tube dysfunction (ETD) in the U.S. pediatric population. STUDY DESIGN: Cross-sectional. SETTING: U.S. representative demographic and audiometric data from the National Health and Nutrition Examination Survey (NHANES);2005-2010. SUBJECTS AND METHODS: The study consisted of 2,977 children aged 12-19 years. ETD was defined as middle ear pressure <100mm H20. ETS was defined as non-active smoking in individuals with serum cotinine over the limit of detection (≥0.015 ng/mL) and <10 ng/mL(N = 1559). RESULTS: The prevalence of ETD was 6.1%. After multivariate adjustment for age, sex, body mass index, education level, ethnicity, or having a cold, sinus problem or earache during the last 24 hours, compared to unexposed children, the odds ratios (95% confidence interval) of ETD for those exposed to ETS ages 12-15 in the first, second and third tertile of cotinine concentrations were, respectively, 1.38 (0.53-3.60), 0.99 (0.53-3.60) and 2.67 (1.12-6.34). Similarly, the odds ratios (95% confidence interval) of ETD for those exposed to ETS ages 16-19 in the first, second and third tertile of cotinine concentrations were, respectively, 1.28 (0.48-3.41), 0.99 (0.40-2.48) and 2.86 (1.19-6.88). CONCLUSION: These data suggest that children and adolescents exposed to high concentrations of ETS may have an increased prevalence of ETD.

The effect of general anaesthesia and neuromuscular blockade on Eustachian tube compliance: a prospective study.

OBJECTIVE: The most common complications of hyperbaric oxygen treatment (HBOT) are related to pressure changes on gas-containing cavities. Therefore, inability to auto-inflate the middle ear may result in transient or permanent hearing loss. However, it seems that middle ear barotrauma (MEBt) does not develop more often in mechanically ventilated patients than in ambulatory patients. This might be explained by deep sedation of these patients. Therefore, the aim of this study was to determine whether anaesthesia and/or neuromuscular blockade can influence Eustachian tube (ET) function. METHODS: Forty patients who were undergoing surgery under general anaesthesia were enrolled in this prospective study. ET function was evaluated by tympanography performed three times: before induction of general anaesthesia (baseline), after induction with sufentanyl/propofol and after full blockade was achieved with a long-acting neuromuscular blocking agent. RESULTS: There were no differences in ear volume (P = 0.19) and ear pressure (P = 0.07). There was a significant variation in compliance on tympanography after the induction of general anaesthesia (P = 0.009). Compared to the baseline, this variation was characterized by an increase after induction of anaesthesia (24 ± 7.13%, P 〈 0.01) and neuromuscular blockade (23 ± 8.9%, P 〈 0.05). The difference between after induction and after neuromuscular blockade was not statistically significant (P = 0.13). DISCUSSION: The findings of this trial suggest that the administration of hypnotic drugs associated with opioids improves ET compliance. Therefore it may have favourable prophylactic effects on MEBt in ventilated intensive care unit patients scheduled for HBOT.

[Bacteriologic investigation of the Eustachian tube and the implications of perioperative antibiotics before balloon dilation]. / Bakteriologische Untersuchungen der Tuba auditiva und die Implikation einer perioperativen Antibiotikagabe vor Ballondilatation.

BACKGROUND: Balloon Eustachian Tuboplasty (BET) is a new minimally invasive treatment for chronic Eustachian tube dysfunction (ETD). Initially, perioperative prophylactic antibiotic therapy with ciprofloxacin 2 × 500 mg p.o. for 5 days was administered. This study aimed to characterize the bacterial flora in the ET, nose, and pharynx in patients with chronic obstructive ETD. Additionally, we investigated the necessity of perioperative antibiotic prophylaxis in BET patients. PATIENTS AND METHODS: We examined 40 patients undergoing BET: 20 patients with and 20 patients without perioperative antibiotic prophylaxis. All patients were followed-up for clinical signs and symptoms of local infection for at least 2 weeks after surgery. Following BET, the tips of 35 balloon catheters, as well as swabs from the nose and pharynx were sent for microbiologic analysis. RESULTS: None of these 40 patients had postoperative signs of infection. Of the swabs of the balloon catheters, 46% were sterile and 23% showed standard flora. The remaining 31% of swaps revealed specific bacteria. However, none of the nasal or nasopharyngeal swaps were sterile. CONCLUSION: Due to the lack of signs of postoperative infection in either investigated group, the authors no longer favor use of perioperative antibiotic prophylaxis in patients undergoing BET. The relevance of biofilms and pathogen colonization to ET function has recently been intensively discussed, and should be further investigated in future studies.

Heparin binding-epidermal growth factor-like growth factor for the regeneration of chronic tympanic membrane perforations in mice.

We aim to explore the role of epidermal growth factor (EGF) ligand shedding in tympanic membrane wound healing and to investigate the translation of its modulation in tissue engineering of chronic tympanic membrane perforations. Chronic suppurative otitis media (CSOM) is an infected chronic tympanic membrane perforation. Up to 200 million suffer from its associated hearing loss and it is the most common cause of pediatric hearing loss in developing countries. There is a need for nonsurgical treatment due to a worldwide lack of resources. In this study, we show that EGF ligand shedding is essential for tympanic membrane healing as it's inhibition, with KB-R7785, leads to chronic perforation in 87.9% (n=58) compared with 0% (n=20) of controls. We then show that heparin binding-EGF-like growth factor (5 µg/mL), which acts to shed EGF ligands, can regenerate chronic perforations in mouse models with 92% (22 of 24) compared with 38% (10 of 26), also with eustachian tube occlusion with 94% (18 of 19) compared with 9% (2 of 23) and with CSOM 100% (16 of 16) compared with 41% (7 of 17). We also show the nonototoxicity of this treatment and its hydrogel delivery vehicle. This provides preliminary data for a clinical trial where it could be delivered by nonspecialist trained healthcare workers and fulfill the clinical need for a nonsurgical treatment for chronic tympanic membrane perforation and CSOM.

Interventions for adult Eustachian tube dysfunction: a systematic review.

BACKGROUND: Eustachian tube dysfunction (ETD) is the inability of the Eustachian tube (ET) to adequately perform at least one of its functions: to protect the middle ear from sources of disease, to ventilate the middle ear, and to help drain secretions away from the middle ear. There are a number of treatment options for ETD, but there is little consensus about management. OBJECTIVES: To determine the clinical effectiveness of interventions for adult ETD and to identify gaps in the evidence to inform future research. DATA SOURCES: Twelve databases were searched up to October 2012 for published and unpublished studies in English (e.g. MEDLINE from 1946, EMBASE from 1974, Biosis Previews from 1969 and Cumulative Index to Nursing and Allied Health Literature from inception). References of included studies, relevant systematic reviews and regulatory agency websites were checked. REVIEW METHODS: A systematic review was undertaken. Controlled studies evaluating prespecified treatments for adult patients diagnosed with ETD were eligible. Uncontrolled studies with at least 10 participants were included for interventions where no controlled studies were found. Outcomes included change in symptoms severity/frequency (primary outcome), quality of life, middle ear function, hearing, clearance of middle ear effusion, early ventilation tube extrusion, additional treatment, adverse events and complications. All aspects of the review process were performed using methods to reduce reviewer error and bias. Owing to heterogeneous data, a quantitative synthesis could not be performed, and results were reported in a narrative synthesis. RESULTS: Nineteen studies were included: three randomised controlled trials (RCTs) and two non-RCTs evaluating pharmacological interventions or mechanical devices for middle ear pressure equalisation; and 13 case series and one retrospective controlled before-and-after study evaluating surgical interventions. None was conducted in the UK. All studies were small (11 to 108 participants). Most non-surgical studies reported including mixed populations of adults and children. All except two studies were at high risk of bias, and subject to multiple limitations. Based on a single RCT, nasal steroids showed no improvement in symptoms or middle ear function for patients with otitis media with effusion and/or negative middle ear pressure. Very short-term improvements in middle ear function were observed in patients receiving directly applied topical decongestants or a combination of antihistamine and ephedrine. Single trials found two pressure equalisation devices were each associated with significant short-term improvements in symptoms, middle ear function and/or hearing. Eustachian tuboplasty (seven case series) and balloon dilatation (three case series) were associated with improved outcomes. Positive results were also reported for myringotomy (two case series), directly applied topical steroids (one case series) and laser point coagulation (one controlled before-and-after study). High rates of co-interventions were documented. Minor complications of surgery and pharmacological treatments but no serious adverse effects were reported. LIMITATIONS: The evidence was limited in quantity and overall was of poor quality. No data were identified on several interventions despite extensive searches. CONCLUSIONS: It is not possible to draw conclusions regarding the effectiveness of any of the interventions for the treatment of adults with an ETD diagnosis, and there is insufficient evidence to recommend a trial of any particular intervention. Further research is needed to address lack of consensus on several issues, including the definition of ETD in adults, its relation to broader middle ear ventilation problems and clear diagnostic criteria. STUDY REGISTRATION: This study is registered as PROSPERO CRD42012003035. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

[ENT]. / ORL.

We selected once more from about 15000 abstracts published in 2011 a couple of papers focused on general practice. Regarding the ear, we will discuss the role of nasal corticoids in Eustachian tube dysfunction, the treatment of vestibular neuronitis, the role of the bone-anchored hearing aid, or the vestibular implant. Regarding the nose, the influence of tobacco on sinus surgery, the treatment of staphylococcus cases, and the role of neuronavigation. Regarding the throat, head and neck region, our focus was on potential new treatments of the future that might change our approach, and on the correlations between food and cancer.

Novel rat model of tympanostomy tube otorrhea.

OBJECTIVE: Tympanostomy tube otorrhea (TTO), caused by the presence of pathogenic bacteria in the middle ear, is the most common complication of TT insertion. No studies have described a reproducible animal model of TTO. We aimed to develop a rat model of TTO which, in turn, could be used to assay the levels of TNF-α and IL-1ß through the course of the infection. METHODS: The left Eustachian tubes of 55 male Sprague-Dawley albino rats were occluded with gutta-percha (ETO=Eustachian Tube Occlusion). Middle ear (ME) effusion was ascertained by weekly otomicroscopy. At 3 weeks tympanostomy tubes were placed bilaterally and the MEs were inoculated bilaterally with Streptococcus pneumoniae through the tubes. The rats were randomly assigned to one of two daily ototopical treatments: ciprofloxacin/dexamethasone (CDX) or placebo. The animals in each of the two treatment groups were further divided to receive 1, 2, 5 or 7 days of treatment. The rats were sacrificed after treatment was finished. The rates of otorrhea, positive middle ear (ME) cultures, and levels of TNF-α and IL-1ß in the ME fluid were measured. RESULTS: Left ETO followed by ME inoculation with S. pneumoniae and treatment with placebo resulted in persistent infection (100% culture-positive ME fluid at 10 days) and otorrhea (85.7%). Persistent infection of the left ear was accompanied by significantly elevated the levels of IL-1ß and TNF-α. Ears treated with CDX had lower rates of otorrhea at all time points and lower levels of IL-1ß and TNF-α. CONCLUSIONS: This study is the first to describe a reproducible animal model of acute TTO. Surgical obstruction of the ET, followed by TT placement and ME inoculation with S. pneumoniae induced persistent otorrhea and infection. Both IL-1ß and TNF-α appear to be potential markers of persistent middle ear infection. This novel model may be used in future studies of the pathogenesis and therapy of TTO.

Failure of fluorescence to reveal middle ear penetration of quinolone drops.

OBJECTIVE: To evaluate the utility of fluorescence to assess penetration of quinolone ear drops (EDs) through tympanostomy tubes (TTs), the middle ear, eustachian tube, and into the oropharynx. DESIGN: Before-and-after trial. SETTING: Academic, tertiary care hospital. PATIENTS: Young children undergoing TT placement for otitis media and adolescents or adults undergoing repair of tympanic membrane (TM) perforations were included. INTERVENTIONS: Fluorescence of ofloxacin otic solution and serial dilutions was assessed with a Wood's lamp in vitro. Passage of ototopically administered ofloxacin into the pharynx was assessed in patients at the time of TT placement or TM repair. The oropharynx was visualized for fluorescence with a UV light for up to 2 hours after otic instillation. MAIN OUTCOME MEASURE: Oropharyngeal fluorescence. RESULTS: Ofloxacin otic fluorescence was visible at up to a 1:4 dilution. Fluorescence was confirmed in vivo by placing 1 drop of ofloxacin into the posterior pharynx and visualizing it transorally. Fluorescence was not identified in any of 20 patients after TT placement and in any of 6 patients prior to tympanoplasty. Two patients undergoing tympanoplasty reported tasting the EDs. CONCLUSION: Fluorescence is not a satisfactory method of assessing quinolone ED penetration through TTs and TM perforations, the middle ear, and into the nasopharynx.

Management of eustachian tube dysfunction with nasal steroid spray: a prospective, randomized, placebo-controlled trial.

OBJECTIVE: To determine the efficacy of intranasal aqueous triamcinolone acetonide in treating the tympanometric signs and symptoms of eustachian tube dysfunction, such as otitis media with effusion and negative middle ear pressure. DESIGN: Randomized, placebo-controlled, double-blind prospective clinical trial. SETTING: Tertiary referral clinic. PATIENTS: Adults (≥18 years) and children (6-17 years) presenting with otitis media with effusion, negative middle ear pressure, or both. INTERVENTIONS: The 2 treatment arms consisted of aqueous triamcinolone or matching placebo administered once daily intranasally for 6 weeks. All subjects underwent tympanometry, otologic examination, and completion of a symptom questionnaire before and after treatment. MAIN OUTCOME MEASURES: Resolution of abnormal tympanometry and change in symptom scores (severity and frequency). RESULTS: Ninety-one patients presenting from September 1, 2005, through December 31, 2008, with otitis media with effusion or with negative middle ear pressure were enrolled and randomly assigned to treatment or placebo in a double-blind manner. No statistically significant difference in normalization of abnormal tympanometric signs was demonstrated with the active treatment arm compared with placebo on either a per-patient basis (19% vs 32%; P = .18) or a per-ear basis (22% vs 35%; P = .15). There was also no significant difference in the overall poststudy symptom score between the 2 treatment arms, after adjusting for the prestudy overall symptom score in an analysis of covariance model (P = .27). CONCLUSION: These findings do not support the use of intranasal steroid sprays to treat the manifestations of eustachian tube dysfunction. Trial Registration clinicaltrials.gov Identifier: NCT00279916.

Simple mass loading of the tympanic membrane to alleviate symptoms of patulous eustachian tube.

BACKGROUND: Patulous eustachian tube (PET) has a major impact on a patient's quality of life. The purpose of this study was to understand mechanisms behind the symptoms, develop treatments based on these, and develop and use a questionnaire to measure changes in PET symptoms with a novel intervention. Our hypothesis is that PET symptoms can be addressed at the level of the eardrum more easily than at the level of the eustachian tube. METHODS: In a population of 14 PET subjects and 6 fresh temporal bones, several investigations were performed. Nasal audiometry was used to measure frequencies preferentially transmitted to the ear in PET subjects. An intervention consisting of mass loading of the eardrum was devised in the temporal bones to damp these frequencies. This was then applied to subjects with PET. A questionnaire was developed and administered to measure the response to this intervention. This questionnaire included the more common symptoms associated with PET, such as echoing sounds, increased environmental sounds, and a plugging sensation in the ear. Mass loading of the eardrum was performed with Blu Tack, a clay-like, nontoxic substance. RESULTS/CONCLUSION: Low frequencies are preferentially transmitted in PET, and eardrum vibrations to these can be mitigated with mass loading. Mass loading in human subjects significantly reduced major symptoms of PET, although temporarily.

[The rhinogenic deafness and SPA therapy: clinical-experimental study]. / Sordità rinogena e terapia termale: studio clinico-sperimentale.

OBJECTIVES: The sulphur SPA inhalation therapy is useful in respiratory and otolaryngologic chronic inflammatory diseases in adult subjects and children. The therapeutic action relies on anti-inflammatory, mucolytic and trophic effects. Particularly in children, the sulphur SPA inhalation therapy, using endotympanic ventilation or Politzer method, would be suitable in the treatment of the rhinogenic deafness. Several reports have demonstrated the effectiveness of endotympanic ventilation while the results on the Politzer method are inconclusive. On the basis of these considerations, aim of our study was to analyze the effectiveness and the safety of the aerosol+Politzer with a sulphur mineral water in children affected by rhinogenic deafness or chronic inflammatory processes responsible for the onset or persistence of rhinogenic deafness. PATIENTS AND METHODS: The study has been performed on 23 subjects in pediatric age (61% women and 39% males; mean age: 6+/-2.4 years; age range: 3-14 years) affected by chronic catarrhalis otitis, chronic rhino-pharyngitis inflammations, chronic or recurrent adenoiditis with dysfunction of the Eustachian Tube. The investigated subjects underwent 12 consecutive days sulphur SPA inhalation therapy (aerosol+Politzer) at the Terme of Stabia in Castellammare (Naples, Italy). At the beginning and at the end of the SPA cycle the functionality of the middle ear and the tolerability were evaluated. RESULTS: The results have shown an increase of the impedance curves that correspond to the normal ventilation of the tympanic box (type A (13% before therapy and of 57% post-therapy) and a decrease of the pathological curves of type B and type C (87% pre-therapy and of 43% post-therapy); a significant increase of compliance (p 0.05) in pathological curves of type B and C. No adverse reaction to the SPA inhalation therapy has been reported during the study. CONCLUSIONS: In concordance with the literature our data demonstrated that the sulphur SPA inhalation treatment induce a improvement of middle ear function of the subjects examined with good local and systemic tolerability.

Penicillin reduces eustachian tube gland tissue changes in acute otitis media.

OBJECTIVE: The volume of the mucous paratubal glands and the number of the mucus-producing goblet cells in the middle ear and Eustachian tube (ET) are increased after experimental acute otitis media (AOM). The present investigation examines a potential effect of penicillin on the changes in goblet cell density and gland structures of the ET during and after AOM. STUDY DESIGN: Middle ear inoculation of Streptococcus pneumoniae in 50 rats. Two days later, 25 rats were given penicillin V as one daily dose for 5 days. Twenty-five rats received no treatment. Five animals from each group were sacrificed on days 4, 8, 16, 90, and 180. The ET was dissected and decalcified, followed by paraffin embedding, serial transverse sectioning, and PAS/alcian blue staining. The goblet cell density and the paratubal gland composition and volume were determined in every 20th section, using a light microscope. RESULTS: Penicillin reduced the increase of goblet cell density from day 8 and through 6 months, whereas the increase of the paratubal mucous gland volume was unaffected by treatment. CONCLUSION: We conclude that penicillin reduces the increase of ET goblet cell density during and after acute otitis media, whereas the paratubal gland volume remains unaffected. An increased mucosal secretory capacity and indicated excessive secretion of mucus may contribute to the deteriorated ET function found after AOM and thus predispose, sustain, or aggravate middle ear disease. This may be prevented by penicillin treatment.

Avaliação de alterações timpanométricas em pacientes submetidos à anestesia geral com óxido nitroso

O óxido nitroso é um gás inalatório que pode aumentar a pressão intratimpânica durante o ato anestésico, bem como causar pressão negativa após sua suspensão, principalmente em pacientes com disfunção da tuba auditiva. Estas variações pressóricas podem trazer implicações clínicas, como ruptura de membrana timpânica, desarticulação da cadeia ossicular, hemotímpano, barotrauma, deslocamento de prótese de estapedotomia e lateralização do enxerto nas timpanoplastias, além da entrada de fluido seroso na orelha média durante a fase de pressão negativa. OBJETIVO: Avaliar a influência do óxido nitroso na pressão da orelha média em uma população sem disfunção tubária, realizando timpanometria no pré e pós-operatório. FORMA DE ESTUDO: Coorte transversal. MATERIAL E MÉTODO: Foi realizado um estudo prospectivo com pacientes internados no Hospital Universitário Clementino Fraga Filho - UFRJ, submetidos à anestesia geral com o uso do óxido nitroso a 50 por cento, durante o período de abril a julho de 2003. Avaliou-se ainda se a duração da cirurgia, anestésicos associados, presença de rinite alérgica e desvio de septo nasal poderiam influenciar no aparecimento das alterações da pressão intratimpânica. RESULTADOS: A amostra constituiu-se de 50 pacientes, encontrando-se em quase metade (48 por cento) alterações timpanométricas no pós-operatório (curva tipo C), quando comparado às de controle do pré-operatório (curva tipo A). Sexo e idade não interferiram no aparecimento das alterações timpanométricas no pós-operatório, bem como a duração da cirurgia. O tipo de anestésico volátil associado, desvio de septo nasal e rinite alérgica não exerceram influência na pressão da orelha média no pós-operatório. CONCLUSÃO: O óxido nitroso altera a pressão na orelha média tanto na fase de indução quanto na fase de resolução anestésica.

[Evaluation of tympanometric alterations in patients subject to general anesthesia with nitrous oxide]. / Avaliação de alterações timpanométricas em pacientes submetidos à anestesia geral com óxido nitroso.

UNLABELLED: The nitrous oxide is an inhaling gas that can increase intratympanic pressure during the anesthetic act and cause negative pressure after it is discontinued, mainly in patients with Eustachian tube dysfunction. These pressure variations may come up with clinical implications such as tympanic membrane rupture, ossicular system disarticulation, haemotympanum, barotraumas, prosthesis displacement stapaedotomy and tympanic graft lateralization after tympanoplasty, in addition to serous fluid entrance into the middle ear during the negative pressure phase. AIM: To evaluate the nitrous oxide influence on the middle ear pressure in a population without tube malfunction performing pre and postoperative tympanometry. STUDY DESIGN: Transversal cohort. MATERIAL AND METHOD: A prospective study was carried out with Universitário Clementino Fraga Filho Hospital- UFRJ intern patients, subject to general anesthesia with the use of 50% nitrous oxide from April to June 2003. It was also evaluated whether the duration of surgery, associated anesthetics, presence of allergic rhinitis and nasal septal deviation could contribute to the appearing of intratympanic pressure alteration. RESULTS: The sample is made up of 50 patients, in almost half of them (48%), postoperative tympanometry alterations (type C curve) were found, when comparing to the preoperative tympanometric control (type A curve). Neither sex nor age interfered in the appearing of tympanometry alterations during the post operative as well as the surgery timing. The anesthetic type volatile associate, nasal septal deviation and allergic rhinitis were not able to influence during the postoperative middle ear pressure. CONCLUSION: The nitrous oxide modifies intratympanic pressure during the anesthetic act as well as after it was discontinued.

Therapeutic improvement of Eustachian tube function: a review.

An impaired Eustachian tube is assumed to be an important factor in the pathogenesis of different middle ear diseases. Therefore, several investigators have studied different treatment strategies to improve Eustachian tube function. The aim of this review is to provide a comprehensive summary of the results of these studies on improvement of tubal function. The English language literature was searched systematically to identify all articles that described the effect of different interventions on Eustachian tube function. Although the results were not uniform throughout the different studies and despite several restrictions of the reviewed studies, the results of this review indicate that the function may be improved by medical intervention. However, it seems premature to recommend any of the interventions reviewed in this paper to improve function in humans. More studies, preferably randomized, placebo-controlled trials, should be conducted to assess the efficacy of different interventions.

Function of the eustachian tube after weekly exposure to pepsin/hydrochloric acid.

OBJECTIVE: To determine the effects of repeated pepsin/hydrochloric acid (HCl) exposure on the eustachian tube (ET). STUDY DESIGN AND SETTING: ET function was studied in 22 rats. Group I (control) rats received transtympanic phosphate buffered saline solution; groups II (0.5 mg/ml) and III (2.0 mg/ml) received transtympanic pepsin/HCl. Test solutions were applied on day 0 with ET function evaluated on days 1, 2, 3, and 7 after exposure. Each 7-day period represents 1 cycle; all groups underwent 4 cycles. ET function was evaluated using passive opening and closing pressure, and active clearance of positive and negative pressure tests. RESULTS: Rats exposed to pepsin/HCl had elevated passive opening pressures and a decreased ability to clear positive and negative pressure. A temporal relationship exists. CONCLUSION: The results suggest middle ear exposure to pepsin/HCl leads to ET dysfunction in rats, and that this dysfunction is enhanced with repeated exposures. SIGNIFICANCE: Gastroesophageal reflux may induce ET dysfunction.

Action of histamine on eustachian tube function.

INTRODUCTION: The role of allergy in eustachian tube dysfunction is controversial. In this study, allergy was simulated by exposure to histamine, and eustachian tube function testing was performed in an experimental rat model. METHODS: Ventilatory function was assessed by measuring passive opening and closing pressures of the eustachian tube after challenge with either transtympanic or intranasal histamine. The mucociliary clearance time of the tubotympanum was assessed by observing dye transport from the middle ear to the nasopharynx after challenge with either transtympanic histamine or control solution. RESULTS: There was a statistically significant increase in passive opening and closing pressures with transtympanic histamine versus intranasal histamine. In addition, mucociliary clearance times of the tubotympanum after transtympanic histamine showed a statistically significant increase when compared with those after transtympanic control solution. CONCLUSIONS: Transtympanic histamine exposure causes eustachian tube dysfunction in the rat by increasing passive opening and closing pressures of the eustachian tube and impairing mucociliary clearance time.

Nebulized surfactant for experimentally induced otitis media with effusion.

Eustachian tube dysfunction frequently results in clinical evidence of otitis media with effusion (OME). Surface active substances, surfactants, are hypothesized to play a role in normal eustachian tube function. Recent work in a rodent model has demonstrated improved eustachian tube function with topical application of surfactants to the middle ear. A novel, noninvasive, and clinically practical method of delivering surfactant to the eustachian tube was studied in a gerbil model of OME. Otitis media with effusion was experimentally induced in 20 gerbils by transtympanic inoculation of heat-killed Streptococcus pneumoniae. This represents a well established model for creating a serous effusion in the gerbil that significantly increases eustachian tube opening pressure. Effusion developed in 27 of 40 ears (67.5%) after inoculation. An inhaled nebulized surfactant was used to treat the animals with microscopically confirmed OME in one or both ears. The treatment period was 5 days. Eustachian tube opening studies were performed on both affected and nonaffected animals. Successful eustachian tube opening pressures were obtained in 30 of 36 ears (83.3%). The mean opening pressure for ears without effusion (healthy ears) was 42.8 mmHg. The mean opening pressure for ears with effusion in animals treated with nebulized surfactant was 41.4 mmHg. The difference between these mean values was not statistically significant (t = 0.32; p > 0.50). This pilot study suggests that inhaled nebulized surfactant may be efficacious in treating eustachian tube dysfunction when manifested in disorders such as OME.