Direct measurement of middle ear pressure through the eustachian tube

Summary We report a method for measuring middle ear pressure through the eustachian tube. We used a 1-mm-diameter micro-tip catheter pressure transducer (Mikro-tip) and inserted this into the tympanic cavity through the eustachian tube. In preliminary studies, we measured four normal ears, two ears with tubal dysfunction, one ear with a dry perforation and 13 ears with otitis media with effusion (OME). Among those ears with OME, three showed negative middle ear pressure, three slight positive pressure and one normal pressure. These findings suggest that our transtubal method is reliable and useful for measuring middle ear pressure.     

Transtympanic endoscopic findings in patients with otitis media with effusion

Using a fine, rigid endoscope (Olympus, SES-1711K), we examined the middle ear, including the tympanic orifice of the eustachian tube, of children with otitis media with effusion (OME) in its active stage (26 ears), in the convalescent stage (13 ears), and during treatment with ventilation tubes for 10 days to 6 months (five ears) through myringotomy with the patients under general anesthesia. Several color photographs of representative ears are shown. In the active stage of OME, edema (73.1%) and hyperemia (23.1%) were characteristic features of the middle ear mucosa, and normal mucosa was seen in only one ear (3.1%). The tympanic orifice of the eustachian tube, which could be examined in 12 ears, were stenosed with edema in four ears (33.3%) or plugged with effusion in three ears (25.0%) in this group. In the convalescent stage of OME, dilated vessels were most often seen (69.2%), but the rest of the patients had normal mucosa (30.8%) in the middle ear, and none of them had edema nor hyperemia. The tympanic orifice of the eustachian tube, which could be examined in five ears, was clearly patent in all the patients in this group. One ear that was treated with a ventilation tube for 1 month showed dilated vessels and less severe inflammation than did ears that were in the active stage of OME, and three ears that were treated for more than 3 months showed almost normal middle ear mucosa.     

Site of eustachian tube dysfunction in patients with otitis media with effusion

This study was conducted to identify an exact site of ventilatory dysfunction within the eustachian tube among patients with otitis media with effusion (OME). Using 10 adults with OME, a fine polyethylene tube with a small pore at its tip was inserted into the eustachian tube via its pharyngeal orifice. Negative middle ear pressure was applied through a ventilation tube in the eardrum, and the patients were asked to swallow repeatedly at every 5-mm depth of insertion of the polyethylene tube toward the middle ear. Negative middle ear pressure could be equilibrated by swallowing within 10 mm of tube advancement from the pharyngeal orifice of the eustachian tube in seven of ten patients. It was concluded that the site of tubal ventilatory dysfunction is in the distal part of the cartilaginous portion of the eustachian tube in most adult patients with OME.     

Eustachian tube function before recurrence of otitis media with effusion

OBJECTIVE: To study the role of eustachian tube function in the development of recurrent otitis media with effusion (OME) in children treated with tympanostomy tubes for OME. DESIGN: Prospective cohort study. SETTING: Three academic and general hospitals. PATIENTS: Children aged 2 to 7 years with a first clinical episode of OME that persisted for at least 3 months; 136 (81%) of 168 eligible children participated. All children received tympanostomy tubes for bilateral OME at study entry. MAIN OUTCOME MEASURE: Recurrence of OME within 6 months of tube extrusion. RESULTS: No statistically significant differences were present in eustachian tube function test results between ears that developed recurrent OME and those that did not. The difference in passive ventilatory function between ears with and without OME recurrence was 10 daPa (95% confidence interval, -24 to 43 daPa) for opening pressure and -3 daPa (95% confidence interval, -18 to 11 daPa) for closing pressure. The overall difference in the proportion of ears with and without OME recurrence that could not equilibrate positive and negative applied pressures was 12% (95% confidence interval, -2% to 26%). The proportions of ears with and without OME recurrence that induced negative pressure in the middle ear by forcefully sniffing were 22% and 31%, respectively (P = .75). CONCLUSION: Measurement of ventilatory and protective eustachian tube function using the forced response test, the pressure equilibration test, and the sniff test has no value in predicting whether children have an increased risk of OME recurrence.     

Influence of the Gas Exchange Function Through the Middle Ear Mucosa on the Development of Sniff-Induced Middle Ear Diseases

To investigate the influence of gas exchange function through the middle ear mucosa on the development of sniff-induced middle ear diseases, the authors examined the mastoid pneumatization among patients with sniffing habit using computed tomography, and also examined the change of negative middle ear pressure induced by sniffing using tympanogram. In 20 ears with cholesteatoma or adhesive otitis media, the areas of mastoid cavity measured at the level of the lateral semicircular canal were significantly smaller than those in 26 ears with otitis media with effusion (OME) or attic retraction and in eight normal ears with sniffing habit (P < .01 and P < .0001, respectively). In 26 ears with OME or attic retraction, the areas of mastoid cavity were significantly smaller than those in eight normal ears with sniffing habit (P < .0001). By contrast, in the four ears with sniff-induced middle ear disease, the recovery of negative middle ear pressure in 5 minutes without swallowing was less than 10 mm H₂O, whereas in all seven ears with normal eardrum, negative middle ear pressure recovered by more than 20 mm H₂O in 5 minutes. These findings suggested that impairment of gas exchange function through the middle ear mucosa, as well as eustachian tube dysfunction, might be closely related to the development of sniff-induced middle ear diseases.     

Compliance of the eustachian tube in patients with otitis media with effusion

To analyze the compliance of the eustachian tube, we measured the decrease in tubal resistance (pressure/air flow) with increasing air flow rate through the eustachian tubal lumen. When the eustachian tube is compliant, the tubal resistance decreases greatly because of the high distensibility of the tube. The tubal compliance index (TCI), which is the ratio of the tubal resistance between two different air flow rates, was compared among three groups: 36 ears of children with otitis media with effusion (OME), 26 ears of adult OME patients, and 10 otherwise normal ears with traumatic perforations of the eardrum. Compared with normal subjects, OME children had a significantly higher TCI (P less than .005), whereas OME adults had a significantly lower TCI (P less than .05). From these results, we concluded that eustachian tubes are compliant in children with OME but rigid in adults with OME.     

The role of allergy in the pathogenesis of otitis media with effusion

To explain an allergic basis for the development of otitis media with effusion (OME), it was suggested that the middle ear mucosa can act as an allergic "shock organ." To evaluate this possibility, 16 juvenile rhesus monkeys were passively sensitized to pollen by intravenous injection of allergic human serum. All ears were then challenged by insufflation of pollen via the nose and eustachian tube (ET), twice daily, for four to five days. Daily tympanometry and otomicroscopy were performed, and on the last day of challenge, tympanocentesis was done to recover effusions. Five animals were killed and the middle ears were processed for histologic study. The results showed that none of the ears developed a middle ear effusion or OME. It is concluded that middle ear challenge with an appropriate pollen antigen in passively sensitized rhesus monkeys does not initiate an inflammatory reaction in the middle ear or induce OME.     

Negative middle ear pressure and otitis media with effusion after surgery under general anesthesia

Abstract Conclusion: Negative middle ear pressure was observed in many patients and otitis media with effusion (OME) developed in 3.3% of ears after surgery under general anesthesia. Gas dynamics in the middle ear cavity induced by nitrous oxide inhalation anesthesia and transient blockage of the eustachian tube induced by surgery are considered to be involved in development of OME after surgery under general anesthesia. Objectives: The goal of this prospective study was to investigate middle ear pressure and the prevalence of middle ear effusion in patients after surgery under general anesthesia, to ascertain whether surgery under general anesthesia induces OME. Methods: Otoscopic inspection and tympanometry were performed before surgery (Pre), 1-2 days after surgery (Post-1), and 5-9 days after surgery (Post-2) under general anesthesia in 180 ears of 97 adult patients. Results: Effusion accumulated in the tympanum in six ears (3.3%) of five patients at Post-1. All patients were anesthetized with nitrous oxide. At Post-2, effusion disappeared in all cases. The mean middle ear pressure in all ears was -17.8 daPa at Pre and -60.6 daPa at Post-1, showing a significant reduction from Pre to Post-1 (p < 0.001). At Post-2, the pressure was -18.4 daPa, with no significant difference from that at Pre (p = 0.74).     

The role of allergic rhinitis in the development of otitis media with effusion: effect on eustachian tube function

PURPOSE: The pathogenesis of otitis media with effusion (OME) is considered multifactorial, with viral upper respiratory tract infection and eustachian tube dysfunction. Allergy may be related to the pathogenesis of OME or to another etiological factor. We investigated the role of allergic rhinitis (AR) in children with OME and evaluated eustachian tube function in patients with AR. MATERIALS AND METHODS: We prospectively analyzed the prevalence of AR, serum eosinophil count, and serum total IgE concentrations in 123 children with OME and in 141 controls. IgE concentration in middle ear effusion was compared in children with OME with and without AR, and eustachian tube function after a nasal provocation test was compared between patients with AR and controls. RESULTS: The prevalence of AR in children with OME (28.4%) and control subjects (24.1%) did not differ significantly. These 2 groups also showed no differences in total eosinophil count and serum and middle ear effusion IgE concentration. Abnormalities in eustachian tube function were the same in patients with AR and controls. CONCLUSIONS: Allergic rhinitis may not be related to the development of OME in children.     

表面活性物质在分泌性中耳炎咽鼓管开放功能中的作用

目的　探讨外源性的表面活性物质在分泌性中耳炎咽鼓管开放功能中的作用。方法　通过鼓室内注入灭活的肺炎链球菌悬液 ,建立分泌性中耳炎动物模型 ,测试咽鼓管的被动开放压。结果　测试了中耳有渗液者 2 7耳和正常者 2 1耳的咽鼓管被动开放压 ,有渗液耳的被动开放压高于正常耳的被动开放压 ,分别注入外源性的表面活性剂后 ,被动开放压均降低 (P <0 .0 1)。结论　外源性的表面活性剂可以降低咽鼓管的表面张力 ,有利于咽鼓管的开放     

Long-Term Middle Ear Ventilation

Successful long-term middle ear ventilation was established in 12 patients with chronic eustachian tube hypofunction that had failed to respond to repeated myringotomy and tympanotomy tube insertions by conventional techniques. The 12 patients (13 ears) had insertion of an untrimmed large flange “Per-Lee” type tube through a posterior-inferior tympanomeatal flap approach. The flange extended under the long process of the malleus, and into the hypotympanum and middle ear opening of the eustachian tube. The stem of the tube was brought out through the inferior central pars tensa. All tubes have remained in place for more than three years without serious complications providing adequate middle ear ventilation and preventing adherence of the tympanic membrane to the promontory.     

Nebulized surfactant as a treatment choice for otitis media with effusion: an experimental study in the rabbit.

Exogenous surfactant can improve eustachian tube function in experimentally induced otitis media with effusion (OME). Performing tympanometric recordings, the efficacy of inhaled nebulized surfactant, as compared with inhaled nebulized physiological saline was investigated, for the treatment of OME experimentally induced in the rabbit by intrabullar inoculation of heat-killed Streptococcus pneumoniae. In addition, the histological changes in middle ears after the treatment were investigated in order to establish whether the pathological findings correlated with the results. Middle-ear pressure values before, and after, treatment were analyzed by the Wilcoxon statistical method, and the Mann-Whitney U test was used to compare the post-treatment values between groups. In all ears with OME in the affected animals, which were treated with nebulized surfactant inhalation, a positively significant (p<0.05) increase of pressure more than 20 daPa was recorded. In the control group, after inhalation of nebulized physiological saline, there was no positive increase in the affected middle-ear pressures; on the contrary, more negative pressure changes were recorded. In the histological evaluation, middle-ear epithelia and sub-epithelial space were normal in surfactant-treated ears with OME, whereas mucosal thickening with an oedematous sub-epithelial space containing occasional inflammatory cells and increases in connective tissue and vascularity, and effusions on the epithelial surface were present in the ears with OME in the control group. The significant improvement in the negative middle-ear pressure after nebulized surfactant treatment and the histological findings shown in our study can support the theory that surface-active agents are of importance in eustachian tube function even under pathologic conditions, such as OME.     

Gas exchange function of the middle ear in patients with otitis media with effusion

Gas exchange function through the middle ear mucosa was assessed using nitrous oxide (N₂O) in patients with otitis media with effusion (OME), as well as in normal ears during elective surgery for unrelated disorders. In all normal ears except one (n = 43), an increase in pressure was observed after N₂O inhalation. In 42 of 84 ears with OME, a pressure increase was observed, but not in the remaining 42 ears (50%), indicating that the gas exchange function in these latter ears was impaired. In 21 of the 42 ears showing no middle ear pressure increase following N₂O inhalation, the middle ear pressure was again monitored after myringotomy and aspiration of the effusion A pressure increase was found in 16 ears, indicating that the impairment in gas exchange function in ears with OME may be reversible in most cases. Computed tomography of the mastoid was examined preoperatively in 66 ears, with the presence or absence of a middle ear pressure change well correlated in 57 ears with the presence or absence of mastoid aeration.     

Physiological tympanostomy. A new technique of middle ear ventilation.

Physiological tympanostomy is advanced as a 'substitute' eustachian tube because it opens regularly only on swallowing, as does the 'natural' eustachian tube. The efficacy of the physiological tympanostomy operation was first proved in experimental animals (two dogs). Subsequently, six patients with eustachian insufficiency were successfully managed by this new surgical technique within period of one year, with no post-operative complications. The hearing improved and the middle ears remained air-filled. The method seems to have the following merits: permanent ventilation of the tympanum with preservation of an intact drum (from the functional point of view); no tympanophonia or autophonia; simple technique, short operative period (five minutes); no risk of postoperative complications; and no danger of ascending infection of the middle ear from the ear canal. The demerits appear to be: drainage not ensured; no facility to increase the middle ear pressure by the Valsalva manoeuvre or, Politzerization.     

鼓膜置管治疗鼻咽癌放疗后分泌性中耳炎疗效观察

目的:探讨鼓膜置管对鼻咽癌(NPC)放疗后的分泌性中耳炎(SOM)的疗效。方法:对32例(51耳) NPC放疗后经鼓膜切开抽液冲洗治疗无效的SOM患者进行鼓膜置管和随访,对治疗耳的咽鼓管功能、听力及其 他症状的改变进行评估。结果:随访6个月～5年,治愈8耳,治愈率为15.7%,有效41耳,总有效率为96.1%。 7耳(13.7%)咽鼓管功能好转,所有重复置管耳的耳功能均得到不同程度的改善。置管后耳漏发生率为25.5%, 鼓膜穿孔发生率为9.8%。结论:鼓膜置管治疗SOM有利于咽鼓管功能的恢复,对于咽鼓管功能已经严重损害 的患耳,重复鼓膜置管是维持耳功能的可靠手段;鼓膜置管的并发症利大于弊。     

Middle ear pressures in eustachian tube malfunction: manometric studies

We made direct measurements of the difference in pressure between the middle ear and the ambient atmosphere in 300 ears affected with chronic adhesive otitis media (CAOM), serous otitis media (SOM), and similar disorders of the ear caused by eustachian tube malfunction. We utilized a narrow bore, open U-tube manometer made of No. 205 polyethylene tubing which was connected to a 20 or 22 gauge spinal needle. The needle was passed through the intact tympanic membrane and the displacement of the column of 95 percent alcohol in the manometer was noted and recorded. Our results showed that in 101 ears with CAOM, the average negative pressure difference between the middle ear and the ambient atmosphere was 9 mm 95 percent alcohol, equivalent to 7 mm of H₂O. In 136 ears with SOM, the average negative middle ear pressure was 8 mm 95 percent alcohol, equivalent to 6.5 mm H₂O. In 80 of the 300 diseased ears we tested, the middle and ambient atmospheric pressures were equal. Direct readings of the middle ear pressure tell us the status of the middle ear ventilation at the moment of the measurement.     

Transient inflammation and dysfunction of the eustachian tube secondary to multiple exposures of simulated gastroesophageal refluxant

Gastroesophageal reflux is a common problem in the newborn and preschool periods. Recent research suggests that it may be related to eustachian tube dysfunction and otitis media with effusion. The purpose of this experiment was to investigate the relationship between simulated gastroesophageal reflux and eustachian tube dysfunction. Rat middle ears were repeatedly exposed (transtympanically) to pepsin in hydrochloric acid or to phosphate-buffered saline solution. Their eustachian tube function was evaluated by assessing passive opening and passive closing pressures, and active clearance of positive and negative pressure. The passive pressure function tests showed variable results. The rats exposed to pepsin in hydrochloric acid had an impaired ability to clear positive and negative pressure from the middle ear as compared to the rats exposed only to phosphate-buffered saline solution. The results demonstrate that multiple middle ear exposures to pepsin in hydrochloric acid leads to eustachian tube dysfunction in rats.     

Theoretic analysis of middle ear gas composition under conditions of nonphysiologic ventilation.

As gas flows in and out of the nasopharynx, the pressure in that region fluctuates. It drops below or rises above atmospheric pressure, which is itself not constant but is subject to changes in altitude and weather. Such pressure changes in the nasopharynx produce a pumping of gas into and out of the middle ear. The net amount of middle ear gas transferred from or to the nasopharynx will, component for component, in steady state exactly equal the amount of middle ear gas transferred to or from the microcirculation by means of diffusional absorption by (or release from) the mucosa. In the case of a permanently patulous eustachian tube, a single parameter, characteristic of the rate of ventilation through the open eustachian tube, is found to determine the gas composition in the middle ear, whereas in the case of a middle ear ventilated by tympanostomy, two rate-of-ventilation parameters, one for gas flow through the ventilation tube and one for flow through a periodically open eustachian tube, determine the steady state gas composition. A high rate of ventilation favors absorption of oxygen and venting of carbon dioxide from the middle ear in both cases.     

Alterations of the eustachian tube, middle ear, and nose in rhinovirus infection

This study measured the changes in 64 ears of 32 adult volunteers in eustachian tube function by the nine-step test, middle ear pressure by tympanometry, and nasal patency by active posterior rhinomanometry for 18 days following type 39 or Hanks rhinovirus infection. Abnormal measures were limited to the 75% of subjects (24) with clinical illness (colds) defined by symptom scores. Two days after infection, tubal function was present in only 50% of ears (48) and 20% of persons (5), middle ear underpressures of less than -50 mm H2O were measured in 50% of volunteers (12), and decreased nasal patency was observed in 54% of those with colds (13). These changes resolved 6 to 10 days after challenge. These results support a causal relationship between viral upper respiratory tract infection eustachian tube obstruction and abnormal middle ear pressure.     

Effect of nasal packing on eustachian tube function

Sixty-three patients undergoing surgery to the nasal septum followed by bilateral packing had pre- and post-operative tympanometry in order to determine the effect on eustachian tube function. Fifty-five of the 126 ears tested (46 per cent) developed a reduction in middle ear pressure of at least 50 daPa; 76 per cent became normal within 24 hours of removing the nasal packs. All ears were asymptomatic and no patient had evidence of middle ear effusion. Nasal packing following septal surgery is a frequent cause of short-lasting eustachian tube dysfunction but rarely severe enough to cause symptoms or middle ear effusion. Tubal dysfunction is most likely due to a combination of surgical oedema and a direct effect of the nasal packing.