Prevention of otitis media with effusion by repeated air inflation in a monkey model

OBJECTIVES: To test the following hypotheses that (1) middle ear (ME) air inflation prevents the development of otitis media with effusion in a monkey model of functional eustachian tube obstruction, and (2) ME inflation treatment of otitis media with effusion can cause artifactual clinical improvements due to fluid displacement from the tympanum to the adjacent airspaces. DESIGN: Randomized controlled trial. SUBJECTS: Twelve cynomolgus monkeys. INTERVENTIONS: Eustachian tube dysfunction was induced by botulinum paralysis of the right tensor veli palatini muscle in all monkeys. Before and on study days 9, 15, and 21 after paralysis, the presence or absence, and distribution of ME effusion were documented using magnetic resonance imaging (MRI). Right and left ears were examined twice daily for 21 days using tympanometry, and right ME air inflation (n = 6 ears) or sham inflation (n = 6 ears) was done immediately after those examinations if the ME pressure was -100 mm H2O or less. On 10 of the scheduled MRI evaluations, the MRI was repeated immediately after an inflation to document the possible redistribution of fluid within the ME caused by the maneuver. RESULTS: Middle ear pressure remained within normal limits for the follow-up period in 11 of the 12 nonparalyzed left ears, in none of the 6 sham-inflated right ears, and in 3 of the 6 air-inflated right ears. Three air-inflated right ears developed flat tympanograms (ie, days 14 through 16). Magnetic resonance imaging documented inflammation and fluid in 1 of the 11 nonparalyzed left ears and in all sham-inflated right ears. Lesser degrees of inflammation and effusion based on MRI evaluations were noted for the 3 air-inflated right ears that retained near-ambient pressures when compared with the right 3 ears that developed a flat tympanogram. The MRI measure of effusion quantity within the tympanum was decreased acutely after inflation, but was simultaneously increased in the adjacent airspaces of the temporal bone. CONCLUSIONS: Repeated air inflation prevented the development of otitis media with effusion in 50% of the ears with functional eustachian tube obstruction. Postinflation MRI documented the displacement of fluid by inflation from the tympanum to the mastoid and petrous air cells. Using standard clinical evaluations such as tympanometry and otoscopy, this fluid redistribution can cause a false diagnosis of improvement.     

A Model to Explain the Rapid Pressure Decrease After Air–Inflation of Diseased Middle Ears

Objectives: Air-inflation in humans and monkeys with significant negative middle ear pressure or with middle ear inflammation was shown to cause greater than ambient middle ear pressure initially, followed by a rapid rate of pressure decrease to approach the preinflation value. Study Design: A mathematical model of middle ear pressure regulation is presented and used to simulate air-inflation of the normal and diseased middle ear. Materials and Methods: The model represents the total volume of the middle ear as consisting of three subcompartments representing the airspace, effusion, and mucosa/blood. Gas exchange among those compartments was assumed to be diffusion limited, and the gas exchange between the mucosa/blood compartment and systemic blood was assumed to be perfusion limited. Disease was modeled as an increase in mucosal blood flow or, alternatively, as an increase in the volumes of the effusion and mucosa/blood compartments. Results: The predictions of the model agree better with the experimental data when the increased rate of pressure change after middle ear inflation in diseased ears is driven by an increased volume of the effusion compartment as opposed to an increased perfusion rate. The responsible mechanism is a rapid redistribution among subcompartments of the gas volume introduced into the air compartment. Conclusions: These results suggest that middle ear inflation with inert gas can be used to diagnose the presence and relative amount of middle ear effusion, and that current protocols for treating otitis media with effusion using inflation need to be modified to optimize their intended effect.     

Structural changes in the rat middle ear mucosa due to endotoxin and eustachian tube obstruction

The middle ears of 48 rats were used to examine the effects of endotoxin injection, eustachian tube obstruction or a combination of eustachian tube obstruction and endotoxin injection. Animals were killed after 1, 2, 4, or 12 weeks and the middle ears processed for light and scanning electron microscopy. Compared to the normal middle ear mucosa, the epithelial layer was more pseudostratified, cuboidal or cylindrical after endotoxin injection or obstruction of the eustachian tube. In the early phase, numerous ciliated cells occurred in areas originally almost devoid of these cells. At 3 months, degeneration of ciliated cells was observed. The combination of eustachian tube obstruction and endotoxin injection also induced a more pseudostratified, cuboidal or cylindrical epithelium with an increased number of goblet cells. However, an early decrease occurred in the number of ciliated cells in the tympanic orifice of the eustachian tube. Furthermore, inflammatory cells, mainly PMNs, macrophages and lymphocytes, invaded the subepithelial layer after eustachian tube obstruction and endotoxin injection. These structural changes resulted in an impairment of the mucociliary transport system for clearance of the middle ear cavity. For this reason we believe that both endotoxin and eustachian tube obstruction or dysfunction play an important role in inducing persistent mucosal changes in the middle ear cavity, thereby prolonging otitis media with effusion. Received: 13 February 1998 / Accepted: 4 August 1998     

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.     

The tympano-frontal shunt: A procedure for the treatment of chronic eustachian tube insufficiency.

Eight ears with complications due to chronic eustachian tube insufficiency had insertion of a silicone rubber tympano-frontal shunt tube between the mastoid antrum and the ipsilateral frontal sinus. A one-way valve designed to open at-10 mm H₂O was placed on the tympanic end of the tube to minimize tube obstruction by ear secretions. Follow-up an average of 20 months post insertion showed six of the eight ears to have an aerated middle ear without fluid or tympanic membrane retraction or perforation.     

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。     

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.     

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     

Direct measurement of middle ear pressure through the eustachian tube

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.     

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 dilatation of the eustachian tube during chronic ear surgery

Conclusion: Evaluation of the protympanic segment of the eustachian tube is feasible during chronic ear surgery. Balloon dilatation of that segment yields a bigger aperture. Objective: To evaluate the feasibility of visualization and balloon dilatation of the protympanic segment of the eustachian tube during chronic ear surgery. Methods: This study was carried out on a consecutive case series. All patients undergoing surgical treatment for cholesteatoma or tympanic membrane perforation over a 6-month period of time at a tertiary hospital were evaluated intraoperatively for the ability to visualize the protympanic segment of the eustachian tube, perform balloon dilatation, and then perform visual inspection of the effect of dilatation. Results: A total of 21 chronic ear procedures were performed; visualization of the protympanic segment was feasible in 12 ears, obstruction was identified in 7 ears, and dilatation was undertaken. Immediate assessment showed increased aperture of the tube in all patients when compared with predilatation findings.     

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.     

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.     

Tympanostomy tubes and otic drops

Otic drops have been proposed as a form of prophylaxis against the otitis media which follows middle ear contamination by water in patients with tympanostomy tubes. The potential adverse effects of this form of therapy were studied in chinchillas with tympanostomy tubes; 31 chinchillas underwent bilateral tympanostomy tube insertion. Seven animals had a mixture of green dye and Cortisporin otic suspension placed in both external auditory canals 24 hours following the placement of tympanostomy tubes and were sacrificed 30 minutes later for gross examination; 3 of these animals had previous eustachian tube obstruction with Silastic sponge. Twenty-one animals had Cortisporin otic suspension placed in the right external auditory canal on postoperative days 3, 4, 5, 6 and 7. No otic drops were placed in the left ear. Ten of these 20 animals had VIIIth nerve action potentials measured on postoperative day 17 and the other 11 animals had VIIIth nerve action potentials measured on postoperative day 42 followed by immediate sacrifice for histological examination and scanning electronmicroscopy. The remaining 3 animals had VIIIth nerve action potentials measured 21 days following tympanostomy tube insertion and served as electrophysiological controls. The 8 ears receiving Cortisporin otic drops mixed with green dye from animals with normal eustachian tubes showed staining of the round window membrane at sacrifice, while the 6 ears receiving Cortisporin otic suspension and green dye from animals with eustachian tube obstruction demonstrated no dye in the middle ear. All animals receiving Cortisporin otic drops in the right ear showed an intra-aural difference in action potentials with the right ear being attenuated by an average of 10.3 dB at 2,000 Hz, 12 dB at 4,000 Hz, 21 dB and 8,000 Hz, and 26 dB at 12,000 Hz. Morphological study revealed hair cell loss in the hook portion of the cochlea in those animals receiving Cortisporin otic drops. It was concluded from this study that, in patients with patent tympanostomy tubes in place, potentially ototoxic topical agents should be used with caution.     

Nasal surgery and eustachian tube function: effects on middle ear ventilation

Objectives: To investigate the effect of nasal obstruction surgery on eustachian tube function and middle ear ventilation. Design: Prospective study. Setting: University Campus Bio‐Medico of Rome. Participants: Forty consecutive patients who underwent nasal surgery were evaluated for middle ear ventilation and tubal function. Main outcome measures: Pre‐ and postoperative Valsalva and Toynbee tubal function tests, tympanometry and ear fullness sensation were evaluated for both ears of each patient. Results: Results of postoperative tubal function tests were significantly better than preoperative ones (90% versus 46%; P < 0.001). No significant difference in tympanometric values was found. The majority (95%) of the patients reported a postoperative improvement of ear fullness sensation compared with preoperative (25%; P < 0.001). Conclusions: Surgery for chronic nasal obstruction significantly improves clinical tubal function but 1‐month postoperative tympanometric findings remain almost the same.     

Effects of ciprofloxacin-dexamethasone on myringotomy wound healing

OBJECTIVE: To evaluate the effects of the ciprofloxacin-dexamethasone (CDX) combination ototopical treatment after myringotomy on tympanic membrane (TM) healing in ears with eustachian tube obstruction (ETO) and unobstructed ears. STUDY DESIGN: Prospective, randomized, masked, controlled. METHODS: ETO was created in the left ear of 30 rats to induce a model of otitis media with effusion (OME). After 3 weeks, bilateral myringotomy was performed (day 0). Animals were randomized into three groups to receive no treatment or bilateral once daily ototopical treatment with balanced salt solution (BSS, vehicle) or CDX for 13 days. Bilateral otomicroscopy was performed on days 7, 14, and 28. On day 14, five randomly selected animals per group were humanely euthanized and the TM harvested for histology. Three additional rats provided normal negative control ears for histologic comparisons. RESULTS: On day 14, TM perforation healing rates were 100% in all ears of untreated and BSS-treated animals, 89% (8/9) in CDX-treated obstructed ears, and 30% (3/10) in CDX-treated unobstructed ears (P < .05 vs. BSS). On day 28, 100% (5/5) of the CDX-treated unobstructed ears and 80% (4/5) of the CDX-treated obstructed ears were healed. Histology showed initial TM thickening postmyringotomy in all ears but no significant qualitative differences between groups on day 28. CONCLUSION: Myringotomy healing was transiently modulated by treatment with CDX but proceeded normally after CDX discontinuation. This early modulation might enhance middle ear drainage and middle ear concentrations of CDX when tympanostomy tube surgery is performed in patients with active OME and ETO, thus potentially reducing otorrhea and preventing or treating infection. It would not be expected to increase the risk of premature tube extrusion or adversely affect normal healing of the TM after usual spontaneous extrusion.     

Mechanical obstruction of the eustachian tube by the benign tumor of the parapharyngeal space does not cause otitis media with effusion.

OBJECTIVE: We are reporting on eustachian tube and middle ear pathologic findings in patients with parapharyngeal tumors. PATIENTS: Eleven cases of eustachian tube involvement as indicated by obstruction due to compression of the tumor were assessed in this study. MAIN OUTCOME MEASURES: Each patient underwent otoscopy, nasopharyngoscopy, a pure-tone hearing test, impedance audiometry, and sonotubometry. RESULTS: All of the tumors were diagnosed benign according to the histologic examination. In 9 of the 11 patients, the pharyngeal opening of the eustachian tube narrowed or was blocked by the tumor. None of the patients showed any response on the tumor side in the sonotubometry. Therefore, gas exchange was prevented through the eustachian tube by the tumor; however, they also showed an intact tympanic membrane and normal hearing tests. CONCLUSION: According to our data, if there is drainage of middle ear fluid through the eustachian tube and the exchange of gas in the middle ear is preserved, otitis media with effusion will not occur even in cases such as these.     

The old-fashioned Politzer maneuver: a video clip demonstration

Politzer maneuver causes retrograde inflation of the middle ear by forcing air through the eustachian tube, and it has been proposed by many authors as the main nonsurgical treatment of middle ear effusion. To our knowledge, this is the first case in the literature in which air entering into a middle ear with effusion through a Politzer maneuver has been captured on video (www.laryngoscope.com).     

Laser eustachian tuboplasty: a preliminary report

OBJECTIVES/HYPOTHESIS: Surgical correction of eustachian tube dysfunction remains an elusive challenge. Repeat ventilation tube placement is often inadequate to prevent tympanic membrane and middle ear complications. Endoscopic analyses of eustachian tube dynamics have localized the site of primary pathophysiology to within the cartilaginous tube. The study investigated the feasibility, safety, and efficacy of a new endoluminal eustachian tube operation for the treatment of eustachian tube dysfunction. STUDY DESIGN: Prospective, institutional review board-approved surgical trial in a tertiary-care medical center. METHODS: Ten patients with more than 5 consecutive years of intractable otitis media with effusion recurring after two or more tympanostomy tube placements were treated with unilateral laser eustachian tuboplasty. Surgery was performed on an outpatient basis with the use of general anesthesia and combined both transnasal and transoral approaches. A 980-nm diode or argon laser was used to vaporize an appropriate amount of mucosa and cartilage on the posterior wall of the tubal lumen. Preoperative and postoperative dynamic video eustachian tube function analyses were compared. Outcome measures were presence or absence of middle ear effusion and impedance tympanograms. RESULTS: Five patients had at least 12 months of follow-up, and three of them had absence of any effusion (60%). Two patients had recurrence of their otitis media with effusion and required tympanostomy tubes again. Five patients had at least 6 months of follow-up, and four of them had absence of any effusion. The remaining patient had recurrence of otitis media with effusion and received a tympanostomy tube again. Overall results for all 10 patients after 6 months were 7 free of effusion (70%). There were no intraoperative complications. Postoperative complications were limited to minimal peritubal adhesions and one intranasal synechia. CONCLUSIONS: Preliminary results suggest that laser eustachian tuboplasty is safe and efficacious in the treatment of intractable eustachian tube dysfunction. Further study will be necessary to determine whether laser eustachian tuboplasty is a suitable alternative to repeated tympanostomy tube placement in selected patients.     

A comparative study on efficiency of middle ear pressure equalization techniques in healthy volunteers

Objective

To compare success rates of middle ear inflation device (Ear Popper ^©), Valsalva maneuver and Toynbee maneuver in middle ear pressure equalization in healthy adults.

Materials and methods

Adult volunteers with otoscopically healthy ears were enrolled to the study. In a prospective setting, 60 ears of 35 volunteers were divided into two groups according to eustachian tube (ET) functions tested using the nine step inflation deflation test. Group A: good eustachian tube function at nine step inflation deflation test (30 ears), Group B: possible dysfunction of the ET at nine step inflation deflation test (30 ears). All the volunteers performed Valsalva maneuver, Toynbee maneuver and Ear Popper^© application, respectively. The efficiencies of all the three techniques were statistically compared first overall, then paired-wise between the two groups.

Results

There was no statistical difference in success rates of middle ear pressure equalization techniques in 60 ears, regardless of ET function results (Valsalva and Toynbee maneuvers 51.7% effective, Ear Popper^© 43.3% effective). There was also no statistical difference among the middle ear pressure shifts obtained by these three techniques. In almost half of the subjects in whom at least one technique was unsuccessful, the other two was effective. When the groups were separately compared; there was no significant difference between Valsalva and Toynbee maneuvers, whereas Ear Popper^© was found more effective in Group A (56.7% vs. 30%, p = 0.037).

Conclusion

No statistical difference in equalization of the middle ear pressure was found among Valsalva maneuvers, Toynbee maneuvers and Ear Popper^© in healthy adults under physiological conditions. Using alternative techniques may improve the success individually when a technique fails.