€ der, S.,* Lehmann, M.,* Korbmacher, D.,* Sauzet, O.,† Sudhoff, H.* & Ebmeyer, J.* Schro *
Department of Otorhinolaryngology, Head and Neck Surgery, Klinikum Bielefeld, Academic Teaching Hospital University of M€ unster, Epidemiology and International Public Health, School of Public health, Bielefeld University, Bielefeld, Germany
†
Accepted for publication 21 April 2015 Clin. Otolaryngol. 2015, 40, 691–697
Objective: The objective of this study was to demonstrate the reliability of tubomanometry (TMM) described by Esteve in the diagnosis of chronic obstructive Eustachian tube (ET) dysfunction. Study design: Combined prospective and retrospective clinical study. Setting: Tertiary referral centre, affiliated to university. Methods: Two hundred and fifteen healthy subjects were examined once, 25 healthy subjects underwent TMM weekly for 6 weeks, and six healthy subjects were tested three times a day on at least three different days. The results of tubomanometry in healthy subjects were compared to data obtained from 171 patients with chronic obstructive ET dysfunction. Results: In healthy subjects, there was an immediate opening of the ET at 30–50 mbar with an R-value ≤1 in at least 94% of the cases. In patients with chronic ET dysfunction, an opening of the ET could be registered in only 42% of patients at 30 mbar and in 58% at 50 mbar. The average of the R-value in these subjects always indicated
towards a delayed opening (R > 1). When measurements are repeated in the same subject with a weekly interval, the intraclass correlation (ICC) was 0.49 for the TMM with 30 mbar, 0.51 for the TMM with 40 mbar and 0.52 for the TMM with 50 mbar in healthy people. For the patients with symptoms of ET dysfunction, the ICC for up to four repeated measures was 0.50 for the TMM with 30 mbar, 0.53 for the TMM with 40 mbar and 0.54 for the TMM with 50 mbar. A complete agreement of the results in repeated measurements within seconds was present in 86% for 30 and 40 mbar and in 79% for 50 mbar. The ICC was 0.61 for the TMM with 50 mbar, 0.62 for the TMM with 40 mbar and 0.68 for the TMM with 30 mbar. Conclusions: Tubomanometry can support the diagnosis of ET dysfunction. An R-value ≤1 indicates a regular function of the ET, an R-value >1 indicates a delayed opening of the ET, and no definable R-value means no detectable opening of the ET. TMM is a reliable and valid instrument to support the diagnosis of chronic obstructive ET dysfunction.
The significance of the Eustachian tube (ET) in the pathophysiology of the middle ear is beyond controversy. This is the reason why the dysfunction of the ET moved into the focus of medical research in recent years. The ET is responsible for pressure equilibration in the middle ear. It consists of a bony part comprising the lateral one-third of the canal starting in the middle ear and a cartilaginous part comprising the medial two-thirds ending in the epipharynx.1,2 Under normal conditions, the cartilaginous part of the ET is closed and opens briefly for about 200 ms during swallowing, chewing, yawning or other jaw movements. Obstruction of the ET is a very common disorder that is not only uncomfortable but may also result in chronic otitis
media, retractions of the tympanic membrane and even cholesteatoma. Otologists generally agree that ET function is critical for the outcome of middle ear surgery.3,4 Typical symptoms of ET dysfunction are a feeling of pressure in the ears intensifying with changes of the atmospheric pressure and the inability to successfully perform Valsalva manoeuvre. Both chronic obstructive ET dysfunction and patulous ET can lead to similar complaints. It might be challenging to differentiate between these diagnoses. There is a lack of reliable diagnostic tools and effective therapeutic approaches for ET dysfunction.5 Otomicroscopic evaluation of the tympanic membrane, Valsalva and Toynbee manoeuvre and pneumatic otoscopy are easily conducted but do not necessarily deliver reliable and quantifiable results. In clinical practice, usually a combination of the different available diagnostic tests is used. Other tests like impedance testing in the pressure chamber require expensive equipment but do not yield any unique
Correspondence: Dr. med. S. Schr€ oder, Department of Otorhinolaryngology, Head and Neck surgery, Klinikum Bielefeld, Teutoburger Str. 50, 33604 Bielefeld, Germany. Tel.: +49 521 581 3301; Fax: +49 521 581 3399; e-mail: [email protected] © 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
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ORIGINAL ARTICLE
Evaluation of tubomanometry as a routine diagnostic tool for chronic obstructive Eustachian tube dysfunction
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information. Additionally, most of these tests require an intact tympanic membrane. MRI of the ET and video endoscopy and sonotubometry have not proven to be suitable for daily clinical practice so far.6–8 Tubomanometry (TMM) was first described by Esteve in 2001.9,10 It allows assessment of ET function under defined conditions: swallowing a sip of water triggers the release of a defined pressure (e.g. 30, 40 and 50 mbar) through a nasal applicator. A pressure probe in the external auditory canal registers pressure changes transmitted through movements of the tympanic membrane or through a perforation in the tympanic membrane. Thus, TMM is a semi-objective method to record ET function. As there is no gold standard for the objective assessment of Eustachian tube function and tympanometry alone did not seem sufficient for the evaluation of Eustachian tube function, we started using the TMM in daily routine. So far, there is only little literature on the validity and reliability of this diagnostic device. The purpose of this study was to analyse our own data regarding reliability and validity of TMM. Methods Tubomanometry
Tubomanometry (TMM) was initially produced by La Diffusion Technique Francaise in Saint-Etienne, France, and is now available via Spiggle & Theis in Overath, Germany. The principle of TMM is to deliver defined pressures of 30, 40 and 50 mbar to the epipharynx through a nasal applicator. Swallowing triggers the opening of the cartilaginous part of the ET and at the same time temporarily seals the epipharynx towards the pharynx. A pressure receptor probe sealing the external ear canal registers pressure changes transmitted through movements of the tympanic membrane or even through a perforation in the tympanic membrane. If the ET opens during swallowing, the defined pressure applied to the epipharynx is transmitted to the middle ear. Pressure curves of the epipharynx and the ear canal are displayed on the monitor of the TMM device, and various measuring values are calculated (Fig. 1). Diagrams are created to measure the pressure changes in nasopharynx and ear canal in mbar against the time in seconds (Fig. 2). The opening latency index (R-value) reflects the latency between pressure application in the epipharynx and measurement of a pressure change in the ear canal (R = P1–C1/C2–C1). P1 represents the start of the movement of the eardrum or the pressure increase in the ear canal, respectively, after pressure application. C1 represents the start of the pressure increase in the nasopharynx, and C2 pinpoints the maximum pressure increase in the nasopharynx. Thus, the opening latency index
Fig. 1. Performance of the tubomanometry by Esteve.
quantifies ET function: an immediate opening (R < 1) indicates normal ET function and a late opening (R ≥ 1) indicates restricted ET function. No opening (R negative or not measurable) indicates complete obstruction of the ET.9,10 In patients with patulous ET, the opening is always immediate. In some cases of patulous ET, fluctuations of the pressure in the outer ear canal can be observed after pressure application in the nose (Fig. 2c). TMM is a semi-objective method to record and to some extent quantify ET function. It is not uncomfortable for the patient as well as being quick and easy to perform. Patients
Tubomanometry (TMM) has been used routinely in our department since 2009 on all patients with suspicion of ET dysfunction. We recommend a pressure set-up of 30, 40 and 50 mbar for routine testing. An immediate opening of the ET (R ≤ 1) is rated as normal function, delayed opening (R > 1) hints towards an impaired function, and no opening (negative or not measurable R) means complete obstruction of the ET. Between August and October 2011, 215 healthy subjects (430 ears) underwent TMM once, 25 healthy subjects (50 ears) were examined in weekly intervals for 6 weeks and six healthy subjects (12 ears) were examined three times a day on at least three different days. All subjects underwent physical examination, history, tympanometry, audiometry and tubomanometry. The healthy subjects were volunteers without history of ear diseases or ear surgery and normal eardrums on microscopic examination. In healthy subjects, there were no patients with acute and chronic sinusitis. We compared our results in healthy subjects to our data obtained from 171 patients (342 ears) with chronic obstructive ET dysfunction collected between 2009 and 2012. These patients had a curve type B/C tympanogram and/or recurrent otitis media with effusion in the past 2 years and/or © 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
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(a)
(b)
693
(c)
Fig. 2. Tubomanometry (TMM) by Esteve: Pressure curves of the epipharynx and the ear canal. (a) immediate opening (R < 1) indicating normal ET function (b) no opening (not measurable) indicating obstruction of the ET (c) patulous ET with fluctuation of the pressure curve in the ear canal.
subjectively and objectively negative Valsalva. To evaluate reproducibility and reliability, we used data from 11 healthy subjects (22 ears) and 59 patients (118 ears) with chronic obstructive ET dysfunction undergoing repeated measurements with at least 1 week of time in between measurements. In the group of patients with chronic obstructive ET dysfunction, nine patients had previous surgery of the paranasal sinuses but no active signs of disease. The mean age in the 215 healthy subjects was 46 years, and 66.5% were female and 33.5% were male. The mean age in the 171 patients with chronic obstructive Eustachian tube dysfunction was 50 years, and 45% were female and 55% were male. All subjects gave informed consent to the use of all collected data for clinical research and agreed with the participation. Additionally, the findings of 100 tubomanometries were analysed by three experienced otologists independently to evaluate the objectivity of this method, and for the reproducibility, we performed for every pressure three repeated measurements within seconds in 14 ears. All results of the TMM were encoded for the evaluation. An R ≤ 1 was encoded with two points, an R > 1 with 1 point and no R-value with 0 points. Statistical analysis
The inter-rater reliability was tested using intraclass correlation (ICC) which was obtained using mixed models (Stata function xtmixed) for each pressure, separately assuming the independence of the two ears on the same patient. Results
Among the healthy subjects, a constant positive Valsalva was reported for 382 ears (88.8%) and only sometimes positive Valsalva for 28 ears (7.6%) and a negative Valsalva for 10 ears © 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
(3.6%). In 240 ears (55.8%), the Toynbee was always positive; in 58 ears (13.5%) sometimes Toynbee was positive and in 132 ears (30.7%) the Toynbee was negative. Overall, 427 ears were tested in audiometry. Age-related normal findings were obtained in 302 ears (70.7%). The microscopy of the eardrum showed normal findings in all healthy subjects included in the trial, and the objective Valsalva was positive in 82.9% and negative in 17.1% of the ears. 425 of 428 examined ears showed a type A and three ears a type B tympanogram. In the group of patients with chronic obstructive ET dysfunction, the objective Valsalva was positive in 37.4% and negative in 62.6% of the ears. Only 9.1% showed a type A tympanogram, 64.9% a type B and 26% of the ears a type C. The findings of the tympanic membrane in all patients with chronic obstructive ET dysfunction are shown in Table 1. The Tables 2 and 3 demonstrate the results of tubomanometry (TMM) in healthy subjects and patients with chronic ET dysfunction. In healthy subjects, an opening of the ET could be determined in at least 94% at 30–50 mbar and the average R-value always hinted towards an immediate opening (R ≤ 1) in 30. However, the patients with chronic ET dysfunction had an opening of the ET in only 42% at 30 mbar and in 58% at 50 mbar. The average R-value revealed that it was always a delayed opening (R > 1). Not more than 45% of the ears in the ET dysfunction group had an immediate opening of the ET at 30–50 mbar. The range of the R-value in the group of healthy subjects with repeated testing over several weeks was ≤0.99 in 68% and ≤1.99 in 92%. This means the deviations were quite low. Among the patients with chronic obstructive ET dysfunction, 63% (47 of 75) had no R-value at 30 mbar in all measurements and 10% (8 of 75) had an R-value >1 in all measurements with ranges up to 3.45. All other patients had a mixture of opening and no opening of the ET.
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Table 1. Findings of the tympanic membrane in patients with chronic obstructive ET dysfunction
Total number of ears Per cent Valsalva negative Tympanometry Jerger type R-value 50 mbar
Normal findings
Effusion middle ear
Recurrent Effusion
Adhesive process
Cholesteatoma
Retraction
Perforation
192 56.1% 53.5% A: 9.2% B: 51.3% C: 41% ≤1: 26.8% >1: 32.8% No: 40.4%
40 11.7% 76.7% A: 9.3% B: 88.4% C: 2.3% ≤1: 23.3% >1: 32.6% No: 44.2%
27 7.9% 84% A: 12% B: 76% C: 12% ≤1: 20% >1: 28% No: 52%
26 7.6% 82.1% A: 7.1% B: 89.3% C: 3.6% ≤1: 22.1% >1: 29.6% No: 48.1%
9 2.6% 90% A: 20% B: 80% C: 0% ≤1: 50% >1: 20% No: 30%
42 12.3% 53.7% A: 12.5% B: 85% C: 2.5% ≤1: 24.4% >1: 34.1% No: 41.5%
6 1.8% 100% A: 0% B: 100% C: 0% ≤1: 50% >1: 16.7% No: 33.3%
Table 2. Results of the tubomanometry in healthy subjects and patients with chronic obstructive Eustachian tube (ET) dysfunction Chronic obstructive Eustachian tube dysfunction
Healthy subjects
Amount
Opening of the ET No opening of the ET Mean R-value Standard Deviation Minimum R-value Maximum R-value R-value 0.01–1
30 mbar
40 mbar
50 mbar
30 mbar
40 mbar
50 mbar
404 (94%) 26 (6%) 0.83 0.87 0.01 7.62 77.5%
416 (97%) 14 (3%) 0.78 0.74 0.01 7.65 75.2%
418 (97%) 12 (3%) 0.78 1.20 0.01 18.16 82.1%
142 (42%) 200 (58%) 2.43 3.35 0.01 19.00 43%
155 (45%) 187 (55%) 2.41 4.01 0.01 30.42 45.2%
197 (58%) 145 (42%) 2.06 3.21 0.04 30.42 45.7%
Table 3. Results of the tubomanometry using the R-value categories in % Healthy subjects
Chronic obstructive ET dysfunction
R-value
30 mbar
40 mbar
50 mbar
30 mbar
40 mbar
50 mbar
≤1 >1 No R
73 21 6
73 24 3
79.8 17.2 3
18 24 58
20 25 55
26.3 31.7 42
When measurements are repeated in the same healthy subject with a weekly interval for up to six times, the intraclass correlation (ICC) was 0.49 for the TMM with 30 mbar, 0.51 for the TMM with 40 mbar and 0.52 for the TMM with 50 mbar. For the patients with symptoms of ET dysfunction, the ICC for up to four repeated measures with at least a weekly interval was 0.50 for the TMM with 30 mbar, 0.53 for the TMM with 40 mbar and 0.54 for the TMM with 50 mbar. In the three (up to six) times daily measurements, there were no significant fluctuations. The range of the R-value over the day was ≤0.6 with two outliers, and the range of the ET score over the day was ≤1 with one outlier. For TMM with 50 mbar, 38 of 44 measures were in complete agreement, 32 of 44 for the TMM with 40 mbar and 31/44 for the TMM with 30 mbar.
We performed three repeated measurements of the TMM within seconds in 14 healthy persons for 30, 40 and 50 mbar. A complete agreement of the results in the repeated measurements was present in 86% for 30 and 40 mbar and in 79% for 50 mbar. The maximum deviation of the absolute R-value was 2.75 for 30 mbar, 0.96 for 40 mbar and 2.4 for 50 mbar. The ICC was 0.61 for the TMM with 50 mbar, 0.62 for the TMM with 40 mbar and 0.68 for the TMM with 30 mbar. Additionally, 100 randomly selected TMM findings were analysed by three experienced otologists independently to investigate reliability of the results. Inter-rater reliability measures in terms of ICC ranged from 0.83 to 0.90 between the three different pressures (30–50 mbar) with overall 85% of complete agreement between the three raters. Complete results are given in Table 4. There were two cases of non© 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
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adjacent disagreement, and there were no cases of complete disagreement. Discussion
Chronic obstructive dysfunction of the Eustachian tube moved into increased focus of otologists in the past decades. It is acknowledged that Eustachian tube function has a major impact on the healing process after middle ear surgery and plays an important role in the development of otitis media with effusion and cholesteatoma. There is no gold standard for the diagnostic of disorders of the ET. When we started balloon Eustachian tuboplasty (BET) in 2009, we were confronted with the lack of sufficient diagnostic tools for the assessment of chronic ET dysfunction. Most important for the indication of BET are patient history and complaints. In 2012, McCoul et al.11 developed the ETDQ-7, a new instrument to facilitate the collection of clinical data concerning ET function. Our own investigations indicate that the ETDQ-7 is a well reproducible and valid instrument to clinically assess ET function.12 But it is only focused on the subjective complaints of the patients and it does not include any objective data. More objective data can be obtained by the examination of eardrum and nasopharynx. Chronic otitis media with effusion and an adhesive or atelectatic tympanic membrane point to the diagnosis of chronic obstructive ET dysfunction. For this reason, we stared to include Esteve’s tubomanometry into our regular workup of patients with symptoms of ET dysfunction. TMM is easy to perform and a complete examination of both ears takes only about 5 min in the hands of an experienced technician. Another distinct advantage of TMM is that it works in intact as well as perforated eardrums. In our first investigations of tubomanometry in 2009, we found a significant correlation between the results of different investigators and different times of investigation.13 Esteve compared the results of TMM in 58 healthy subjects and 56 patients with chronic otitis media. He described no significant intra-individual variations of the R-parameter. In 67% of healthy subjects, R was ≤1, in 26%, R was >1, and in 7% of healthy subjects, no opening of the ET was observed. In the cohort with chronic otitis media, 13% had an R ≤ 1, 38% had an R > 1, and 51% had no opening of the ET at all.9,10 Table 4. Inter-rater reliability over 34 ears tested by three raters TMM measurement
ICC (95% CI)
Percentage complete agreement
30 mbar 40 mbar 50 mbar
0.90 (0.84, 0.95) 0.83 (0.73, 0.91) 0.87 (0.79, 0.93)
85% (29/34) 70% (24/34) 85% (29/34)
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This data correspond with our results. Esteve believes that the TMM measures not only the function of the ET but also the whole transfer of gas by the ET and the mucosa of the mastoid. Esteve also extracts other helpful information about the middle ear from TMM. For example, can a P2-P1 larger than 0.9 mbar indicate a retraction pocket or an atrophy of the tympanic membrane.10 There are some alternatives to obtain at least semiobjective data on ET function. The clinical examination with Valsalva and Toynbee manoeuvre are daily routine. Both are good indicators for the consistency of the ET but not necessary for the normal function. The opening of the ET can be visible by movements of the tympanic membrane, but might be too weak or rare for normal function. The standard test for the evaluation of the pressure conditions behind the tympanic membrane and indirectly for the function of the ET is tympanometry. It is easy and fast to perform and available to each otologist. More detailed information about ET function is offered by the nine step inflation–deflation test.14 However, this test requires an intact tympanic membrane and is complex and time-consuming. Sonotubometry with perfect sequences (PSEQ) like TMM is employable not only in patients with intact but also perforated eardrums. For sonotubometry, a microphone is placed in the external auditory canal and a loudspeaker in the ipsilateral nostril. The transmission of a continuous tone via the ET into the external auditory canal is recorded. Alterations in the recorded frequencies can be correlated to ET function. Sonotubometry is supposed to be able to detect Eustachian tube openings in both normal and pathological ears.15 Another promising concept is the tensometry with stretch marks on the ear drum. A so far only experimental study could in the future lead to an approach offering long-term measurements of the movements of the ear drum.16 For investigation of the ET with medical imaging, CT and MRI of the temporal bone are important. In recent years, for example, functional MR imaging of the ET was introduced. It is supposed to visualise ET opening during Valsalva manoeuvre.17 Another new approach is the Valsalva CT or special CT sequences during swallowing.18 All of these examinations share of course the disadvantage that they are complex, costly and partly expose the patient to irradiation. The amount of diagnostic approaches to ET function demonstrates that there is a huge interest and a need for reliable diagnostic tools. Most of the recently developed techniques are not used in daily routines. The reason is the missing proof of their functionality, reliability and validity. On the other hand, some are too expensive or not practical in daily routine. Tubomanometry is easy to perform and quickly evaluated. In particular, in combination with other
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clinical tests, it offers promising results. However, the analysis of the results requires some experience. Setting the points to calculate the R-value is critical. A standardised setting to perform the measurement is also essential. The pressure receptor needs to be adjusted, so that it is airtight in the ear canal. Otherwise, measurements might be false negative. We recommend bilateral measurements even if the patient has only unilateral complaints because the intraaural comparison might facilitate the analysis. For example, the ear without complaints might show an immediate opening (R ≤ 1) at 30–50 mbar. The other ear with might only show a delayed opening (R < 1) at 30–50 mbar. This could support the subjective feeling of the patient that the ET of one side works less. We recommend to always measure 30, 40 and 50 mbar in each patient. This can indicate towards the severity of the dysfunction. In patients only suffering from complaints during diving or flights, the measurement at 50 or 40 mbar might be normal (R ≤ 1) but a lower pressure set-up might reveal a delayed opening or no opening, for example, at 30 mbar. Concerning our results in the repeated measurements and the corresponding ICCs, it is hard to say what the reasons for the deviations in the measurements are. On the one hand, the function of the ET might be subject to daily or weekly fluctuations. Thus, TMM can only give a snapshot view on ET function. On the other hand, there might be uncertainties in TMM itself. It seems desirable to improve the accuracy of the receptors and to try to implement measurements without additional pressure. This means objectifying the Valsalva manoeuvre. The cut-off points of the R-value were suggested by Esteve and co-workers. The accuracy of these values should be further investigated. For the assessment of ET function, it might be sufficient to distinguish between a visible R-value and no visible opening of the ET. However, TMM can be considered a useful additional diagnostic tool in patients with chronic obstructive ET dysfunction. It should not be used as the only instrument for diagnosing diseases of the ET but as an additional semi-objective tool. We use the TMM as the more objective part of the ETS-7 (Eustachian tube score) for the evaluation of ET function.19 In particular, due to its suitability for daily routine, tubomanometry is worth refining. Conclusion
Tubomanometry (TMM) can support the diagnosis of a dysfunction of the ET. An R-value ≤1 indicates a normal ET function, an R-value >1 indicates a delayed opening of the ET, and no definable R-value means no opening of the ET. TMM is a reliable and valid instrument to support the diagnosis of chronic obstructive ET dysfunction.
Keypoints
• •
The Tubomanometry is an additional diagnostic tool to evaluate the Eustachian tube function. The R-value seems to be a good indicator.
Reference 1 McCoul E.D., Lucente F.E. & Anand V.K. (2011) Evolution of Eustachian tube surgery. Laryngoscope 121, 661–666 2 Leuwer R. & Koch U. (1999) Anatomy and physiology of the auditory tube. Therapeutic possibilities in chronic disorders of tubal function. HNO 47, 514–523 3 Podoshin L., Fradis M., Malatskey S. et al. (1996) Tympanoplasty in adults: a five-year survey. Ear Nose Throat J. 75, 149–52, 55-6 4 Dorrie A., Dommerich S. & Pau H.W. (2003) Early postoperative middle-ear ventilation – risk for the transplant or guarantee for aeration of the tympanic cavity? Laryngorhinootologie 82, 102–104 5 Todd N.W. (2000) There are no accurate tests for eustachian tube function. Arch. Otolaryngol. Head Neck Surg. 126, 1041–1042 6 Poe D.S., Grimmer J.F. & Metson R. (2007) Laser eustachian tuboplasty: two-year results. Laryngoscope 117, 231–237 7 Pau H.W. (2011) Eustachian tube and middle ear mechanics. HNO 59, 953–963 8 Di Martino E.F.N. (2013) Eustachian tube function tests. An update. HNO 61, 467–476 9 Esteve D., Dubreuil C., Della Vedova C. et al. (2001) Evaluation par tubomanometrie de la fonction d’ouverture tubaire et de la reponse tympanique chez le sujet normal et chez le sujet porteur d’une otite sero-muqueuse chronique: comparaison des resultats. J Fr Orl 50, 223–231 10 Esteve D. (2003) Tubomanometry and pathology. In Fibrocartilaginous eustachian tube. Middle ear cleft, Ars B. A. (ed.) pp. 159–175. Kugler Publications, The Hague. 11 McCoul E.D., Anand V.K. & Christos P.J. (2012) Validating the clinical assessment of eustachian tube dysfunction: the Eustachian Tube Dysfunction Questionnaire (ETDQ-7). Laryngoscope 122, 1137–1141 12 Schr€ oder S., Lehmann M., Sudhoff H. et al. (2014) Assessment of chronic obstructive eustachian tube dysfunction: Evaluation of the German version of the Eustachian Tube Dysfunction Questionnaire. HNO 62, 162–164 13 Sudhoff H., Ockermann T., Mikolajczyk R. et al. (2009) Clinical and experimental considerations for evaluation of Eustachian tube physiology. HNO 57, 428–435 14 Bluestone C.D.. Eustachian tube. Structure, function, role in otitis media. BC Decker, Hamilton, London, S 127–S 130. 15 Asenov D.R., Nath V., Telle A. et al. (2010) Sonotubometry with perfect sequences: first results in pathological ears. Acta Otolaryngol. 130, 1242–1248 16 Zehlicke T., Just T., Punke C. et al. (2011) Optotensometry for measuring the tube function – a feasibility study on a middle ear model. Laryngorhinootologie 90, 276–281
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17 L€ ukens A., Dimartino E., G€ unther R.W. et al. (2012) Functional MR imaging of the eustachian tube in patients with clinically proven dysfunction: correlation with lesions detected on MR images. Eur. Radiol. 22, 533–538 18 McDonald M.H., Hoffman M.R., Gentry L.R. et al. (2012) New insights into mechanism of Eustachian tube ventilation based on
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cine computed tomography images. Eur. Arch. Otorhinolaryngol. 269, 1901–1907 19 Schr€ oder S., Lehmann M., Sauzet O. et al. (2015) A novel diagnostic tool for chronic obstructive Eustachian tube dysfunction -The Eustachian Tube Score. Laryngoscope 125, 703–708
Department of Otorhinolaryngology, Head and Neck Surgery, Klinikum Bielefeld, Academic Teaching Hospital University of M€ unster, Epidemiology and International Public Health, School of Public health, Bielefeld University, Bielefeld, Germany
†
Accepted for publication 21 April 2015 Clin. Otolaryngol. 2015, 40, 691–697
Objective: The objective of this study was to demonstrate the reliability of tubomanometry (TMM) described by Esteve in the diagnosis of chronic obstructive Eustachian tube (ET) dysfunction. Study design: Combined prospective and retrospective clinical study. Setting: Tertiary referral centre, affiliated to university. Methods: Two hundred and fifteen healthy subjects were examined once, 25 healthy subjects underwent TMM weekly for 6 weeks, and six healthy subjects were tested three times a day on at least three different days. The results of tubomanometry in healthy subjects were compared to data obtained from 171 patients with chronic obstructive ET dysfunction. Results: In healthy subjects, there was an immediate opening of the ET at 30–50 mbar with an R-value ≤1 in at least 94% of the cases. In patients with chronic ET dysfunction, an opening of the ET could be registered in only 42% of patients at 30 mbar and in 58% at 50 mbar. The average of the R-value in these subjects always indicated
towards a delayed opening (R > 1). When measurements are repeated in the same subject with a weekly interval, the intraclass correlation (ICC) was 0.49 for the TMM with 30 mbar, 0.51 for the TMM with 40 mbar and 0.52 for the TMM with 50 mbar in healthy people. For the patients with symptoms of ET dysfunction, the ICC for up to four repeated measures was 0.50 for the TMM with 30 mbar, 0.53 for the TMM with 40 mbar and 0.54 for the TMM with 50 mbar. A complete agreement of the results in repeated measurements within seconds was present in 86% for 30 and 40 mbar and in 79% for 50 mbar. The ICC was 0.61 for the TMM with 50 mbar, 0.62 for the TMM with 40 mbar and 0.68 for the TMM with 30 mbar. Conclusions: Tubomanometry can support the diagnosis of ET dysfunction. An R-value ≤1 indicates a regular function of the ET, an R-value >1 indicates a delayed opening of the ET, and no definable R-value means no detectable opening of the ET. TMM is a reliable and valid instrument to support the diagnosis of chronic obstructive ET dysfunction.
The significance of the Eustachian tube (ET) in the pathophysiology of the middle ear is beyond controversy. This is the reason why the dysfunction of the ET moved into the focus of medical research in recent years. The ET is responsible for pressure equilibration in the middle ear. It consists of a bony part comprising the lateral one-third of the canal starting in the middle ear and a cartilaginous part comprising the medial two-thirds ending in the epipharynx.1,2 Under normal conditions, the cartilaginous part of the ET is closed and opens briefly for about 200 ms during swallowing, chewing, yawning or other jaw movements. Obstruction of the ET is a very common disorder that is not only uncomfortable but may also result in chronic otitis
media, retractions of the tympanic membrane and even cholesteatoma. Otologists generally agree that ET function is critical for the outcome of middle ear surgery.3,4 Typical symptoms of ET dysfunction are a feeling of pressure in the ears intensifying with changes of the atmospheric pressure and the inability to successfully perform Valsalva manoeuvre. Both chronic obstructive ET dysfunction and patulous ET can lead to similar complaints. It might be challenging to differentiate between these diagnoses. There is a lack of reliable diagnostic tools and effective therapeutic approaches for ET dysfunction.5 Otomicroscopic evaluation of the tympanic membrane, Valsalva and Toynbee manoeuvre and pneumatic otoscopy are easily conducted but do not necessarily deliver reliable and quantifiable results. In clinical practice, usually a combination of the different available diagnostic tests is used. Other tests like impedance testing in the pressure chamber require expensive equipment but do not yield any unique
Correspondence: Dr. med. S. Schr€ oder, Department of Otorhinolaryngology, Head and Neck surgery, Klinikum Bielefeld, Teutoburger Str. 50, 33604 Bielefeld, Germany. Tel.: +49 521 581 3301; Fax: +49 521 581 3399; e-mail: [email protected] © 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
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ORIGINAL ARTICLE
Evaluation of tubomanometry as a routine diagnostic tool for chronic obstructive Eustachian tube dysfunction
692 S. Schr€oder et al.
information. Additionally, most of these tests require an intact tympanic membrane. MRI of the ET and video endoscopy and sonotubometry have not proven to be suitable for daily clinical practice so far.6–8 Tubomanometry (TMM) was first described by Esteve in 2001.9,10 It allows assessment of ET function under defined conditions: swallowing a sip of water triggers the release of a defined pressure (e.g. 30, 40 and 50 mbar) through a nasal applicator. A pressure probe in the external auditory canal registers pressure changes transmitted through movements of the tympanic membrane or through a perforation in the tympanic membrane. Thus, TMM is a semi-objective method to record ET function. As there is no gold standard for the objective assessment of Eustachian tube function and tympanometry alone did not seem sufficient for the evaluation of Eustachian tube function, we started using the TMM in daily routine. So far, there is only little literature on the validity and reliability of this diagnostic device. The purpose of this study was to analyse our own data regarding reliability and validity of TMM. Methods Tubomanometry
Tubomanometry (TMM) was initially produced by La Diffusion Technique Francaise in Saint-Etienne, France, and is now available via Spiggle & Theis in Overath, Germany. The principle of TMM is to deliver defined pressures of 30, 40 and 50 mbar to the epipharynx through a nasal applicator. Swallowing triggers the opening of the cartilaginous part of the ET and at the same time temporarily seals the epipharynx towards the pharynx. A pressure receptor probe sealing the external ear canal registers pressure changes transmitted through movements of the tympanic membrane or even through a perforation in the tympanic membrane. If the ET opens during swallowing, the defined pressure applied to the epipharynx is transmitted to the middle ear. Pressure curves of the epipharynx and the ear canal are displayed on the monitor of the TMM device, and various measuring values are calculated (Fig. 1). Diagrams are created to measure the pressure changes in nasopharynx and ear canal in mbar against the time in seconds (Fig. 2). The opening latency index (R-value) reflects the latency between pressure application in the epipharynx and measurement of a pressure change in the ear canal (R = P1–C1/C2–C1). P1 represents the start of the movement of the eardrum or the pressure increase in the ear canal, respectively, after pressure application. C1 represents the start of the pressure increase in the nasopharynx, and C2 pinpoints the maximum pressure increase in the nasopharynx. Thus, the opening latency index
Fig. 1. Performance of the tubomanometry by Esteve.
quantifies ET function: an immediate opening (R < 1) indicates normal ET function and a late opening (R ≥ 1) indicates restricted ET function. No opening (R negative or not measurable) indicates complete obstruction of the ET.9,10 In patients with patulous ET, the opening is always immediate. In some cases of patulous ET, fluctuations of the pressure in the outer ear canal can be observed after pressure application in the nose (Fig. 2c). TMM is a semi-objective method to record and to some extent quantify ET function. It is not uncomfortable for the patient as well as being quick and easy to perform. Patients
Tubomanometry (TMM) has been used routinely in our department since 2009 on all patients with suspicion of ET dysfunction. We recommend a pressure set-up of 30, 40 and 50 mbar for routine testing. An immediate opening of the ET (R ≤ 1) is rated as normal function, delayed opening (R > 1) hints towards an impaired function, and no opening (negative or not measurable R) means complete obstruction of the ET. Between August and October 2011, 215 healthy subjects (430 ears) underwent TMM once, 25 healthy subjects (50 ears) were examined in weekly intervals for 6 weeks and six healthy subjects (12 ears) were examined three times a day on at least three different days. All subjects underwent physical examination, history, tympanometry, audiometry and tubomanometry. The healthy subjects were volunteers without history of ear diseases or ear surgery and normal eardrums on microscopic examination. In healthy subjects, there were no patients with acute and chronic sinusitis. We compared our results in healthy subjects to our data obtained from 171 patients (342 ears) with chronic obstructive ET dysfunction collected between 2009 and 2012. These patients had a curve type B/C tympanogram and/or recurrent otitis media with effusion in the past 2 years and/or © 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
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(a)
(b)
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(c)
Fig. 2. Tubomanometry (TMM) by Esteve: Pressure curves of the epipharynx and the ear canal. (a) immediate opening (R < 1) indicating normal ET function (b) no opening (not measurable) indicating obstruction of the ET (c) patulous ET with fluctuation of the pressure curve in the ear canal.
subjectively and objectively negative Valsalva. To evaluate reproducibility and reliability, we used data from 11 healthy subjects (22 ears) and 59 patients (118 ears) with chronic obstructive ET dysfunction undergoing repeated measurements with at least 1 week of time in between measurements. In the group of patients with chronic obstructive ET dysfunction, nine patients had previous surgery of the paranasal sinuses but no active signs of disease. The mean age in the 215 healthy subjects was 46 years, and 66.5% were female and 33.5% were male. The mean age in the 171 patients with chronic obstructive Eustachian tube dysfunction was 50 years, and 45% were female and 55% were male. All subjects gave informed consent to the use of all collected data for clinical research and agreed with the participation. Additionally, the findings of 100 tubomanometries were analysed by three experienced otologists independently to evaluate the objectivity of this method, and for the reproducibility, we performed for every pressure three repeated measurements within seconds in 14 ears. All results of the TMM were encoded for the evaluation. An R ≤ 1 was encoded with two points, an R > 1 with 1 point and no R-value with 0 points. Statistical analysis
The inter-rater reliability was tested using intraclass correlation (ICC) which was obtained using mixed models (Stata function xtmixed) for each pressure, separately assuming the independence of the two ears on the same patient. Results
Among the healthy subjects, a constant positive Valsalva was reported for 382 ears (88.8%) and only sometimes positive Valsalva for 28 ears (7.6%) and a negative Valsalva for 10 ears © 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
(3.6%). In 240 ears (55.8%), the Toynbee was always positive; in 58 ears (13.5%) sometimes Toynbee was positive and in 132 ears (30.7%) the Toynbee was negative. Overall, 427 ears were tested in audiometry. Age-related normal findings were obtained in 302 ears (70.7%). The microscopy of the eardrum showed normal findings in all healthy subjects included in the trial, and the objective Valsalva was positive in 82.9% and negative in 17.1% of the ears. 425 of 428 examined ears showed a type A and three ears a type B tympanogram. In the group of patients with chronic obstructive ET dysfunction, the objective Valsalva was positive in 37.4% and negative in 62.6% of the ears. Only 9.1% showed a type A tympanogram, 64.9% a type B and 26% of the ears a type C. The findings of the tympanic membrane in all patients with chronic obstructive ET dysfunction are shown in Table 1. The Tables 2 and 3 demonstrate the results of tubomanometry (TMM) in healthy subjects and patients with chronic ET dysfunction. In healthy subjects, an opening of the ET could be determined in at least 94% at 30–50 mbar and the average R-value always hinted towards an immediate opening (R ≤ 1) in 30. However, the patients with chronic ET dysfunction had an opening of the ET in only 42% at 30 mbar and in 58% at 50 mbar. The average R-value revealed that it was always a delayed opening (R > 1). Not more than 45% of the ears in the ET dysfunction group had an immediate opening of the ET at 30–50 mbar. The range of the R-value in the group of healthy subjects with repeated testing over several weeks was ≤0.99 in 68% and ≤1.99 in 92%. This means the deviations were quite low. Among the patients with chronic obstructive ET dysfunction, 63% (47 of 75) had no R-value at 30 mbar in all measurements and 10% (8 of 75) had an R-value >1 in all measurements with ranges up to 3.45. All other patients had a mixture of opening and no opening of the ET.
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Table 1. Findings of the tympanic membrane in patients with chronic obstructive ET dysfunction
Total number of ears Per cent Valsalva negative Tympanometry Jerger type R-value 50 mbar
Normal findings
Effusion middle ear
Recurrent Effusion
Adhesive process
Cholesteatoma
Retraction
Perforation
192 56.1% 53.5% A: 9.2% B: 51.3% C: 41% ≤1: 26.8% >1: 32.8% No: 40.4%
40 11.7% 76.7% A: 9.3% B: 88.4% C: 2.3% ≤1: 23.3% >1: 32.6% No: 44.2%
27 7.9% 84% A: 12% B: 76% C: 12% ≤1: 20% >1: 28% No: 52%
26 7.6% 82.1% A: 7.1% B: 89.3% C: 3.6% ≤1: 22.1% >1: 29.6% No: 48.1%
9 2.6% 90% A: 20% B: 80% C: 0% ≤1: 50% >1: 20% No: 30%
42 12.3% 53.7% A: 12.5% B: 85% C: 2.5% ≤1: 24.4% >1: 34.1% No: 41.5%
6 1.8% 100% A: 0% B: 100% C: 0% ≤1: 50% >1: 16.7% No: 33.3%
Table 2. Results of the tubomanometry in healthy subjects and patients with chronic obstructive Eustachian tube (ET) dysfunction Chronic obstructive Eustachian tube dysfunction
Healthy subjects
Amount
Opening of the ET No opening of the ET Mean R-value Standard Deviation Minimum R-value Maximum R-value R-value 0.01–1
30 mbar
40 mbar
50 mbar
30 mbar
40 mbar
50 mbar
404 (94%) 26 (6%) 0.83 0.87 0.01 7.62 77.5%
416 (97%) 14 (3%) 0.78 0.74 0.01 7.65 75.2%
418 (97%) 12 (3%) 0.78 1.20 0.01 18.16 82.1%
142 (42%) 200 (58%) 2.43 3.35 0.01 19.00 43%
155 (45%) 187 (55%) 2.41 4.01 0.01 30.42 45.2%
197 (58%) 145 (42%) 2.06 3.21 0.04 30.42 45.7%
Table 3. Results of the tubomanometry using the R-value categories in % Healthy subjects
Chronic obstructive ET dysfunction
R-value
30 mbar
40 mbar
50 mbar
30 mbar
40 mbar
50 mbar
≤1 >1 No R
73 21 6
73 24 3
79.8 17.2 3
18 24 58
20 25 55
26.3 31.7 42
When measurements are repeated in the same healthy subject with a weekly interval for up to six times, the intraclass correlation (ICC) was 0.49 for the TMM with 30 mbar, 0.51 for the TMM with 40 mbar and 0.52 for the TMM with 50 mbar. For the patients with symptoms of ET dysfunction, the ICC for up to four repeated measures with at least a weekly interval was 0.50 for the TMM with 30 mbar, 0.53 for the TMM with 40 mbar and 0.54 for the TMM with 50 mbar. In the three (up to six) times daily measurements, there were no significant fluctuations. The range of the R-value over the day was ≤0.6 with two outliers, and the range of the ET score over the day was ≤1 with one outlier. For TMM with 50 mbar, 38 of 44 measures were in complete agreement, 32 of 44 for the TMM with 40 mbar and 31/44 for the TMM with 30 mbar.
We performed three repeated measurements of the TMM within seconds in 14 healthy persons for 30, 40 and 50 mbar. A complete agreement of the results in the repeated measurements was present in 86% for 30 and 40 mbar and in 79% for 50 mbar. The maximum deviation of the absolute R-value was 2.75 for 30 mbar, 0.96 for 40 mbar and 2.4 for 50 mbar. The ICC was 0.61 for the TMM with 50 mbar, 0.62 for the TMM with 40 mbar and 0.68 for the TMM with 30 mbar. Additionally, 100 randomly selected TMM findings were analysed by three experienced otologists independently to investigate reliability of the results. Inter-rater reliability measures in terms of ICC ranged from 0.83 to 0.90 between the three different pressures (30–50 mbar) with overall 85% of complete agreement between the three raters. Complete results are given in Table 4. There were two cases of non© 2015 John Wiley & Sons Ltd Clinical Otolaryngology 40, 691–697
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adjacent disagreement, and there were no cases of complete disagreement. Discussion
Chronic obstructive dysfunction of the Eustachian tube moved into increased focus of otologists in the past decades. It is acknowledged that Eustachian tube function has a major impact on the healing process after middle ear surgery and plays an important role in the development of otitis media with effusion and cholesteatoma. There is no gold standard for the diagnostic of disorders of the ET. When we started balloon Eustachian tuboplasty (BET) in 2009, we were confronted with the lack of sufficient diagnostic tools for the assessment of chronic ET dysfunction. Most important for the indication of BET are patient history and complaints. In 2012, McCoul et al.11 developed the ETDQ-7, a new instrument to facilitate the collection of clinical data concerning ET function. Our own investigations indicate that the ETDQ-7 is a well reproducible and valid instrument to clinically assess ET function.12 But it is only focused on the subjective complaints of the patients and it does not include any objective data. More objective data can be obtained by the examination of eardrum and nasopharynx. Chronic otitis media with effusion and an adhesive or atelectatic tympanic membrane point to the diagnosis of chronic obstructive ET dysfunction. For this reason, we stared to include Esteve’s tubomanometry into our regular workup of patients with symptoms of ET dysfunction. TMM is easy to perform and a complete examination of both ears takes only about 5 min in the hands of an experienced technician. Another distinct advantage of TMM is that it works in intact as well as perforated eardrums. In our first investigations of tubomanometry in 2009, we found a significant correlation between the results of different investigators and different times of investigation.13 Esteve compared the results of TMM in 58 healthy subjects and 56 patients with chronic otitis media. He described no significant intra-individual variations of the R-parameter. In 67% of healthy subjects, R was ≤1, in 26%, R was >1, and in 7% of healthy subjects, no opening of the ET was observed. In the cohort with chronic otitis media, 13% had an R ≤ 1, 38% had an R > 1, and 51% had no opening of the ET at all.9,10 Table 4. Inter-rater reliability over 34 ears tested by three raters TMM measurement
ICC (95% CI)
Percentage complete agreement
30 mbar 40 mbar 50 mbar
0.90 (0.84, 0.95) 0.83 (0.73, 0.91) 0.87 (0.79, 0.93)
85% (29/34) 70% (24/34) 85% (29/34)
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This data correspond with our results. Esteve believes that the TMM measures not only the function of the ET but also the whole transfer of gas by the ET and the mucosa of the mastoid. Esteve also extracts other helpful information about the middle ear from TMM. For example, can a P2-P1 larger than 0.9 mbar indicate a retraction pocket or an atrophy of the tympanic membrane.10 There are some alternatives to obtain at least semiobjective data on ET function. The clinical examination with Valsalva and Toynbee manoeuvre are daily routine. Both are good indicators for the consistency of the ET but not necessary for the normal function. The opening of the ET can be visible by movements of the tympanic membrane, but might be too weak or rare for normal function. The standard test for the evaluation of the pressure conditions behind the tympanic membrane and indirectly for the function of the ET is tympanometry. It is easy and fast to perform and available to each otologist. More detailed information about ET function is offered by the nine step inflation–deflation test.14 However, this test requires an intact tympanic membrane and is complex and time-consuming. Sonotubometry with perfect sequences (PSEQ) like TMM is employable not only in patients with intact but also perforated eardrums. For sonotubometry, a microphone is placed in the external auditory canal and a loudspeaker in the ipsilateral nostril. The transmission of a continuous tone via the ET into the external auditory canal is recorded. Alterations in the recorded frequencies can be correlated to ET function. Sonotubometry is supposed to be able to detect Eustachian tube openings in both normal and pathological ears.15 Another promising concept is the tensometry with stretch marks on the ear drum. A so far only experimental study could in the future lead to an approach offering long-term measurements of the movements of the ear drum.16 For investigation of the ET with medical imaging, CT and MRI of the temporal bone are important. In recent years, for example, functional MR imaging of the ET was introduced. It is supposed to visualise ET opening during Valsalva manoeuvre.17 Another new approach is the Valsalva CT or special CT sequences during swallowing.18 All of these examinations share of course the disadvantage that they are complex, costly and partly expose the patient to irradiation. The amount of diagnostic approaches to ET function demonstrates that there is a huge interest and a need for reliable diagnostic tools. Most of the recently developed techniques are not used in daily routines. The reason is the missing proof of their functionality, reliability and validity. On the other hand, some are too expensive or not practical in daily routine. Tubomanometry is easy to perform and quickly evaluated. In particular, in combination with other
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clinical tests, it offers promising results. However, the analysis of the results requires some experience. Setting the points to calculate the R-value is critical. A standardised setting to perform the measurement is also essential. The pressure receptor needs to be adjusted, so that it is airtight in the ear canal. Otherwise, measurements might be false negative. We recommend bilateral measurements even if the patient has only unilateral complaints because the intraaural comparison might facilitate the analysis. For example, the ear without complaints might show an immediate opening (R ≤ 1) at 30–50 mbar. The other ear with might only show a delayed opening (R < 1) at 30–50 mbar. This could support the subjective feeling of the patient that the ET of one side works less. We recommend to always measure 30, 40 and 50 mbar in each patient. This can indicate towards the severity of the dysfunction. In patients only suffering from complaints during diving or flights, the measurement at 50 or 40 mbar might be normal (R ≤ 1) but a lower pressure set-up might reveal a delayed opening or no opening, for example, at 30 mbar. Concerning our results in the repeated measurements and the corresponding ICCs, it is hard to say what the reasons for the deviations in the measurements are. On the one hand, the function of the ET might be subject to daily or weekly fluctuations. Thus, TMM can only give a snapshot view on ET function. On the other hand, there might be uncertainties in TMM itself. It seems desirable to improve the accuracy of the receptors and to try to implement measurements without additional pressure. This means objectifying the Valsalva manoeuvre. The cut-off points of the R-value were suggested by Esteve and co-workers. The accuracy of these values should be further investigated. For the assessment of ET function, it might be sufficient to distinguish between a visible R-value and no visible opening of the ET. However, TMM can be considered a useful additional diagnostic tool in patients with chronic obstructive ET dysfunction. It should not be used as the only instrument for diagnosing diseases of the ET but as an additional semi-objective tool. We use the TMM as the more objective part of the ETS-7 (Eustachian tube score) for the evaluation of ET function.19 In particular, due to its suitability for daily routine, tubomanometry is worth refining. Conclusion
Tubomanometry (TMM) can support the diagnosis of a dysfunction of the ET. An R-value ≤1 indicates a normal ET function, an R-value >1 indicates a delayed opening of the ET, and no definable R-value means no opening of the ET. TMM is a reliable and valid instrument to support the diagnosis of chronic obstructive ET dysfunction.
Keypoints
• •
The Tubomanometry is an additional diagnostic tool to evaluate the Eustachian tube function. The R-value seems to be a good indicator.
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17 L€ ukens A., Dimartino E., G€ unther R.W. et al. (2012) Functional MR imaging of the eustachian tube in patients with clinically proven dysfunction: correlation with lesions detected on MR images. Eur. Radiol. 22, 533–538 18 McDonald M.H., Hoffman M.R., Gentry L.R. et al. (2012) New insights into mechanism of Eustachian tube ventilation based on
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cine computed tomography images. Eur. Arch. Otorhinolaryngol. 269, 1901–1907 19 Schr€ oder S., Lehmann M., Sauzet O. et al. (2015) A novel diagnostic tool for chronic obstructive Eustachian tube dysfunction -The Eustachian Tube Score. Laryngoscope 125, 703–708
