Negative Middle Ear Pressure Research Articles

Pathogenesis of Retraction Pocket of the Tympanic Membrane-A Narrative Review.

Several theories describe the development of the retraction pocket of the tympanic membrane (RP). Many authors suggest that the negative middle ear pressure is the main reason responsible for developing this condition. A narrative review has been undertaken, and conclusions are drawn reflecting a current knowledge with our new observations in the histological and immunohistochemical study. Recent studies show the important role of inflammation in the development and progression of RP. A review of the available literature shows that the inflammation plays a key role in pathogenesis of the RP and its progression to the cholesteatoma. We support this statement with our new results from histological and immunohistochemical analysis of the RPs.

Methods to Improve the Efficacy of Autoinflation Procedures and to Classify Eustachian Tube Patency

We describe three methods to improve the efficacy of autoinflation procedures. The subjects were examined after flight with otoscopy and tympanometry. If the middle ear pressures after flight were negative, the passengers were asked to perform a Valsalva maneuver after which tympanometry was repeated. If still negative, the passengers were instructed to perform an extended Valsalva maneuver. If middle ear pressure was still negative, the passenger then was instructed to perform autoinflation using a nasal balloon. Among the ears with initial negative middle ear pressure, 14% normalized the middle ear pressure after Valsalva’s maneuver. In the passengers with a remaining negative pressure, the pressure was equalized to zero or positive pressure in 46% following an extended Valsalva maneuvre. In the ears with remaining negative middle ear pressure after both Valsalva and extended Valsalva maneuver, 69% could normalize the middle ear pressure after nasal balloon inflation.

Differences between Pressurized and Non-Pressurized Transient-Evoked Otoacoustic Emissions in Neonatal Subjects

Introduction: Recently, Interacoustics presented a new otoacoustic emission protocol where the probe pressurizes the ear cavity, thus eliminates the risk of non-assessment (REFER outcome) due to a negative middle ear pressure. This study evaluated the characteristics and the performance of this new protocol on a newborn well-baby population. Methods: One hundred sixty-three newborns (age 2.7 ± 1.1 days) for a total of 294 ears were assessed randomly. Transiently evoked otoacoustic responses were acquired by the Titan device (Interacoustics), using the default and a pressurized TEOAE protocol. The data were analyzed in terms of signal to noise ratios (S/Ns) at 5 frequencies, namely, 0.87, 1.94, 2.96, 3.97, and 4.97 kHz. To assess any possible gestational age (GE) effects on the TEOAE variables, the responses were subdivided in 4 different age subgroups. Results: There were no significant differences between the left and right ear TEOAE responses, for age (in days), GE (in weeks), weight (in grams), and S/N at all 5 frequencies. Considering the pooled 294 ears, paired t tests between the default and the pressurized TEOAE data showed significant differences across all 5 frequencies (p < 0.01). The pressurized protocol generated TEOAE responses presenting larger S/Ns, and a positive additive effect of approximately 2.31 dB was observed at all tested frequencies. There were no significant GE effects on the pressurized TEOAE responses. In terms of performance, both protocols performed equally (same number of PASSes). Conclusion: The pressurized TEOAE protocol generates responses with higher S/Ns which might be useful in borderline cases where the middle ear status might cause a REFER screening outcome.

Should middle ear pressure and hearing loss be evaluated prior to septoplasty? A prospective cohort study

Background/Aim: Nasal resistance is primarily caused by the deviation of the nasal septum at the level of the inferior turbinate and isthmus nasi. The pressure of the nasopharynx may decrease to less than that of the middle ear, from where the air would drain, thus creating a cavity with negative pressure. Therefore, pathological phenomena in the nasal cavity can affect the ventilation of the middle ear. In this study, we aimed to investigate how hearing is changed by septum deviation (SD) affecting middle ear pressure, and in case of hearing loss, whether there is any improvement after nasal surgery. Methods: Sixty-seven patients were admitted to our Otorhinolaryngology clinic with nasal obstruction and hearing loss complaints, and 50 patients (≥18 years of age) with nasal congestion due to SD were included in this study. Septoplasty was performed to fifty patients and lateralization of SD was noted. Pure tone audiometric and tympanometric evaluations were performed preoperatively and postoperatively. Gain of hearing and gain of pressure after surgery were recorded, which were statistically compared between the groups. Results: Of the 50 patients with nasal congestion and hearing impairment included in our study, 27 were male and 23 were female. The mean age of all cases was 32.08 (9.44) years, ranging between 18–56 years. Among forty-two patients with unilateral SD, thirty-seven (88%) had negative middle ear pressure. The lowest pure-tone-threshold was 1 dB, and the highest was 35 dB on the side with the deviation. On the side without SD, the lowest threshold was 8 dB, and the highest was 28 dB. Pure-tone-thresholds between 500 and 2,000 Hz were within normal range in seventy-six ears. Hearing loss was present in twenty-four ears. Postoperatively, the lowest hearing gain was 0 dB, and the highest was 15 dB on the side with the SD. On the side without SD, the lowest and highest hearing gains were 0 dB and 11 dB. Conclusion: The negative pressure in the middle-ear due to SD may affect hearing. Hearing loss does not result from every deviation but occurs only when sufficient negative pressure is formed in the middle-ear.

Tragal perichondrium as graft material in tympanoplasty: our experience

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; It has been defined as a permanent abnormality of pars tensa or flaccida, as a result of acute otitis media, negative middle ear pressure or otitis media with effusion. It manifests clinically as ear discharge and decreased hearing and may lead to numerous changes in the tympanic membrane, middle ear cleft, and mastoid air cell system. It has been classified into two types: mucosal and squamosal types. Chronic otitis media (COM) is a very common condition in developing countries in both adult and paediatric age groups. This study has been conducted to determine the outcome and graft uptake of tragal perichondrium in type 1 tympanoplasty.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; The prospective analytical study was conducted department of otorhinolaryngology, School of Medical Sciences and Research, Greater Noida, Uttar Pradesh, India over a period of 12months from 01 January 2019 to 31 December 2019. 30 patients according to inclusion criterion underwent tympanolpasty using tragal perichondrium were included in study. The data obtained was analyzed using statistical package for the social sciences (SPSS), version 21.0. P value less than 0.05 was taken as statically significant. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Preoperative mean hearing loss was 38.45±7.01 dB, mean air bone gap was 20.20±3.75 dB, and postoperative air bone gap was reduced to an average of 10.86±3.82 dB. 8.51 dB of hearing gain was achieved and an air bone gap réduction of 8.51 dB was observed.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Our study concluded tragal perichondrium is a suitable graft material is n mucosal type of COM.&lt;/p&gt;

Can the negative pressures found in obstructive sleep apnea and Eustachian tube dysfunction be related?

ObjectiveThe association between obstructive sleep apnea (OSA) and Eustachian tube dysfunction (ETD) is well known. When both exist in a single pediatric patient, one of the expected culprits is adenoid enlargement. We hypothesize, in contrast, that the negative pharyngeal pressure found in OSA may be transmitted to the middle ear as negative middle ear pressure (MEP), which subsequently results in pathology. The objective of this study was to determine whether the degree of OSA and MEP are associated while using MEP as a quantifiable measurement of ETD. Study designRetrospective chart review. SettingTertiary academic center (Jan 2000–Jan 2018). Subjects and methodsThe relationship between apnea-hypopnea index (AHI) and MEP was examined. A non-anatomic model was utilized to support causality. ResultsThirty-four pediatric patients and twenty-three adult patients were included in the analysis. REM AHI showed a moderate negative correlation with MEP in children (r = -0.265), and a weak positive correlation with MEP in adults (r = 0.171). Children with an AHI in the severe OSA category had a more negative mean MEP than those in the mild category (p = 0.36). Adults with an AHI in the severe OSA category had a more positive mean MEP than those in the mild category (p = 0.11). ConclusionIn children, increasing severity of OSA is associated with a negative MEP, suggesting that negative pressure associated with OSA may be transmitted to the middle ear. In adults, increasing severity of OSA is associated with a more positive MEP.

Laser vs microdebrider eustachian tuboplasty for the treatment of chronic adult eustachian tube dysfunction: A systematic review.

ObjectivesMultiple treatments are described in the literature for the treatment of chronic Eustachian tube dysfunction but high-level quality evidence seems missing to support these treatments. This systematic review aimed to determine and compare the safety and efficacy of Laser Eustachian tuboplasty and Microdebrider Eustachian tuboplasty as a treatment for long-term Eustachian tube dysfunction.Data sourcesA total of 12 electronic databases were searched up to April 2018 for published and unpublished literature in the English language. References of included studies were checked.MethodsA systematic review was undertaken. Outcomes assessed were: primary outcomes-subjective improvement in symptoms (ETDQ-7), audiometric improvement of hearing, improvement of negative middle ear pressure noticed in tympanometry, objective improvement of tympanic membrane retraction. Secondary outcomes were-the ability to auto-insufflate Eustachian tube i.e. Valsalva manoeuvre, improved quality of life, passive tubal opening, tubomanometry, swallowing test, reduction in mucosal inflammation of Eustachian tube orifice in the nose, complications from the procedure, the need for further procedures. Results are reported in a narrative synthesis as a meta-analysis was not possible due to heterogeneous data.ResultsThree studies were included. All included studies were small-scale case series (13–38 participants). Studies were conducted outside the UK. Subjective and objective improvement of Eustachian tube function was reported in all studies. But all included studies were at high risk of bias and subject to multiple limitations. No major complications were reported in either study.ConclusionsBased on current evidence, it is not possible to recommend the clinical use of either of these two interventions i.e. Laser or Microdebrider Eustachian tuboplasty. Lack of controlled studies was identified as a gap in the evidence. Future research should be directed toward designing randomised controlled trials. These trials should use strict standard methodology and reporting criteria. Future trials should make use of consensus statement document about Eustachian tube dysfunction definition, diagnostic methods, and outcome assessment criteria to design clinical trials.

Effects of Probe Tip Placement on Static Acoustic Admittance at the Plane of Measurement

Abstract Introduction: Tympanograms are recorded at the plane of the probe tip in the ear canal, consequently, this recording is called a tympanogarm in the plane of measurement and it includes both the acoustic admittance of the trapped volume of air between the probe tip and the tympanic membrane and the admittance of the middle ear system at the tympanic membrane. Materials and Methods: Eighty three participations (166 ears- 85 right ears, 81 left ears) were selected for the study. participants who had negative middle ear pressure greater than -50dapa and + 50 dapa and air and bone conduction thresholds gap of equal or more than 15 dB were excluded from the study. Data Analysis: Pearson correlation coefficient was carried out to see the relationship between residual ear canal volume (RECV) and acoustic admittance (Ya) and as well as for the tympanometric peak pressure (TPP). Results: Results shows there is strong positive correlation (r =0.854, P &lt;0.001) between the residual volume in the ear canal and admittance. Acoustic admittance were well correlated with the residual ear canal volume with coefficient of determination of r^2 = 0.793. In case of the middle ear pressure, it has been shown that there is positive moderate correlation (r = 0.679, P &lt; 0.001) between the middle ear pressure and acoustic admittance with coefficient of determination of r^2 = 0.473. Conclusion: The shift of probe tip placement in the ear canal and middle ear pressure variation changes the acoustic admittance value during immitance audiometry.

OCENA ABSORBANCJI SZEROKOPASMOWEJ U DOROSŁYCH Z PODCIŚNIENIEM I NADCIŚNIENIEM W UCHU ŚRODKOWYM

BackgroundMiddle ear pressure plays a vital role in the transmission of sound to the inner ear. However, limited research data exists to understand the effect of abnormal middle ear pressure on wideband absorbance (WBA) tympanometry. The purpose of the study was to evaluate WBA at peak pressure and ambient pressure in adults with abnormal positive and negative middle ear pressure and compare them with normal adult ears having normal middle ear pressure.Material and methodsThree groups of adults – normal middle ear pressure group (56 ears), negative middle ear pressure group (30 ears), and positive middle ear pressure group (15 ears) – in the age range 22 to 50 years were considered. WBA was measured at peak and ambient pressures across the frequencies from 250 to 8000 Hz.ResultsWBA at peak pressure was observed to be higher than at ambient pressure in all the groups, with the difference seen mostly at low and mid-frequencies up to 2000 Hz. The negative middle ear pressure group showed the most considerable difference in mean WBA, seen between 600 Hz and 1000 Hz, followed by the positive middle ear pressure group, with a negligible difference for the normal middle ear pressure group.ConclusionsThe study highlighted the importance of measuring WBA at peak pressure and ambient pressure. The results suggest that the comparison of WBA at peak and ambient pressures, especially from lower to mid-frequencies up to 2000 Hz, would help in differentiating abnormal negative/positive pressure from normal middle ear pressure and also between ears having negative and positive pressure.

Vibration Measurements of the Gerbil Eardrum Under Quasi-static Pressure Steps.

Tympanometry is a relatively simple non-invasive test of the status of the middle ear. An important step towards understanding the mechanics of the middle ear during tympanometry is to make vibration measurements on the eardrum under tympanometric pressures. In this study, we measured in vivo vibration responses in 11 gerbils while varying the middle-ear pressure quasi-statically, with the ear canal at ambient pressure. Vibrations were recorded using a single-point laser Doppler vibrometer with five glass-coated reflective beads (diameter ~ 40μm) as targets. The locations were the umbo, mid-manubrium, posterior pars tensa, anterior pars tensa and pars flaccida. As described in earlier studies, the unpressurized vibration magnitude was flat at low frequencies, increased until a resonance frequency at around 1.8-2.5kHz, and became complex at higher frequencies. At both the umbo and mid-manubrium points, when the static pressure was decreased to the most negative middle-ear pressure (- 2500Pa), the low-frequency vibration magnitude (measured at 1.0kHz) showed a monotonic decrease, except for an unexpected dip at around - 500 to - 1000Pa. This dip was not present for the pars-tensa and pars-flaccida points. The resonance frequency shifted to higher frequencies, to around 7-8kHz at - 2500Pa. For positive middle-ear pressures, the low-frequency vibration magnitude decreased monotonically, with no dip, and the resonance frequency shifted to around 5-6kHz at + 2500Pa. There was more inter-specimen variability on the positive-pressure side than on the negative-pressure side. The low-frequency vibration magnitudes on the negative-pressure side were higher for the pars-tensa points than for the umbo and mid-manubrium points, while the magnitudes were similar at all four locations on the positive-pressure side. Most gerbils showed repeatability within less than 10dB for consecutive cycles. The results of this study provide insight into the mechanics of the gerbil middle ear under tympanometric pressures.

“EFFECT OF ANTERIOR NASAL PACKING ON MIDDLE EAR FUNCTION AND HEARING: A PROSPECTIVE STUDY”

Introduction- The Eustachian tube provides an anatomic communication between the middle ear and nasopharynx, and maintains pressure equality across the tympanic membrane. Objective- To see the effect of anterior nasal packing on Otological symptoms, middle ear pressure and hearing Materials and method- This prospective study was carried out during period of September 2018 till August 2019. 100 ears were taken in the study. Middle ear pressure and hearing threshold were evaluated by Tympanometry and Audiometry respectively. Results- Postoperatively two days after anterior nasal packing, there was increase in no. of patient ears with ear fullness, ear ache, tinnitus, hearing threshold and abnormal negative middle ear pressure. After removal of nasal packing up to twelve weeks, improvement in middle ear pressure and hearing threshold was seen. Conclusion- Anterior nasal packing causes decrease in middle ear pressure and increase in hearing threshold. Key words- Eustachian tube, Middle ear pressure, Hearing threshold

Tympanoplasty using wet temporalis fascia graft at tertiary care hospital

Diagnosis of chronic otitis media implies a permanent abnormality of the pars tensa or flaccida, most likely result of earlier acute otitis media, negative middle ear pressure or otitis media with effusion. It results in some degree of conductive hearing loss due to perforated tympanic membrane with or without ossicular distruction. This condition is treated by tympanoplasty in which we do the repair of tympanic membrane with the help of temporalis fascia graft. In our study we used the wet temporalis fascia graft. We did an observational study of 40 cases of COM inactive Mucosal type and found that 39 cases had the better graft placement and shorter uptake time as well as the operative time. And also there was significant improvement in the hearing post operatively which was assessed by pure tone audiometry. However, a larger sample size would help further establish the validity or relevance of our study. Keywords: COM, Tympanoplasty, Wet Temporalis Fascia Graft.

Change in Eustachian Tube Function With Balloon Dilation in Adults With Ventilation Tubes.

Assess the changes in Eustachian tube (ET) function (ETF) with balloon dilation of Eustachian tube (BDET). Prospective cohort for repeated testing measures. Clinical research center. Eleven adults with at least one patent ventilation tube (VT) inserted for chronic ET dysfunction (ETD) and history of otitis media with effusion. Subjects with evidence of moderate to severe ETD on the side with a VT underwent unilateral BDET. Changes in ETF parameters after BDET measured by Forced Response Test (FRT), Inflation Deflation Test (IDT), and Pressure Chamber test. With the FRT at 11 ml/min, opening pressure (OP) decreased from 458 ± 160 to 308 ± 173 daPa and closing pressure (CP) from 115 ± 83 to 72 ± 81 daPa at the 3-month post-BDET visit. The IDT and Pressure Chamber test showed that the percentage of middle ear (ME) pressure gradient equilibrated with swallows improved from 28 ± 34 to 53 ± 5% for positive and from 20 ± 28 to 38 ± 43% for negative ME pressure. Images from the pre- and post-BDET functional CT scans did not show apparent changes in the anatomy. Comparisons of ETF test parameters pre- and post-BDET suggested that the ET was easier to open and stayed open longer after the procedure. However, during the limited duration of follow-up most subjects continued to have ETD, some requiring VT re-insertion after the study period. Adults with severe ETD may benefit from BDET, however ETD may not be completely resolved and patients may continue to need VTs.

Which is Better for Management of Tympanic Membrane Perforation Temporalis Fascia or Fascia Lata Graft?

A good graft material is the one which is easily available and harvestable, tough and is easy to be handling and survival is good. Both temporalis fascia and fascia lata graft satisfy all these criteria. Keeping all these factors in mind, the comparative study of temporalis fascia and fascia lata graft in tympanoplasty is undertaken. All the patient reporting to ENT OPD with tympanic membrane perforation who are fit for surgery were advised tympanoplasty or tympanoplasty with mastoidectomy were included in the study. Our observation and data analysis have shown that fascia lata is definitely better than temporalis fascia in terms of intactness of graft (95.1% in fascia lata and 90.24% in temporalis fascia) and PTA average improvement is higher in fascia lata graft (11.56 ± 5.005) as compared to temporalis fascia graft (10.32 ± 4.634) and ABG improvement is higher in fascia lata graft (2.7317 ± 1.118) as compared to temporalis fascia graft (2.634 ± 1.089). Fascia lata has better dimensional stability, easy handling and thickness of the graft and it provides more resistant to negative middle ear pressure. Hence, fascia lata is one of the good choices in otologist's armentorium for tympanoplasty graft material.

Effect of Anterior Nasal Packing on Eustachian Tube Function and Middle Ear Pressure

The present study includes evaluation 60 ears of 30 nasal patients admitted to department of Otolaryngology and Head-Neck Surgery at Banghabandhu Sheikh Mujib Medical University. Each patient underwent nasal surgery followed by anterior nasal packing for 48 hours. All patients were investigated by tympanometry prior to surgery, 2nd post operative day before pack removal and on 7th post operative day 5 days after pack removal. This study shows that nasal packing result in Eustachian tube dysfunction and negative middle ear pressure which is reversible in nature.&#x0D; Bangladesh J Otorhinolaryngol; April 2017; 23(1): 27-31

Comparative study of cartilage tympanoplasty with temporalis fascia tympanoplasty

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; The aim of our study is comparison of effectiveness of cartilage (conchal or tragal) tympanoplasty with temporalis fascia tympanoplasty in terms of graft uptake and audiological outcomes. Help of following databases were taken: MEDLINE, emedicine, Google scholar, and the PubMed.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; We studied the outcome of two different type of graft material (cartilage and temporalis fascia). Who underwent type 1 tympanoplasty at department of otorhinolaryngology, RUHS College of Medical Sciences, Jaipur from November 2015 to November 2018. Total 80 patients were divided in two groups, 40 patients underwent cartilage grafting while 40 patient’s tympanoplasty was done using temporalis fascia graft. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; The successful graft uptake rate for the fascia group was 90%, and that for the cartilage group was 97.5%. Though initial audiological improvements were better in fascia graft group, long term results were similar in both groups.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; The use of cartilage tympanoplasty has similar outcomes to temporalis fascia grafting for audiological purpose. But successful uptake rate is better for cartilage as it is elastic, more resistant to resorption and retraction from more negative middle ear pressure.&lt;/p&gt;

Eustachian Tube Dysfunction and Wideband Absorbance Measurements at Tympanometric Peak Pressure and 0 daPa

Although wideband absorbance (WBA) provides important information about middle ear function, there is limited research on the use of WBA to evaluate eustachian tube dysfunction (ETD). To date, WBA obtained under pressurized condition has not been used to evaluate ETD. The objective of the study was to compare WBA at 0 daPa and tympanometric peak pressure (TPP) conditions in healthy ears and ears with ETD. A cross-sectional study design was used. A total of 102 healthy ears from 79 participants (mean age = 10.0 yr) and 43 ears from 32 patients with ETD (mean age = 16.0 yr) were included in this cross-sectional study. WBA was measured at 0 daPa (WBA₀) and TPP WBA at TPP (WBATPP). WBA results were analyzed using descriptive statistics and t-tests with the Bonferroni correction. An analysis of variance with repeated measures was applied to the data. WBA₀ was significantly lower in the ETD group than in the control group. The WBA₀ of the control group demonstrated a broad peak between 1.25 and 4 kHz, whereas the WBA₀ of the ETD group had a peak between 2.5 and 4 kHz. WBATPP of the ETD group approached values close to that of the control group. In the control group, WBATPP was only 0.06 to 0.09 higher than WBA₀, whereas in the ETD group, WBATPP was 0.29 to 0.42 higher than WBA₀ between 0.6 and 1.5 kHz. A differential pattern of WBA at TPP relative to 0 daPa was observed between ears with ETD and ears with otitis media with effusion (OME) and negative middle ear pressure (NMEP). Hence, a comparison of WBA₀ and WBATPP can provide potentially useful diagnostic information, and hence can be used as an adjunct tool to evaluate ETD. This is important especially in young children or some adults who are unable to perform maneuvers such as Toynbee or Valsalva during ETD assessment. Further research is needed to verify the results using test performance measures to determine whether WBA₀ and WBATPP can objectively determine the presence of ETD or OME with NMEP.

Effect of Negative Middle Ear Pressure and Compensated Pressure on Wideband Absorbance and Otoacoustic Emissions in Children.

Objective This study investigated pressurized transient evoked otoacoustic emission (TEOAE) responses and wideband absorbance (WBA) in healthy ears and ears with negative middle ear pressure (NMEP). Method In this cross-sectional study, TEOAE amplitude, signal-to-noise ratio, and WBA were measured at ambient and tympanometric peak pressure (TPP) in 36 ears from 25 subjects with healthy ears (age range: 3.1-13.0 years) and 88 ears from 76 patients with NMEP (age range: 2.0-13.1 years), divided into 3 groups based on NMEP (Group 1 with TPP between -101 and -200 daPa, Group 2 with TPP between -201 and -300 daPa, and Group 3 with TPP between -301 and -400 daPa). Results Mean TEOAE amplitude, signal-to-noise ratio, and WBA were increased at TPP relative to that measured at ambient pressure between 0.8 and 1.5 kHz. Further decrease in TPP beyond -300 daPa did not result in further increases in the mean TEOAE or WBA at TPP. The correlation between TEOAE and WBA was dependent on the frequency, pressure conditions, and subject group. There was no difference in pass rates between the 2 pressure conditions for the control group, while the 3 NMEP groups demonstrated an improvement in pass rates at TPP. With pressurization, the false alarm rate for TEOAE due to NMEP was reduced by 17.8% for NMEP Group 1, 29.2% for NMEP Group 2, and 15.8% for NMEP Group 3. Conclusion Results demonstrated the feasibility and clinical benefits of measuring TEOAE and WBA under pressurized conditions. Pressurized TEOAE and WBA should be used for assessment of ears with NMEP in hearing screening programs to reduce false alarm rates.

Measuring dynamic Eustachian tube function using tympanometry in a pressure chamber: the effect of nasal betahistine application

To assess the effect of topical betahistine on Eustachian tube function in subjectively abnormal subjects in a hyperbaric chamber. Active and passive Eustachian tube function was examined using tympanometry in a pressure chamber. Active Eustachian tube function was tested against the negative middle ear pressure induced by increasing the chamber pressure to +3 kPa. One voluntary swallow decreased middle-ear pressure by a mean of 1.36 kPa. Passive Eustachian tube function was tested by measuring spontaneous Eustachian tube openings as the chamber pressure dropped from +10 kPa to ambient. Four distinct patterns of Eustachian tube behaviour were seen, three of which indicated Eustachian tube dysfunction. Betahistine had no positive effect on Eustachian tube opening, although previous animal studies had suggested a beneficial effect. Topical betahistine had no effect on Eustachian tube function. Combining a hyperbaric chamber with tympanometry proved ideal for evaluating Eustachian tube function.

The clinical value of wideband tympanometry in the diagnosis of otitis media with effusion

Objective:To establish normative data for wideband absorbance measurements in Chinese with normal ear and effusion ear using wideband tympanometry(WBT) and determine the WBT curves of normal ears and effusion ears to facilitate the use of it. To investigate whether there are difference between the WBT absorbance in children aged 2-16 and adults above 16. To compare the sensitivity and specificity of WBT and conventional tympanometry tests for diagnosing otitis media with effusion (OME).Method:One hundred and seventy-six patients(342ears) ,from January 2015 to December 2015, were enrolled, including 96 males and 80 females whose ages ranged from 2 to 74 years. All of these patients, who underwent physical examination, ear endoscopy, conventional tympanometry and pure tone audiometry, were divided into three groups, namely normal, negative pressure and effusion according to the clinical diagnosis. WBT was carried out in these patients to analyze whether there are difference in the absorbance between children and adults in normal ears.The absorbance diagram of normal, effusion and negative pressure ears were mapped in Chinese population.The normal WBT curve was named as type N (normal) curve, the middle ear effusion curve as type E (effusion) curve, and the middle ear negative pressure curve as type P (negative pressure) curve. Pairwise comparison was carried out to analyze the difference of the WBT absorbance among these WBT curves. Other 40 patients (66 ears) with clinical diagnosis of middle ear effusion, including 22 males and 18 females with ages ranged from 3 to 36 years old, underwent exploratory tympanotomy. These 40 cases were detected preoperatively by both conventional tympanometry and WBT by which the sensitivity and specificity were compared in the diagnosis of middle ear effusion.Result:The normative data of WBT absorbance in Chinese with normal ear over 2 years old was established. The WBT absorbance at all frequencies between children and subject over 16 years old showed no statistically significant difference except for 10 frequencies in all 31 frequencies detected. The variations in the absorbance were mainly concentrated on the frequencies ranged from 500- 2000 Hz,in patients with OME. In the frequency range of 500-2000 Hz, the absorbance amplitudes in type N curv >type P curve>type E curve. There were significant differences in WBT absorbance at all frequencies between type N and type E between within 500-2000 Hz.The sensitivity and specificity of WBT for middle ear effusion were 94.8% and 87.5%, respectively, which were higher than that of conventional tympanometry with 91.3% of the sensitivity and 62.5% of the specificity.Conclusion:The WBT absorbance is consistent at most of the frequencies in Chinese. The normal ear, effusion and negative pressure in the middle ear can be distinguished by WBT curve. WBT can be useful for clinical diagnosis of OME, which has a higher sensitivity and specificity than conventional tympanometry.