Eustachian tube-tensor veli palatini muscle-cranial base relationships in children and adults: an osteological study

The relationship between dimensions of the Eustachian tube and acquired attic cholesteatoma

Objective

This study investigated the relationship between physical dimensions of the Eustachian tube and the emergence of primary attic cholesteatoma.

Methods

A total of 31 patients with unilateral attic cholesteatoma were selected for radiological comparison. Standard point measurements as well as specific measurements were performed using imaging software. The length, narrowest diameter and bony segment volume, and pharyngeal orifice diameter of both sides of the Eustachian tube (attic cholesteatoma and healthy control ears) were measured and compared.

Results

Comparison of the values did not reveal any statistically significant difference between the attic cholesteatoma ears and the healthy control ears in terms of: Eustachian tube height, narrowest diameter, bony segment volume or pharyngeal orifice diameter.

Conclusion

No statistically significant difference was found between the cholesteatoma ears and the healthy control ears in terms of the osseous Eustachian tube size. The findings indicate that the Eustachian tube bony segment dimensions and pharyngeal orifice diameter are not factors in attic cholesteatoma development.

Identification of critical windows in early development of human upper respiratory tract and middle ear disease

Otitis media (OM) or middle ear disease is a prevalent pediatric condition generally related to early growth of the cartilaginous Eustachian tube (CET). This study used a developmental series of dry crania to reconstruct CET and dilator tubae (DT, the muscle opening the CET) morphology. Timing and directionality of CET and upper respiratory tract (URT) growth were investigated. Traditional and 3D geometric morphometrics (GM) were used to assess bony landmarks on the crania. The series was divided using dental eruption into seven growth stages ranging from before eruption of deciduous dentition (approximately the first 6 postnatal months) to eruption of the first permanent maxillary molar (after approximately 6 years). Bony endpoints of the CET and DT were used to calculate their morphology. GM analysis showed substantial shape differences between newborns, early infants, and all later developmental stages. Univariate measures showed the largest growth change between birth and 6 months. Subsequently, CET morphology changed little in the latter half of year 1, instead maturing gradually until approximately 3 years whereas DT relative length and orientation finish growth by the end of year 1. Incongruence in slower CET growth and faster DT growth could impact CET function between 6 and 12 months and be a contributing factor of OM. Tubal aeration may improve after this time when both CET and DT morphology mature, coinciding with clinically reported drop-off in ear infections.

Multi-scale modeling of an upper respiratory airway: Effect of mucosal adhesion on Eustachian tube function in young children

BACKGROUND

The Eustachian tube is a collapsible upper respiratory airway that is periodically opened to maintain a healthy middle ear. Young children, <10 years old, exhibit reduced Eustachian tube opening efficiency and are at risk for developing middle ear infections. Although these infections increase mucosal adhesion, it is not known how adhesion forces alters the biomechanics of Eustachian tube opening in young children. This study uses computational techniques to investigate how increased mucosal adhesion alters Eustachian tube function in young children.

METHODS

Multi-scale finite element models were used to simulate the muscle-assisted opening of the Eustachian tube in healthy adults and young children. Airflow during opening was quantified as a function of adhesion strength, muscle forces and tissue mechanics.

FINDINGS

Although Eustachian tube function was sensitive to increased mucosal adhesion in both adults and children, young children developed Eustachian tube dysfunction at significantly lower values of mucosal adhesion. Specifically, the critical adhesion value was 2 orders of magnitude lower in young children as compared to healthy adults. Although increased adhesion did not alter the sensitivity of Eustachian tube function to tensor and levator veli palatini muscles forces, increased adhesion in young children did reduced the sensitivity of Eustachian tube function to changes in cartilage and mucosal tissue stiffness.

INTERPRETATIONS

These results indicate that increased mucosal adhesion can significantly alter the biomechanical mechanisms of Eustachian tube function in young children and that clinical assessment of adhesion levels may be important in therapy selection.

Comparative Assessment of Cephalometric and Tympanometric Readings in Down Syndrome

Aim  The purpose of this study was to conduct a comparative assessment of the various cephalometric and auditory parameters between patients with Down syndrome (DS) and healthy controls. Methods The cephalometric and auditory parameters were divided among 50 participants into two equal sets, DS (n = 25) and controls (n=25), and assessed. While a standard cephalometric analysis was conducted to measure the hard tissue parameters, tympanometry was used to assess the audiological parameters. Results The values of the linear and angular cephalometric parameters of the DS group were found to be lower than the controls. All the controls recorded type A tympanogram while the DS group recorded type A, B, and C tympanograms. A significant relationship was observed in the cephalometric readings - eustachian tube (ET) length, posterior upper facial height (PUFH) length, sella (s)-basion (ba)-palatal length (PL), and s-ba-ET angles - among the subjects who presented with type B or C tympanogram in comparison to those with type A. Conclusion  Tympanometry, a highly sensitive and relatively simple test to assess audiological parameters, has a significant relationship with a number of cephalometric indicators of growth and development. A deviation from the normal tympanometric readings can be used as an early indicator of the impending craniometric aberrations and handicap. This can be used as an effective tool for early intervention in cases of DS. Patients who have recorded abnormal tympanograms on multiple occasions over a period of six months can be subjected to a further cephalometric analysis.

Can lateral nasopharyngeal radiographs be used to predict eustachian tube dysfunction?

The objective of our case-control study was to determine whether craniofacial features on lateral nasopharyngeal radiographs (LNPRs) can predict eustachian tube dysfunction (ETD). The study included patients seen in the otolaryngology clinic from 2005 to 2011. Patients 0 to 10 years old with pressure equalization tube (PET) placement and LNPR within 6 months were included. Measurements were compared with age-matched controls selected at random to identify craniofacial features associated with ETD. Using receiver operating curve methodology, selected measurements were used to correlate age, craniofacial features, and ETD. The study population consisted of 32 patients and 34 controls. No significant differences were found between groups on any individual measurement: cranial base angle; lengths of anterior, middle, and total skull base; mandible; hard and soft palates; sella-soft-palate tip; sella-posterior nasal spine; and nasopharyngeal and palatal airway. Further statistical analysis demonstrated that patients who required PETs were more likely to have shortened anterior cranial base and maxilla relative to mandibular length. Contrary to the findings of previous studies, no single measurement was found to identify craniofacial features that may select for children with ETD requiring PETs. However, younger patients with a smaller cranial base and/or maxilla relative to mandibular length are more likely to require PETs, implying persistent ETD.

Cranial Indicators Identified for Peak Incidence of Otitis Media

Acute otitis media (AOM) is one of the most common pediatric conditions worldwide. Peak age of occurrence for AOM has been identified within the first postnatal year and it remains frequent until approximately six postnatal years. Morphological differences between adults and infants in the cartilaginous Eustachian tube (CET) and associated structures may be responsible for development of this disease yet few have investigated normal growth trajectories. We tested hypotheses on coincidence of skeletal growth changes and known ages of peak AOM occurrence. Growth was divided into five dental eruption stages ranging from edentulous neonates (Stage 1) to adults with erupted third maxillary molars (Stage 5). A total of 32 three-dimensional landmarks were used and Generalized Procrustes Analysis was performed. Next, we performed principal components analysis and calculated univariate measures. It was found that growth change in Stage 1 was the most rapid and comprised the largest amount of overall growth in upper respiratory tract proportions (where time is represented by the natural logarithmic transformation of centroid size). The analysis of univariate measures showed that Stage 1 humans did indeed possess the relatively shortest and most horizontally oriented CET's with the greatest amount of growth change occurring at the transition to Stage 2 (eruption of deciduous dentition at five postnatal months, commencing peak AOM incidence) and ceasing by Stage 3 (approximately six postnatal years). Skeletal indicators appear related to peak ages of AOM incidence and may contribute to understanding of a nearly ubiquitous human disease. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:1721-1740, 2017. © 2017 Wiley Periodicals, Inc.

Hearing sensitivity in adults with a unilateral cleft lip and palate after two-stage palatoplasty

OBJECTIVE

To evaluate long-term hearing and middle ear status in patients treated for a unilateral complete cleft lip and palate (UCLP) by two-stage palatoplasty.

METHODS

Forty-nine UCLP patients aged 17 years and older were included in this retrospective study. Patients were invited for a multidisciplinary long-term follow-up of their treatment at a tertiary center for craniofacial surgery in the Netherlands. ENT assessment included tympanometry and pure-tone audiometry. Medical files were searched for medical and surgical history.

RESULTS

In total, 19.4% of the patients had significant long-term hearing loss (PTA > 20 dB), comprising conductive hearing loss in 21.5% of the patients. In the majority (70%), this hearing loss was more pronounced at higher frequencies. In 25% the high fletcher index showed hearing thresholds above 20 dB. Ventilation tubes were placed at least once in 78.7% of the patients. The frequency of tube insertion was positively correlated with the incidence of reduced tympanic compliance (tympanogram type B) and the need for a pharyngoplasty.

CONCLUSION

The present study reports long-term hearing outcomes in UCLP patients with hard palate closure at 3 years of age. Persistent hearing loss was observed in 19.4% of our patients (PTA > 20 dB), mainly at the higher frequencies. Ventilation tube placement was associated with reduced tympanic compliance and higher risk on hearing loss (PTA air conduction). Our high incidence of velopharyngeal incompetence during early childhood, which is likely associated with Eustachian tube dysfunction, might have contributed to these results.

Craniofacial shape in children with and without a positive otitis media history

OBJECTIVES

Past studies using traditional morphometric approaches have reported a handful of differences in craniofacial dimensions between individuals with and without otitis media (OM). In this study, a geometric morphometry (GM) approach was used to determine if craniofacial shape is different among children with no history of OM and a history of recurrent acute OM (RAOM) at two different ages.

METHODS

Nineteen standard landmarks were identified on lateral cephalometric radiographs from 79 children (41 Control, 38 RAOM) at 4 years and 52 children (27 Control, 25 RAOM) at 6 years of age. Following Procrustes superimposition of the landmark coordinate data, comparisons of group differences in overall size and shape were performed. Discriminant function analysis and principal component analysis were used to determine which, if any, aspects of shape variation distinguished RAOM from Control groups.

RESULTS

At 4 years of age, craniofacial size and shape were significantly different between RAOM and Control groups (p<0.05). Shape differences were evident in the relative positions of the mandible, cranial base, external acoustic meatus, sphenoid and palate. Those shape differences were not found in the 6-year old group.

CONCLUSIONS

At 4 years of age, the RAOM and Control groups have distinct craniofacial morphologies, but by 6 years of age these differences have largely disappeared. This is consistent with the clinical observation that excess RAOM risk resolves around 6 years of age and the hypothesis that this resolution is partially a result of age-related craniofacial changes.

Do the angle and length of the eustachian tube influence the development of chronic otitis media?

OBJECTIVES/HYPOTHESIS

To compare the eustachian tube (ET) angle (ETa) and length (ETl) of ears with and without chronic otitis media (COM), and to determine the relationship between ET anatomy and the development of COM.

STUDY DESIGN

A retrospective case-control study.

METHODS

The study group comprised 125 patients (age range, 8-79 years; 64 males and 61 females) with 124 normal ears and 126 diseased ears, including ears with chronic suppurative otitis media (CSOM) with central perforation, intratympanic tympanosclerosis (ITTS), cholesteatoma, and a tympanic membrane with retraction pockets (TMRP). ET angle and length were measured using computed tomography employing the multiplanar reconstruction technique.

RESULTS

The ETa was significantly more horizontal in diseased versus normal ears of all study groups (P = .030), and there was no group difference in ETl (P = .160). ETl was shorter in CSOM versus ITTS ears and normal ears (P = .007 and P = .003, respectively) and in cholesteatoma versus TMRP ears (P = .014). In the unilateral COM group, there were no significant differences in the ETa or ETl of diseased versus contralateral normal ears (P = .155 and P = .710, respectively). The ETa was significantly more horizontal in childhood-onset diseased versus normal ears (P = .027), and there was no group difference in ETl (P = .732). The ETa (P = .002) and ETl (P < .001) were significantly greater in males than females.

CONCLUSIONS

A more horizontal ETa and shorter ETl could be contributory (though not significantly) etiological factors in the development of COM.

LEVEL OF EVIDENCE

3b.

Eustachian tube function in young children without a history of otitis media evaluated using a pressure chamber protocol

CONCLUSIONS

Protocol limitations were identified and accounted for in the analysis. Percent gradient equilibrated (PGE) was affected by driving gradient direction in a similar manner to other efficiency measures. A finer resolution of possible age-related changes in eustachian tube opening efficiency is expected with the application of more sophisticated statistical models to the complete dataset at study end.

OBJECTIVE

To report the results of an interim analysis for an ongoing study designed to characterize the age-related changes in eustachian tube opening efficiency measured using a pressure chamber protocol in children without a history of middle ear disease.

METHODS

To date, 41 children aged 3 years without a history of otitis media have been enrolled in a longitudinal study of the age-related changes in eustachian tube function and evaluated at yearly intervals between 3 and 7 years of age. Eustachian tube opening efficiency, the percent of the applied pressure gradient equilibrated by swallowing, was measured by repeat tympanometry during a pressure chamber protocol. Data (120 tests) were analyzed using an ANOVA with variance partitioned by age (3 through 6 years), gradient direction (positive/negative), and ear (left/right).

RESULTS

PGE was higher for left ears and positive driving gradients, but was not different among age groups.

Sensitivity and specificity of eustachian tube function tests in adults

IMPORTANCE

The study demonstrates the utility of eustachian tube (ET) function (ETF) test results for accurately assigning ears to disease state.

OBJECTIVES

To determine if ETF tests can identify ears with physician-diagnosed ET dysfunction (ETD) in a mixed population at high sensitivity and specificity and to define the interrelatedness of ETF test parameters.

DESIGN, SETTING, AND PARTICIPANTS

Through use of the forced-response, inflation-deflation, Valsalva, and sniffing tests, ETF was evaluated in 15 control ears of adult subjects after unilateral myringotomy (group 1) and in 23 ears of 19 adult subjects with ventilation tubes inserted for ETD (group 2). Data were analyzed using logistic regression including each parameter independently and then a step-down discriminant analysis including all ETF test parameters to predict group assignment. Factor analysis operating over all parameters was used to explore relatedness.

EXPOSURES

ETF testing.

MAIN OUTCOMES AND MEASURES

ETF parameters for the forced response, inflation-deflation, Valsalva, and sniffing tests measured in 15 control ears of adult subjects after unilateral myringotomy (group 1) and in 23 ears of 19 adult subjects with ventilation tubes inserted for ETD (group 2).

RESULTS

The discriminant analysis identified 4 ETF test parameters (Valsalva, ET opening pressure, dilatory efficiency, and percentage of positive pressure equilibrated) that together correctly assigned ears to group 2 at a sensitivity of 95% and a specificity of 83%. Individual parameters representing the efficiency of ET opening during swallowing showed moderately accurate assignments of ears to their respective groups. Three factors captured approximately 98% of the variance among parameters: the first had negative loadings of the ETF structural parameters; the second had positive loadings of the muscle-assisted ET opening parameters; and the third had negative loadings of the muscle-assisted ET opening parameters and positive loadings of the structural parameters.

CONCLUSIONS AND RELEVANCE

These results show that ETF tests can correctly assign individual ears to physician-diagnosed ETD with high sensitivity and specificity and that ETF test parameters can be grouped into structural-functional categories.

Otitis media and ear tubes

The placement of myringotomy tubes remains an effective treatment of recurrent acute otitis media and chronic otitis media with effusion. Infants and young children are prone to these entities because of their immature anatomy and immunology. Several host, pathogenic, and environmental factors contribute to the development of these conditions. The identification and modification of some these factors can preclude the need for intervention. The procedure continues to be one of the most common outpatient pediatric procedures. Close vigilance and identification of potential complications is of utmost importance in the ongoing management of the child with middle ear disease.

Eustachian tube function as a predictor of the recurrence of middle ear effusion in children

OBJECTIVES/HYPOTHESIS

In children with ventilation tubes (VTs) inserted for chronic otitis media with effusion (COME), the authors sought to determine whether any parameter of Eustachian tube (ET) function measured by the forced response test (FRT) predicts disease recurrence after the VT becomes nonfunctional.

STUDY DESIGN

Prospective study of those factors that predict disease recurrence in children with VTs inserted for COME.

METHODS

Forty-nine subjects (73 ears; 28 male, 34 white, aged 5.3 ± 1.2 years) with COME had VTs inserted and were evaluable for disease status after the VT(s) became nonfunctional. The FRT was done when the VTs were patent, and results for the last test before the VT became nonfunctional were used in the analysis. After each VT became nonfunctional, the children were followed for disease recurrence over a 12-month period. Logistic regression was used to determine whether the ET opening pressure, closing pressure, and/or dilatory efficiency predicted disease recurrence. That model was expanded to include age, sex, race, history of adenoidectomy, previous VTs, and duration of VT patency as potential predictive factors.

RESULTS

Twenty-nine (40%) ears had recurrence of significant disease within 12 months after the VT became nonfunctional. For the complete logistic regression model, male gender (P = .03), nonwhite race (P = .02), shorter period of VT patency (P = .01), and low dilatory efficiency (P = .01) were significant predictors of disease recurrence.

CONCLUSIONS

A measure of active ET function, dilatory efficiency, but not measures of passive function predicted disease recurrence within the 12 months after the VT became nonfunctional in children with COME.

Panel 2

Objective

This report reviews the literature to identify the advances in our understanding of the middle ear (ME)–Eustachian tube (ET) system during the past 4 years and, on that basis, to determine whether the short-term goals elaborated in the last report were achieved and propose updated goals to guide future otitis media (OM) research.

Data Sources

Databases searched included PubMed, Web of Science (1945-present), Medline (1950 to present), Biosis Previews (1969-present), and the Zoological Record (1978 to present). The initial literature search covered the time interval from January 2007 to June 2011, with a supplementary search completed in February 2012.

Review Methods

The panel topic was subdivided; each contributor performed a literature search and provided a preliminary report. Those reports were consolidated and discussed when the panel met on June 9, 2011. At that meeting, the progress was evaluated and new short-term goals proposed.

Conclusions

Progress was made on 16 of the 19 short-term goals proposed in 2007. Significant advances were made in the characterization of ME gas exchange pathways, modeling ET function, and preliminary testing of treatments for ET dysfunction.

Implications for Practice

In the future, imaging technologies should be developed to noninvasively assess ME/ET structure and physiology with respect to their role in OM pathogenesis. The new data derived from form/function experiments should be integrated into the finite element models and used to develop specific hypotheses concerning OM pathogenesis and persistence. Finally, rigorous studies of treatments, medical or surgical, of ET dysfunction should be undertaken.

The Cephalic Index is not different among groups of children aged 36-48 months with chronic otitis media with effusion, recurrent acute otitis media and controls

OBJECTIVES

The Cephalic Index, an anthropometric measure of head shape, was reported to be different between individuals with and without signs of past or concurrent otitis media (OM). In this study, we compared the Cephalic Index and other measures of head shape among groups of children aged 36-48 months with a documented history of chronic OM with effusion (COME), recurrent acute OM (RAOM) and CONTROLS (few to no OM episodes) to test that hypothesis.

METHODS

In 41 CONTROL, 36 COME and 42 RAOM children, Maximum Head Width, Maximum Head Length and Head Circumference were measured and the Cephalic Index (Head Width/Head Length×100) was calculated. The four measures were compared among the three groups using a General Linear Model that included group, sex and race as factors and age as a covariate.

RESULTS

There were no differences among groups in the Cephalic Index or Head Length. Head Width was significantly smaller in the RAOM when compared to the CONTROL group and Head Circumference was significantly smaller in the RAOM and COME groups when compared to the CONTROL group. For all measures, the distribution of values showed significant overlap among groups.

CONCLUSIONS

These results do not support the hypothesis that the Cephalic Index is different between young children with and without OM, but did document differences in Head Width and Circumference among groups. However, the large overlap in each measure for the three groups suggests that none capture sufficient information on Eustachian tube anatomy to predict disease presentation.

Sh3pxd2b mice are a model for craniofacial dysmorphology and otitis media

Craniofacial defects that occur through gene mutation during development increase vulnerability to eustachian tube dysfunction. These defects can lead to an increased incidence of otitis media. We examined the effects of a mutation in the Sh3pxd2b gene (Sh3pxd2b^nee) on the progression of otitis media and hearing impairment at various developmental stages. We found that all mice that had the Sh3pxd2b^nee mutation went on to develop craniofacial dysmorphologies and subsequently otitis media, by as early as 11 days of age. We found noteworthy changes in cilia and goblet cells of the middle ear mucosa in Sh3pxd2b^nee mutant mice using scanning electronic microscopy. By measuring craniofacial dimensions, we determined for the first time in an animal model that this mouse has altered eustachian tube morphology consistent with a more horizontal position of the eustachian tube. All mutants were found to have hearing impairment. Expression of TNF-α and TLR2, which correlates with inflammation in otitis media, was up-regulated in the ears of mutant mice when examined by immunohistochemistry and semi-quantitative RT-PCR. The mouse model with a mutation in the Sh3pxd2b gene (Sh3pxd2b^nee) mirrors craniofacial dysmorphology and otitis media in humans.