Prevalence of middle ear effusion in French bulldogs without clinical signs of otic disease: A retrospective study of magnetic resonance imaging (2017-2022).

BACKGROUND: Canine middle ear effusion (MEE) is usually asymptomatic, being an incidental finding when computed tomography or magnetic resonance imaging (MRI) of the head is performed for other reasons unrelated to otic disease. The clinical relevance of the presence of material in the tympanic bulla (TB) remains uncertain, and more detail about its prevalence and appearance in MRI are required. OBJECTIVE: To assess the prevalence of presence of material within the TB of French bulldogs (FB) with no clinical signs suggestive of otitis (externa, media or interna) that underwent high-field MRI for other medical reasons. ANIMALS: Two hundred fifty-two TB of 126 FB were included in this study. MATERIALS AND METHODS: Nonexperimental retrospective study in which MRI images were evaluated by a board-certified veterinary radiologist. RESULTS: Fifty-eight per cent of the dogs had material in the TB lumen (46% of the TB) and 59% were bilaterally affected. The signal intensity of this material related to the grey matter was variable on T1w and mainly hyperintense on T2w sequences. CONCLUSION AND CLINICAL RELEVANCE: FB are predisposed to MEE. This is important when assessing imaging studies of TB of FB with chronic otitis externa, as high percentage of cases may have concurrent MEE. MRI findings in FB with MEE are characterised by a hyperintense signal to the grey matter on T2w in most cases and variable on T1w sequences.

Quantitative transmastoid ultrasound for detecting middle ear effusion in pediatric patients.

BACKGROUND AND OBJECTIVE: Ultrasound has emerged as a promising modality for detecting middle ear effusion (MEE) in pediatric patients. Among different ultrasound techniques, ultrasound mastoid measurement was proposed to allow noninvasive detection of MEE by estimating the Nakagami parameters of backscattered signals to describe the echo amplitude distribution. This study further developed the multiregional-weighted Nakagami parameter (MNP) of the mastoid as a new ultrasound signature for assessing effusion severity and fluid properties in pediatric patients with MEE. METHODS: A total of 197 pediatric patients (n = 133 for the training group; n = 64 for the testing group) underwent multiregional backscattering measurements of the mastoid for estimating MNP values. MEE, the severity of effusion (mild to moderate vs. severe), and the fluid properties (serous and mucous) were confirmed through otoscopy, tympanometry, and grommet surgery and were compared with the ultrasound findings. The diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUROC). RESULTS: The training dataset revealed significant differences in MNPs between the control and MEE groups, between mild to moderate and severe MEE, and between serous and mucous effusion were observed (p < 0.05). As with the conventional Nakagami parameter, the MNP could be used to detect MEE (AUROC: 0.87; sensitivity: 90.16%; specificity: 75.35%). The MNP could further identify effusion severity (AUROC: 0.88; sensitivity: 73.33%; specificity: 86.87%) and revealed the possibility of characterizing fluid properties (AUROC: 0.68; sensitivity: 62.50%; specificity: 70.00%). The testing results demonstrated that the MNP method enabled MEE detection (AUROC = 0.88, accuracy = 88.28%, sensitivity = 92.59%, specificity = 84.21%), was effective in assessing MEE severity (AUROC = 0.83, accuracy = 77.78%, sensitivity = 66.67%, specificity = 83.33%), and showed potential for characterizing fluid properties of effusion (AUROC = 0.70, accuracy = 72.22%, sensitivity = 62.50%, specificity = 80.00%). CONCLUSIONS: Transmastoid ultrasound combined with the MNP not only leverages the strengths of the conventional Nakagami parameter for MEE diagnosis but also provides a means to assess MEE severity and effusion properties in pediatric patients, thereby offering a comprehensive approach to noninvasive MEE evaluation.

A deep learning approach to the diagnosis of atelectasis and attic retraction pocket in otitis media with effusion using otoscopic images.

BACKGROUND: This study aimed to develop and validate a deep learning (DL) model to identify atelectasis and attic retraction pocket in cases of otitis media with effusion (OME) using multi-center otoscopic images. METHOD: A total of 6393 OME otoscopic images from three centers were used to develop and validate a DL model for detecting atelectasis and attic retraction pocket. A threefold random cross-validation procedure was adopted to divide the dataset into training validation sets on a patient level. A team of otologists was assigned to diagnose and characterize atelectasis and attic retraction pocket in otoscopic images. Receiver operating characteristic (ROC) curves, including area under the ROC curve (AUC), accuracy, sensitivity, and specificity were used to assess the performance of the DL model. Class Activation Mapping (CAM) illustrated the discriminative regions in the otoscopic images. RESULTS: Among all OME otoscopic images, 3564 (55.74%) were identified with attic retraction pocket, and 2460 (38.48%) with atelectasis. The diagnostic DL model of attic retraction pocket and atelectasis achieved a threefold cross-validation accuracy of 89% and 79%, AUC of 0.89 and 0.87, a sensitivity of 0.93 and 0.71, and a specificity of 0.62 and 0.84, respectively. Larger and deeper cases of atelectasis and attic retraction pocket showed greater weight, based on the red color depicted in the heat map of CAM. CONCLUSION: The DL algorithm could be employed to identify atelectasis and attic retraction pocket in otoscopic images of OME, and as a tool to assist in the accurate diagnosis of OME.

[Ultrasound regional lymphotropic therapy for protracted forms of serous otitis media]. / Ul'trazvukovaya regionarnaya limfotropnaya terapiya pri zatyanuvshemsya techenii ekssudativnogo srednego otita.

The article is devoted to the clinical substantiation of the effectiveness of ultrasound regional lymphotropic therapy in protracted forms of serous otitis media (SOM). OBJECTIVE: To improve the method of conservative treatment of patients with protracted forms of SOM by clinically substantiating and developing a method of ultrasound regional lymphotropic therapy. MATERIAL AND METHODS: The study included 75 patients (102 cases of diseased ears) with SOM. Previously, they repeatedly underwent outpatient courses of conservative treatment for 1 to 3 months, but all had symptoms of the disease. In the department of otorhinolaryngology, each of the patients with protracted forms of SOM was given a course of ultrasound regional lymphotropic therapy. The criteria of the treatment results were subjective and objective data of a special examination, which included: the presence of relevant complaints, otoscopy, determination of the levels of perception of live speech, indicators of air and bone sound conduction, tonal threshold audiometry, tympanometry characterizing the dynamics of hearing, the airiness of the tympanic cavity, the functioning of the auditory tubes. The examination was performed before and after treatment. RESULTS: Confirmation of the effectiveness of ultrasound regional lymphotropic therapy in protracted forms of SOM was the restoration in 52% of patients of whispering and in 68% of patients of colloquial speech to socially adequate values; a decrease in the level of sound perception thresholds at all frequencies by air conduction; an increase in tonal hearing; a complete restoration of the airiness of the tympanic cavity in 57% of patients (type A tympanogram). CONCLUSION: A new method of treating patients with protracted forms of SOM has been developed and clinically justified by the combined use of low-frequency ultrasound and medications with lymphotropic effect.

A Deep Learning Approach to Predict Conductive Hearing Loss in Patients With Otitis Media With Effusion Using Otoscopic Images.

Importance: Otitis media with effusion (OME) is one of the most common causes of acquired conductive hearing loss (CHL). Persistent hearing loss is associated with poor childhood speech and language development and other adverse consequence. However, to obtain accurate and reliable hearing thresholds largely requires a high degree of cooperation from the patients. Objective: To predict CHL from otoscopic images using deep learning (DL) techniques and a logistic regression model based on tympanic membrane features. Design, Setting, and Participants: A retrospective diagnostic/prognostic study was conducted using 2790 otoscopic images obtained from multiple centers between January 2015 and November 2020. Participants were aged between 4 and 89 years. Of 1239 participants, there were 209 ears from children and adolescents (aged 4-18 years [16.87%]), 804 ears from adults (aged 18-60 years [64.89%]), and 226 ears from older people (aged >60 years, [18.24%]). Overall, 679 ears (54.8%) were from men. The 2790 otoscopic images were randomly assigned into a training set (2232 [80%]), and validation set (558 [20%]). The DL model was developed to predict an average air-bone gap greater than 10 dB. A logistic regression model was also developed based on otoscopic features. Main Outcomes and Measures: The performance of the DL model in predicting CHL was measured using the area under the receiver operating curve (AUC), accuracy, and F1 score (a measure of the quality of a classifier, which is the harmonic mean of precision and recall; a higher F1 score means better performance). In addition, these evaluation parameters were compared to results obtained from the logistic regression model and predictions made by three otologists. Results: The performance of the DL model in predicting CHL showed the AUC of 0.74, accuracy of 81%, and F1 score of 0.89. This was better than the results from the logistic regression model (ie, AUC of 0.60, accuracy of 76%, and F1 score of 0.82), and much improved on the performance of the 3 otologists; accuracy of 16%, 30%, 39%, and F1 scores of 0.09, 0.18, and 0.25, respectively. Furthermore, the DL model took 2.5 seconds to predict from 205 otoscopic images, whereas the 3 otologists spent 633 seconds, 645 seconds, and 692 seconds, respectively. Conclusions and Relevance: The model in this diagnostic/prognostic study provided greater accuracy in prediction of CHL in ears with OME than those obtained from the logistic regression model and otologists. This indicates great potential for the use of artificial intelligence tools to facilitate CHL evaluation when CHL is unable to be measured.

Shortwave infrared otoscopy for diagnosis of middle ear effusions: a machine-learning-based approach.

Otitis media, a common disease marked by the presence of fluid within the middle ear space, imparts a significant global health and economic burden. Identifying an effusion through the tympanic membrane is critical to diagnostic success but remains challenging due to the inherent limitations of visible light otoscopy and user interpretation. Here we describe a powerful diagnostic approach to otitis media utilizing advancements in otoscopy and machine learning. We developed an otoscope that visualizes middle ear structures and fluid in the shortwave infrared region, holding several advantages over traditional approaches. Images were captured in vivo and then processed by a novel machine learning based algorithm. The model predicts the presence of effusions with greater accuracy than current techniques, offering specificity and sensitivity over 90%. This platform has the potential to reduce costs and resources associated with otitis media, especially as improvements are made in shortwave imaging and machine learning.

Analysing wideband absorbance immittance in normal and ears with otitis media with effusion using machine learning.

Wideband Absorbance Immittance (WAI) has been available for more than a decade, however its clinical use still faces the challenges of limited understanding and poor interpretation of WAI results. This study aimed to develop Machine Learning (ML) tools to identify the WAI absorbance characteristics across different frequency-pressure regions in the normal middle ear and ears with otitis media with effusion (OME) to enable diagnosis of middle ear conditions automatically. Data analysis included pre-processing of the WAI data, statistical analysis and classification model development, and key regions extraction from the 2D frequency-pressure WAI images. The experimental results show that ML tools appear to hold great potential for the automated diagnosis of middle ear diseases from WAI data. The identified key regions in the WAI provide guidance to practitioners to better understand and interpret WAI data and offer the prospect of quick and accurate diagnostic decisions.

Deep metric learning for otitis media classification.

In this study, we propose an automatic diagnostic algorithm for detecting otitis media based on otoscopy images of the tympanic membrane. A total of 1336 images were assessed by a medical specialist into three diagnostic groups: acute otitis media, otitis media with effusion, and no effusion. To provide proper treatment and care and limit the use of unnecessary antibiotics, it is crucial to correctly detect tympanic membrane abnormalities, and to distinguish between acute otitis media and otitis media with effusion. The proposed approach for this classification task is based on deep metric learning, and this study compares the performance of different distance-based metric loss functions. Contrastive loss, triplet loss and multi-class N-pair loss are employed, and compared with the performance of standard cross-entropy and class-weighted cross-entropy classification networks. Triplet loss achieves high precision on a highly imbalanced data set, and the deep metric methods provide useful insight into the decision making of a neural network. The results are comparable to the best clinical experts and paves the way for more accurate and operator-independent diagnosis of otitis media.

Longitudinal optical coherence tomography to visualize the in vivo response of middle ear biofilms to antibiotic therapy.

Studying the impact of antibiotic treatment on otitis media (OM), the leading cause of primary care office visits during childhood, is critical to develop appropriate treatment strategies. Tracking dynamic middle ear conditions during antibiotic treatment is not readily applicable in patients, due to the limited diagnostic techniques available to detect the smaller amount and variation of middle ear effusion (MEE) and middle ear bacterial biofilm, responsible for chronic and recurrent OM. To overcome these challenges, a handheld optical coherence tomography (OCT) system has been developed to monitor in vivo response of biofilms and MEEs in the OM-induced chinchilla model, the standard model for human OM. As a result, the formation of MEE as well as biofilm adherent to the tympanic membrane (TM) was longitudinally assessed as OM developed. Various types of MEEs and biofilms in the chinchilla model were identified, which showed comparable features as those in humans. Furthermore, the effect of antibiotics on the biofilm as well as the amount and type of MEEs was investigated with low-dose and high-dose treatment (ceftriaxone). The capability of OCT to non-invasively track and examine middle ear conditions is highly beneficial for therapeutic OM studies and will lead to improved management of OM in patients.

Assessment of radiation-induced otitis media in patients with parotid gland malignancy.

BACKGROUND: Otitis media with effusion (OME) is a known side effect of radiation therapy in patients with head and neck cancer. AIMS/OBJECTIVES: To investigate the incidence rate and clinical course of radiation-induced OME, we have reported on the long-term characteristics of OME in patients with parotid gland malignancy. MATERIAL AND METHODS: This cohort study assessed 200 patients who underwent post-parotidectomy radiation therapy from January 2010 to December 2019 in a tertiary referral center. Postoperative radiation therapy was performed at 6 weeks post-surgery. Serial magnetic resonance images were collected to detect otitis media. Two blinded otologists individually assessed data from radiation therapy initiation to 36 months of post-radiation therapy. RESULTS: A total of 121 patients were enrolled (male, 61 [50.4%]; mean age, 46.98 ± 15.69 years), of which 14 developed otitis media (11.6%) within 6 months after radiation therapy. Spontaneous remission occurred without intervention within 1 year, excluding one patient who sustained otitis media for 2 years. CONCLUSIONS AND SIGNIFICANCE: Radiation-induced OME occurred in 11.6% of patients and it remitted within 1 year without intervention. Therefore, cooperation between otolaryngologists and radiation oncologists is required and invasive intervention should be considered with careful risk-benefit evaluation.

Influence of computed tomographic dimensions of the nasopharynx on middle ear effusion and inflammation in pugs and French bulldogs with brachycephalic airway syndrome.

OBJECTIVE: To compare the prevalence of middle ear abnormalities in pugs and in French bulldogs and evaluate the influence of nasopharyngeal dimensions on middle ear effusion. STUDY DESIGN: Retrospective study. ANIMALS: Thirty pugs and 30 French bulldogs with brachycephalic airway syndrome and no known history of ear disease. METHODS: Computed tomographic (CT) studies were reviewed for middle ear effusion, mucosal contrast enhancement, signs of osteitis, and tympanic wall thickness. Soft palate thickness and cross-sectional areas of the nasopharynx at the opening of the auditory tube were measured and normalized to each individual's skull index before statistical comparison between breeds. Statistical dependence of middle ear abnormalities and nasopharyngeal dimensions was assessed by using Spearman's rank correlation tests. RESULTS: Middle ear effusion was observed in 17 of 30 (56.7%) French bulldogs and five of 30 (16.7%) pugs. Contrast enhancement of the tympanic bulla was noted in 25 of 60 (41.6%) French bulldog ears and three of 60 (5.0%) pug ears. The cross-sectional airway dimensions (difference [Δ] = 0.31 cm2 , P < .0001) and soft palate thickness (Δ = 0.44 cm, P < .0001) were reduced in pugs compared with in French bulldogs. Weak correlations were detected between soft palate thickness and nasopharyngeal dimensions and presence of tympanic bulla effusion (r = 0.324 and r = 0.198, respectively) or contrast enhancement (r = 0.270 and r = 0.199, respectively). CONCLUSION: Middle ear effusion and inflammation were more common in French bulldogs than in pugs and did not seem related to nasopharyngeal dimensions. CLINICAL SIGNIFICANCE: French bulldogs with brachycephalic airway syndrome seem predisposed to middle ear effusion and inflammation.

The Feasibility of Magnetic Resonance Imaging for the Differentiation of Cerebrospinal Fluid Leak From Middle Ear Effusion: A Quantitative Analysis.

OBJECTIVE: Assess quantitatively whether magnetic resonance imaging (MRI) signal intensity can be used to distinguish cerebrospinal fluid (CSF) leaks in the temporal bone from middle ear effusions. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Forty-nine patients, 18 with middle ear effusions (MEE), 30 with CSF leaks, and 1 with an MEE on one side and a CSF leak on the other, were evaluated in the study. Primary inclusion criteria for CSF leak patients were operative management of CSF leak with confirmatory diagnosis in follow-up. Primary inclusion criteria for MEE patients were electronic medical record documentation of an effusion with subsequent resolution on follow-up. For all patients, inclusion criteria included MRI imaging with 3D-T2 weighted sequences (3DT2) and fluid-attenuated inversion recovery (FLAIR) sequences performed within 1 year of diagnosis code entry. INTERVENTION: Computational analysis of signal intensity of fluid collections in MRI imaging. MAIN OUTCOME MEASURES: Sensitivity and specificity of 3DT2 and FLAIR signal intensity in the detection of CSF leak. RESULTS: For 3DT2 sequences with a chosen normalized signal intensity threshold (CSF leak if ≥ 0.5), sensitivity was 100% (95% CI: 86.3-100) and specificity was 83.3% (95% CI: 51.6-97.9). For FLAIR sequences with a threshold of 1.0 (CSF leak if < 1.0), sensitivity was 77.4% (95% CI: 58.9-90.4) and specificity was 85.7% (95% CI: 63.6-97.0). For a combined test in which a fluid collection was considered CSF if both 3DT2 ≥ 0.5 and FLAIR < 1.0, sensitivity was 76% (95% CI: 54.9-90.6) and specificity was 100% (95% CI: 73.5-100).

Intradiploic Epidermoid Cyst Causing Otitis Media with Effusion: Case Report and Review of the Literature.

BACKGROUND: Epidermoid cysts are rare, slow-growing, benign tumors. They commonly occur at the cerebellopontine angle or the suprasellar region, and they can also occur in the skull. Intradiploic epidermoid cysts are often detected incidentally, but their progression can cause various symptoms. CASE DESCRIPTION: The patient was a 49-year-old woman who was diagnosed with otitis media with effusion based on a reported sensation of left ear blockage. Thorough examination revealed a mass lesion in the left occipital bone. Computed tomography depicted a mass lesion on the left occipital bone, part of which reached the inner table of the skull and eroded the mastoid air cell. On magnetic resonance imaging, T1-weighted signal was low but T2-weighted signal and diffusion-weighted signal were high. An intradiploic epidermoid cyst was suspected on the basis of imaging results, and it was surmised that mastoid cellulitis by the mass lesion accompanied by bone destruction had progressed to otitis media with effusion. The pathologic diagnosis was epidermoid cysts. Six months after the operation the otitis media with effusion had improved, and there had been no recurrence of epidermoid cysts. CONCLUSIONS: We experienced a case of occipital bone intradiploic epidermoid cysts diagnosed in conjunction with otitis media with effusion.

Cytological and microbiological characteristics of middle ear effusions in brachycephalic dogs.

BACKGROUND: Middle ear effusion is common in brachycephalic dogs with similarities to otitis media with effusion in children. Association with the cranial and eustachian tube morphology and bacterial infection is suspected in both species. HYPOTHESIS/OBJECTIVES: To determine cytological and bacteriological features of middle ear effusions in dogs, provide information on histological features, and further assess the dog as a model of the human disease. ANIMALS: Sixteen live dogs, 3 postmortem cases of middle ear effusion, and 2 postmortem controls. METHODS: Prospective; clinical investigation using computed tomography, magnetic resonance imaging, video-otoscopy, myringotomy; cytological assessment of 30 and bacteriology of 28 effusions; histology and immunohistochemistry (CD3 for T-lymphocytes, Pax5 for B lymphocytes and MAC387 for macrophages) of 10 middle ear sections. RESULTS: Effusions were associated with neurological deficits in 6/16 (38%) and concurrent atopic dermatitis and otitis externa in 9/16 (56%) of live cases. Neutrophils and macrophages predominated on cytology (median 60 [range 2%-95.5%] and 27 [2%-96.5%]) whether culture of effusions was positive or not. In histology sections, the mucosa was thickened in affected dogs but submucosal gland dilatation occurred in affected and unaffected dogs. There was no bacterial growth from 22/28 (79%) of effusions. Bacteria isolated from the other 6 (21%) were predominantly Staphylococcus pseudintermedius (4/6, 67%). CONCLUSIONS AND CLINICAL IMPORTANCE: Clinical, morphological, and cytological findings in middle ear effusions of dogs and people suggest similar pathogeneses. Middle ear effusion of dogs could be a useful model of human otitis media with effusion. Such comparisons can improve understanding and management across species.

Panel 8: Vaccines and immunology.

OBJECTIVE: To review and highlight significant advances made towards vaccine development and understanding of the immunology of otitis media (OM) since the 19th International Symposium on Recent Advances in Otitis Media (ISOM) in 2015, as well as identify future research directions and knowledge gaps. DATA SOURCES: PubMed database, National Library of Medicine. REVIEW METHODS: Key topics were assigned to each panel member for detailed review. Draft reviews were collated, circulated, and thoroughly discussed when the panel met at the 20th ISOM in June 2019. The final manuscript was prepared with input from all panel members. CONCLUSIONS: Since 2015 there have been a number of studies assessing the impact of licensed pneumococcal vaccines on OM. While these studies have confirmed that these vaccines are effective in preventing carriage and/or disease caused by vaccine serotypes, OM caused by non-vaccine serotype pneumococci and other otopathogens remains a significant health care burden globally. Development of multi-species vaccines is challenging but essential to reducing the global burden of OM. Influenza vaccination has been shown to prevent acute OM, and with novel vaccines against nontypeable Haemophilus influenzae (NTHi), Moraxella catarrhalis and Respiratory Syncytial Virus (RSV) in clinical trials, the potential to significantly prevent OM is within reach. Research into alternative vaccine delivery strategies has demonstrated the power of maternal and mucosal vaccination for OM prevention. Future OM vaccine trials must include molecular diagnostics of middle ear effusion, for detection of viruses and bacteria that are persisting in biofilms and to enable accurate assessment of vaccine impact on OM etiology. Understanding population differences in natural and vaccine-induced immune responses to otopathogens is also important for development of the most effective OM vaccines. Improved understanding of the interaction between otopathogens will also advance development of effective therapies and encourage the assessment of the indirect benefits of vaccination. IMPLICATIONS FOR PRACTICE: While NTHi and M. catarrhalis are the predominant otopathogens, funding opportunities to drive vaccine development for these species are limited due to a focus on prevention of childhood mortality rather than morbidity. Delivery of a comprehensive report on the high financial and social costs of OM, including the potential for OM vaccines to reduce antibiotic use and subsequent development of antimicrobial resistance (AMR), would likely assist in engaging stakeholders to recognize the value of prevention of OM and increase support for efforts on OM vaccine development. Vaccine trials with OM prevention as a clinical end-point are challenging, however a focus on developing assays that measure functional correlates of protection would facilitate OM vaccine development.

Panel 1: Biotechnology, biomedical engineering and new models of otitis media.

OBJECTIVE: To summarize recently published key articles on the topics of biomedical engineering, biotechnology and new models in relation to otitis media (OM). DATA SOURCES: Electronic databases: PubMed, Ovid Medline, Cochrane Library and Clinical Evidence (BMJ Publishing). REVIEW METHODS: Articles on biomedical engineering, biotechnology, material science, mechanical and animal models in OM published between May 2015 and May 2019 were identified and subjected to review. A total of 132 articles were ultimately included. RESULTS: New imaging technologies for the tympanic membrane (TM) and the middle ear cavity are being developed to assess TM thickness, identify biofilms and differentiate types of middle ear effusions. Artificial intelligence (AI) has been applied to train software programs to diagnose OM with a high degree of certainty. Genetically modified mice models for OM have further investigated what predisposes some individuals to OM and consequent hearing loss. New vaccine candidates protecting against major otopathogens are being explored and developed, especially combined vaccines, targeting more than one pathogen. Transcutaneous vaccination against non-typeable Haemophilus influenzae has been successfully tried in a chinchilla model. In terms of treatment, novel technologies for trans-tympanic drug delivery are entering the clinical domain. Various growth factors and grafting materials aimed at improving healing of TM perforations show promising results in animal models. CONCLUSION: New technologies and AI applications to improve the diagnosis of OM have shown promise in pre-clinical models and are gradually entering the clinical domain. So are novel vaccines and drug delivery approaches that may allow local treatment of OM. IMPLICATIONS FOR PRACTICE: New diagnostic methods, potential vaccine candidates and the novel trans-tympanic drug delivery show promising results, but are not yet adapted to clinical use.

Assessing the Effect of Middle Ear Effusions on Wideband Acoustic Immittance Using Optical Coherence Tomography.

OBJECTIVES: Wideband acoustic immittance (WAI) noninvasively assesses middle ear function by measuring the sound conduction over a range of audible frequencies. Although several studies have shown the potential of WAI for detecting the presence of middle ear effusions (MEEs), determining the effects of MEE type and amount on WAI in vivo has been challenging due to the anatomical location of middle ear cavity. The purpose of this study is to correlate WAI measurements with physical characteristics of the middle ear and MEEs determined by optical coherence tomography (OCT), a noninvasive optical imaging technique. DESIGN: Sixteen pediatric subjects (average age of 7 ± 4 years) were recruited from the primary care clinic at Carle Foundation Hospital (Urbana, IL). A total of 22 ears (normal: 15 ears, otitis media with effusion: 6 ears, and acute otitis media: 1 ear, based on physician's diagnosis) were examined via standard otoscopy, tympanometry, OCT imaging, and WAI measurements in a busy, community-based clinical setting. Cross-sectional OCT images were analyzed to quantitatively assess the presence, type (relative turbidity based on the amount of scattering), and amount (relative fluid level) of MEEs. These OCT metrics were utilized to categorize subject ears into no MEE (control), biofilm without a MEE, serous-scant, serous-severe, mucoid-scant, and mucoid-severe MEE groups. The absorbance levels in each group were statistically evaluated at α = 0.05. RESULTS: The absorbance of the control group showed a similar trend when compared with a pediatric normative dataset, and the presence of an MEE generally decreased the power absorbance. The mucoid MEE group showed significantly less power absorbance from 2.74 to 4.73 kHz (p < 0.05) when compared with the serous MEE group, possibly due to the greater mass impeding the middle ear system. Similarly, the greater amount of middle ear fluid contributed to the lower power absorbance from 1.92 to 2.37 kHz (p< 0.05), when compared with smaller amounts of fluid. As expected, the MEEs with scant fluid only significantly affected the power absorbance at frequencies greater than 4.85 kHz. A large variance in the power absorbance was observed between 2 and 5 kHz, suggesting the dependence on both the type and amount of MEE. CONCLUSIONS: Physical characteristics of the middle ear and MEEs quantified from noninvasive OCT images can be helpful to understand abnormal WAI measurements. Mucoid MEEs decrease the power absorbance more than serous MEEs, and the greater amounts of MEE decreases the power absorbance, especially at higher (>2 kHz) frequencies. As both the type and amount of MEE can significantly affect WAI measurements, further investigations to correlate acoustic measurements with physical characteristics of middle ear conditions in vivo is needed.

Updates in Pediatric Cholesteatoma: Minimizing Intervention While Maximizing Outcomes.

Advances in pediatric otology have provided new tools to diagnose and manage complex otologic disease. Diffusion-weighted MRI provides the surgeon with a tool to detect recurrent or residual cholesteatoma that may obviate a second look surgery. Surgical trends move toward less invasive surgery. The literature provides good evidence to advocate for preserving the posterior ear canal and single stage ossiculoplasty. The growing popularity and increasing evidence in the literature supports otoendoscopy as a means to minimize invasiveness while eradicating disease in previously difficult to reach anatomic locations. These advances have allowed the otologic surgeon to improve surgical outcomes while minimizing intervention.

Utility of Magnetic Resonance Imaging in Differentiating Cerebrospinal Fluid Leak from Middle Ear Effusion.

OBJECTIVE: To demonstrate the clinical utility, sensitivity, and specificity of standard magnetic resonance imaging (MRI) sequences in differentiating temporal bone cerebrospinal fluid leaks from all other middle ear effusions. STUDY DESIGN: Retrospective imaging review. SETTING: Academic medical center. SUBJECTS: Patients with cerebrospinal fluid leaks or other middle ear effusions who also underwent MRI. METHODS: Patients were assigned to cerebrospinal fluid leak and other effusion cohorts based on clinical course, findings at surgery/myringotomy, and beta-2 transferrin fluid analysis. Reviewers blinded to the clinical outcome examined T1-weighted, T2-weighted, diffusion-weighted, fluid-attenuated inversion recovery (FLAIR), and 3-dimensional (3D) acquired T2-weighted MRI sequences. For each sequence, fluid imaged in the temporal bone was graded as either similar or dissimilar in signal intensity to cerebrospinal fluid in the adjacent subarachnoid space. Signal similarity was interpreted as being diagnostic of a leak. Test characteristics in predicting the presence of a leak were calculated for each series. RESULTS: Eighty patients met criteria (41 leaks, 39 other effusions). The 3D T2 series was 76% sensitive and 100% specific in diagnosing a leak, and FLAIR was 44% sensitive and 100% specific. The T1-weighted (73% sensitive, 69% specific), T2-weighted (98% sensitive, 5.1% specific), and diffusion-weighted (63% sensitive, 66% specific) series were less useful. CONCLUSIONS: MRI, with attention to 3D T2 and FLAIR series, is a noninvasive and highly specific test for diagnosing cerebrospinal fluid leak in the setting of an indeterminate middle ear effusion.

Eustachian Tube Function in Adults with Ventilation Tubes Inserted for Otitis Media with Effusion.

OBJECTIVE: To investigate the eustachian tube (ET) function (ETF) in adults with ventilation tube (VT) inserted for the treatment of chronic otitis media with effusion (COME). MATERIALS AND METHODS: A total of 17 subjects with at least one VT were enrolled. A detailed history was obtained, and risk factors were assessed with questionnaires. Examination including nasopharyngeal video endoscopy and ETF tests, the forced response test (FRT), inflation-deflation test (IDT), and nasal/nasopharyngeal maneuvers (such as sniffing and Valsalva, Toynbee, and the diver's maneuvers) were performed. RESULTS: Averages for FRT were 580±333 daPa, 382±251 daPa, and 138±192 daPa for opening pressure, steady-state pressure, and closing pressure, respectively. Most subjects demonstrated minimal or weak active function during the FRT and IDT. While nasopharyngeal maneuvers changed the nasal/nasopharyngeal pressures, they did not significantly change the middle-ear pressures. These results indicated that most subjects had severe obstructive ET dysfunction (ETD) with an ET lumen that required high pressure differences to open and poor active muscular function inadequate for luminal dilation. These results imply that while any treatment to widen the ET, such as balloon dilation of the ET, is not expected to change the voluntary active muscular function, it may reduce the tissue pressures and resistance, thus facilitating luminal opening both passively and actively. CONCLUSION: Most patients with VT inserted for the treatment of COME appear to have an abnormal ETF with difficulty in passively opening the ET and weak active muscular function. Management of such patients addressing only passive properties may not be sufficient for the resolution of ETD.