Material characterization of human middle ear using machine-learning-based surrogate models

This study aims to introduce a novel non-invasive method for rapid material characterization of middle-ear structures, taking into consideration the invaluable insights provided by the mechanical properties of ear tissues. Valuable insights into various ear pathologies can be gleaned from the mechanical properties of ear tissues, yet conventional techniques for assessing these properties often entail invasive procedures that preclude their use on living patients. In this study, in the first step, we developed machine-learning models of the middle ear to predict its responses with a significantly lower computational cost in comparison to finite-element models. Leveraging findings from prior research, we focused on the most influential model parameters: the Young's modulus and thickness of the tympanic membrane and the Young's modulus of the stapedial annular ligament. The eXtreme Gradient Boosting (XGBoost) method was implemented for creating the machine-learning models. Subsequently, we combined the created machine-learning models with Bayesian optimization (BoTorch) for fast and efficient estimation of the Young's moduli of the tympanic membrane and the stapedial annular ligament. We demonstrate that the resultant surrogate models can fairly represent the vibrational responses of the umbo, stapes footplate, and vibration patterns of the tympanic membrane at most frequencies. Also, our proposed material characterization approach successfully estimated the Young's moduli of the tympanic membrane and stapedial annular ligament (separately and simultaneously) with values of mean absolute percentage error of less than 7%. The remarkable accuracy achieved through the proposed material characterization method underscores its potential for eventual clinical applications of estimating mechanical properties of the middle-ear structures for diagnostic purposes.

Comparison of side effects of different steroids used in intratympanic injections

OBJECTIVES

This study aimed to compare the side effects of different steroids used in the intratympanic injections (IT).

METHODS

One hundred and sixty patients diagnosed with sudden sensorineural hearing loss and undergoing IT were assigned to four groups based on the type or concentration of steroids administered (Group DM5: 5 mg/ml Dexamethasone sodium phosphate; Group DM10: 10 mg/ml Dexamethasone sodium phosphate; Group MP: 40 mg/ml Methylprednisolone sodium succinate; Group BM: 4 mg/ml Betamethasone sodium phosphate). Each group comprised 40 patients, and all participants received IT six times. The study assessed and compared the degrees and duration of pain, dizziness, and tympanic membrane damage following IT. Patients were asked to report the pain they felt using the numeric rating scale (NRS).

RESULTS

NRS scores for pain after IT showed significant differences among the four groups (p < 0.001). The average NRS scores for pain in each group were as follows: Group DM5: 1.53 ± 1.04; Group DM10: 1.45 ± 1.30; Group MP: 4.33 ± 2.22; Group BM: 6.03 ± 1.46. The durations of pain after IT also exhibited significant differences among the four groups (p < 0.001), with the longest duration observed in Group MP at 31.93 ± 15.20 min.

CONCLUSION

Different types of steroids could lead to varying degrees of pain when used in IT. Betamethasone could cause the most severe pain, and methylprednisolone could result in the longest duration of pain.

The importance of mechanical and biological cues of tympanic membrane grafts to ensure optimal regeneration

Chronic suppurative otitis media (CSOM) is often associated with permanent tympanic membrane (TM) perforation and conductive hearing loss. The current clinical gold standard, using autografts and allografts, suffers from several drawbacks. Artificial replacement materials can help to overcome these drawbacks. Therefore, scaffolds fabricated through digital light processing (DLP) were herein created to support TM regeneration. Various UV-curable printing inks, including gelatin methacryloyl (GelMA), gelatin-norbornene-norbornene (GelNBNB) (crosslinked with thiolated gelatin (GelSH)) and alkene-functionalized poly-ε-caprolactone (E-PCL) (crosslinked with pentaerythritol tetrakis(3-mercaptopropionate) (PETA4SH)) were optimized regarding photo-initiator (PI) and photo-absorber (PA) concentrations through viscosity characterization, photo-rheology and the establishment of working curves for DLP. Our material platform enabled the development of constructs with a range of mechanical properties (plateau storage modulus varying between 15 and 119 kPa). Excellent network connectivity for the GelNBNB and E-PCL constructs was demonstrated (gel fractions >95 %) whereas a post-crosslinking step was required for the GelMA constructs. All samples showed excellent biocompatibility (viability >93 % and metabolic activity >88 %). Finally, in vivo and ex vivo assessments, including histology, vibration and deformation responses measured through laser doppler vibrometry and digital image correlation respectively, were performed to investigate the effects of the scaffolds on the anatomical and physiological regeneration of acute TM perforations in rabbits. The data showed that the most efficient healing with the best functional quality was obtained when both mechanical (obtained with the PCL-based resin) and biological (obtained with the gelatin-based resins) material properties were taken into account.

Development and Validation of an Automated Classifier to Diagnose Acute Otitis Media in Children

Importance

Acute otitis media (AOM) is a frequently diagnosed illness in children, yet the accuracy of diagnosis has been consistently low. Multiple neural networks have been developed to recognize the presence of AOM with limited clinical application.

Objective

To develop and internally validate an artificial intelligence decision-support tool to interpret videos of the tympanic membrane and enhance accuracy in the diagnosis of AOM.

Design, Setting, and Participants

This diagnostic study analyzed otoscopic videos of the tympanic membrane captured using a smartphone during outpatient clinic visits at 2 sites in Pennsylvania between 2018 and 2023. Eligible participants included children who presented for sick visits or wellness visits.

Exposure

Otoscopic examination.

Main Outcomes and Measures

Using the otoscopic videos that were annotated by validated otoscopists, a deep residual-recurrent neural network was trained to predict both features of the tympanic membrane and the diagnosis of AOM vs no AOM. The accuracy of this network was compared with a second network trained using a decision tree approach. A noise quality filter was also trained to prompt users that the video segment acquired may not be adequate for diagnostic purposes.

Results

Using 1151 videos from 635 children (majority younger than 3 years of age), the deep residual-recurrent neural network had almost identical diagnostic accuracy as the decision tree network. The finalized deep residual-recurrent neural network algorithm classified tympanic membrane videos into AOM vs no AOM categories with a sensitivity of 93.8% (95% CI, 92.6%-95.0%) and specificity of 93.5% (95% CI, 92.8%-94.3%) and the decision tree model had a sensitivity of 93.7% (95% CI, 92.4%-94.9%) and specificity of 93.3% (92.5%-94.1%). Of the tympanic membrane features outputted, bulging of the TM most closely aligned with the predicted diagnosis; bulging was present in 230 of 230 cases (100%) in which the diagnosis was predicted to be AOM in the test set.

Conclusions and Relevance

These findings suggest that given its high accuracy, the algorithm and medical-grade application that facilitates image acquisition and quality filtering could reasonably be used in primary care or acute care settings to aid with automated diagnosis of AOM and decisions regarding treatment.

Bacterial Cellulose Electrospun Fiber Mesh Coated with Chitin Nanofibrils for Eardrum Repair

In this study, we develop a bio-based and bioactive nanofibrous patch based on bacterial cellulose (BC) and chitin nanofibrils (CNs) using an ionic liquid as a solvent for BC, aimed at tympanic membrane (TM) repair. Electrospun BC nanofiber meshes were produced via electrospinning, and surface-modified with CNs using electrospray. The rheology of the BC/ionic liquid system was investigated. The obtained CN/BC meshes underwent comprehensive morphological, physicochemical, and mechanical characterization. Cytotoxicity tests were conducted using L929 mouse fibroblasts, revealing a cell viability of 97.8%. In vivo tests on rabbit skin demonstrated that the patches were nonirritating. Furthermore, the CN/BC fiber meshes were tested in vitro using human dermal keratinocytes (HaCaT cells) and human umbilical vein endothelial cells as model cells for TM perforation healing. Both cell types demonstrated successful growth on these scaffolds. The presence of CNs resulted in improved indirect antimicrobial activity of the electrospun fiber meshes. HaCaT cells exhibited an upregulated mRNA expression at 6 and 24 h of key proinflammatory cytokines crucial for the wound healing process, indicating the potential benefits of CNs in the healing response. Overall, this study presents a natural and eco-sustainable fiber mesh with great promise for applications in TM repair, leveraging the synergistic effects of BC and CNs to possibly enhance tissue regeneration and healing. Impact statement Repair of tympanic membrane perforations following chronic otitis media is a main clinical issue in otologic surgery, where the underlying infection obstacles self-healing. To address this challenge, our study proposes a bio-based patch made of nanoscale carbohydrate materials (i.e., bacterial cellulose electrospun fibers and chitin nanofibrils) processed via green solvents. The scaffold is nonirritating in vivo, and cytocompatible with fibroblasts, endothelial cells, and keratinocytes. In epithelial cells, it stimulates the expression of the antimicrobial peptide human beta defensin 2, with a pathway of cytokine expression compatible with the wound healing process. Therefore, it could be applied with unsolved infective pathology.

Outcomes of regenerative treatment for over 200 patients with tympanic membrane perforation

OBJECTIVE

To evaluate outcomes of a regenerative treatment (RT) for over 200 patients with tympanic membrane perforation (TMP). The RT-TMP method involves a gelatin sponge, basic fibroblast growth factor (bFGF) and fibrin glue.

METHODS

The study population included 216 patients and 234 ears (male: female =100:116; age 1-93 years). All enrolled patients were treated with RT-TMP in which TMP edges were disrupted mechanically and a gelatin sponge immersed in bFGF was inserted into the perforation. Fibrin glue was then dripped over the sponge. Patient outcomes including TMP closure rates, change in hearing level, and complications were obtained from retrospective medical chart reviews. The TMP was examined three or more weeks after surgery. The treatment was repeated up to 4 times until complete TMP closure was achieved.

RESULTS

After mechanical disruption, the perforation size was Grade I, ≤1/3 of entire TM area in 22 ears (9.4 %), Grade II, 1/3-2/3 of entire TM in 77 ears (32.9 %) and Grade III, ≥2/3 of entire TM area in 135 ears (57.7 %). The overall TMP closure rates were 97.0 % (227/234). Complete TMP closure was achieved in 68.8 % (161/234), 22.6 % (53/234), 4.7 % (11/234) and 0.9 % (2/234) of ears after 1, 2, 3 and 4 treatments, respectively. In 7 of 234 ears (3.0 %), the TMPs were not closed completely after 4 treatments. There was no correlation between TMP size after mechanical disruption and number of treatments required to achieve complete closure (Fisher's exact test p = 0.70). The mean air-conduction hearing threshold at low frequency improved from 57.3 ± 16.7 dB before treatment to 37.3 ± 16.0 dB (p < 0.0001) after closure of TMPs. For middle and high frequencies, the improvement was 49.0 ± 19.3 dB to 36.9 ± 17.9 dB (p < 0.0001) and 57.7 ± 22.9 dB to 49.2 ± 23.3 dB (p < 0.0001), respectively. The mean air-bone gaps also improved significantly, and were within 10 dB at 250 Hz, 500 Hz and 1 kHz, and 11 dB at 2 kHz. One or more complications occurred in 32 patients (32/216; 14.8 %). The most common complication was formation of an epithelial pearl (16 ears; 6.8 %), followed by severe TM retraction (9 ears; 3.8 %) and otitis media with effusion (6 ears; 2.6 %). There were no serious complications that caused deterioration of the patient's general condition.

CONCLUSION

Our results showed that RT-TMP had high success rates for TMP closure and good hearing improvement and produced no severe complications that could affect general health status. This novel therapy is simple, safe and minimally invasive, and could help improve the quality of life in patients with TMP.

Feasibility of a Video Otoscope for Diagnosis of Otologic Pathology in the Pediatric Emergency Department

OBJECTIVES

Performing pediatric otoscopy can be difficult secondary to patient compliance, which potentiates misdiagnosis and inaccurate treatment of acute otitis media. This study used a convenience sample to assess the feasibility of using a video otoscope for the examination of tympanic membranes in children presenting to a pediatric emergency department.

METHODS

We obtained otoscopic videos using the JEDMED Horus + HD Video Otoscope. Participants were randomized to video or standard otoscopy, and a physician completed their bilateral ear examinations. In the video group, physicians reviewed otoscope videos with the patient's caregiver. The caregiver and physician completed separate surveys using a 5-point Likert Scale regarding perceptions of the otoscopic examination. A second physician reviewed each otoscopic video.

RESULTS

We enrolled 213 participants in 2 groups (standard otoscopy, n = 94; video otoscopy, n = 119). We used Wilcoxon rank sum, Fisher exact test, and descriptive statistics to compare results across groups. For physicians, there were no statistically significant differences between groups with ease of device use, quality of otoscopic view, or diagnosis. There was moderate agreement between physician video otoscopic view satisfaction and slight agreement between physician video otologic diagnosis. Estimates of length of time to complete the ear examinations were longer more often for the video otoscope compared with standard for both caregivers (OR, 2.00; 95% confidence interval, 1.10-3.70; P = 0.02) and physicians (OR, 3.08; 95% confidence interval, 1.67-5.78; P < 0.01). There were no statistically significant differences between video and standard otoscopy with regard to caregiver perception of comfort, cooperation, satisfaction, or diagnosis understanding.

CONCLUSIONS

Caregivers perceive that video otoscopy and standard otoscopy are comparable in comfort, cooperation, examination satisfaction, and diagnosis understanding. Physicians made a wider range of more subtle diagnoses with the video otoscope. However, examination length of time may limit the JEDMED Horus + HD Video Otoscope's feasibility in a busy pediatric emergency department.

Recurrent Cholesteatoma: Why it occurs?

A cholesteatoma is an expansion of keratinizing squamous epithelium that enters the middle ear cleft from the outer layer of the tympanic membrane or ear canal. Choleatomas are always treated surgically. Recurrence of the illness presents another challenge for the patient and the surgeon, though. There have been reports of recurrence rates as high as 30% in adults and as high as 70% in children. Here, we describe a case of persistent recurrent otorrhea following revision surgery, along with acquired recurrent cholesteatoma following canal wall down surgery. A 38-year -male with underlying Diabetes Mellitus and Hypertension presented with left scanty and foul-smelling ear discharge for 2 years and left reduced hearing. He was diagnosed with left chronic active otitis media with cholesteatoma for which he underwent left modified radical mastoidectomy, meatoplasty and tympanoplasty in 2017. Five months post operatively, he presented with left otorrhea. However, he defaulted followed up and presented in April 2018 for similar complaints. Otoscopy examination revealed left tympanic membrane perforation at poster superior quadrant of pars tensa and bluish discoloration behind pars flacida. He was diagnosed as recurrent left cholesteatoma and subsequently he underwent left mastoid exploration under general anesthesia in June 2018. Postsurgery, he developed recurrent ear discharge which was treated with topical antibiotics and ear toileting. We report a case of recurrent Cholesteatoma despite canal wall down procedure requiring a second redo procedure and with persistent recurrent otorrhea after the redo procedure.However, this case demonstrates the need for regular follow ups even after a canal wall down procedure for detecting recurrence of disease. Moreover, this case denotes some of the patient factors and surgeon factors involved in disease recurrence. Furthermore, importance of opting for an imaging study in case of high suspicion of the disease.

Does the Location of a Small Tympanic Membrane Perforation Affect the Degree of Hearing Loss in Adult Patients with Inactive Mucosal Chronic Suppurative Otitis Media?

BACKGROUND

Tympanic membrane perforation due to inactive mucosal chronic suppurative otitis media is a common problem in otolaryngology, with consequent conductive hearing loss. Still, there is controversy about the relationship between the location of the tympanic membrane perforation and the degree of hearing impairment.

AIM OF THE STUDY

To assess the correlation between the location of a small tympanic membrane perforation and the degree of conductive hearing loss in adult patients with inactive mucosal chronic suppurative otitis media.

PATIENTS AND METHODS

A prospective cross-sectional study enrolled 74 adult patients with small tympanic membrane perforations (perforation involves less than one quadrant of the tympanic membrane) and conductive hearing loss (airbone gap ≥ 20 dB HL) due to inactive mucosal chronic suppurative otitis media for at least 3 months. The locations of the tympanic membrane perforations were classified as anterosuperior, anteroinferior, posterosuperior, and poster inferior perforations. Audiometric analysis and a CT scan of the temporal bone were done for all patients. The means of the air and bone conduction pure tone hearing threshold averages at frequencies 500, 1000, 2000, and 4000 Hz were calculated, and consequently, the air-bone gaps were calculated and presented as means. The ANOVA test was used to compare the means of the air-bone gaps, and the Scheffe test was used to determine if there were statistically significant differences regarding the degree of conductive hearing loss in relation to different locations of the tympanic membrane perforation.

RESULTS

The ages of the patients ranged from 20 to 43 years (mean = 31.9 ± 6.5 years), of whom 43 (58%) were females and 31 (42%) were males. The means of the air-bone gaps were 32.29 ± 5.41 dB HL, 31.34 ± 4.12 dB HL, 29.87 ± 3.48 dB HL, and 29.30 ± 4.60 dB HL in the posteroinferior, posterosuperior, anteroinferior, and anterosuperior perforations, respectively. Although the air-bone gap's mean was greater in the posteroinferior perforation, statistical analysis showed that it was insignificant (P-value=0.168).

CONCLUSION

In adult patients with inactive chronic suppurative otitis media, the anteroinferior quadrant is the most common location of the tympanic membrane perforation, and there was an insignificant correlation between the location of a small tympanic membrane perforation and the degree of conductive hearing loss.

In vivo biodistribution and ototoxicity assessment of cationic liposomal-ceftriaxone via noninvasive trans-tympanic delivery in chinchilla models: Implications for otitis media therapy

OBJECTIVES

We report the in vivo biodistribution and ototoxicity of cationic liposomal-ceftriaxone (CFX) delivered via ear drop formulation in adult chinchilla.

METHODS

CFX was encapsulated in liposomes with size of ∼100 nm and surface charge of +20 mV. 100 μl liposomes or free drug was applied twice daily in both external ear canals of adult chinchillas for either 3 or 10 days. Study groups included free ceftriaxone (CFX, Day 3: n = 4, Day 10: n = 8), liposomal ceftriaxone (CFX-Lipo, Day 3: n = 4, Day 10: n = 8), and a systemic control group (Day 3: n = 4, Day 10: n = 4). Ceftriaxone delivery to the middle ear and systemic circulation was quantified by HPLC assays. Liposome transport was visualized via confocal microscopy. Auditory brainstem response (ABR) tests and cochlear histology were used to assess ototoxicity.

RESULTS

Liposomal ceftriaxone (CFX-Lipo) displayed a ∼658-fold increase in drug delivery efficiency in the middle ear relative to the free CFX (8.548 ± 0.4638% vs. 0.013 ± 0.0009%, %Injected dose, Mean ± SEM). CFX measured in blood serum (48.2 ± 7.78 ng/ml) following CFX-Lipo treatment in ear was 41-fold lower compared to systemic free-CFX treatment (1990.7 ± 617.34 ng/ml). ABR tests and histological analysis indicated no ototoxicity due to the treatment.

CONCLUSION

Cationic liposomal encapsulation results in potent drug delivery across the tympanic membrane to the middle ear with minimal systemic exposure and no ototoxicity.

Endoscopic classification system of pars tensa retractions

BACKGROUND

Previous classification systems of pars tensa retractions have not consistently incorporated ossicular erosion or the presence of cholesteatoma.

OBJECTIVE

This study aimed to illustrate our classification of pars tensa retractions, which is more precise than previous systems, with aided use of the endoscope.

METHODS

A retrospective study was carried out on 200 ears of 170 patients whose pars tensa retractions had been documented at a tertiary otological referral centre.

RESULTS

A classification system was developed. Pars tensa retractions were divided into the following subcategories: grade 0, grade 1, grade 2a, grade 2b, grade 3a, grade 3b, grade 3c, grade 4a, grade 4b, grade 4c, grade 5a, grade 5b and grade 5c.

CONCLUSION

This classification system was able to accommodate all pars tensa retractions. The distribution of grades of pars tensa retractions was based on ossicular status and the presence or absence of cholesteatoma. It is therefore a more applicable, and functionally based system than previous alternatives.

Radiologic evaluation and clinical assessment of facial sinus in adults and children - computed tomography study

OBJECTIVE

The facial sinus is a recess of the lateral retrotympanum located between the chorda tympani (ChT) and facial nerve (FN). Chronic otitis media with cholesteatoma often spreads from the pars flaccida to the facial sinus (FS). In stapedotomy, if an unfavorable ChT type is encountered, there is a need for removal of bone between the ChT and FN. The aim of the study was to assess FSs in adults and children according to Alicandri-Ciufelli classification, to measure FS width and depth in computed tomography scans, evaluate the correlation between measurements and different types of facial sinuses, and provide a clinical context of these findings.

METHODS

Cone Beam Computed Tomography (CBCT) of 130 adults and High Resolution Computed Tomography of 140 children were reviewed. The type of facial sinus was assessed according to Alicardi-Ciufelli's classification in different age groups. Width of entrance to facial sinus (FSW) and depth of FS (FSD) were evaluated among age groups.

RESULTS

Type A of FS is dominant in both adult and children populations included in the study. The average depth of FS was 2.31±1.43 mm and 2.01±0.90 in children and adults respectively. The width of FS was 3.99±0.69 and 3.39±0.98 in children and adults respectively. The depth of FS (FSD) presented significant deviations (ANOVA, p<0.05) among all three types and age groups. In 116/540 (21.5%) cases the value of FSD was below 1 mm.

CONCLUSION

The qualitative classification of facial sinuses into types A, B and C, introduced by Alicandri-Ciufelli and al. is justified by statistically significant differences of depth between individual types of tympanic sinuses. Type A sinuses may be extremely shallow (<1 mm - As) or normal (>1 mm - An). Preoperative assessment of CT scans of the temporal bones gives crucial information about type and size of facial sinus. It may increase the safety of surgeries in this area and play a role in choosing an optimal approach and surgical tools.

Impact of the ear canal motion on the impedance boundary conditions in models of the occlusion effect

The occlusion effect (OE) denotes the increased low-frequency perception of bone-conducted sounds when the ear canal (EC) is occluded. Circuit and finite element (FE) models are commonly used to investigate the OE and improve its prediction, often applying acoustic impedances at the EC entrance and tympanic membrane (TM). This study investigates the sound generation caused by the structural motion of the EC. In addition to the EC wall vibration, it accounts for the motions of the EC entrance and TM, resulting from nondeforming motion of the surrounding structures. A model extension including these motions with the impedances is proposed. Related mechanisms are illustrated based on a circuit model. Implications are discussed by using an EC motion extracted from a FE model of a human head. The results demonstrate that the motions of the EC entrance and TM, addressed by the proposed extension, affects the TM sound pressure and may lead to a reduction of the OE at lower frequencies compared to solely considering the EC wall vibration. Accordingly, this phenomenon potentially reconciles differences between experimental data and OE simulations at frequencies below about 250 Hz, highlighting the importance to discern between multiple contributing mechanisms to the TM sound pressure.

Diagnostic accuracy of the video otoscope in tympanic membrane perforation

OBJECTIVE

The video otoscope has already proven to be useful for the diagnosis of several pathologies, so the objective of this study was to evaluate the diagnostic accuracy of the video otoscope in cases of tympanic membrane perforation.

METHODS

This is a diagnostic accuracy study performed at the hearing health division of a tertiary-level referral hospital. Patients older than 8 years of age who had any symptom that could be related to perforation (otalgia, otorrhea, tinnitus, and/or hypoacusis) were invited to participate in the study. Participants were evaluated by three different diagnostic methods (otomicroscope, conventional otoscope, and video otoscope) performed by three different evaluators in a blind fashion. The microscope was considered the reference standard.

RESULTS

176 patients were evaluated, totaling 352 tympanic membranes. Twenty-seven tympanic membrane perforations were diagnosed by the microscope, a prevalence of 7.7%. The video otoscope showed a sensitivity of 85.2% (95% CI 81.5%‒88.9%), specificity of 98.1% (95% CI 96.7%‒99.5%) and accuracy of 97.1% (95% CI 95.4 %-98.8 %). The conventional otoscope showed a sensitivity of 96.3% (95% CI 94.3-98.3), specificity of 98.8% (95% CI 97.7-99.9) and accuracy of 98.6% (95% CI 97.4-99.8). The Kappa value between the microscope and the video otoscope was 0.8 and between the microscope and the conventional otoscope was 0.9. Regarding the participants' perception, 53.4% (p< 0.001) considered the video otoscope as the best method for understanding the tympanic membrane condition presented by them.

CONCLUSIONS

The video otoscope showed relevant sensitivity and specificity for clinical practice in the diagnosis of tympanic membrane perforation. Moreover, this is an equipment that can facilitate the patient's understanding of the otologic pathology presented by him/her. In this regard, this method may be important for better patient compliance, requiring further studies to evaluate this hypothesis.

LEVEL OF EVIDENCE

Is this diagnostic or monitoring test accurate? (Diagnosis)-Level 2 (Individual cross-sectional studies with consistently applied reference standard and blinding).

Fabrication and optimization of multilayered composite scaffold made of sulfated alginate-based nanofiber/decellularized Wharton's jelly ECM for tympanic membrane tissue engineering

In this study, we fabricated a novel multilayer polyvinyl alcohol (PVA)/alginate sulfate (ALG-S) nanofiber/decellularized Wharton's Jelly ECM (d-ECM) composite for tympanic membrane perforations (TMPs) tissue engineering (TE). Initially, electrospun PVA/ALG-S scaffolds with different blend ratios were fabricated. The influence of ALG-S ratio on surface morphology, mechanical, physical and biological properties of the nanofibers was studied. Secondly, 3-layer composites were developed as a combination of PVA/ALG-S nanofibers and d-ECM to take synergic advantages of electrospun mats and d-ECM. As part of the evaluation of the effects of d-ECM incorporation, the composite's mechanical properties, in vitro degradation, swelling ratio, and biological activities were assessed. The MTT assay showed that PVA/ALG-S nanofibers with 50:50 ratio provided a more desirable environment to support cell growth. A composite containing 25 mg/cm2 d-ECM was determined as the optimal composite through MTT assay, and this composite was used for animal studies inducing TMP regeneration. According to the in vivo studies, the optimal composite not only stimulated the healing of TMPs but also shortened the healing period. These results suggest that a multilayer nanofiber/hydrogel composite could be a potential platform for regenerating TMPs.

Individual similarities and differences in eye-movement-related eardrum oscillations (EMREOs)

We recently discovered a unique type of otoacoustic emission (OAE) time-locked to the onset (and offset) of saccadic eye movements and occurring in the absence of external sound (Gruters et al., 2018). How and why these eye-movement-related eardrum oscillations (EMREOs) are generated is unknown, with a role in visual-auditory integration being the likeliest candidate. Clues to both the drivers of EMREOs and their purpose can be gleaned by examining responses in normal hearing human subjects. Do EMREOs occur in all individuals with normal hearing? If so, what components of the response occur most consistently? Understanding which attributes of EMREOs are similar across participants and which show more variability will provide the groundwork for future comparisons with individuals with hearing abnormalities affecting the ear's various motor components. Here we report that in subjects with normal hearing thresholds and normal middle ear function, all ears show (a) measurable EMREOs (mean: 58.7 dB SPL; range 45-67 dB SPL for large contralateral saccades), (b) a phase reversal for contra- versus ipsilaterally-directed saccades, (c) a large peak in the signal occurring soon after saccade onset, (d) an additional large peak time-locked to saccade offset and (e) evidence that saccade duration is encoded in the signal. We interpret the attributes of EMREOs that are most consistent across subjects as the ones that are most likely to play an essential role in their function. The individual differences likely reflect normal variation in individuals' auditory system anatomy and physiology, much like traditional measures of auditory function such as auditory-evoked OAEs, tympanometry and auditory-evoked potentials. Future work will compare subjects with different types of auditory dysfunction to population data from normal hearing subjects. Overall, these findings provide important context for the widespread observations of visual- and eye-movement related signals found in cortical and subcortical auditory areas of the brain.

Secondary perichondrium patch to enhance cartilage graft during endoscopic cartilage myringoplasty

OBJECTIVES

The aim of this study was to explore the method of adding a secondary perichondrium patch to enhance the primary cartilage-perichondrium patch during endoscopic myringoplasty and to evaluate the effectiveness of this method in terms of healing rate and post-operative hearing of patients with poor prognostic factors (eustachian tube dysfunction, large perforations, subtotal perforations, and anterior marginal perforations).

DESIGN

This retrospective study analyzed a total of 80 patients (36 females and 44 males, median age of 40.55 years) who had received a secondary perichondrium patch during endoscopic cartilage myringoplasty. Patients were followed up for 6 months. Healing rates, complications, preoperative and postoperative pure-tone average (PTA) and air-bone gap (ABG) were analyzed.

RESULTS

At 6-month follow-up, the healing rate of tympanic membrane was 97.5% (78/80). The mean pure-tone average (PTA) improved from 43.18 ± 14.57 dB HL pre-operatively to 27.08 ± 9.36 dB HL 6 months after the operation (P = 0.002). Similarly, the mean ABG improved from 19.05 ± 5.72 dB HL pre-operatively to 9.36 ± 3.75 dB HL (P = 0.0019) at 6 months after the operation. Major complications were not observed during follow-up.

CONCLUSIONS

The use of a secondary perichondrium patch during endoscopic cartilage myringoplasty for large, subtotal and marginal tympanic membrane perforations achieved a high healing rate and a statistically significant hearing gain with low incidence of complications.

Effect of eardrum perforation and chronic otitis media on the results of infrared tympanic thermometer in adults: A systematic review and meta-analysis

BACKGROUND

This study was conducted to determine whether tympanic membrane perforation or chronic otitis media affects the results of an infrared tympanic membrane thermometer in adults.

METHODS

A literature search was performed using PubMed, Embase, Cochrane Library, Web of Science, and Google Scholar.

RESULTS

Four nonrandomized studies were included in the analysis. The temperatures of the bilateral eardrums (one eardrum with normal condition [control group] and the other eardrum with perforation or chronic otitis media [experimental group]) were measured for the same subject in the studies. The mean and standard deviation of the bilateral tympanic membrane temperatures were used to calculate the mean difference (MD) with a corresponding 95% confidence interval (CI). The fixed-effect model was utilized based on the results of the heterogeneity measurement using the Chi2 test and I2 statistic. The results of a meta-analysis in the normal eardrum (control group) and perforated eardrum, chronic suppurative otitis media with tympanic membrane perforation, or chronic otitis media with cholesteatoma (experimental group) were 343 subjects (MD = 0.05; 95% CI = -0.00 to 0.11; P = .06). A meta-analysis of the normal eardrum (control group) and perforated eardrum or chronic suppurative otitis media with tympanic membrane perforation except for cholesteatoma (experimental group) found 296 subjects (MD = 0.05; 95% CI = -0.01 to 0.11; P = .10).

CONCLUSION

When the temperatures of the bilateral eardrums were measured using an infrared tympanic membrane thermometer, no difference was observed between the eardrum with perforation or chronic otitis media and the normal eardrum.

Detection of Spatially Localized Sounds Is Robust to Saccades and Concurrent Eye Movement-Related Eardrum Oscillations (EMREOs)

Hearing is an active process, and recent studies show that even the ear is affected by cognitive states or motor actions. One example are movements of the eardrum induced by saccadic eye movements, known as "eye movement-related eardrum oscillations" (EMREOs). While these are systematically shaped by the direction and size of saccades, the consequences of saccadic eye movements and their resulting EMREOs for hearing remain unclear. We here studied their implications for the detection of near-threshold clicks in human participants. Across three experiments, sound detection was not affected by their time of presentation relative to saccade onset, by saccade amplitude or direction. While the EMREOs were shaped by the direction and amplitude of the saccadic movement, inducing covert shifts in spatial attention did not affect the EMREO, suggesting that this signature of active sensing is restricted to overt changes in visual focus. Importantly, in our experiments, fluctuations in the EMREO amplitude were not related to detection performance, at least when monaural cues are sufficient. Hence, while eye movements may shape the transduction of acoustic information, the behavioral implications remain to be understood.SIGNIFICANCE STATEMENT Previous studies suggest that oculomotor behavior may influence how we perceive spatially localized sounds. Recent work has introduced a new perspective on this question by showing that eye movements can directly modulate the eardrum. Yet, it remains unclear whether this signature of active hearing accounts for behavioral effects. We here show that overt but not covert changes in visual attention modulate the eardrum, but these modulations do not interfere with the detection of sounds. Our results provide a starting point to obtain a deeper understanding about the interplay of oculomotor behavior and the active ear.

A Rare Cause of Red Tympanic Membrane: Jugular Bulb Diverticulum

SIGNIFICANCE STATEMENT

Pulsatile tinnitus with erythematous tympanic membrane mass suggests vascular pathologies such as dural arteriovenous fistula, glomus tympanicum, or aberrant carotid artery. Jugular bulb aneurysmatic diverticulum is rare but should be suspected in a case with the presence of aneurysm in other organs. An imaging study is mandatory to confirm the diagnosis. Patient must avoid digging ear as it can cause profuse bleeding. Treatment option can be open surgery or endovascular treatment.

Solitary fibrous tumor of the tympanic membrane a case report and systematic review

PURPOSE

Otological solitary fibrous tumors (SFT) are exceedingly rare. There has been no report of SFT localized to the tympanic membrane. To report on a rare case of solitary fibrous tumor of the tympanic membrane and provide systematic review of the literature pertaining the demographics and pathophysiology of otological SFTs.

MATERIALS AND METHODS

This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. A search of PubMed, Google Scholar, and Cochrane Library databases was conducted to identify English-language articles on solitary fibrous tumor of the ear, with emphasis on the tympanic membrane, published through 2022. A combination of Boolean operators and the following keywords were included in the search strategy: "solitary fibrous tumor", "tympanic membrane", and "ear".

RESULTS

We found 12 previous reports of solitary fibrous tumors of the ears, none of which were in the tympanic membrane. All cases underwent surgical resection, with or without perioperative embolization, or radiation. There was no evidence of distant diseases in any cases.

CONCLUSIONS

In the context of a tympanic membrane mass with associated pain and hearing loss, our findings suggest that solitary fibrous tumor should be included in the differential diagnosis.

Effect of Auricular Position on Body Temperature Measurement with Tympanic Thermometers: A Quasi Experimental Study

BACKGROUND

With the COVID-19 pandemic, body temperature measurement has begun to be widely used in the diagnosis of the coronavirus disease. When measuring body temperature, it is important to obtain the core temperature measurement. This study compared the results of body temperature obtained with the tympanic membrane thermometer-which is one of the methods that best reflect the body temperature-with or without positioning the auricle.

AIMS

The aim of this study was to investigate the effect of auricle position on body temperature measurements made with tympanic membrane thermometer in adult patients.

MATERIALS AND METHODS

A quasi-experimental design that employed a pre-test and a post-test was used in this study. A total of 143 patients who fit the inclusion criteria of the study were included in the sample. For analysis of the data, frequencies, percentages, means and standard deviations were calculated, and the significance of the difference between paired values was tested in order to investigate the effects of auricle position on measurement values. Statistical Package for the Social Sciences (SPSS) 22.0 was used in analyzing the data obtained in this study.

RESULTS

The difference between the values of measurement taken in these two separate positions was found to be 0.31 0C, and the Bland-Altman plot showed that the differences were distributed systematically around the value 0.31.

CONCLUSIONS

It was found in the comparison of two positions that there was a significant difference between the tympanic thermometer measurements made by positioning the auricle and those without positioning.

Pregnant Patients with Sudden Sensorineural Hearing Loss: Treatments and Efficacy

BACKGROUND

The aim of this study was to study the safety and effectiveness of oral and tympanic hormone injection in the treatment of sudden sensorineural hearing loss during pregnancy.

METHODS

Data were collected via prospective method. A total of 102 pregnant women with sensorineural hearing loss as experimental group and another 102 patients of sensorineural hearing loss without pregnancy as control group were simultaneously included in the study. Pure tone audiometry test was examined at pre- and posttreatment in 1 week, 2 weeks, and 12 weeks. The experimental group received oral and tympanic hormones, while the control group was treated with the Clinical Practice Guideline: Sudden Hearing Loss (2019) of USA. Recovery rate and hearing gain were assessed by the Clinical Practice Guidelines.

RESULTS

After treatment, the effects of the experimental group and the control group were compared at the 1st, 2nd, and 12th week after treatment. It was found that at the 12th week after treatment, the curative effect of the experimental group was significantly different from that of the control group, and the difference was statistically significant.

CONCLUSION

The pregnant women with sensorineural hearing loss were more serious than nonpregnant women, and the treatment efficacies were worse than control group. For pregnancy patients with sudden deafness, oral steroids and tympanic cavity injection is an effective, safe first-line treatment options.

Prospective comparative analysis of zero-heat-flux thermometer (SpotOn®) compared with tympanic thermometer and bladder thermometer in extremely aged patients undergoing lower extremity orthopedic surgery

Thermoregulation is important for maintaining homeostasis in the body. It can be easily broken under anesthesia. An appropriate method for measuring core body temperature is needed, especially for elderly patients, because the efficiency of thermoregulation gradually decreases with age. Zero-heat-flux (ZHF) thermometry (SpotOn) is an alternative, noninvasive method for continuous temperature monitoring at the skin surface. The aim of this study was to examine the accuracy and feasibility of using the SpotOn sensor in lower extremity orthopedic surgery in elderly patients aged over 80 years by comparing a SpotOn sensor with 2 other reliable minimally invasive methods: a tympanic membrane thermometer and a bladder thermometer. This study enrolled 45 patients aged over 80 years who were scheduled to undergo lower extremity surgery. Body temperature was measured using a SpotOn sensor, a tympanic membrane thermometer and a bladder thermometer. Agreements between the SpotOn sensor and the other 2 methods were assessed using Bland and Altman plots for repeated measures adjusted for unequal numbers of measurements per patient. Compared with bladder temperature, bias and limits of agreement for SpotOn temperature were 0.07°C ± 0.58°C. Compared with tympanic membrane temperature, bias and limits of agreement for SpotOn temperature were -0.28°C ± 0.61°C. The 3M SpotOn sensor using the ZHF method for patients aged over 80 years undergoing lower extremity surgery showed feasible measurement value and sensitivity.

Glycerospanlastics: State-of-the-art two-in-one nano-vesicles for boosting ear drug delivery in otitis media treatment

The purpose of this research was to design innovative nanovesicles for ototopical conveyance of triamcinolone acetonide (TA) for otitis media (OM) treatment via incorporating glycerol into nanospanlastics to be termed "Glycerospanlastics". The glycerospanlastics were formulated employing ethanol injection procedure, and central composite design (CCD) was harnessed for optimization of the vesicles. Various attributes of the nanovesicles, viz. particle size distribution, surface charge, TA entrapment efficiency, morphology as well as ex-vivo permeation across the tympanic membrane (TM) were characterized. In vivo implementation of the optimized glycerospanlastics loaded with TA was appraised in OM-induced rats via histopathological and biochemical measurements of the tumor necrosis factor-α (TNF-α) and Interleukin-1β (IL-1β) levels in ear homogenates. The safety and tolerability of optimized TA glycerospanlastics was also investigated in non-OM induced animals. The results demonstrated that the optimized TA-glycerospanlastics were in a nanometer range (around 200 nm) with negative charges, high TA entrapment (>85%), good storage properties and better TM permeation relative to TA suspension. More importantly, TA-glycerospanlastics performed better than marketed drug suspension in OM treatment as manifested by restoration of histopathological alterations in TM and lowered values of IL-1β and TNF-α. Glycerospanlastics could be promising safe ototopical nanoplatforms for OM treatment and other middle ear disorders.

[Bullous myringitis demystified]

Bullous myringitis - also called hemorrhagic myringitis or influenza otitis - is a vague entity, whose etiology and treatment are sources of controversy. In this review article, we demystify bullous myringitis in an illustrated way to recognize and treat it appropriately. Bullous myringitis seems to be a rare and peculiar manifestation of acute otitis media, which can be excessively painful and induce sensorineural hearing loss. Its management may be a medical emergency requiring the opening of hemorrhagic bullae and systemic corticotherapy. The responsible germs are the same as those found in acute otitis media (S. pneumoniæ, H. influenzæ, M. catarrhalis), and its treatment is identical, adapted to each clinical situation.

The External Auditory Canal: Examination and Evaluation

The external auditory canal is a highly specialized skin appendage whose primary purpose is to provide a pathway for the transmission of sound to the tympanic membrane and beyond. It is also a frequent source of symptoms for our patients. Sources of pain, hearing loss, tinnitus, itching, and other sensations can be inferred from an appropriate history. This should be followed by a thorough cleaning of the ear, so that a thorough examination can be performed.

Prestrain in the eardrum investigated using laser-ablation perforation: A proof of principle study on the New Zealand white rabbit

While the presence of residual stress (also called prestress) in the tympanic membrane (TM) was hypothesized more than 150 years ago by von Helmholtz (1869), little experimental data exists to date. In this paper, a novel approach to study residual stress is presented. Using a pulsed laser, the New Zealand white rabbit TM is perforated at seven predefined locations. The subsequent retraction of the membrane around the holes is computed using digital image correlation (DIC). The amount of retraction is the so-called prestrain, which is caused by the release of prestress due to the perforation. By measuring the prestrain using DIC, we show that residual stress is clearly present over the entire rabbit TM surface. In total, fourteen TMs have been measured in this work. An automated approach allows tracking the holes' deformation during the measurement process and enables a more robust analysis than was previously possible. We find similar strains (around 5%) as reported in previous work, in which slits were created manually using flattened surgical needles. However, the new approach greatly reduces measurement time, which minimizes dehydration artifacts. To investigate the effect of perforation location on the TM, the spatial decrease of the prestrain (α) around the perforation was quantified. Perforations inferior to the umbo showed the least negative α values, i.e., the most gradual decrease around the hole, and were the most consistent. Perforations on other locations showed more negative α values, i.e., steeper decrease in strain, but were less consistent across samples. We also investigated the effect of the holes' creation sequence but did not observe a significant change in the results. Overall, the presented method allows for consistent residual stress measurements over the TM surface. The findings contribute to our fundamental knowledge of the mechanics of the rabbit TM and provide a basis for future work on human TMs.

Comparative study of fibroblast growth factor 2 and ofloxacin ear drops for repairing large traumatic perforations: A randomized controlled study

OBJECTIVE

The objective of this study was to compare the healing outcome of fibroblast growth factor 2 (FGF2), ofloxacin ear drops (OFLX) and spontaneous healing for repairing large traumatic tympanic membrane (TM) perforations.

MATERIAL AND METHODS

A total of 75 traumatic large perforations with >1/4 of TM were randomly divided into FGF2 (n = 25), OFLX (n = 25), and spontaneous healing (n = 25) groups. The closure rates, closure times, and hearing gains were compared at 3 months.

RESULTS

At 2 weeks after treatment, the closure rate was 95.8 % in the FGF2 group, 96.0 % in the ofloxacin ear drops group, and 14.3 % in the spontaneous healing group (P < 0.01), respectively. At 3 months after treatment, the closure rate was 100 % in the FGF2 group, 100 % in the OFLX group, and 85.7 % in the spontaneous healing group, no among-group differences were significant (P > 0.05). The mean closure time was 9.69 ± 2.46 days in the FGF2 group, 9.45 ± 2.32 days in the OFLX group, and 30.94 ± 8.95 days in the spontaneous healing group (P < 0.01). The mean ABG was 10.37 ± 2.51 dB for the FGF2 group, 11.01 ± 1.31 dB for the OFLX group, and 10.86 ± 1.94 dB for the spontaneous healing group, no significant difference was found among three groups (P > 0.05).

CONCLUSIONS

This study suggested that both FGF2 and OFLX significantly shortened the mean closure time and improved the closure rate compared with spontaneous healing for repairing large traumatic perforations, while the healing outcome wasn't significantly different among FGF2 and OFLX groups.

Effectiveness of 1 and 2 per cent acetic acid solutions in the 2-week treatment of granular myringitis

OBJECTIVE

Granular myringitis is characterised by de-epithelialisation of the tympanic membrane. Patients present with intermittent otorrhoea, otalgia or itching. With improper or inadequate treatment, granular myringitis could cause ear canal fibrosis and stenosis. There are no standard topical ear drops for granular myringitis. Treatments have inconsistent success rates and variable timelines. This study aimed to compare the effectiveness of treating granular myringitis with 1 and 2 per cent acetic acid solutions for two weeks.

METHOD

This double-blind, randomised, controlled trial enrolled and randomly allocated 47 participants to 2 groups between October 2021 and June 2022.

RESULTS

After two weeks, the groups' treatment success rates did not differ significantly. There was a 10 per cent recurrence rate 8 weeks after treatment completion. All patients tolerated the diluted vinegar.

CONCLUSION

There is no difference in the efficacy of 1 and 2 per cent diluted vinegar in treating granular myringitis for two weeks.

Two-Year Outcomes After Pediatric In-Office Tympanostomy Using Lidocaine/Epinephrine Iontophoresis and an Automated Tube Delivery System

OBJECTIVE

Evaluate 2-year outcomes after lidocaine/epinephrine iontophoresis and tympanostomy using an automated tube delivery system for pediatric tube placement in-office.

STUDY DESIGN

Prospective, single-arm.

SETTING

Eighteen otolaryngology practices.

METHODS

Children age 6 months to 12 years indicated for tympanostomy were enrolled between October 2017 and February 2019. Local anesthesia of the tympanic membrane was achieved via lidocaine/epinephrine iontophoresis and tympanostomy was completed using an automated tube delivery system (the Tula® System). An additional Lead-In cohort of patients underwent tube placement in the operating room (OR) under general anesthesia using only the tube delivery system. Patients were followed for 2 years or until tube extrusion, whichever occurred first. Otoscopy and tympanometry were performed at 3 weeks, and 6, 12, 18, and 24 months. Tube retention, patency, and safety were evaluated.

RESULTS

Tubes were placed in-office for 269 patients (449 ears) and in the OR for 68 patients (131 ears) (mean age, 4.5 years). The median and mean times to tube extrusion for the combined OR and In-Office cohorts were 15.82 (95% confidence interval [CI]: 15.41-19.05) and 16.79 (95% CI: 16.16-17.42) months, respectively. Sequelae included ongoing perforation for 1.9% of ears (11/580) and medial tube displacement for 0.2% (1/580) observed at 18 months. Over a mean follow-up of 14.3 months, 30.3% (176/580) of ears had otorrhea and 14.3% (83/580) had occluded tubes.

CONCLUSION

In-office pediatric tympanostomy using lidocaine/epinephrine iontophoresis and automated tube delivery results in tube retention within the ranges described for similar grommet-type tubes and complication rates consistent with traditional tube placement in the OR.

Predicting wideband real-ear-to-coupler differences in children using wideband acoustic immittance

Individual differences in ear-canal acoustics introduce variability into hearing aid output that can affect speech audibility. Measuring ear-canal acoustics in young children can be challenging, and relying on normative real-ear-to-coupler difference (RECD) transforms can lead to large fitting errors. Acoustic immittance measures characterize the impedance of the ear and are more easily measured than RECD. Using 226 Hz tympanometry to predict the RECD is more accurate than using age-based average RECD values. The current study sought to determine whether wideband acoustic immittance measurements could improve predictions of wideband real-ear-to-coupler difference (wRECD). 150 children ages 2-10 years with intact tympanic membranes underwent wRECD and wideband acoustic immittance measures in each ear. Three models were constructed to predict each child's measured wRECD: the age-based average wRECD, 226 Hz admittance wRECD, and wideband absorbance wRECD. The average age-based wRECD model predicted the child's measured wRECD within 3 dB in 62% of cases, but both the 226 Hz admittance and wideband absorbance wRECD were within 3 dB in 90% of cases. Using individual 226 Hz or wideband absorbance to predict wRECD improved the accuracy and precision of transforms used for pediatric hearing aid fitting.

Prospective Validation of Tubomanometry in Children With Normal Eustachian Tube Function

OBJECTIVES

Tubomanometry (TMM), described initially by Estève, is a relatively new manometric method for testing the eustachian tube function (ETF). This study presents the analysis of the measurement of ETF of healthy children by TMM, which has, to date, not been properly evaluated. The objectives of the study were to establish normative data for TMM and to demonstrate TMM as a reliable and valid method for measuring ETF in children.

DESIGN

The evaluation, after initial power analysis, comprised 35 children from 6 to 15 years of age with an intact tympanic membrane, no severe ET dysfunction, and less than three inflammations of the middle ear in their medical history. TMM was performed twice at three pressure levels for both ears. Statistical assessment of the various parameters of TMM was performed with emphasis on the R value and possible age dependency.

RESULTS

The 90th percentile for the R value was calculated to be 1.12. No clinically relevant age effect regarding the use of TMM as a screening method for children was found. Healthy children showed an opening within normal limits for the so-called R value in 88%; a delayed opening was measured in 6%, and rarely no opening was measured in 2%.

CONCLUSIONS

TMM is a reliable tool for measuring ETF in children. The normal limit for the R value should be set at 1.12. The proposed measuring algorithm and results can be used to calculate sensitivity and specificity in a future study.

Comments on forward pressure and other reflectance-based quantities for delivering stimuli to the ear

The forward pressure has been proposed as an "optimal" reflectance-based quantity for delivering stimuli to the ear during evoked otoacoustic-emission measurements and audiometry. It is motivated by and avoids detrimental stimulus-level errors near standing-wave antiresonance frequencies when levels are adjusted in situ. While enjoying widespread popularity within research, the forward pressure possesses certain undesirable properties, some of which complicate its implementation into commercial otoacoustic-emission instruments conforming to existing international standards. These properties include its inability to approximate the total sound pressure anywhere in the ear canal and its discrepancy from the sound pressure at the tympanic membrane, which depends directly on the reflectance. This paper summarizes and comments on such properties of the forward pressure. Further, based on previous published data, alternative reflectance-based quantities that do not share these properties are investigated. A complex integrated pressure, with magnitude identical to the previously proposed scalar integrated pressure, is suggested as a suitable quantity for avoiding standing-wave errors when delivering stimuli to the ear. This complex integrated pressure approximates the magnitude and phase of the sound pressure at the tympanic membrane and can immediately be implemented into standardized commercial instruments to take advantage of improved stimulus-level accuracy and reproducibility in the clinic.

Long-term exposure to high-concentration dexamethasone in the inner ear via intratympanic administration

The first-line treatment for inner ear disorders is usually oral/systemic steroids. Intratympanic steroid therapy is an alternative option; however, it requires multiple office visits owing to the short residence time of steroids in the inner ear (systemic: 24 h, intratympanic: 2-3 h). Therefore, intratympanic injections of higher steroid concentrations could result in longer drug exposure, providing better treatment outcomes. This study aimed to develop a prototype for high-concentration steroids and examine their safety and feasibility in vivo. Using wild-type Institute for Cancer Research mice, high-concentration steroids (50 mg/mL dexamethasone), typical steroid concentrations (3.3 mg/mL dexamethasone), and sterile saline were administrated into the middle ear cavity via tympanic membrane injection. Auditory brainstem response analysis, vestibular function tests, and morphological analyses were performed to examine the safety and utility of High-conc Dex. One month post-injection, the frequency-averaged auditory brainstem response thresholds of high-dose dexamethasone-treated mice were not significantly different from those of low-dose dexamethasone- and saline-treated mice at all tested frequencies. Furthermore, the total points on vestibular function tests were similar between the three groups. Morphologically, no damage to the inner ear/middle ear mucosa was observed in all groups. Two months post-injection, dexamethasone could still be detected in the high-dose dexamethasone group. Altogether, our data successfully demonstrates the feasibility and safety of high-dose dexamethasone for in vivo use in the middle ear and ensure that the drug localizes to the inner ear. Further research is warranted to develop this new treatment strategy and further characterize its effects in vivo.

Better late than never: initial experience of intra-arterial pulsed-urokinase-injection as a salvage therapy for refractory sudden sensorineural hearing loss

BACKGROUND AND PURPOSE

Cochlear vascular micro-thrombosis has been hypothesized as one of the pathogenic mechanisms for sudden sensorineural hearing loss (SSNHL) refractory to regular management. This study aimed to evaluate the feasibility and safety of intra-arterial pulsed-injection urokinase (IAPU) as a salvage therapy for SSNHL after the failure of conventional therapy.

METHODS

We retrospectively reviewed our patient database to identify refractory SSNHL patients between November 2017 and July 2020. Study outcomes before and after the IAPU therapy were compared between IAPU and conventional therapy groups.

RESULTS

Sixty-seven moderate-profound SSNHL patients (29 in IAUP group, 38 in control group) were included in this study. Compared to the control group, patients in the IAPU group showed more significant improvement in pure tone average (PTA) (34.2 ± 23.5 vs. 10.7 ± 13.1, p < 0.001) and degree of hearing recovery (total: 20.7% vs. 5.3%, partial: 24.1% vs. 10.5%, mild: 27.6% vs. 13.2% and non: 27.6% vs. 71.1%) 2 weeks after admission. In the IAPU group, a significant improvement of PTA (86.6 ± 11.5 vs. 54.6 ± 20.1 dB, p < 0.005) was observed on the first day after IAPU treatment.

CONCLUSION

In carefully selected SSNHL cases with a highly suspected vascular origin, IAPU is a safe and effective therapy when conventional treatments have failed. Despite the encouraging findings of our work, large studies are needed to better investigate the strengths and limitations of this salvage therapy.

Silastic Electrode Positioner Extrusion as a Late Complication of Cochlear Implantation Surgery

It was the aim of this study to report a rare case of electrode positioner extrusion in cochlear-implanted patients as a late complication and introduce safe management. A retrospective case report in a tertiary referral center. Extrusion of Silastic electrode positioner through tympanic membrane occurred 17 years after cochlear implantation surgery. Although electrode positioner cochlear implants are not being used anymore, otologists and surgeons should be aware of their possible related complications and provide a proper management.

Otologic Examination Findings In Afebrile Young Infants Clinically Diagnosed With Acute Otitis Media

There are limited data on examination criteria for diagnosing acute otitis media in young infants. In this 33-site retrospective study of afebrile infants ≤90 days, clinicians typically documented tympanic membrane erythema with ≥1 other otologic abnormalities (64.1%) to diagnose acute otitis media. Notable differences in ear examination findings used for diagnosis existed across age subgroups.

A Novel Non-Invasive Thermometer for Continuous Core Body Temperature: Comparison with Tympanic Temperature in an Acute Stroke Clinical Setting

There is a growing research interest in wireless non-invasive solutions for core temperature estimation and their application in clinical settings. This study aimed to investigate the use of a novel wireless non-invasive heat flux-based thermometer in acute stroke patients admitted to a stroke unit and compare the measurements with the currently used infrared (IR) tympanic temperature readings. The study encompassed 30 acute ischemic stroke patients who underwent continuous measurement (Tcore) with the novel wearable non-invasive CORE device. Paired measurements of Tcore and tympanic temperature (Ttym) by using a standard IR-device were performed 3−5 times/day, yielding a total of 305 measurements. The predicted core temperatures (Tcore) were significantly correlated with Ttym (r = 0.89, p < 0.001). The comparison of the Tcore and Ttym measurements by Bland−Altman analysis showed a good agreement between them, with a low mean difference of 0.11 ± 0.34 °C, and no proportional bias was observed (B = −0.003, p = 0.923). The Tcore measurements correctly predicted the presence or absence of Ttym hyperthermia or fever in 94.1% and 97.4% of cases, respectively. Temperature monitoring with a novel wireless non-invasive heat flux-based thermometer could be a reliable alternative to the Ttym method for assessing core temperature in acute ischemic stroke patients.

Treatment of Meniere's disease by Multi-session Dexamethasone Injections

BACKGROUND

Meniere's Disease (MD) is a complex and multifactorial inner ear problem characterized by episodic vertigo, unilateral sensori-neural hearing loss and tinnitus or fullness in the ear due to Endolymphatic hydrops. There are multiple treatment options available for this disease; from which cortisone therapy can be given in different routes and in different doses.

OBJECTIVES

is to identify the successfulness of treatment of MD by multi-session intra-tympanic dexamethasone injection compared to the single-session method.

METHOD

Interventional prospective study of study 70 cases of definite MD treated by 4 sessions of intra-tympanic injection weekly and compared to a control group of 66 cases of age matched patients with definite MD treated by the traditional single intra-tympanic injection. Patients In the study and the control group were observed for 6 months after the treatment for the development of any vertiginous attacks.

RESULTS

only 3 patients in the study group and 30 patients in the control group failed to respond to treatment and developed vertigo in the period of 6 months after treatment. The difference between the success rate in the two groups was statistically highly significant.

CONCLUSION

multi-session Intra-tympanic dexamethasone injection is superior to the single injection in control of vertigo in patients with definite MD.

Preparation of Antibacterial Gelatin/Genipin Nanofibrous Membrane for Tympanic Membrane Repair

Tympanic membrane perforation (TMP), a common disease, often needs a scaffold as the patch to support surgery. Due to the environment of auditory meatus, the patch can be infected by bacteria that results in failure; therefore, the ideal scaffold may combine biomimetic and antibacterial features. In this work, gelatin was used as the electrospinning framework, genipin as the crosslinking agent, and levofloxacin as an antibacterial in order to prepare the scaffold for TMP. Different contents of levofloxacin have been added to gelatin/genipin. It was found that, with the addition of levofloxacin, the gelatin/genipin membranes exhibit improved hydrophilia and enhanced tensile strength. The antibacterial and cell-cultured experiments showed that the prepared antibacterial membranes had excellent antibacterial properties and good biocompatibility, respectively. In summary, levofloxacin is a good group for the gelatin/genipin scaffold because it improves the physical properties and antibacterial action. Compared with different amounts of levofloxacin, a gelatin/genipin membrane with 1% levofloxacin is more suitable for a TM.

A Non-invasive Method to Assess Tensor Tympani Muscle Contraction in Response to Tactile Stimulation

BACKGROUND

The function of the tensor tympani muscle and its effects, as well as a universal testing procedure, is not yet known. The purpose of this study is to investigate the effect of tactile stimulation on the tensor tympani muscle activity in an attempt to evaluate the functional status of the muscle.

METHODS

In this study, 20 healthy adults aged between 18 and 30 years were included. All participants had their history taken, as well as the evaluation of otoscopy, audiometry, and tympanometry. A modified reflex decay paradigm was used to evaluate the tensor tympani muscle activity, in both humans and a fresh-frozen cadaver. The tactile stimulation was applied by thumb tappings on different forehead areas.

RESULTS

Reflex decay responses were in the form of the absence of a response or either a positive or negative waveform. Tactile stimulation had no impact on reflex decay recordings obtained from the cadaver. There was no significant difference between the waveforms obtained from both ears, at different stimulation frequencies, tactile stimulation areas, or the 3 successive stimuli for 1 individual in 1 ear (P > .05). Changes observed in the reflex decay test upon tactile stimulation seem to be due to tensor tympani muscle activity as supported by the previous findings in the literature.

CONCLUSION

The application of a tactile stimulus on the forehead is a non-invasive test method to assess tensor tympani muscle contraction. Understanding the function of the tensor tympani muscle using a non-invasive method will be helpful during the decision-making process in the practice of otology.

Possible Neoplastic or Proliferative Effects of Intra-Tympanic Platelet-Rich Plasma on the MiddleEarMucosa: A Myth or a Fact to Consider?

BACKGROUND

Platelet-rich plasma is a frequently used plasma-derived material; however, a possible neoplastic or proliferative effect is one of the limiting issues in its use. The aim of our experimental study was to investigate the long-term histological effects of platelet-rich plasma on the middle ear mucosa.

METHODS

The rats were divided into 2 groups randomly (groups 1 and 2). Group 1 represented the control group and 8 rats were included in this group. To the left ear, 0.3 mL of normal saline solution was administered intra-tympanically. No injections were done to the right ears. Group 2 represented the platelet-rich plasma group and 11 rats were included. To the left ears, 0.3 mL of platelet-rich plasma and to the right ears 0.3 mL of normal saline solution was administered intra-tympanically. The intra-tympanic platelet-rich plasma injections were done twice with an interval of 1 week. All animals were sacrificed in the third month. The degree of mucosal thickness, the presence of metaplasia, atypical cells, myofibroblastic infiltration, angiogenesis, and acute or chronic inflammation were evaluated histopathologically.

RESULTS

Histopathological findings in the right and left ears in each group were compared in itself. The degree of inflammation and mucosal thickness were significantly higher in the perforated and saline administered side, in group 1 (P < .001). In group 2, the degree of angiogenesis was significantly higher in the platelet-rich plasma administered side (P < .001). The degree of mucosal thickness was significantly higher in the saline administered side (P < .001).

CONCLUSION

Considering the anti-inflammatory and regenerative features and its safety, intra-tympanic-PRP may, in the future, be an alterna- tive to current intra-tympanic treatment modalities.

gom1 Mutant Mice as a Model of Otitis Media

Otitis media (OM) disease is a common cause of hearing loss that is primarily the result of middle ear infection. At present, our understanding of the mechanisms leading to OM is limited due to the lack of animal models of OM with effusion (OME). Here, we report that the mice with genetic otitis media one (gom1) mutants are prone to OM. gom1 Mice were produced by the N-ethyl-N-nitrosourea (ENU) mutagenesis program as an animal model to study OM. These mice demonstrate many common features of OM, such as middle ear effusion and hearing impairment. We revealed that gom1 mice display various signs of middle ear and inner ear dysfunctions, including elevated thresholds of auditory-evoked brainstem response (ABR) and lack of cochlear microphonic responses. Decreased compliance in tympanometry measurements indicates tympanic membrane and ossicular chain malfunction. We confirmed through histological examinations of middle ear structures that 34/34 (100 %) of the mutant mice suffered from severe OME. While individual ears had different levels of effusion and inflammatory cells in the middle ear cavity, all had thickened middle ear mucosa and submucosa compared to control mice (B6). Moreover, the mutant mice displayed cochlear hair cell loss. These observations also suggested the craniofacial abnormalities in the gom1 mouse model. Together, these results indicate that gom1 mice could be valuable for investigating the genetic contribution to the development of middle ear disease.

Ultrathin Eardrum-Inspired Self-Powered Acoustic Sensor for Vocal Synchronization Recognition with the Assistance of Machine Learning

With the rapid development of human-machine interfaces, artificial acoustic sensors play an important role in the hearing impaired. Here, an ultrathin eardrum-like triboelectric acoustic sensor (ETAS) is presented consisting of silver-coated nanofibers, whose thickness is only 40 µm. The sensitivity and frequency response range of the ETAS are closely related to the geometric parameters. The ETAS endows a high sensitivity of 228.5 mV Pa^-1 at 95 dB, and the ETAS has a broad frequency response ranging from 20 to 5000 Hz, which can be tuned by adjusting the thickness, size, or shape of the sensor. Cooperating with artificial intelligence (AI) algorithms, the ETAS can achieve real-time voice conversion with a high identification accuracy of 92.64%. Under good working property and the AI system, the ETAS simplifies signal processing and reduces the power consumption. This work presents a strategy for self-power auditory systems, which can greatly accelerate the miniaturization of self-powered systems used in wearable electronics, augmented reality, virtual reality, and control hubs for automation.