Machine Learning Models for Predicting Hearing Prognosis in Unilateral Idiopathic Sudden Sensorineural Hearing Loss

Objectives@#. Prognosticating idiopathic sudden sensorineural hearing loss (ISSNHL) is an important challenge. In our study, a dataset was split into training and test sets and cross-validation was implemented on the training set, thereby determining the hyperparameters for machine learning models with high test accuracy and low bias. The effectiveness of the following five machine learning models for predicting the hearing prognosis in patients with ISSNHL after 1 month of treatment was assessed: adaptive boosting, K-nearest neighbor, multilayer perceptron, random forest (RF), and support vector machine (SVM). @*Methods@#. The medical records of 523 patients with ISSNHL admitted to Korea University Ansan Hospital between January 2010 and October 2017 were retrospectively reviewed. In this study, we analyzed data from 227 patients (recovery, 106; no recovery, 121) after excluding those with missing data. To determine risk factors, statistical hypothesis tests (e.g., the two-sample t-test for continuous variables and the chi-square test for categorical variables) were conducted to compare patients who did or did not recover. Variables were selected using an RF model depending on two criteria (mean decreases in the Gini index and accuracy). @*Results@#. The SVM model using selected predictors achieved both the highest accuracy (75.36%) and the highest F-score (0.74) on the test set. The RF model with selected variables demonstrated the second-highest accuracy (73.91%) and F-score (0.74). The RF model with the original variables showed the same accuracy (73.91%) as that of the RF model with selected variables, but a lower F-score (0.73). All the tested models, except RF, demonstrated better performance after variable selection based on RF. @*Conclusion@#. The SVM model with selected predictors was the best-performing of the tested prediction models. The RF model with selected predictors was the second-best model. Therefore, machine learning models can be used to predict hearing recovery in patients with ISSNHL.

Microbiological Results From Middle Ear Effusion in Pediatric Patients Receiving Ventilation Tube Insertion: Multicenter Registry Study on the Effectiveness of Ventilation Tube Insertion in Pediatric Patients With Chronic Otitis Media With Effusion: Part

OBJECTIVES: The aim of this multicenter registry study was to investigate the effectiveness of ventilation tube insertion and the microbiology of otitis media with effusion (OME) in children. This part I study was conducted to evaluate the microbiological profile of children with OME who needed ventilation tube insertion. METHODS: Patients < 15 years old who were diagnosed as having OME and received ventilation tube insertion were prospectively enrolled in 16 tertiary hospitals from June 2014 to December 2016. After excluding patients with missing data, the data of 397 patients were analyzed among a total of 433 enrolled patients. The clinical symptoms, findings of the tympanic membrane, hearing level, and microbiological findings were collected. RESULTS: In 103 patients (25.9%), antibiotics were used within 3 weeks before surgery. Ventilation tube insertion was performed in a total of 710 ears (626 in both ears in 313 patients, 55 in the left ear only, and 29 in the right ear only). Culture of middle ear effusion was done in at least one ear in 221 patients (55.7%), and in a total of 346 ears. Only 46 ears (13.3%) showed positive results in middle ear effusion culture. Haemophilus influenzae (17.3%, followed by coagulase-negative Staphylococcus and Staphylococcus auricularis) was the most common bacteria detected. CONCLUSION: H. influenzae was the most commonly found bacteria in middle ear effusion. Relatively low rates of culture positivity were noted in middle ear effusion of patients with OME in Korea.

The Protective Effect of Egb 761 Against 3-Nitropropionic Acid-Induced Hearing Loss: The Role of Sirtuin 1

OBJECTIVES: Local administration of 3-nitropropionic acid (3-NP) to the inner ear induces sensorineural hearing loss. Several studies have shown the otoprotective effects of ginkgo biloba extract EGb 761. Moreover, EGb 761 has been reported to activate Sirtuin 1 (SIRT1). The present study was designed to investigate whether EGb 761 prevents 3-NP-induced sensorineural hearing loss and determine its effects on the expression of SIRT1. METHODS: Sprague Dawley rats were divided into four experimental groups: control group receiving vehicle of 3-NP, EGb group receiving EGb 761, 3-NP group receiving 3-NP, and EGb+3-NP group receiving EGb 761 and 3-NP. EGb 761 was given orally for 5 days. The 3-NP solution was injected into the tympanum 3 days after the start of EGb 761 administration. The auditory brainstem response was recorded before and after the injection. At 4 weeks after the administration of 3-NP or vehicle of 3-NP, cochleae were harvested, and hematoxylin and eosin staining and immunohistochemistry for SIRT1 antibody were performed. RESULTS: EGb+3-NP group showed significantly lower threshold shifts than 3-NP group. There was a significant preservation of type II fibrocytes and spiral ganglion cells in EGb+3-NP group than in 3-NP group. In EGb+3-NP group, there was a significantly greater number of SIRT1 immunopositive type II fibrocytes and spiral ganglion cells than in 3-NP group. Calculating the percentage of SIRT1 immunoreactive type II fibrocytes and spiral ganglion cells in viable type II fibrocytes and spiral ganglion cells, respectively, EGb+3-NP group showed significantly higher SIRT1 immunoreactive cells than 3-NP group. CONCLUSION: These results suggest that EGb 761 may prevent hearing loss induced by 3-NP in an acute ototoxic animal model, which appears to be related with SIRT1 expression.

Clinical Implications of Septal Deviation in Lateralized Olfaction

OBJECTIVES: Results of butanol threshold tests (BTTs) have shown that birhinal olfaction tends to converge toward monorhinal olfaction of the dominant nostril. However, birhinal olfaction may also be worse than dominant-side monorhinal olfaction. The goal of our study was to investigate the effect of deviated nasal septum on birhinal olfaction in patients with lateralized olfaction and to examine the effect of septoplasty in these patients. METHODS: A retrospective study with planned data collection was conducted in 518 patients who underwent BTTs. Lateralized olfaction was defined as monorhinal BTT scores that differed by >2 between sides. Underestimated birhinal olfaction was defined as a birhinal BTT score >2 lower than the dominant nostril monorhinal BTT score. Patients with lateralized olfaction were divided into 2 groups: group 1, underestimated birhinal olfaction; and group 2, without underestimated birhinal olfaction. RESULTS: Among 518 patients, 112 with lateralized olfaction were enrolled in this study. Group 1 included 23 patients (20.5%) and group 2 included 89 patients (79.5%). The severity of septal deviation (ratio of the distance of narrower side to wider side) did not differ between the 2 groups. Septal deviation to the dominant nostril was more common in group 1 than group 2 (73.9% vs. 37.6%; P=0.002). Five patients with septal deviation to the dominant nostril with underestimated birhinal olfaction underwent septoplasty. Improved lateralized olfaction occurred in all 5 patients postoperatively (P=0.041). CONCLUSION: Septal deviation of the dominant nostril in patients with lateralized olfaction is associated with underestimated birhinal olfaction. Septoplasty may improve olfaction by increasing airflow in the dominant olfactory side.

A Spontaneous Pneumatocele Presenting with External Auditory Canal Obstruction / 대한이비인후과학회지

A pneumatocele is an air-filled cavity in the body. In the head and neck areas, the extensive hyperpneumatization of the temporal and occipital bones is typically associated with pneumatocele formation, which results in the spontaneous collection of gas, usually air, beneath the pericranium or within the skull. We herein report a case of stenosis of the external auditory canal caused by a left mastoid pneumatocele in a 12-year-old boy who was successfully treated with left simple mastoidectomy and canaloplasty.

Development of a More Effective Hearing Screening Questionnaire for Infants and Children during Medical Check-Ups / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To improve hearing screening, we developed a more effective hearing screening questionnaire for infants and children to be utilized during medical check-ups. SUBJECTS AND METHOD: Through literature review and discussions with an advisory council, we selected 10 questions to ask parents at each of the seven screening periods for their infants and children. In total, 223 parents of infants and children with and without hearing impairment (119 normal hearing, 104 hearing impaired) answered questionnaires at seven university hospitals in Korea. The advisory council modified questions with regard to sensitivity, specificity, positive, and negative prediction rate, preventing duplication among screening periods, and to address other questions related to development. RESULTS: For hearing screens, we asked five questions per screening period. Collectively, these questions had 40-100% sensitivity and 45-90% specificity at each of the seven screening periods. CONCLUSION: Although we do not advise that hearing questionnaires replace hearing tests, we developed in this study a more effective questionnaire that we suggest could be utilized during medical check-ups to enhance the hearing screening process.

Subjective and Audiologic Results of Bone Anchored Hearing Aids (BAHA) / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: This study aims to evaluate audiologic results and subjective satisfaction of bone anchored hearing aids (BAHA) patients. SUBJECTS AND METHOD: Preoperative air-conduction and bone-conduction thresholds, postoperative aided thresholds were measured for 14 patients. To evaluate patient satisfaction, two questionnaires derived from single sided deafness (SSD) questionnaire and Bern Benefit in SSD questionnaire were used. RESULTS: The mean age of patients, consisting of 8 males and 6 females, was 40.0+/-5.9 year. Ten patients (71%) received implantations for conductive or mixed hearing loss and 4 (29%) for SSD. The mean follow-up period was 27.8+/-5.6 months. The mean preoperative bone-conduction threshold of conductive or mixed hearing loss group was 21.4 dB and the mean air-conduction threshold was 65.4 dB. The mean bone-conduction threshold of SSD group was 60.0 dB and the mean air-conduction threshold was 105.9 dB. The postoperative aided threshold was significantly improved in conductive or mixed hearing loss group (p=0.005). The patients in the conductive or mixed hearing loss group showed more satisfaction with BAHA than those in the SSD group did, but the degree of satisfaction was not statistically significant (p=0.08 for questionnaire 1, p=0.12 for questionnaire 2). Patients with better preoperative bone-conduction threshold and patients with better preoperative speech discrimination score showed more satisfaction with BAHA in the questionnaire 1 (p=0.045, p=0.036). CONCLUSION: BAHA can be considered effective and beneficial for patients with conductive or mixed hearing loss and SSD. Further studies will be needed to choose the appropriate indications for BAHA, especially in SSD group in Korea.

Role of Endolymphatic Sac Decompression in Intractable Meniere's Disease / 대한평형의학회지

BACKGROUND AND OBJECTIVES: The role of endolymphatic sac decompression (ELSD) for the treatment of intractable Meniere disease (MD) has been debated. However, considering few treatment options for medically intractable MD with serviceable hearing or intractable bilateral MD, ELSD has shown reasonable treatment results without ablating inner ear function. The aims of this study are to review the role of ELSD in the treatment of MD and clinical course and long-term outcome after ELSD. MATERIALS AND METHODS: The ELSD was performed in 7 patients among 603 definite Meniere disease patients between May 2003 and December 2010. Patient's medical history and clinical courses after surgery were obtained by medical record review and telephone interview. RESULTS: Mean duration of follow up until receiving ELSD was 575 days since initial visit. Six patients showed complete control or substantial control of vertigo, but one patient suffered from sustained vertigo attacks even after ELSD, the vertigo was controlled after intratympanic gentamicin injection (ITGI) at 20 months after ELSD. Another patient had recurrence of vertigo after 30 months, which was successfully controlled by ITGI. The preoperatively mean monthly vertigo was 4.8 and it was significantly decreased to 1.5 after postoperatively 1 year, 0 after postoperatively 2 years (p<0.001). Hearing was preserved in 6 patients during the follow-up period. CONCLUSION: Most patients who were uncontrolled vertigo with 3 to 6 months medication showed significantly reduced vertigo and hearing preservation after ELSD. The ELSD seems to be a beneficial treatment option for intractable MD.