Earmold Foreign Bodies in the Middle Ear Necessitating Surgical Removal: Why Otology Specialists Should Screen Candidates for Hearing Aids

Hearing Aid Silicone Impression Material Discovered During Exploration of the Middle Ear: 2 Case Reports and Literature Review

It is unusual to see complications with the preparation of ear mold in order to get hearing aids for children who are in need. However, we came across 2 cases who had a foreign body retained in the middle ear after a long period of time from taking silicon mold impression for hearing aid fitting. One patient presented after 2 years, and the other patient presented after 10 years of hearing aid fitting. We are reporting 2 cases with silicon impression material left in the middle ear for a long period of time after taking an impression for hearing aid fitting and found unexpectedly during exploratory tympanotomy. These reported cases are among the few cases reported worldwide without clear known incidence. This necessitates proper examination by otolaryngologists and the audiologists who are responsible for taking the impression to prevent such complications.

A Novel Ear Impression-Taking Method Using Structured Light Imaging and Machine Learning: A Pilot Proof of Concept Study with Patients' Feedback on Prototype

INTRODUCTION

Taking an ear impression is a minimally invasive procedure. A review of existing literature suggests that contactless methods of scanning the ear have not been developed. We proposed to establish a correlation between external ear features with the ear canal and with this proof of concept to develop a prototype and an algorithm for capturing and predicting ear canal information.

METHODS

We developed a novel prototype using structured light imaging to capture external images of the ear. Using a large database of existing ear impression images obtained by traditional methods, correlation analyses were carried out and established. A deep neural network was devised to build a predictive algorithm. Patients undergoing hearing aid evaluation undertook both methods of ear impression-taking. We evaluated their subjective feedback and determined if there was a close enough objective match between the images obtained from the impression techniques.

RESULTS

A prototype was developed and deployed for trial, and most participants were comfortable with this novel method of ear impression-taking. Partial matching of the ear canal could be obtained from the images taken, and the predictive algorithm applied for a few sample images was within good standard of error with proof of concept established.

DISCUSSION

Further studies are warranted to strengthen the predictive capabilities of the algorithm and determine optimal prototype imaging positions so that sufficient ear canal information can be obtained for three-dimensional printing. Ear impression-taking may then have the potential to be automated, with the possibility of same-day three-dimensional printing of the earmold to provide timely access.

Foreign Body Complications in Ears due to Mishandled Hearing Aid Fitting and Proposed Clinical Guidelines to Address the Complications

BACKGROUND

South Korea has one of the world's fastest aging populations and is witnessing increased age-related hearing impairment cases as well as an increase in the number of hearing aid users. The aim of this study was to analyze complications caused by hearing aid mold materials. In addition, we hope to raise awareness of the harm and danger that inexperienced hearing aid providers can cause to patients.

METHODS

We retrospectively reviewed the medical records of 11 patients who were diagnosed with hearing aid mold material as a foreign body in the ear at a tertiary center between 2016 and 2020. The following data were analyzed: symptoms, endoscopic findings, audiometry, temporal bone CT images, treatment methods, and complications after removal. The currently available literature was also reviewed to develop clinical guidelines, to identify the systematic weaknesses in the South Korean hearing aid market, and to identify policies that warrant better quality control.

RESULTS

Among the 11 cases, 9 were restricted to the external auditory canal, all of which were successfully removed under endoscopy with minor complications. Two cases with middle ear involvement resulted in infection and thus required surgical removal with mastoidectomy. The average age of these patients was 76.4, and all patients received their molding procedure at private hearing aid shops without an otolaryngologist's examination.

CONCLUSION

Thorough patient history-taking and otologic examination must be performed to identify patients at higher risk of complications. Such patients should be referred to an otolaryngologist. If a patient exhibits alarming symptoms, early referral is critical since prompt surgery can minimize complications. A CT scan is highly recommended to determine an optimal approach for foreign body removal. Systematic and regulatory changes in hearing aid dispensers, such as requiring apprenticeship, raising the required level of education, and legally mandating referrals, can help reduce these complications.

Surgical Removal of Hearing Aid Earmold Impression Material in the Middle Ear

When fitting hearing aids, patients are required to make an earmold impression material for device fixation. It usually causes no problems, although in rare cases, the earmold passes through the middle ear through tympanic membrane perforations.¹-³ Foreign bodies may cause a delayed inflammatory reaction and deterioration of aeration, especially in the Eustachian tube. Herein, we report a rare case of earmold impression material as a foreign body in the middle ear that required surgical removal.

Increased Risk of Psychopathological Abnormalities in Subjects With Unilateral Hearing Loss: A Cross-Sectional Study

Objectives

Although unilateral hearing loss (UHL) has been proven to be associated with educational and behavioral problems, few studies have investigated psychopathological abnormalities in this population. The aim of this study was to evaluate the psychopathological influence of UHL among Korean 19-year-old males.

Methods

The authors retrospectively compared the objective personality test profiles of 602 subjects with UHL with those of 23,790 peers with normal hearing. All participants in the current study were 19-year-old males who underwent a physical examination and completed the Korean Military Multiphasic Personality Inventory for conscription at the Military Manpower Administration from February 2015 to December 2016.

Results

Significantly higher scores were found on neurosis scales in the UHL group than in the normal-hearing group (50.9± 10.8 vs. 44.9±6.0 for anxiety; 51.0±10.5 vs. 44.9±5.2 for depression; 51.1±10.4 vs. 45.1±6.81 for somatization, all P<0.001). The psychopathy scales were also significantly higher in the UHL group than in the normal-hearing group (49.3±9.4 vs. 46.3±5.7 for schizophrenia; 51.1±11.2 vs. 44.3±5.8 for personality disorders; 51.1±10.5 vs. 45.7±3.7 for paranoia, all P<0.001).

Conclusion

Nineteen-year-old males with UHL tended to have more abnormal results on personality tests than controls with normal hearing, suggesting that UHL may be related with a higher risk of psychopathology.