Statistical analysis of shape of auricular concha for mass customization of OTC hearing aids / Análisis estadístico de la forma de la concha auricular para la personalización masiva de audífonos de venta libre

SUMMARY: A detailed data of shape of auricular concha is currently not available. Therefore, this study constructed a framework to statistically analyze the shape of the auricular concha based on a database of 3D scanned images. The 3D models of the auricular concha from 308 study participants are converted into compatible NURBS surfaces generated through 795 data points to perform a requisite statistical analysis. Subsequently, the shape of the auricular concha of the participants is grouped into 29 clusters with a modified hierarchical clustering algorithm. Finally, a wear trial and simulation test are carried out to validate the wear comfort of a designed OTC hearing aids based on the average shape of each cluster. The experimental results show that the average shape obtained as per the cluster is capable of representing the common geometric properties of their corresponding members, and could thus be used as a reference in designing mass-customized OTC hearing aid. The method in this study is superior to conventional methods that rely on sparse results for shape analysis because it takes into account the intricate geometric shape of the auricular concha. The quantitative description of conchal morphometry will be beneficial for plastic surgeons, and for the ergonomic design of ear-related products.

RESUMEN: Actualmente no se dispone de datos específicos de la forma de la concha auricular. Por lo tanto, este estudio construyó un marco para analizar estadísticamente la forma de ella a partir de una base de datos de imágenes escaneadas en 3D. Los modelos 3D de la concha auricular de 308 participantes del estudio se convirtieron en superficies NURBS compatibles generadas a través de 795 puntos de datos para realizar un análisis estadístico requerido. Posteriormente, la forma de la concha auricular de los participantes se agrupó en 29 grupos con un algoritmo de agrupamiento jerárquico modificado. Finalmente, se llevó a cabo una prueba de uso y una prueba de simulación para validar la comodidad de uso de unos audífonos OTC diseñados en función de la forma promedio de cada grupo. Los resultados experimentales mostraron que la forma promedio obtenida de la concha auricular, según el grupo, es capaz de representar las propiedades geométricas comunes de sus miembros correspondientes y, por lo tanto, podría usarse como referencia en el diseño de audífonos OTC personalizados en masa. El método de este estudio es superior a los métodos convencionales que se basan en resultados escasos para el análisis de forma, porque tiene en consideración la intrincada forma geométrica de la concha auricular. La descripción cuantitativa de la morfometría de la concha auricular será beneficiosa para los cirujanos plásticos y para el diseño ergonómico de productos relacionados con el oído.

Outcomes of Direct-to-Consumer Hearing Devices for People with Hearing Loss: A Review

As the population of those with mild to moderate hearing loss increases the need remains for amplification solutions. There is a trend to offer alternative amplification options beyond traditional hearing aids. Due to reduced medical risk associated with the most common types of hearing loss (i.e., presbycusis and noise induced), many individuals with such audiological configurations may have success with direct-to-consumer hearing devices (DCHD). The current paper presents a literature review of studies focused on the outcomes of DCHDs for people with hearing loss. Search of electronic databases were used to identify relevant articles for review. Studies on outcomes of DCHDs mainly focused on older adults and reported consistently positive results in clinical and self-reported outcome measures. Improvements in auditory ability, communicative function, social engagement, quality of life, and reduction of self-reported hearing disability were observed. The nature of the direct-to-consumer method makes it challenging to design studies that will accurately represent outcomes for patients due to the extensive dissimilarities in patient journey and device selection options. Accordingly, a majority of the studies conducted on this topic are of low quality of evidence and only provide short-term (i.e., less than one year) outcomes. In addition, results may have been influenced by researcher and/or clinician involvement in choosing the devices and by provision of additional support (i.e., incorporation of a communication partner and communication strategies training). Overall, the literature suggests positive outcomes and self-reported benefit of DCHDs in older adults with hearing loss. However, additional research is needed in this area to verify outcomes.