Conductive hearing loss due to Dehiscence of the Superior Semicircular Canal: Study of cochlear mechanisms in an animal model

• Grant number: 23/14586-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2024
• End date: April 30, 2028
• Field of knowledge: Health Sciences - Speech Therapy
• Principal Investigator: Renata Mota Mamede Carvallo
• Grantee: Diego da Silva Ormundo
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Introduction: Superior Semicircular Canal Dehiscence (SSCD) consists of an opening in the otic capsule that alters cochlear hydrodynamics and results in conductive hearing loss without middle ear involvement. Therefore, this study hypothesizes that the non-linear mechanisms of the cochlea may be impaired in conductive hearing loss due to SSCD. It is believed that, despite presenting conductive characteristics, this type of hearing loss functions as a sensorineural alteration. This study objectives to investigate the non-linear mechanisms of the cochlea in conductive hearing loss due to SSCD in animals in vivo. Method: SSCD will be surgically simulated in swine - Sus scrofa species. Conductive hearing loss will be recorded using Auditory Brainstem Response, for air and bone conduction, and middle ear status will be obtained using Acoustic Immittance Measurements. The non-linear mechanisms of the cochlea will be investigated through threshold, area and slope measurements of the Distortion Product Otoacoustic Emission Growth Curves. Expected Results: Altered growth curves are expected, with a high threshold, reduced amplification area and greater slope inclination. Considerations: This study is motivated by the interest in expanding knowledge of the pathophysiology underlying conductive hearing loss due to SSCD, in order to contribute to the medical and audiological community with regard to the diagnosis of people affected by this clinical entity, given that this topic is still controversial and little explored in the field of audiology.