Prevention of Hidden Hearing Loss and Synaptopathy Following Noise Overexposure with Targeted Temperature Management
Abstract
The human ear is highly sensitive to noise and blast exposures, which leads to sensorineural hearing loss (SNHL). New research has shown that exposure to everyday noises (such as music concerts or sports events) or intense noise over a short duration (blasts, firearms, machinery, or construction) negatively impact sensory structures and neurons in the human cochlea. The hearing and ringing experienced after such exposure can recover and often is not detected in standard hearing tests. Unfortunately, such noise harms delicate structures and cells in the cochlea that may become permanent in the long term. This is called Hidden Hearing Loss (HHL). HHL and SNHL to this date remain untreatable as no U.S. Food and Drug Administration (FDA)-approved drugs available. The hearing loss is often associated with a decline in the quality of life of the patient. Hearing loss and balance issues resulting from damage to the ear are the most prevalent military service-related disabilities, reduce the preparedness of our military and negatively impact life of our Veterans. Injuries to the auditory system accounted for one-quarter of all injuries among marines during Operation Iraqi Freedom, for example. Repeated injuries caused by noise or by exposure to blasts during military operations can lead to a progressive hearing loss and structural damage that manifests in forms of communication disorders, posttraumatic stress, attention deficits, and difficulties in social environments many years after the last injury and negatively impact military readiness. Furthermore, a U.S. Centers for Disease Control and Prevention report highlights that 24% of adults and 17% of teenagers in the United States alone experience hearing loss from exposure to occupational or recreational loud sound. The significant global health problems presented by noise and blast-related hearing loss require investigations into how the hearing organs are damaged. It is also imperative and our call of duty that we build upon this knowledge of injury mechanisms and design novel therapies for the Service Members. The long-term goal of the present proposal is to develop at-home novel applications of a non-pharmaceutical, noninvasive, local, therapeutic hypothermia to the inner ear organs during the critical time window following noise or blast trauma. The proposed studies will build upon common knowledge that cooling reduces inflammation following any injury. This approach is used currently in clinics and has been shown to be safe and effective for spinal cord injuries, concussions, and traumatic brain injuries. We will extend this application through careful studies in a relevant preclinical model representative of traumas experienced during military operations. We will build devices designed to noninvasively provide local, percutaneous hypothermia to the ear. Hearing and balance functions in treated and untreated animals will be evaluated in the long term. Working with industry partners, we will develop new techniques and devices for preservation of hearing and balance functions in American Service Members and the civilian population from many different injuries that can cause hearing loss.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2024
- Source ID
- HT94252310709
Entities
People
- Suhrud Rajguru
Organizations
- Leonard M. Miller School of Medicine
- United States Army