Mild Therapeutic Hypothermia for Tinnitus Management

Tinnitus is the perception of sound in the absence of an external stimulus, commonly described as ringing in the ears. Tinnitus is a highly common condition, with most individuals experiencing it at some point in their lifetime. At least 1 in 10 US adults experience chronic or disabling tinnitus, with a significant negative impact on quality of life, often affecting sleep, concentration, mood, and hearing ability. Tinnitus can be intermittent or constant in nature, and intensity can vary or be exacerbated by stress, noise exposure, or other factors. Currently, there is no widely applicable cure for tinnitus, and management typically includes use of sound therapy, mental health counseling, lifestyle modifications, stress management, and distraction techniques. Tinnitus is associated with changes in auditory function, with hearing loss being the most commonly associated co-morbidity in patients. However, tinnitus can also be observed in patients with normal hearing.

Tinnitus can have a significant deleterious effect on a person's quality of life, and there is currently no cure. State-of-the art treatment options suffer limitations and are often ineffective and complex. Most widely used tinnitus treatments focus on reducing awareness of tinnitus/masking symptoms and the impact on emotional state rather than seeking to address the underlying mechanisms of the sound generation. Treatment modalities include sound therapy using environmental sounds and/or hearing aids, psychological interventions including tinnitus retraining therapy and/or cognitive behavioral therapy, somatosensory stimulation including vagus nerve stimulation and osteopathic manipulation, and distraction exercises including guided breathing and development of new hobbies. Other therapies aim to target the generation of tinnitus, including direct and indirect stimulation of the auditory cortex and/or other brain structures through neuromodulation and pharmacologic intervention. Despite the limited success of many of these treatment modalities, none have been shown to be widely applicable to manage tinnitus severity or provide a treatment for tinnitus.

Modifying temperature of the cochlea is known to influence auditory responses. The study team and others have shown that MTH delivered locally or systemically protects hearing function and cochlear structures against noise-induced hearing loss when compared to normothermic animals. It has also been shown in preclinical studies that MTH is safe. Lamprecht and Morgenstern first observed changes in tinnitus intensity in response to warm and cool caloric irrigations, and they found irrigation with warm (44ºC) water was associated with a perceptual increase in tinnitus, while irrigation with cool (30ºC) water was associated with a perceptual decrease in tinnitus. Recently, the idea of using cool water irrigation to reduce tinnitus was further explored. They found that irrigation with cool water resulted in a decrease in tinnitus perception as well as tinnitus disturbance as measured by the Tinnitus Handicap Inventory (THI).

In this study, investigators aim to show the efficacy of a highly accessible and translatable, non-invasive treatment strategy and device utilizing mild therapeutic hypothermia, or MTH, to reduce tinnitus symptom severity in patients with chronic tinnitus. The study team has designed and manufactured the headband-style device, ReBound, to provide therapeutic hypothermia to the inner ear structures. The aims of the study are:

Aim 1: Ascertain the effects of MTH in chronic tinnitus patients using questionnaires measuring tinnitus severity and intervention-related change. After collection of validated subjective assessments (adapted tinnitus Visual Analog Scale (VAS)) MTH will be delivered bilaterally for 30 minutes in a home setting using custom cold packs placed securely on the temporal bone. Half of the participants will receive a placebo treatment via sham devices. Pre- and post-assessments will be compared between normothermic (sham) and MTH-treated patients at completion of treatment and 24-hours post-treatment. Any adverse events (caloric activation of the vestibular system, skin frostbite) will be closely monitored by an audiologist. Results of Aim 1 will establish MTH as a novel approach for tinnitus symptom management.