The overall objectives of the proposed research are to:
1. Evaluate the diagnostic validity of a novel mechano-acoustic signatures of task-characteristic activity during symptomatic and asymptomatic breathing in Exercise-Induced Laryngeal Obstruction (EILO) patients with the use of a novel miniature, soft wearable skin-mounted device, 2. Identify the mechanism/s of paradoxical respiratory control in EILO by quantifying the relationship between pulmonary mechanics, partial pressure of carbon dioxide (PCO2) maintenance, and vocal fold aperture prior to and during symptomatic and asymptomatic exercise ventilation, and 3. Identify unique biophysiological factors contributing to EILO among exercisers with and without EILO. Findings will be highly novel and clinically significant for early identification and management of EILO.
The main study will enroll 60 participants with EILO and 60 without EILO to complete three separate visits:
1. Exercise treadmill study 2. Free running with the device on the neck 3. Undergoing MRI (Magnetic Resonance Imaging) of the vocal tract.
An additional substudy limited to the mechanoacoustic device will enroll 10 additional participants (5 healthy and 5 with EILO). These participants will complete a single study visit during which the mechano-acoustic device will be worn during four sequential conditions.
Physically active >2.5 hours per week
Patients with EILO, as diagnosed by routine clinical examination by physician and/or speech language pathologist
Age range of 18-26 years
Greater difficulty breathing inside compared to out and difficulty breathing which is exacerbated at peak exercise and stops 1-5 minutes after exercise
Individuals older than 26 years and younger than 18 years of age.
Women who are pregnant or could possibly be pregnant.
BMI > 25 kg/m2
A 'yes' answer to any of the 14 questions on the PAR-Q pre-participation questionnaire
Parallel
Carbon Dioxide
DrugBreathing Hypercapnic Gas (10% CO2 (carbon dioxide) and 21%O2 (oxygen), balance N210% (nitrogen))
Mechano-acoustic device
DeviceA custom developed mechanoacoustic sensor will be worn on the neck using a Velcro strap. The device will collect audio recordings of breathing and breath sounds and will collect muscle activity from the neck muscles.
Device measurements from real time running
Muscle activation of cricothyroid/sternohyoid muscle measured via customized surface electromyography amplifier
Device measurements from real time running
Normalized amplitude (100% of maximum voluntary contraction) Burst duration (milliseconds) prior to and during Exercise-Induced Laryngeal Obstruction event of laryngeal closure.
Device measurements from real time running
Exercise-Induced Laryngeal Obstruction signature detected via ultra-low noise micro-electromechanical (MEMS) microphone amplitude (dB) prior to and during EILO. EILO signature detected via accelerometer (g, where g represents the gravitational acceleration of 9.8 m/s2) prior to and during EILO
Treadmill testing
Breathing frequency (breaths per minute)
Self-rating of dyspnea
Dyspnea self-rating of breathing intensity and breathing unpleasantness rating on Visual Analog Scale of 0 to 100mm
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Indiana University
Lead sponsor
Purdue University
Collaborator
National Jewish Health
Collaborator
National Institute on Deafness and Other Communication Disorders (NIDCD)
Collaborator
