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Respiratory and Real-time Dynamics in Exercise-Induced Paradoxical Vocal Fold Motion

Respiratory and Real-time Dynamics in Exercise-Induced Paradoxical Vocal Fold Motion

Status
Recruiting
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07420530
Acronym
EILO
Enrollment
130
Registered
2026-02-19
Start date
2026-08-12
Completion date
2032-01-20
Last updated
2026-08-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Exercise-Induced Vocal Cord Dysfunction, Paradoxical Vocal Fold Motion, Vocal Cord Dysfunction

Brief summary

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.

Detailed description

Main Study At the first study visit, participants will sign informed consent, complete study questionnaires, have their height, weight, and body composition measured, and perform resting pulmonary function tests. Participants will then warm up on the treadmill for 10 minutes. An endoscope will be placed in one nostril until the vocal folds are visible, and subjects will be fitted with a chest strap heart rate monitor, an oro-nasal face mask, and the mechanoacoustic device. This sensor is placed on the neck with a velcro band. Participants will then undergo a graded exercise test during which a carbon-dioxide enriched gas mixture will be administered. The amount of the gas mixture will be titrated based on measures of the participant's breathing and lung function. This visit will be video recorded. At the second study visit, participants will be asked to again wear the mechanoacoustic device while free running for 10 minutes in a large room or on a track. This visit will be video-recorded. At the third study visit, participants will be asked to undergo an MRI scan, during which they will perform a variety of breathing exercises including rest breathing, rapid breathing, pursed lip breathing, sniff, and open mouth breathing. Research personnel will instruct participants in the various breathing techniques prior to the scan. Device Only Substudy Participants will be evaluated using the mechanoacoustic device only at a single visit. Participants will wear the neck device during four sequential conditions: seated rest indoors (15 minutes); standing outdoors (15 minutes); walking outdoors (15 minutes); running outdoors (15 minutes). This visit will be video-recorded.

Interventions

DRUGCarbon Dioxide

Breathing Hypercapnic Gas (10% CO2 (carbon dioxide) and 21%O2 (oxygen), balance N210% (nitrogen))

DEVICEMechano-acoustic device

A 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.

Sponsors

Indiana University
Lead SponsorOTHER
Purdue University
CollaboratorOTHER
National Jewish Health
CollaboratorOTHER
National Institute on Deafness and Other Communication Disorders (NIDCD)
CollaboratorNIH

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 26 Years
Healthy volunteers
Yes

Inclusion criteria

for Exercise-Induced Laryngeal Obstruction (EILO): * 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 * Score of 7 or higher on the Dyspnea Index, which is a validated instrument to capture participant self-report of upper airway dyspnea symptoms. * Classified as low risk, based on the modified Physical Activity Readiness Questionnaire (PAR-Q) questionnaire, body mass index, and non-smoking status * Negative history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers. * No metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc. Inclusion Criteria for Controls * Physically active \>2.5 hours per week * Age range of 18-26 years * Classified as low risk, based on the modified PAR-Q questionnaire, body mass index, and non-smoking status * Negative history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers. * No metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc.

Exclusion criteria

for EILO: * 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 * Current smoker * Positive history of voice disorders, self-report of cognitive difficulties, asthma or other lung disease, cardiac disease, serious orthopedic injuries, current uncontrolled hypertension, illicit drug use, seizure/epilepsy, claustrophobia, use of beta blockers. * Presence of metallic, mechanical or magnetic implants such as cardiac devices, cochlear, or other non-removable ear implants, any prosthesis, stents, deep brain stimulator, etc. * Do not report the following: Greater difficulty breathing inside compared to out and difficulty breathing which is exacerbated at peak exercise and stops 1-5 minutes after exercise

Design outcomes

Primary

MeasureTime frameDescription
Device measurements from real time runningBaseline and PeriproceduralMuscle activation of cricothyroid/sternohyoid muscle measured via customized surface electromyography amplifier
Treadmill testingBaseline and PerioproceduralBreathing frequency (breaths per minute)
MRI Upper Airway SizeBaselineLength (mm), width (mm), and cross-sectional area (mm2) of oropharynx, supraglottis, glottis, immediate subglottis.
Upper Airway AerodynamicsBaseline and Periproceduralpressure (Pa) across oropharynx, supraglottis, and subglottis

Secondary

MeasureTime frameDescription
Self-rating of dyspneaBaselineDyspnea self-rating of breathing intensity and breathing unpleasantness rating on Visual Analog Scale of 0 to 100mm

Countries

United States

Contacts

CONTACTRita R Patel
patelrir@iu.edu812-855-3886
PRINCIPAL_INVESTIGATORRita Patel

Indiana University

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Aug 15, 2026