Mechanisms of Upper Airway Obstruction

NCT04322097 | Completed Results DMC FDA Device

• 1 other identifier: 833511
• Study Type: interventional
• Target: 133
• Locations: 1 country
• Sites: 1

Brief Summary

The current study is designed to examine underlying mechanisms of action of lingual muscles in the maintenance of airway patency during sleep. The investigators' major hypothesis is that specific tongue muscles are responsible for relieving upper airway obstruction during sleep.

Conditions

Obstructive Sleep Apnea

Keywords

upper airway; pharynx; collapsibility; compliance; drug-induced sleep endoscopy; hypoglossal stimulation

Outcome Measures

Primary Outcomes (3)

• Pharyngeal Critical Pressure (Pcrit)

  Upper airway collapsibility (Pcrit, cmH₂O): Pressure at which the upper airway closes during inspiration, with a higher value indicating greater collapsibility. Pcrit less than zero indicates that the airway remains open. Pcrit greater than or equal to zero indicates that the airway is closed.

  Collected during drug-induced sleep endoscopy (<1 day).

• Pharyngeal Opening Pressure (PhOP)

  Measurement of upper airway collapsibility (cmH2O)

  Collected during drug-induced sleep endoscopy (<1 day).

• Pharyngeal Compliance

  Pressure-area relationships

  Unable to be determined

Other Outcomes (2)

• Tongue Force - Maximum

  Assessed at a single visit

• Tongue Force - Fatigue

  Assessed at a single visit

Study Arms (3)

Study A - Functional Phenotyping during DISE

NO INTERVENTION

Participants with diagnosed OSA undergo Drug-Induced Sleep Endoscopy (DISE) to characterize determinants of upper airway obstruction using CPAP and pharyngeal manometry. Jaw thrust and other positional maneuvers are performed during DISE as part of routine clinical standard of care.

Study B - HGNS Responders

EXPERIMENTAL

Participants with implanted Inspire HGNS devices undergo DISE and overnight polysomnography to assess upper airway responses with and without HGNS stimulation. CPAP titration is performed during DISE. Upper airway MRI and tongue force assessments are also conducted. Response was defined by a ≥ 50% reduction in AHI with stimulation.

Device: Hypoglossal Nerve Stimulation

Study B - HGNS Nonresponders

EXPERIMENTAL

Participants with implanted Inspire HGNS devices undergo DISE and overnight polysomnography to assess upper airway responses with and without HGNS stimulation. CPAP titration is performed during DISE. Upper airway MRI and tongue force assessments are also conducted. Nonresponse was defined by a \< 50% reduction in AHI with stimulation.

Device: Hypoglossal Nerve Stimulation

Interventions

Hypoglossal Nerve Stimulation DEVICE

On/off responses will be assessed both during Drug-Induced Sleep Endoscopy (DISE) and Polysomnography (PSG).

Study B - HGNS Nonresponders; Study B - HGNS Responders

Eligibility Criteria

• Age: 22 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Scheduled to undergo DISE as part of routine clinical standard of care.
• Adults (≥ 22yrs) willing and capable of providing informed consent
• Implanted with the MRI-conditional Inspire hypoglossal nerve stimulator (Model 3028 or later)
• Compliant with Inspire therapy (\> 20 hours/week over 2+ weeks) as a standalone treatment for sleep-disordered breathing
• Inspire remote model 2500 or later.

You may not qualify if:

• MRI contraindications (claustrophobia, ferromagnetic implants/foreign bodies, etc.)
• Inspire Implant Model 3024
• Inspire Remote Model 3032
• Patients who have fallen asleep while during resulting in an accident or "near miss" accident within 1 year prior to device implantation.
• Inability to sleep in the supine position (by self-report)
• History of severe difficulty initiating or maintaining sleep in the laboratory
• Pregnant women

Sponsors & Collaborators

• University of Pennsylvania: lead

Study Sites (1)

Pennsylvania Hospital

Philadelphia, Pennsylvania, 19107, United States

Location

MeSH Terms

Conditions

Sleep Apnea, Obstructive; Patient Compliance

Condition Hierarchy (Ancestors)

Sleep Apnea Syndromes; Apnea; Respiration Disorders; Respiratory Tract Diseases; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Nervous System Diseases; Patient Acceptance of Health Care; Treatment Adherence and Compliance; Health Behavior; Behavior

Limitations and Caveats

Recruitment for Study B was delayed by COVID-19, impacting sample size and timelines. Technical difficulties prevented pressure-area measurements in all participants. Digital morphometrics were uninterpretable; detailed MRI scans provided a more accurate assessment of craniofacial and tongue anatomy. Data are presented as mean (SD) with t-tests (stratified by responder status), as limited sample size restricted adherence to the original statistical plan.

Results Point of Contact

• Title: Raj Dedhia, MD
• Organization: University of Pennsylvania

raj.dedhia@pennmedicine.upenn.edu

2158293720

Study Officials

• Raj C Dedhia, MD

  University of Pennsylvania

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Masking Details: Participants and investigators are aware of intervention status.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor, Director, Division of Sleep Surgery

Study Record Dates

• First Submitted: March 19, 2020
• First Posted: March 26, 2020
• Study Start: June 3, 2020
• Primary Completion: May 10, 2024
• Study Completion: May 10, 2024
• Last Updated: January 21, 2026
• Results First Posted: January 21, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share
• Time Frame: As of July, 2025, all data has been transmitted to NSRR.
• Access Criteria: See criteria at the URL below.

Locations

US (1)