Ansa Cervicalis and Hypoglossal Nerve Stimulation in OSA

NCT ID: NCT05501236

Last Updated: 2025-10-15

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 100 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-11-03
• Study Completion Date: 2026-11-30

Brief Summary

Polysomnography (PSG) and drug-induced sleep endoscopy (DISE) are widely used diagnostic studies for assessing obstructive sleep apnea (OSA) severity and collapse patterns of the upper airway anatomy during sleep. Hypoglossal nerve stimulation (HNS) therapy for obstructive sleep apnea suffers from variable response at the level of the soft palate. The Investigators propose a study examining the physiologic effect of ansa cervicalis stimulation (ACS) alone and in combination with HNS during PSG and DISE.

Detailed Description

Obstructive Sleep Apnea (OSA) is a common disorder characterized by repetitive upper airway collapse during inspiration caused, in part, by a loss of neuromotor tone in specific upper airway muscles, with multiple associated health sequelae impacting millions of Americans. Patient adherence to the reference treatment, positive airway pressure (PAP), remains problematic. Despite the recent promising development of hypoglossal nerve stimulation (HNS) as a surgical therapy, its indications are limited and a proportion of eligible patients do not achieve sufficient response, leaving a critical unmet need for effective therapeutic alternatives to PAP.

This project challenges the long-held concept that the genioglossus muscle is primarily responsible for the maintenance of pharyngeal patency during sleep and proposes a novel therapeutic mechanism. It is built upon strong evidence that caudal pharyngeal traction from the trachea has a marked impact on pharyngeal patency primarily mediated through changes in lung volume. Contraction of the sternothyroid muscle, an infrahyoid cervical strap muscle that inserts onto the thyroid cartilage, also generates caudal pharyngeal traction. Our data suggest that ansa cervicalis stimulation (ACS) of the sternothyroid muscle unfolds and stretches the lateral pharyngeal walls and tensions the distal edge of the soft palate caudally, increasing airway patency.

The major hypothesis of the Investigators is that ACS overcomes specific anatomic and neuromuscular defects of upper airway control that restore pharyngeal patency in patients with OSA. This hypothesis is supported by published and preliminary data demonstrating that: (1) the degree of end-expiratory lung volume decrease in sleep correlates with observed increases in pharyngeal collapsibility, and (2) unilateral ACS increases maximum inspiratory airflow and velopharyngeal cross-sectional area during flow-limited breathing in sedated humans. These findings suggest that (3) tracheal traction, as mediated by end-expiratory lung volume (EELV), is a major contributor to airway patency in sleep. In this project, the Investigators will elucidate specific mechanisms for control of pharyngeal patency with caudal traction during drug-induced sleep endoscopy (DISE) and natural sleep (PSG). The Investigators will address these aims by characterizing (1) the effects of ACS of the sternothyroid muscle(s) on upper airway pressure-area and pressure-flow relationships, and (2) determine how subject anatomic, physiologic, and polysomnographic characteristics modulate these responses.

Conditions

Obstructive Sleep Apnea

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Muscle stimulation

Consented participants who meet eligibility will have a drug induced sleep endoscopy (DISE) and second sleep study and the Grass S88 (or comparable) muscle stimulator.

Group Type: EXPERIMENTAL

Grass S88 Muscle Stimulator

Intervention Type: DEVICE

The Grass S88 nerve and muscle stimulator is a widely-used tool in electromyography and nerve conduction studies. During the DISE and second sleep study, fine-wire electrodes will be placed into the hypoglossal nerve or genioglossus muscle. Two more electrodes are placed transcutaneously, proximate to the bilateral branches of the cervicalis innervating the sternothyroid muscle in the anterior neck.

Interventions

Grass S88 Muscle Stimulator

The Grass S88 nerve and muscle stimulator is a widely-used tool in electromyography and nerve conduction studies. During the DISE and second sleep study, fine-wire electrodes will be placed into the hypoglossal nerve or genioglossus muscle. Two more electrodes are placed transcutaneously, proximate to the bilateral branches of the cervicalis innervating the sternothyroid muscle in the anterior neck.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

1. Consenting adults with BMI≥ 25 and ≤ 40 kg/m2

2. Obstructive sleep apnea with an AHI between 20 and 80 events/hr (with hypopneas defined by 4% oxyhemoglobin desaturations); ≥80% obstructive events.

Exclusion Criteria

1. Chronic use of opiate medications, illicit drug use, or alcohol dependency

2. Other known concomitant sleep disorder (e.g., central sleep apnea, periodic limb movements, narcolepsy)

3. Clinical history or evidence of cardiopulmonary disease (or oxygen use), liver, renal, immunodeficiency, neurodegenerative diseases, or previous adverse reactions to anesthesia.

4. Prior upper airway reconstructive surgery excluding tonsillectomy (e.g., cleft palate repair, uvulopalatopharyngoplasty)

5. Indwelling neurostimulation device (e.g. cardiac pacemaker, spinal, vagal, or hypoglossal nerve stimulator)

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Vanderbilt University Medical Center

OTHER

Sponsor Role: lead

Responsible Party

David Kent

Assistant Professor, Department of Otolaryngology-Head and Neck Surgery

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

David T. Kent, MD

Role: PRINCIPAL_INVESTIGATOR

Vanderbilt University Medical Center

Locations

Vanderbilt University Medical Center

Nashville, Tennessee, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Katie Hartley-Estes, RPSGT

Role: CONTACT

katherine.e.hartley@vumc.org

615-875-9214

Nicole L Jones, MS

Role: CONTACT

nicole.l.jones@vumc.org

615-936-2807

Facility Contacts

Katie Estes-Hartley, RPSGT

Role: primary

katherine.e.hartley@vumc.org

615-875-9214

Nicole L Jones, MS

Role: backup

nicole.l.jones@vumc.org

615-936-2807

Other Identifiers

212305

Identifier Type: -

Identifier Source: org_study_id