Is Laryngeal Ultrasound Useful in the Assessment for ILO? A Protocol for a Two-stage Exploratory Pilot Study

Recruiting

• Conditions: Vocal Cord Dysfunction; Inducible Laryngeal Obstruction; Asthma Brittle; Paradoxical Vocal Fold Motion
• Interventions: Other: Trans-cutaneous Laryngeal ultrasound (TLUS); Other: TLUS and simultaneous laryngoscopy

• Registration Number: NCT05686941
• Lead Sponsor: Lancashire Teaching Hospitals NHS Foundation Trust

Brief Summary

This study is a feasibility study to see if an ultrasound scan of the vocal cords can detect narrowing of the vocal cords as seen in a condition called inducible laryngeal Obstruction (the vocal cords narrow or close on breathing in, which makes it very difficult to breathe).

Detailed Description

This study aims to help understand whether viewing the vocal cords with an ultrasound device is useful to detect the movement of the vocal cords during breathing. This study is useful, as some people who have abnormal movements of the vocal cords on breathing in find it more difficult to breathe in, and often this leads to a big impact on their quality of life. It may also mean they are on medications that they may not need not be on, as abnormal movements of the vocal cords can often be mistaken for asthma, so they may have been placed on asthma medication when they may not need to be.

Usually, the way the abnormal movements of the vocal cords are seen now is via a small camera is placed via the nose into the throat to directly look at the vocal cords. Some people find this uncomfortable and may have to wait for a long time for it to happen. Also, this procedure is expensive, and is done in an endoscopy theatre, which may make it more daunting for some people, and make the wait longer. There are only a few centres that do these assessments with the camera, so people may have to travel some distance to have an assessment.

It is hoped, by doing this study, the investigators can see whether ultrasound can help assess if people have abnormal vocal cord movements when they breathe in. This will be done in 2 stages, one with healthy volunteers, and the second stage in patients who have been referred for assessment of their vocal cords to see if they have abnormal movements when breathing in. The investigators will also ask the volunteers and patients what their experience of having the ultrasound was like, and will ask the patients in the study how the ultrasound scan felt, when compared to the camera test

Study Timeline

• Study Start: 2022-08-24
• Study First Submitted: 2022-12-16
• Study First Submitted QC: 2023-01-13
• Study First Posted: 2023-01-17
• Status Verified: 2024-02
• Last Update Submitted: 2024-02-21
• Last Update Posted: 2024-02-22
• Primary Completion: 2025-06-27
• Study Completion: 2025-06-27

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

Healthy volunteers:

• No definite signs or symptoms of vocal fold paralysis
• No voice change
• No history laryngeal surgeries
• No History of pathology
• No uncontrolled Respiratory disease

Exclusion Criteria

• Participants with a known vocal fold pathology
• Participants with a history of head and neck surgery.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Healthy Volunteers	Trans-cutaneous Laryngeal ultrasound (TLUS)	Employees of the Host organisation in the Respiratory Team who meet the inclusion criteria
Patients with suspected Inducible laryngeal Obstruction (ILO)	Trans-cutaneous Laryngeal ultrasound (TLUS)	Patients referred to a Tertiary referral centre who are suspected of having ILO
Patients with suspected Inducible laryngeal Obstruction (ILO)	TLUS and simultaneous laryngoscopy	Patients referred to a Tertiary referral centre who are suspected of having ILO

Primary Outcome Measures

Name	Time	Method
To assess the sensitivity, specificity and positive predictive value of the use of ultrasound	1 day	To assess the sensitivity, specificity and positive predictive value of the use of ultrasound in the assessment of ILO, using Laryngoscopy as reference standard in the patient population (n=30)
Number of particpants where visualisation of mimicked inspiratory adduction is visible on ultrasound	1 day	Can the vocal cords be seen to adduct under TLUS when healthy volunteers mimic ILO? Binary outcome: yes or no.
Number of vocal cords that are seen with the ultrasound	1 day	Can the vocal cord be seen under TLUS for Healthy Volunteers? Numeric data.
Questionnaire Investigating user perspectives on the acceptability of TLUS	1 day	A qualitative questionnaire investigating the patient and healthy volunteer perspectives on their experiences of undergoing TLUS assessment of the vocal cords. The questionnaire will look at the acceptability of the assessment in terms of comfort, repeatability, and comparison with laryngoscopy (for patients only).

Trial Locations

Locations (1)

Lancashire Teaching Hospitals NHS Trust; 🇬🇧 Preston, Lancashire, United Kingdom