Transposition of Dynamic MRI Data From Healthy Subjects to an in Vitro Swallowing Simulator

Summary

Swallowing is a complex process, involving a very fine synchronization of the pharyngo-larynx, with respiration, under the control of the central nervous system and numerous peripheral effectors. Any dysfunction can lead to aspiration a source of morbidity and mortality.

These dysfunctions of the aerodigestive tract affect a considerable number of patients with multiple etiologies: squamous cell carcinoma of the upper aerodigestive tract, peripheral or central neurological dysfunctions, neurosurgical or neurovascular causes, geriatric pathologies and intensive care complications.

Aspiration pneumopathy is the most severe complication, which can lead to death. For decades, only techniques such as tracheotomy or enteral feeding (nasogastric tube/gastrostomy tube), associated or not with speech therapy, have been proposed to counter this problem. These invasive treatments remain symptomatic. These treatments bypass the pharyngolaryngeal dysfunction without resolving it and still significantly alter the patients' quality of life.

In 2012, a first worldwide clinical study (published in the NEJM) based on 6 patients, conducted by the ENT team in Strasbourg, demonstrated an improvement in the quality of life of patients who had undergone total laryngectomy, by proposing the placement of a titanium laryngeal implant equipped with an upper valve. This strategy intended to avoid aspiration of food hile allowing normal breathing. Although this technique did not solve all problems (the persistence of food going the wrong way), this study allowed a conceptual change in the attempt to solve swallowing problems by the introduction of pharyngolaryngeal implants.

The latter remains a challenge, but clinical trials of implants with a functional valve effected after removal of the larynx or on an existing but dysfunctional larynx have demonstrated the indivisibility of the pharynx-larynx couple in the search for permanent solutions.

This physiological process can be studied with imaging. Videofluoroscopy is the reference method allowing a dynamic study of swallowing. However, it does not allow the study of soft tissue movement and exposes the patient to repeated irradiation. Recently, MRI has shown its ability to visualize the entire pharyngolaryngeal structures accurately and dynamically during the swallowing process.

To improve the understanding and resolution of swallowing disorders, a unique robotic platform, consisting of a dynamic silicone skeleton reproducing the complexity of the pharyngolarynx, was initially developed by PROTIP MEDICAL (SWALL-E). This is the object of a French patent, transferred to the HUS University Hospitals of Strasbourg.

The aim this study is to correlate and calibrate this platform with dynamic MRI data in healthy subjects, by studying the movement of the different anatomical structures of the pharyngolarynx during swallowing movements (speed, amplitude and synchronization of the pharyngolarynx movements).

The immediate application of SWALL-E, after calibration and validation, will: i) allow the reproduction of a physiological swallowing mechanism; ii) allow to produce a pathological and personalized simulation of swallowing disorders in vitro; iii) allow the design of implants produced by 3D printing, and to analyze their effectiveness before implantation; iv) to modify in parallel and if necessary the rheology of the food boluses, thus contributing to a significant global improvement for the patient.

Thus, this platform, unique in its conception, aims not only at making a diagnosis of the specific pathology of the patient, but also aims at a personalized management adapted to the patient, inexistent until now.

Indeed, if the diagnostic methods are numerous (nasofibroscopy, swallowing transit, videofluoroscopy, study of swallowing noises by acoustic signals, swallowing cinetigraphy...), the treatments have remained identical for decades (speech therapy), and are not targeted (pharyngeal stimulation), despite the fact that each patient presents a specific pathology that is difficult to reunify under a "universal" treatment.

Conditions

• Imaging Data Collection From Dynamic Swallowing MRI in Healthy Volunteers
• Create Operating Algorithms
• Apply the Imaging Data of MRI to a Swallowing Simulator

Interventions

OTHER

Real-time MRI of swallowing

The examination recording a total of 9 sequences of less than 30 seconds will be performed, in transverse section (passing through the epiglottis), frontal section, in the plane of the posterior pharyngeal wall, and in median sagittal section. Each bolus of 20 ml will be administered in full, in one go, using a syringe. It is kept in the mouth for a few seconds and swallowed on demand. The semi-liquid bolus of 20 ml comes from the mixture of 198 ml of pineapple juice to 10 gr of Nutilis Powder (NUTRICIA), food thickener containing neither gluten, nor lactose. Ingredients: Dextrin-maltose, thickeners (modified starch (corn), tara gum, xanthan gum, guar gum). * 3 sequences with no food * 3 sequences with ingestion of a liquid bolus of 20 ml (pineapple juice) mouth closed * 3 sequences with ingestion of a semi-liquid bolus of 20 ml (pineapple juice + Nutilis Powder) mouth closed

Sponsors & Collaborators

• University Hospital, Strasbourg, France

  lead OTHER

Study Design

Allocation

NA

Purpose

OTHER

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Max Age

60 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2021-10-26

Primary Completion

2022-07-27

Completion

2022-07-27

Countries

• France

Study Locations