Sensitivity and Reproducibility of 18F-fluorodeoxyglucose Positron Emission Tomography for Assessment of Respiratory Muscle Activity

Not Applicable

Completed

• Conditions: Respiratory Muscle
• Interventions: Diagnostic Test: 18F-FDG Positron emission tomography - MRI; Diagnostic Test: Multiparametric ultrasound imaging; Diagnostic Test: Surface electromyography; Diagnostic Test: Transdiaphragmatic preasure measurmement; Diagnostic Test: Magnetic stimulation of the phrenic nerves; Diagnostic Test: Ventilation against inspiratory loading

• Registration Number: NCT05234099
• Lead Sponsor: Institut de Myologie, France

Brief Summary

The assessment of respiratory muscle function is critical within both clinical and research settings. Tools for the assessment of respiratory muscle function are especially useful in diagnosing, phenotyping, understanding pathophysiology, and assessing treatment responses in patients with respiratory symptoms, including critically hill patients and patients with respiratory and/or neuromuscular diseases. Respiratory muscle function is most commonly assessed using flow (i.e. spirometry) and pressure measurements during spontaneous ventilation, voluntary respiratory efforts, or artificially evoked responses using magnetic or electrical stimulation. Some of these approaches may be limited within patients suffering from neuromuscular diseases. The study hypothesis is the 18F-FDG PET technology, heavily used for clinical oncology purposes (diagnostic, staging, response to treatment, prognosis), could be an interesting alternative to invasive measurement of the respiratory muscle activity. In addition, it may contribute to further validate metrics based on multiparametric ultrasound imaging.

Detailed Description

The assessment of respiratory muscle function is critical within both clinical and research settings. Tools for the assessment of respiratory muscle function are especially useful in diagnosing, phenotyping, understanding pathophysiology, and assessing treatment responses in patients with respiratory symptoms, including critically hill patients and patients with respiratory and/or neuromuscular diseases. Respiratory muscle function is most commonly assessed using flow (i.e. spirometry) and pressure measurements during spontaneous ventilation, voluntary respiratory efforts, or artificially evoked responses using magnetic or electrical stimulation. Some of these approaches may be limited, for instance, when facial muscle weakness occurs and/or when glottis function is compromised, for example in patients with bulbar amyotrophic lateral sclerosis or myopathies. Consequently, widely used respiratory measures can be poor predictors of respiratory muscle alterations and this may contribute to affect clinical decisions such as the time when non-invasive ventilation should be initiated within the disease continuum.

Positron emission tomography (PET) is a nuclear medicine procedure based on the measurement of positron emission from radiolabeled tracer molecules. These radiotracers allow biologic processes to be measured and whole-body images to be obtained which demonstrates sites of radiotracer accumulation. Fluorodeoxyglucose (18F-FDG) is a radiolabeled glucose molecule and is the most common radiotracer used in clinical practice. 18F-FDG PET is most frequently coupled with computed tomography but may also be coupled with magnetic resonance imaging (18F-FDG PET-MRI). 18F-FDG PET is heavily used for clinical oncology purposes (diagnostic, staging, response to treatment, prognosis). 18F-FDG PET also finds applications in other fields for detecting infections and inflammatory processes. 18F-FDG may also be used in muscles that are major user of glucose. 18F-FDG PET offers the opportunity to assess the patterns and work amount of multiple muscles simultaneously, providing a global view of the muscles involved in the realization of a motor task, as previously demonstrated in shoulder muscles.

Ultrasound imaging (US) is attracting a growing interest for the assessment of respiratory muscle function, as it allows bedside and non-invasive assessments. Recently, new US techniques such as shear wave elastography (SWE) have shown promises for the assessment of respiratory muscle work. However, the ability of variables derived from respiratory muscle US to reflect increased muscle work remains unclear. Hence, building evidences supporting non-invasive US biomarkers for respiratory muscle function is necessary.

18F-FDG PET offers a unique opportunity to investigate patterns and work amount of the respiratory muscles. In a resting state, 18F-FDG uptake in the respiratory muscle is known to be small. However, and to the best of our knowledge, 18F-FDG uptake of the respiratory muscles at rest in healthy subjects has never been specifically reported. It is unclear whether 18F-FDG PET may be used to monitor changes in respiratory muscle activity within the disease continuum or in response to an intervention such as the initiation of non-invasive ventilation. The reproducibility of increase 18F-FDG uptake of the respiratory muscles induced remains to be assessed and is a prerequisite to determine its sensitivity to change. Moreover, the relationship between increase 18F-FDG uptake and respiratory muscle work as assessed using other methods (e.g. flow and pressure measurements, surface electromyography (sEMG)) and variables derived from multiparametric US remains to be determined. Since MRI does not use ionizing radiations, and because of very higher soft-tissue contrast capabilities, combining PET to MRI instead of CT is of better relevance for our PET muscular analyses purpose.

Study Timeline

• Study First Submitted: 2022-02-01
• Study First Submitted QC: 2022-02-01
• Study First Posted: 2022-02-10
• Study Start: 2022-05-05
• Primary Completion: 2023-12-22
• Study Completion: 2023-12-22
• Status Verified: 2024-04
• Last Update Submitted: 2024-04-09
• Last Update Posted: 2024-04-10

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 15

Inclusion Criteria

• Age > 18 yo
• Non-smoker
• Signed informed consent
• Affiliate or beneficiary of a social security scheme

Non-Inclusion Criteria:

• Pregnant or breastfeeding women
• Respiratory, cardiovascular, metabolic, neuromuscular pathologies
• Claustrophobia
• Belonephobia
• Latex allergy
• Persons subject to a legal protection measure or unable to express their consent
• Contraindications to MRI (claustrophobia, metal implants)
• Inability to participate in the study
• Inability to comply with protocol requirements

Exclusion Criteria

• Blood sugar> 1.8 g / L (V1, V2, V3)
• Impossibility of inserting the esophageal and / or gastric tubes (V2, V3)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Control subjects	Surface electromyography	Visit 1 (V1) (Duration: 2.5h) * Information, verification of inclusion and exclusion criteria, information note. * Consent form. * Location of the diaphragm and parasternal intercostal muscle using ultrasound. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging). * Injection of 3 MBq/kg of 18F-FDG. * 1h resting period. * 18F-FDG PET-MRI scan. Visit 2 (V2) 3-10 days after V1 (Duration: 3h) * Location of the diaphragm and parasternal intercostal muscle. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging) * Magnetic stimulation of the phrenic nerves * Ventilation against inspiratory loading * Magnetic stimulation of the phrenic nerves * Injection of 3 MBq/kg of 18F-FDG * 1h resting period * 18F-FDG PET-MRI scan Visit 3 (V3) 3-10 days after V2 (Duration: 3h) - Identical to visit 2
Control subjects	Magnetic stimulation of the phrenic nerves	Visit 1 (V1) (Duration: 2.5h) * Information, verification of inclusion and exclusion criteria, information note. * Consent form. * Location of the diaphragm and parasternal intercostal muscle using ultrasound. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging). * Injection of 3 MBq/kg of 18F-FDG. * 1h resting period. * 18F-FDG PET-MRI scan. Visit 2 (V2) 3-10 days after V1 (Duration: 3h) * Location of the diaphragm and parasternal intercostal muscle. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging) * Magnetic stimulation of the phrenic nerves * Ventilation against inspiratory loading * Magnetic stimulation of the phrenic nerves * Injection of 3 MBq/kg of 18F-FDG * 1h resting period * 18F-FDG PET-MRI scan Visit 3 (V3) 3-10 days after V2 (Duration: 3h) - Identical to visit 2
Control subjects	18F-FDG Positron emission tomography - MRI	Visit 1 (V1) (Duration: 2.5h) * Information, verification of inclusion and exclusion criteria, information note. * Consent form. * Location of the diaphragm and parasternal intercostal muscle using ultrasound. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging). * Injection of 3 MBq/kg of 18F-FDG. * 1h resting period. * 18F-FDG PET-MRI scan. Visit 2 (V2) 3-10 days after V1 (Duration: 3h) * Location of the diaphragm and parasternal intercostal muscle. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging) * Magnetic stimulation of the phrenic nerves * Ventilation against inspiratory loading * Magnetic stimulation of the phrenic nerves * Injection of 3 MBq/kg of 18F-FDG * 1h resting period * 18F-FDG PET-MRI scan Visit 3 (V3) 3-10 days after V2 (Duration: 3h) - Identical to visit 2
Control subjects	Transdiaphragmatic preasure measurmement	Visit 1 (V1) (Duration: 2.5h) * Information, verification of inclusion and exclusion criteria, information note. * Consent form. * Location of the diaphragm and parasternal intercostal muscle using ultrasound. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging). * Injection of 3 MBq/kg of 18F-FDG. * 1h resting period. * 18F-FDG PET-MRI scan. Visit 2 (V2) 3-10 days after V1 (Duration: 3h) * Location of the diaphragm and parasternal intercostal muscle. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging) * Magnetic stimulation of the phrenic nerves * Ventilation against inspiratory loading * Magnetic stimulation of the phrenic nerves * Injection of 3 MBq/kg of 18F-FDG * 1h resting period * 18F-FDG PET-MRI scan Visit 3 (V3) 3-10 days after V2 (Duration: 3h) - Identical to visit 2
Control subjects	Multiparametric ultrasound imaging	Visit 1 (V1) (Duration: 2.5h) * Information, verification of inclusion and exclusion criteria, information note. * Consent form. * Location of the diaphragm and parasternal intercostal muscle using ultrasound. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging). * Injection of 3 MBq/kg of 18F-FDG. * 1h resting period. * 18F-FDG PET-MRI scan. Visit 2 (V2) 3-10 days after V1 (Duration: 3h) * Location of the diaphragm and parasternal intercostal muscle. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging) * Magnetic stimulation of the phrenic nerves * Ventilation against inspiratory loading * Magnetic stimulation of the phrenic nerves * Injection of 3 MBq/kg of 18F-FDG * 1h resting period * 18F-FDG PET-MRI scan Visit 3 (V3) 3-10 days after V2 (Duration: 3h) - Identical to visit 2
Control subjects	Ventilation against inspiratory loading	Visit 1 (V1) (Duration: 2.5h) * Information, verification of inclusion and exclusion criteria, information note. * Consent form. * Location of the diaphragm and parasternal intercostal muscle using ultrasound. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging). * Injection of 3 MBq/kg of 18F-FDG. * 1h resting period. * 18F-FDG PET-MRI scan. Visit 2 (V2) 3-10 days after V1 (Duration: 3h) * Location of the diaphragm and parasternal intercostal muscle. * Measurements at rest (mouth pressures, sEMG, ultrasound imaging) * Magnetic stimulation of the phrenic nerves * Ventilation against inspiratory loading * Magnetic stimulation of the phrenic nerves * Injection of 3 MBq/kg of 18F-FDG * 1h resting period * 18F-FDG PET-MRI scan Visit 3 (V3) 3-10 days after V2 (Duration: 3h) - Identical to visit 2

Primary Outcome Measures

Name	Time	Method
Correlation between multiparametric ultrasound and 18F-FDG PET-MRI during respiratory muscle activity measurement	Through study completion, on average 3 weeks	Existence of a significant correlation between the variables derived from the multiparametric ultrasound and the work of the respiratory muscles induced by the ventilatory spot assessed by 18F-FDG PET-MRI

Secondary Outcome Measures

Name	Time	Method
Significant correlation between measurements of respiratory muscle activity assessed by pressure measurements and increased respiratory muscle work induced by the ventilation against inspiratory loading as assessed by 18F-FDG PET-MRI	Through study completion, on average 3 weeks	Existence of a significant correlation between measurements of respiratory muscle activity assessed by pressure measurements (esophageal pressure, gastric pressure, transdiaphragmatic pressure) and increased respiratory muscle work induced by the ventilation against inspiratory loading as assessed by 18F-FDG PET-MRI
Significant correlation between measures of respiratory muscle activity assessed by sEMG and respiratory muscle work induced by the ventilation against inspiratory loading as assessed by 18F-FDG PET-MRI	Through study completion, on average 3 weeks	Existence of a significant correlation between measures of respiratory muscle activity assessed by sEMG and respiratory muscle work induced by the ventilation against inspiratory loading as assessed by 18F-FDG PET-MRI

Trial Locations

Locations (2)

Association Institut de Myologie; 🇫🇷 Paris, France

Service hospitalier Fréderic Joliot; 🇫🇷 Orsay, France