Evaluation of upper airway collapsibility using real-time MRI

Area of Science:

• Medical Imaging
• Cardiorespiratory System
• Sleep Medicine

Background:

• Obstructive sleep apnea (OSA) is a common disorder characterized by upper airway collapse during sleep.
• Accurate assessment of airway collapsibility is crucial for understanding OSA pathophysiology and guiding treatment.
• Current methods for assessing airway collapsibility can be invasive or time-consuming.

Purpose of the Study:

• To develop and validate a real-time magnetic resonance imaging (MRI) method for quantifying upper airway collapsibility.
• To demonstrate the utility of this technique in patients with obstructive sleep apnea (OSA) and healthy volunteers.
• To establish a non-invasive and efficient tool for assessing airway collapsibility.

Main Methods:

• Utilized a 3 Tesla MRI scanner with a radial CAIPIRIHNA sequence and parallel imaging with compressed sensing.
• Calculated airway compliance and projected closing pressure (Pclose) using segmented airway areas and synchronized facemask pressure.
• Acquired data from adolescent OSA patients, adult OSA patients, and healthy volunteers, monitoring physiological parameters in real-time.

Main Results:

• Demonstrated significant differences in airway compliance and Pclose between healthy controls and OSA patients (P < 0.001).
• Found that airway collapsibility is not solely determined by airway narrowing.
• The real-time MRI method successfully quantified airway collapsibility in all study participants.

Conclusions:

• The developed real-time MRI method provides a reliable means to assess upper airway collapsibility in OSA.
• This technique allows for the calculation of compliance and Pclose within a 30-minute awake scan.
• The findings support the use of this MRI method for improved OSA diagnosis and management.