Audiovisual biofeedback improves diaphragm motion reproducibility in MRI

Area of Science:

• Medical Imaging
• Radiotherapy
• Respiratory Motion Management

Background:

• Breathing variations cause imaging artifacts in lung radiotherapy, impacting tumor targeting.
• Previous studies focused on external signals, leaving internal anatomy motion effects of audiovisual (AV) biofeedback understudied.

Purpose of the Study:

• To test if AV biofeedback improves diaphragm motion reproducibility of internal anatomy using MRI.
• To quantify the impact of AV biofeedback on diaphragm motion consistency.

Main Methods:

• 15 healthy subjects underwent two MRI sessions, one with free breathing and one with AV biofeedback.
• Diaphragm motion was measured using serial thoracic 2D MRI, with AV biofeedback guided by abdominal marker movement.
• Cycle-to-cycle variability in diaphragm displacement, respiratory period, and baseline drift were compared between conditions.

Main Results:

• AV biofeedback reduced diaphragm displacement variability by 38% (p<0.0001).
• Respiratory period variability decreased by 82% (p<0.0001) with AV biofeedback.
• Baseline drift was reduced by 44% (p=0.012), consistent with external marker motion reproducibility.

Conclusions:

• This is the first study to demonstrate AV biofeedback's effectiveness in improving internal anatomy motion reproducibility via MRI.
• AV biofeedback combined with MRI significantly enhances diaphragm motion consistency.
• This technology holds potential for clinically beneficial motion management in MRI and radiotherapy.