A novel video-based method using projected light to measure trunk volumes during respiration

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Physiology

Background:

• Accurate measurement of trunk volume changes during respiration is crucial for understanding respiratory mechanics.
• Existing methods may be invasive or lack the precision required for detailed physiological analysis.

Purpose of the Study:

• To develop and validate an innovative, non-invasive, video-based method for measuring trunk volume during respiration.
• To assess the accuracy and applicability of the proposed method in dynamic respiratory scenarios.

Main Methods:

• Projecting a grid of light markers onto the trunk surface and capturing images with stereo cameras.
• Utilizing surface reconstruction techniques (Power Crust) to create a 3D model from marker coordinates.
• Calculating trunk volume over time using the divergence theorem.

Main Results:

• The method automatically tracked over 2000 points per image, providing detailed trunk surface representation.
• Achieved a relative accuracy of better than 3% in volume measurements.
• Identified signals coherent with respiratory cycles during vital capacity maneuvers.

Conclusions:

• The proposed light projection and surface reconstruction method is accurate and non-invasive.
• It offers a valuable tool for calculating human trunk volumes during breathing.
• This technique has significant potential for respiratory research and clinical applications.