SLP: A Zero-Contact Non-Invasive Method for Pulmonary Function Testing

Structured Light Plethysmography (SLP) is a novel non-invasive method that uses structured light to perform pulmonary function testing that does not require physical contact with a patient. The technique produces an estimate of chest wall volume changes over time. A patient is observed continuously by two cameras and a known pattern of light (i.e. structured light) is projected onto the chest using an off-the-shelf projector. Corner features from the projected light pattern are extracted, tracked and brought into correspondence for both camera views over successive frames. A novel self calibration algorithm recovers the intrinsic and extrinsic camera parameters from these point correspondences. This information is used to reconstruct a surface approximation of the chest wall and several novel ideas for `cleaning up' the reconstruction are used. The resulting volume and derived statistics (e.g. FVC, FEV) agree very well with data taken with a spirometer.

• Type: Journal
• Year: 2010
• Where: BMVC
• Authors: Willem de Boer, Joan Lasenby, Jonathan Cameron, Rich Wareham, Shiraz Ahmad, Charlotte Roach, Ward Hills, Richard Iles
• Keywords: BMVC 2010, Camera, Chest Wall, Chest Wall Volume, Computer Vision