Analysis of digitized lateral fluoroscopy images to quantify the volume displaced by the diaphragm

Methods have previously been been developed for accurately measuring the volume displaced by motion of the diaphragm (ΔVdi) and the contribution of the diaphragm to inspired volume. These methods require accurate measurements of (i) the surface area swept by the diaphragm during inspiration, (ii) the area within this that is occupied by the vertebral column and associated tissues, and (iii) the diameter of the lower rib cage. Existing methods of measurement are labor intensive and slow. We present a more accurate and efficient system for the acquisition, distortion correction, interactive segmentation and functional analysis of fluoroscopic images. This new non-invasive technique will allow earlier and more accurate detection of abnormal diaphragm function and have a direct clinical application.