Ultrasound Measurement of Pleural Line Sliding as a Surrogate Indicator of Lung Volume Change: A Comparative Study With Ventilator Volume Data

For lung ultrasound analysis, we selected ultrasound recordings of the right lower lung apex at the costophrenic angle along the right mid-axillary line. Using the open-source image processing tool ImageJ 1.4, the pleural line corresponding to the right lower lung apex was enhanced and its terminal coordinates extracted. During respiration, the right lower lung apex moves with the breathing cycle, and the pleural line exhibits corresponding motion. The terminal coordinates of the pleural line also shift during respiration, and a plot of this displacement against time is generated to create the pleural line sliding displacement curve.