A method of determining the presence of a pneumothorax includes obtaining a series of frames of image data relating to a region of interest including a pleural interface of a lung. The image data includes at least a first frame and a second frame. The method further includes identifying, via processing circuitry, the pleural interface in at least the first frame and the second frame, determining, based on computing optical flow between the first and second frames, a pleural sliding classification of the image data at the pleural interface, and determining whether a pneumothorax is present in the pleural interface based on the pleural sliding classification.