Segmentation of the tongue surface in ultrasonic images using modified scale space filtering

For the detection of motility disturbances during swallowing and articulation B-mode sonography is used. In general these images of a median sagittal plane through the tongue and the floor of the mouth are manually contoured by the physician, because it is quite difficult to get subtle information concerning tongue movement and motility from the real-time video images. The digitised images built a spatiotemporal space with a depth of about 70 frames. The authors´ application demonstrates a way to extract the tongue contour automatically. They use a modified scale space filter for edge detection. In this way contour segments of the tongue dorsum and other object parts are extracted. A model of the tongue supports identification of the tongue segments and interpolation of the plane in the spatiotemporal space. A virtual three-dimensional view of these contours of the spatiotemporal space assists the physician to a diagnosis of the movement disturbance