Breath motion estimation based on image tracking

The organ motion due to respiration is an intra periodic motion. An accurate model of breath motion is difficult since breath motion varies from the different person and even different stage of the same person. So, a statistical model for the breath motion analysis has been used widely to analyze superior-inferior breath motion only, having some difficulties to meet the clinical requirements of real-time and 3D analysis. This paper presented a new technique for breath motion estimation based on the statistics and image tracking. A snake method was used first to track the position of the target, such as the diaphragm in the image set obtained from X-ray imaging machine, and therefore the position-time curve of diaphragm motion could be found. The final breath motion model was constructed as a probability distribution function through calculate the position probability in the duration of image set. The experimental results proved that the model could reflect the real-time breath motion better than the traditional method did and be used to build 3D breath motion model.