A Statistical Model of Respiratory Motion and Deformation of the Liver

This paper presents a statistical model of the respiratory motion and deformation of the liver. Individual models were made for seven volunteers using a series of MR images taken throughout the breathing cycle. One image was selected as a template and the others were registered to this using an intensity-based non-rigid registration algorithm. The resulting free-form transformations allowed us to map landmarks defined on the template image into their correct positions throughout the breathing cycle. Principal component analysis of these landmarks was used to produce a statistical model of motion and deformation. Results showing typical motion and deformation for a single volunteer are presented.