Composite addition technique: a new method in CT scanning of the posterior fossa.

Since the advent of CT, imaging of the posterior fossa has posed problems. The proximity and density of the temporal bones have created artifacts at the interfaces with brain [1]. Nevertheless, thinner sections through the posterior fossa reduce the partial volume artifacts [2], and the use of a method we call the composite addition technique (CAT) together with higher tube voltage further reduce both partial volume artifacts and beam-hardening effects. Because of the speed at which these scans can be obtained, motion artifacts are reduced as well.