2014 Volume 32 Issue 2 Pages 132-142
To realize the accurate irradiation targeted to a small volume, confirmation of the target position is very important. A kilo-voltage cone-beam computed tomography (kV-CBCT) system mounted on a linear accelerator can improve the accuracy of irradiation by imaging the target just before the irradiation. However, the kV-CBCT system requires a long data acquisition time, therefore motion of a target causes the degradation of CT images. In this study, we proposed a method to reconstruct target motions in two directions from the projection images, and evaluated the feasibility of the method using the simulation and phantom studies with a dynamic phantom. In this method, we detected the target position in the two directions with the projection image using the template matching method. And a sonograms were constructed from projection data with the particular, and the images for each positions were reconstructed by the filtered backprojection method. The results showed that the blurring of the target caused by the motion was reduced, and we could obtained the reconstructed images incorporating the target motion.
