Figure 1.
RGPT system at Hokkaido University.
(a) The gantry of the passive scattering PBT system. (b) The gantry of the RGPT system. (c) The footprint for one gantry and one fixed beam system with a linear accelerator and synchrotron, and (d) The actual RGPT system installed.
Figure 2.
Design of a spot-scanning proton beam therapy-dedicated system with X-ray fluoroscopy.
Two orthogonal sets of X-ray fluoroscopic generators and flat panels can be mounted in the gantry.
Figure 3.
CT images and target delineations.
Computed tomography for the patients with hepatocellular carcinoma included in this study. Gross tumor volumes (red), clinical target volumes (green), liver (blue), and planning target volumes for the RGPT (white) for patient A (left) and patient B (right).
Figure 4.
Tumor motions obtained with RTRT system.
Eight patterns of tumor motion derived from actual data of internal fiducial markers near hepatocellular carcinomas in the X-ray RTRT of 8 patients.
Table 1.
x, y, and z components of the amplitude of movement of a fiducial marker near the tumor, and data acquisition time, in 8 patients with hepatocellular carcinomas.
Table 2.
Parameters used in the treatment planning.
Figure 5.
Diagram of the (a) synchrotron operation and (b) beam waiting function.
The operation cycle of the synchrotron varies approximately from 2 to 7
Table 3.
Treatment times for FBPT and RGPT.
Figure 6.
Comparison of dose distribution between FBPT and RGPT.
Images of the dose distributions with FBPT for PTVfb(left), FBPT for PTVrg (center), and RGPT for PTVrg (right) for the CT images of patient B with tumor motion ID of b.
Table 4.
Maximum and minimum doses in CTV scaled by the prescribed dose, and mean liver doses in FBPT and in RGPT, averaged over 6 initial timings of motion data.