Room: Exhibit Hall
Purpose: The purpose of this study was to assess the accuracy of 6D image registration software using cone beam computed tomography (CBCT) provided by two manufacturers.
Methods: The 6D image registrations were performed with online for planning computed tomography (CT) image and CBCT images. The CBCT import and alignment software (BrainLAB) and the TrueBeam system software (Varian Medical Systems) were employed for 6D image registrations of head and pelvic phantoms. These software can correct patient position along 6D (anterior-posterior, superior-inferior, left-right, yaw, pitch, and roll axes). First, the phantom position was normalized by applying registration results from the planning CT and CBCT images after initial phantom setup on each software. The phantom was then positioned with predefined values yield a 6D shift of each treatment couch. Then, the phantom was scanned with CBCT and registered with the planning CT using the two 6D image registration software. The registration results were used to assess the correction accuracy of translational and rotational setup errors. The root mean squares (RMS) of the residual error between predefined values and registration results as well as the standard deviations (SD) of registration results were calculated.
Results: The RMS with the CBCT import and alignment software with respect to translations and rotations were smaller than 0.25 mm and 0.24 deg. for the head and pelvic phantoms, respectively. The RMS with the TrueBeam system software with respect to translations and rotations were smaller than 0.24 mm and 0.13 deg. for the head and pelvic phantoms, respectively.
Conclusion: Both 6D image registration software showed high accuracy in auto matching for the head and pelvic phantoms.
Image Guidance, Cone-beam CT, Registration