Non-rigid CT/CBCT to CBCT registration for online external beam radiotherapy guidance.

Non-rigid CT/CBCT to CBCT registration for online external beam radiotherapy guidance.
Phys Med Biol. 2017 Nov 08;:
Authors: Zachiu C, de Senneville BD, Tijssen RHN, Kotte ANTJ, Houweling AC, Kerkmeijer LGW, Lagendijk JJW, Moonen CTW, Ries MG
Abstract
Image-guided external beam radiotherapy (EBRT) allows radiation dose deposition with a high degree of accuracy and precision. Guidance is usually achieved by estimating the displacements, via image registration, between cone beam computed tomography (CBCT) and computed tomography (CT) images acquired at different stages of the therapy. The resulting displacements are then used to reposition the patient such that the location of the tumor at the time of treatment matches its position during planning. Moreover, ongoing research aims to use CBCT-CT image registration for online plan adaptation.
 However, CBCT images are usually acquired using a small number of X-Ray projections and/or low beam intensities. This often leads to the images being subject to low contrast, low signal-to-noise ratio and artifacts, which ends-up hampering the image registration process. Previous studies addressed this by integrating additional image processing steps into the registration procedure. However, these steps are usually designed for particular image acquisition schemes, therefore limiting their use on a case-by-case basis.
 In the current study we address CT to CBCT and CBCT to CBCT regi...

Source: Physics in Medicine and Biology - November 8, 2017 Category: Physics Authors: Zachiu C, de Senneville BD, Tijssen RHN, Kotte ANTJ, Houweling AC, Kerkmeijer LGW, Lagendijk JJW, Moonen CTW, Ries MG Tags: Phys Med Biol Source Type: research