The improved accuracy in tumor identification with FDG-PET has led to its increased utilization in target volume delineation for radiotherapy treatment planning in the treatment of lung cancer. However, PET/CT has constantly been influenced by respiratory motion-related image degradation, which is especially prominent for small lung tumors in the peri-diaphragmatic regions of the thorax. Here, ...

PURPOSE There are no accepted guidelines for target volume definition for online image-guided radiation therapy (IGRT) after radical prostatectomy (RP). This study used cone beam CT (CBCT) imaging to generate information for use in post-RP IGRT. METHODS AND MATERIALS The pelvic anatomy of 10 prostate cancer patients undergoing post-RP radiation therapy (RT) to 68.4 Gy was studied using CBCT i...

Patients with left-sided breast cancer are at risk of cardiac toxicity because of cardiac irradiation during radiotherapy with the conventional 3-dimensional conformal radiotherapy technique. In addition, many patients may receive chemotherapy prior to radiation, which may damage the myocardium and may increase the potential for late cardiac complications. New radiotherapy techniques such as in...

To reduce the radiation dose given to patients, a tube current modulation (TCM) method has been widely used in diagnostic CT systems. However, the TCM method has not yet been applied to a kV-CBCT system on a LINAC machine. The purpose of this study is to investigate if a TCM method would be desirable in a kV-CBCT system for image-guided radiation therapy (IGRT) or not. We have developed an atte...

Background: Application of the image-guided radiotherapy (IGRT) system for gastric cancer involving daily verification of patient positioning on the treatment machine allows minimisation of geometrical errors as a consequence of intra- and inter-fraction motion. The purpose of this study was to define the intrafraction motion in gastric cancer patients during a treatment session based on the IG...

The use of Cone beam CT (CBCT) systems for Image Guided Radiotherapy is rapidly expanding in the developed world. With its use comes concern for the increased risks of additional radiation exposure. Quantification of the imaging dose is necessary in order to report, optimise and justify CBCT exposures. This article reviews the current methods of dose measurement and calculation including dose m...

In computer vision and image analysis, image registration between 2D projections and a 3D image while obtaining high accuracy and real-time computation is challenging. In this paper, we propose a novel method that can speedily detect the object’s 3D rigid motion or deformation from a small set of its 2D projection images. The method consists of two stages: registration and pre-registration lear...

In image-guided radiation therapy (IGRT), volumetric information on patient anatomy at treatment conditions is made available with in-room imaging devices capable of cone-beam CT. Setup error and inter-fraction rigid motion can be corrected online. The planning margin can therefore be reduced significantly. However, to compensate for uncertainties including organ deformation and intra-fraction ...

A feasibility study of a novel PET-based molecular image guided radiation therapy (m-IGRT) system was conducted by comparing PET-based digitally reconstructed planar image (PDRI) registration with radiographic registration. We selected a pair of opposing parallel-plane PET systems for the practical implementation of this system. Planar images along the in-plane and cross-plane directions were r...