Modern radiotherapy relies on accurate dose delivery to the prescribed target volume. The ICRU has recommended an overall accuracy in tumour dose delivery of ±5%, based on an analysis of dose response data and on an evaluation of errors in dose delivery in a clinical setting. Considering all uncertainties involved in the dose delivery to the patient, the ±5% accuracy recommendation is by no mea...

Introduction: Dose distribution can be affected by diverse parameters, such as beam orientations, and collimator angles. These parameters should respect and maintain the international recommended levels during the realization of the quality assurance protocols of linear accelerators. This study aimed at evaluating the dosimetric effects on treatment quality considering...

BACKGROUND Rectal cancer patients that show a pathological complete response (pCR) after neo-adjuvant chemo-radiotherapy, have better prognosis. To increase pCR rates several studies escalate the tumor irradiation dose. However, due to lacking tumor contrast on online imaging techniques, no direct tumor setup can be performed and large boost margins are needed to ensure tumor coverage. The purp...

PURPOSE Radiotherapy with concurrent chemotherapy has been recommended as standard treatment for locally advanced cervical cancer. To validate the main tumor location before each high-precision helical tomotherapy (HT) fraction, the development of a more reliable marker or indicator is of clinical importance to avoid inadequate coverage of the main tumor. MATERIAL AND METHODS A 61-year-old wo...

Deformable image registration (DIR) is fundamental technique for adaptive radiotherapy and image-guided radiotherapy. However, further improvement of DIR is still needed. We evaluated the accuracy of B-spline transformation-based DIR implemented in elastix. This registration package is largely based on the Insight Segmentation and Registration Toolkit (ITK), and several new functions were imple...

To compare the set-up uncertainties in breast radiation therapy using two different immobilization methods: vacuum cushion (VC) and standard breast board (BB). The data set comprises of 26 breast cases were divided into two groups based on the type of immobilization used for their radiotherapy treatment, either intensity-modulated radiotherapy (IMRT) or volumetric arc modulated radiotherapy (VM...

Objective: The technology of ABC ( Active Breathing Control) was used in breath-holding time in order to improve the accuracy of radiotherapy for lung cancer patients, and the influence of respiratory movement on diaphragm motion was analyzed and evaluated, in addition the feasibility and limitation of ABC was also assessed. Methods: 15 lung cancer patients were selected for the training of ABC...