Overestimation of Low-Dose Radiation in Intensity-Modulated Radiotherapy with Sliding-Window Technique

Abstract

The overestimation in regions of optimal intensity 0.0 by the planning system cannot be resolved by the user. Taking the measured dose in the region of desired intensity 1.0 and other technical limitations (like beam hold interrupts or spikes in the cross and longitudinal profiles) into consideration, the application of an LS of 2.5 cm/s and a DR of 500 MU/min is recommended in order to minimize radiation dose applied to organs at risk, which are located in regions of low intensity, like, for example, the spinal cord.

A Planning Comparison of Dynamic IMRT for Different Collimator Leaf Thicknesses with Helical Tomotherapy and RapidArc for Prostate and Head and Neck Tumors

“…Dose to healthy organs not in the proximity of the PTV arises largely from collimator transmission and scatter radiation from the linac, and this dose is proportional to the number of MUs [28]. Such scattered doses might increase the risk of secondary tumors [13].…”

Simple Proposal for Dosimetry with an Elekta iViewGTTM Electronic Portal Imaging Device (EPID) Using Commercial Software Modules

“…Due to the rising complexity and conformity of irradiation techniques, the demand for an accurate verification of the dose delivered to the patient has also increased [9,20,22]. The possibility of using the EPID to acquire dosimetric information has been increasingly extended.…”

Analysis of low dose level volumes in intensity modulated radiotherapy and 3-D conformal radiotherapy

“…The use of multiple fields reduces large dose regions considerably but increases the low dose regions. [5][6][7][8][9][10] After skin, colorectal, lung, breast & prostate cancer, second primary cancers are the sixth most common group of malignancies in oncology. These secondary cancers also arise from radiation therapy given to primary cancer.…”