Introduction: A dosimetric audit is a quality assurance process (QA) that allows the accuracy of dosimetric and geometric precision to accurately control the delivery of doses. They can be used to evaluate the accuracy of radiation delivery at different radiotherapy centers. Differences in prescriptive doses, depending on the severity of the differences, have potential conseque...

Recent vector supercomputers provide vector memory access to "randomly" indexed vectors, whereas early vector supercomputers required contiguously or regularly indexed vectors. This additional capability, known as "hardware gather/scatter," can be used to great effect in general sparse Gaussian elimination. In this note we present some examples that show the impact of this change in hardware on...

introduction radiotherapy with small fields is used widely in newly developed techniques. additionally, dose calculation accuracy of treatment planning systems in small fields plays a crucial role in treatment outcome. in the present study, dose calculation accuracy of two commercial treatment planning systems was evaluated against monte carlo method. materials and methods siemens once or linea...

Patient dose reduction in C-arm computed tomography by volume-of-interest (VOI) imaging is becoming an interesting topic for many clinical applications. One limitation of VOI imaging that remains is the truncation artifact in the reconstructed 3-D volume. This artifact can either be a cupping effect towards the boundaries of the field-of-view (FOV) or an offset in the Hounsfield values of the r...

Introduction Radiotherapy with small fields is used widely in newly developed techniques. Additionally, dose calculation accuracy of treatment planning systems in small fields plays a crucial role in treatment outcome. In the present study, dose calculation accuracy of two commercial treatment planning systems was evaluated against Monte Carlo method. Materials and Methods Siemens Once or linea...

Introduction: Irregular/blocked fields are routinely used in radiotherapy. The doses of these fields are usually calculated by means of equivalent square method that is inherently prone to uncertainty. On the other hand, Clarkson’s sector integration method is a dose calculation method which offers far better accuracy in dose calculation of irregular fields. The Scatter Air Ratio (SAR) of an in...

Abstract A scattering plate consisting of multiple lead strips is an effective tool for scatter correction and dose reduction in cone-beam CT(CBCT). Existing methods take advantage data redundancy by partially blocking cone beam from a single scan to make up perform correction. However, geometric objects with large angles during CBCT scans, existing backprojection-filteration(BPF) algorithms ca...