Developing a dose-volume histogram computation program for brachytherapy

Abstract

A dose-volume histogram (DVH) computation program was developed for brachytherapy treatment planning in an attempt to benefit from the DVH's ability to present graphically information on 3D dose distributions. The program is incorporated into a planning system that utilizes a pair of orthogonal radiographs to localize the radiation sources. DVHs are calculated for the volume of tissue enclosed by an isodose surface (e.g. half the value of the reference isodose). The calculation algorithm is based on a non-uniform random sampling that gives a denser point distribution at the centre of the implants. Our program was tested and proved to be fast enough for clinical use and sufficiently accurate (i.e. computation time of 20 s and less than 2% relative error for one point source, for 100,000 calculation points). The accuracy improves when a larger calculation point number is used, but the computation time also increases proportionally. The DVH is presented in the form of a simple graph or table, or as Anderson's 'natural' DVH graph. The cumulative DVH tables can be used to extract a series of indexes characterizing the homogeneity and the dose levels of the distribution in the treatment volume and the surrounding tissues. If a reference plan is available, the DVH results can be assessed relative to the reference plan's DVH.

Methods, software and datasets to verify DVH calculations against analytical values: Twenty years late(r)

“…This way, analyzing dose and volume differences is actually the examination of dose and volume errors caused by assumptions, limitations, or errors in the DVH calculation systems. While analytical DVH calculations for a single source were used as a reference in brachytherapy, 7,13 we are not aware of a similar approach reported for external beam DVH validation.…”

A simple DVH generation technique for various radiotherapy treatment planning systems for an independent information system

“…Their main benefit to complex treatment plans is providing summarized data of the 3D dose distribution as a graph and statistical format for structures. It is a useful tool for comparison of various treatment plans from different planning techniques or multiple treatment planning systems (TPSs) [3][4][5][6][7].…”