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

TL;DR

This paper presents a straightforward method to generate reproducible dose-volume histogram (DVH) data from various radiotherapy treatment planning systems, improving consistency and compatibility for independent information systems.

Contribution

A simple, effective technique using supersampling and interpolation to produce consistent DVH values across different TPSs, addressing discrepancies and enabling unified data management.

Findings

The proposed method yields smaller discrepancies than commercial tools.

Discrepancies increase for small-volume structures like the eye and lens.

The technique is practical for independent and integrated radiotherapy data systems.

Abstract

In recent years, the use of PACS for radiation therapy has become the norm in hospital environment and has suggested for collecting data and management from different TPSs with DICOM objects. However, some TPS does not provide the DVH exportation with text or other format. In addition, plan review systems for various TPSs often allow DVH recalculation with different algorithms. These algorithms result in the inevitable discrepancy between the values obtained with the recalculation and those obtained with TPS itself. The purpose of this study was to develop a simple method for generating reproducible DVH values obtained from the TPSs. Treatment planning information including structures and delivered dose was exported by the DICOM format from planning systems. The supersampling and trilinear interpolation methods were employed to calculate DVH data from 35 treatment plans. The discrepancies between DVHs extracted from each TPS and the proposed calculation method were evaluated with respect to the supersampling ratio. The volume, minimum dose, maximum dose, and mean dose were compared. The variation of DVHs from multiple TPSs was compared with a commercially available treatment planning comparison tool. The overall comparisons of the volume, minimum dose, maximum dose, and mean dose showed that the proposed method generated relatively smaller discrepancies compared with TPS than those by MIM software and TPS. As the structure volume decreased, the overall percent difference increased. Most large difference was observed in the small organs such as eye ball, lens, optic nerve which had below 10 cc volume. A simple and useful technique was developed to generate DVH with acceptable error from a proprietary TPS. This study provides the convenient and common framework which allows to use a single well-managed storage solution for the independent information system.