Comparative study of old and new versions of treatment planning system using dose volume histogram indices of clinical plans

Abstract

Recently, Eclipse treatment planning system (TPS) version 8.8 was upgraded to the latest version 13.6. It is customary that the vendor gives training on how to upgrade the existing software to the new version. However, the customer is provided less inner details about changes in the new software version. According to manufacturer, accuracy of point dose calculations and irregular treatment planning is better in the new version (13.6) compared to the old version (8.8). Furthermore, the new version uses voxel-based calculations while the earlier version used point dose calculations. Major difference in intensity-modulated radiation therapy (IMRT) plans was observed between the two versions after re-optimization and re-calculations. However, minor difference was observed for IMRT cases after performing only re-calculations. It is recommended TPS quality assurance to be performed after any major upgrade of software. This can be done by performing dose calculation comparisons in TPS. To assess the difference between the versions, 25 clinical cases from the old version were compared keeping all the patient data intact including the monitor units and comparing the differences in dose calculations using dose volume histogram (DVH) analysis. Along with DVH analysis, uniformity index, conformity index, homogeneity index, and dose spillage index were also compared for both versions. The results of comparative study are presented in this paper.

Validation of a software upgrade in a monte carlo treatment planning system by comparison of plans in different versions

“…Their results had shown that the plan quality of new Eclipse ™ V13.6 was maintained with almost same doses as compared to old version 8.8. [ 27 ]…”

A comparative study of RapidArc and intensity-modulated radiotherapy plan quality for cervical cancer treatment

“…The dose coverage calculated in the present study is defined as the ratio of Dmin to PD. [18] The plan is considered acceptable if TV completely covers 90% of prescription isodose. There will be a minor deviation if 80% of PD encompass TV.…”

Evaluation of various dose homogeneity indices for treatment of patients with cervix cancer using intensity-modulated radiation therapy technique

“…A smaller value of HI indicates a more homogenous dose distribution. 8,12,20,22,23 The homogeneity volume index (HVI), represented as HI D, indicates homogeneity of the dose distribution inside the target volume and is calculated as a ratio of ID within target volume to the product of target volume and prescribed dose.…”