Encrypted login | home

Program Information

Development and Verification of Automatic Reading Dose of Interest From Eclipse's DVH


Q Wu

Q Wu1*, (1) Department of Radiation Oncology, Beijing Hospital, Ministry of Health, Beijing 100730, China

Presentations

SU-E-T-641 Sunday 3:00PM - 6:00PM Room: Exhibit Hall

Purpose: According to clinical and research requirement, we develop a function of automatic reading dose of interest from dose volume histogram(DVH), to replace the traditional method with a mouse one by one point, and it's also verified.

Methods: The DVH automatic reading function will be developed in an in-house developed radiotherapy information management system(RTIMS), which is based on Apache+PHP+MySQL. A DVH ASCII file is exported from Varian Eclipse V8.6, which includes the following contents: 1. basic information of patient; 2. dose information of plan; 3. dose information of structures, including basic information and dose volume data of target volume and organ at risk. And the default exported dose volume data also includes relative doses by 1% step and corresponding absolute doses and cumulative relative volumes, and the volumes are 4 decimal fraction. Clinically, we often need read the doses of some integer percent volumes, such as D50 and D30. So it couldn't be directly obtained from the above data, but we can use linear interpolation bye the near volumes and doses: Dx=D2-(V2-Vx)*(D2-D1)/(V2-V1), and program a function to search, read and calculate the corresponding data. And the doses of all preseted volume of interest of all structures can be automatically read one by one patient, and saved as a CSV file. To verify it, we select 24 IMRT plans for prostate cancer, and doses of interest are PTV D98/D95/D5/D2, bladder D30/D50, and rectum D25/D50. Two groups of data, using the automatic reading method(ARM) and pointed dose method(PDM), are analyzed with SPSS 16. The absolute difference=D_ARM-D_PDM, relative difference=absolute difference*100%/prescription dose(7600cGy).

Results: The differences are as following: PTV D98/D95/D5/D2: -0.04%/-0.04%/0.13%/0.19%, bladder D30/D50: -0.02%/0.01%, and rectum D25/D50: 0.03%/0.01%.

Conclusion: Using this function, the error is very small, and can be neglected. It could greatly improve the efficiency of clinical work.

Funding Support, Disclosures, and Conflict of Interest: Project supported by the National Natural Science Foundation of China (Grant No.81101694).


Contact Email: