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A simple plan evaluation index based on the dose to critical structures in radiotherapy
Ramachandran Prabhakar1, Goura K Rath
1Department of Radiation Oncology, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi, India.
Journal of Medical Physics
|January 10, 2012
Summary
A new Plan Normal tissue complication Index (PNI) aids radiotherapy. This index evaluates treatment plans by assessing doses to critical structures, improving patient safety and plan selection.
Area of Science:
- Radiation oncology
- Medical physics
- Radiotherapy planning
Background:
- Dose to critical structures is crucial in radiotherapy treatment plan evaluation.
- Accurate assessment of these doses presents a significant challenge in planning.
Purpose of the Study:
- To introduce a simple index, the Plan Normal tissue complication Index (PNI), for evaluating radiotherapy treatment plans.
- To assess the utility of PNI across various critical treatment sites.
Main Methods:
- Developed a software program, PNIcalc, to compute PNI.
- Utilized dose-volume histogram data and established tissue tolerance data.
- Compared PNI results with QUANTEC recommendations (2010).
Main Results:
- PNI provided a comprehensive overview of critical structure doses in studied cases.
- The index identified fractional volumes exceeding tolerance limits.
- PNI facilitated quick comparison and selection of treatment plans with reduced critical organ doses.
Conclusions:
- The proposed Plan Normal tissue complication Index (PNI) is a valuable tool for routine radiotherapy plan evaluation.
- PNI aids in selecting plans that minimize dose to surrounding critical structures.
- This index can enhance the overall quality and safety of external beam radiotherapy.
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