Comparing planning time, delivery time and plan quality for IMRT, RapidArc and Tomotherapy

Area of Science:

• Radiation Oncology
• Medical Physics
• Radiotherapy Planning

Background:

• Optimizing radiation therapy techniques is crucial for improving treatment efficacy and patient outcomes.
• Different radiotherapy modalities, including Intensity-Modulated Radiation Therapy (IMRT), RapidArc, and TomoTherapy, offer distinct advantages and challenges in treatment planning.

Purpose of the Study:

• To compare plan quality, planning time, and estimated delivery time across various radiotherapy techniques.
• To evaluate 5- and 9-field sliding window IMRT, single and dual arc RapidArc, and TomoTherapy using phantom-based assessments.

Main Methods:

• Radiotherapy plans were generated for four phantoms using 5- and 9-field IMRT, single/dual arc RapidArc, and TomoTherapy.
• Plan evaluation included dose-volume constraints, homogeneity index, conformity index, planning/delivery times, integral dose, and critical volume doses (2 Gy, 5 Gy).

Main Results:

• TomoTherapy achieved the highest percentage of optimization criteria met across phantoms (0-67%), followed by RapidArc (0-25%), while IMRT met none.
• TomoTherapy yielded the most homogeneous dose distributions but had longer planning/treatment times, lower conformity, and higher integral dose.
• RapidArc demonstrated superior plan quality compared to IMRT for the evaluated scenarios.

Conclusions:

• TomoTherapy excels in plan quality and dose conformity in the axial plane but may increase dose to tissues superior/inferior to the target.
• RapidArc offers better plan quality than IMRT for the tested cases.
• The choice of technique involves trade-offs between plan quality, planning efficiency, and delivery time.