Automate IMRT Planning in Pinnacle: A Study in Head-And-Neck Cancer
M Kusters1*, K Bzdusek2, P Kumar3, P van Kollenburg1, M Kunze-Busch1, H Kaanders1, (1) Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands, (2) Philips Healthcare, Fitchburg, WI, (3) Philips Innovation Campus, Bangalore, IndiaSU-E-T-590 Sunday 3:00PM - 6:00PM Room: Exhibit Hall
Purpose: We investigated whether the auto-planning prototype included in a research version of Pinnacle 9.700 (Philips Healthcare) is able to create treatment plans with consistent quality, independent of the experience of the planner using a single template.
Methods:The auto-planning module requires the user to define a template with prioritized optimization goals for PTV-coverage and dose constraints for organ at risks (OARs). Prioritized optimization goals are used by the auto-planning engine to formulate optimization objectives.
Multiple optimization loops iteratively reformulate and adjust the optimization objectives to meet the goals and further lower dose to OAR with minimal compromise to the target coverage. Dose conformality and uniformity to the target(s) are also controlled automatically.
The quality of ten oropharynx IMRT auto-planned plans was evaluated by calculating the target coverage (V95) and conformity index (CI) of the PTVs (prescribed dose to PTV> was 50.3 Gy and 68 Gy to PTV<), the maximum dose to the cord, and mean dose to parotids and oral cavity. Efficiency was evaluated by measuring the total planning time.
Results: All auto-planned plans fulfilled the clinical dose criteria for OARs and PTV coverage. The average V95 and CI to PTV> were 99.1% ⁺/₋1.6% and 0.8 ⁺/₋0.1, respectively and to PTV< 96.2% ⁺/₋1.5% and 0.6 ⁺/₋0.1, respectively. The average maximum dose to the cord was 44.9 ⁺/₋2.0 Gy, average mean dose to the parotids was 28.4 ⁺/₋4.5 Gy and 33.7 ⁺/₋7.0 Gy to the oral cavity. Total planning time could be reduced from about 4 hours to less than 30 minutes.
Conclusion: The auto-planning module generates plans with consistent quality and reduces total planning time significantly. The tool is designed to automatically perform many of the manual operations in the current IMRT process, any further optimization for an individual patient has to be done outside auto-plan.