Purpose: Recently, the ability to perform patient-specific quality assurance (PSQA) with the ArcCHECK (AC) was integrated with Sun Nuclear’s SunCHECK software. SunCHECK Patient (SCP) contains an independent dose calculation model and automatically creates a QA-plan when the plan is designated for AC measurement. While the basic features of the current software, SNC Patient (SNC-P), exist in SCP, plans cannot be measurement adjusted (MA) when dose distributions exceed the AC limitations. This initial evaluation of AC/SCP combination assesses the impact of partial measurements and use of an independent QA-plan on PSQA passing rates.
Methods: MA plans in SNC-P were identified (“flips”, shifts, and double density). Plans were delivered with and without adjustment (WA) and compared to TPS QA-plans in SNC-P using the gamma parameters of: 3%/2mm, absolute dose, global%, 10% threshold; ≥95% to pass. Total number of passing, failing, and evaluated points were collected. Plans were additionally measured WA in SCP using the same criteria, but compared to the SCP QA-plan. MA passing rates and points were compared to WA. SCP results were compared to MA and WA SNC-P measurements.
Results: Fifteen MA plans were identified. On average, WA measurements evaluated 23% less points than the MA, but the difference in passing rates lacked clinical significance (0.6% Abs(MA-WA)). However, the SCP passing rates were on average 1.8% higher than SNC-P passing rates. Two-thirds of plans that did not pass in SNC-P WA using TPS plans, passed in SCP. One plan passed in SNC-P and failed by 0.5% in SCP.
Conclusion: While our current practice is to measure the entire dose distribution, passing rates were minimally affected by partial sampling in SNC-P and SCP. However, using a SCP generated QA-plan had a clinical impact on passing rates and requires further investigation to determine the appropriate method of evaluation.
Funding Support, Disclosures, and Conflict of Interest: Tufts Medical Center has a research agreement with Sun Nuclear Corp.