AbstractID: 9173 Title: A Statistical Method for Analyzing and Verifying Dynamic and
Static IMRT Delivery
A statistical test method was developed for verifying and analyzing intensity-modulated
fluence distributions. The method was used to analyze transmission dose measurements
using either radiographic films or flat-panel electronic imaging devices. A filtered
estimate method was developed to eliminate point-spread kernel dependencies in
analyzing detector response signals for intensity-modulated field measurements. A χ2confidence level test method was developed to detect the discrepancies between the
measured and the prescribed IMRT fluence distributions. The method was tested on
rotational and fixed-beam IMRT deliveries. We intentionally introduced errors that cause
systematic variations in segment monitor units and/or segment shapes to show the
effectiveness of the method. We compared the χ2-confidence level test method with the
linear correlation coefficient method. We found that our method is insensitive to
hardware-related parameters such as beam energies, number of field segments, and static
or dynamic delivery modes. We found that the χ2-confidence level test was significantly
more sensitive than the linear correlation method in detecting small segment errors. In
conclusion, we demonstrated a useful method for quantitatively verifying and analyzing
rotational and fixed-beam IMRT treatment deliveries.
Supported in part by Department of Defense and Institutional Intramural Grant Office