The novel universal conformity index and unconformity index algorithms for radiotherapy treatment plans


      The purpose of the study is that introduce novel universal Conformity Index (CI) and Unconformity Index (UCIs) Algorithms that can be used for all radiotherapy treatment planning methods. The applicability of existing CIs has been reviewed and analyzed for each radiotherapy plan dose distribution. Novel CI and UCIs have been derived in this study to complement the calculation deficiencies. The novel CI evaluation software has been developed using these algorithms with Eclipse Scripting Application Programing Interface (ESAPI). Also, this software has been tested at clinically case. There are deficiencies in existing CI formulas. Some of currently used CIs only consider the irradiated healthy tissue volume, whereas others solely consider the irradiated tumor volume. The existing CIs can't reveal the cause of unconformity and calculate the unconformity magnitude. In the current study, CI evaluation software were successfully run integrated with TPS. Novel CI and UCIs algorithms introduced in the current study overcome all calculation deficiencies of existing CIs. Results have showed that the novel CI yielding correct results when cold spots has occurred in the tumor volume (TV) and/or healthy tissues has been irradiated was completely compatible with the accepted definitions of the conformity index. Also, it is universally applicable. Besides, cause and magnitude of unconformity in plans can accurately be revealed with the novel UCI algorithms. Thus, what to be done to increase the conformity is well addressed. Novel CI and UCIs can effectively be used as optimization tool to create the best radiotherapy dose distribution.


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