Abstract:
:The formulation of intensity modulated radiation therapy (IMRT) planning aspects frequently uses the dose-volume histogram (DVH), whereas plan computations often happen in the more desirable convex IMRT optimization framework. Inspired by a recent publication of Zinchenko et al (2008 Phys. Med. Biol. 53 3231-50), this work addresses the integration of DVH-based planning aspects into this framework from a general point of view. It first provides the basic mathematical requirements on the evaluation functions in order to support such an incorporation. Then it introduces the condition number as a description for how precisely DVH-based planning aspects can be reformulated in terms of evaluation functions. Exemplary numerical studies for the generalized equivalent uniform dose and a physical constraint function show the influence of function parameter values and DVH approximation on the condition number. The work concludes by formulating the aspects that should be taken into account for an appropriate integration of DVH-based planning aspects.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Kratt K,Scherrer Adoi
10.1088/0031-9155/54/12/N02subject
Has Abstractpub_date
2009-06-21 00:00:00pages
N239-46issue
12eissn
0031-9155issn
1361-6560pii
S0031-9155(09)89148-3journal_volume
54pub_type
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