Abstract
In this paper, we study several interesting intensity map splitting (IMSp) problems that arise in Intensity-Modulated Radiation Therapy (IMRT), a state-of-the-art radiation therapy technique for cancer treatments. In current clinical practice, a multi-leaf collimator (MLC) with a maximum leaf spread is used to deliver the prescribed intensity maps (IMs). However, the maximum leaf spread of an MLC may require to split a large intensity map into several abutting sub-IMs each being delivered separately, which results in prolonged treatment time. Few IM splitting techniques reported in the literature has addressed the issue of treatment delivery efficiency for large IMs. We develop a unified approach for solving the IMSp problems while minimizing the total beam-on time in various settings. Our basic idea is to formulate the IMSp problem as computing a k-link shortest path in a directed acyclic graph. We carefully characterize the intrinsic structures of the graph, yielding efficient algorithms for the IMSp problems.
This research was supported in part by a faculty start-up fund from the University of Iowa, Iowa City, IA 52242, USA. Part of this work was done at the Department of Computer Science, the University of Texas – Pan American, Edinburg, TX 78541.
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Wu, X. (2005). Efficient Algorithms for Intensity Map Splitting Problems in Radiation Therapy. In: Wang, L. (eds) Computing and Combinatorics. COCOON 2005. Lecture Notes in Computer Science, vol 3595. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11533719_51
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DOI: https://doi.org/10.1007/11533719_51
Publisher Name: Springer, Berlin, Heidelberg
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