Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty
In radiation therapy, intensity maps involving margins have long been used to counteract the effects of dose blurring arising from motion. More recently, intensity maps with increased intensity near the edge of the tumour (edge enhancements) have been studied to evaluate their ability to offset simi...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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IOP Publishing
2012
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| Online Access: | http://hdl.handle.net/1721.1/71949 https://orcid.org/0000-0003-2658-8239 |
| _version_ | 1811071627570446336 |
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| author | Chan, Timothy C. Y. Tsitsiklis, John N. Bortfeld, Thomas |
| author2 | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science |
| author_facet | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Chan, Timothy C. Y. Tsitsiklis, John N. Bortfeld, Thomas |
| author_sort | Chan, Timothy C. Y. |
| collection | MIT |
| description | In radiation therapy, intensity maps involving margins have long been used to counteract the effects of dose blurring arising from motion. More recently, intensity maps with increased intensity near the edge of the tumour (edge enhancements) have been studied to evaluate their ability to offset similar effects that affect tumour coverage. In this paper, we present a mathematical methodology to derive margin and edge-enhanced intensity maps that aim to provide tumour coverage while delivering minimum total dose. We show that if the tumour is at most about twice as large as the standard deviation of the blurring distribution, the optimal intensity map is a pure scaling increase of the static intensity map without any margins or edge enhancements. Otherwise, if the tumour size is roughly twice (or more) the standard deviation of motion, then margins and edge enhancements are preferred, and we present formulae to calculate the exact dimensions of these intensity maps. Furthermore, we extend our analysis to include scenarios where the parameters of the motion distribution are not known with certainty, but rather can take any value in some range. In these cases, we derive a similar threshold to determine the structure of an optimal margin intensity map. |
| first_indexed | 2024-09-23T08:54:10Z |
| format | Article |
| id | mit-1721.1/71949 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T08:54:10Z |
| publishDate | 2012 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | mit-1721.1/719492022-09-30T12:00:40Z Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty Chan, Timothy C. Y. Tsitsiklis, John N. Bortfeld, Thomas Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology. Laboratory for Information and Decision Systems Tsitsiklis, John N. Tsitsiklis, John N. In radiation therapy, intensity maps involving margins have long been used to counteract the effects of dose blurring arising from motion. More recently, intensity maps with increased intensity near the edge of the tumour (edge enhancements) have been studied to evaluate their ability to offset similar effects that affect tumour coverage. In this paper, we present a mathematical methodology to derive margin and edge-enhanced intensity maps that aim to provide tumour coverage while delivering minimum total dose. We show that if the tumour is at most about twice as large as the standard deviation of the blurring distribution, the optimal intensity map is a pure scaling increase of the static intensity map without any margins or edge enhancements. Otherwise, if the tumour size is roughly twice (or more) the standard deviation of motion, then margins and edge enhancements are preferred, and we present formulae to calculate the exact dimensions of these intensity maps. Furthermore, we extend our analysis to include scenarios where the parameters of the motion distribution are not known with certainty, but rather can take any value in some range. In these cases, we derive a similar threshold to determine the structure of an optimal margin intensity map. National Cancer Institute (U.S.) (grant R01-CA103904) National Cancer Institute (U.S.) (grant R01-CA118200) Natural Sciences and Engineering Research Council of Canada (NSERC) Siemens Aktiengesellschaft Massachusetts Institute of Technology. Hugh Hampton Young Memorial Fund fellowship 2012-08-01T19:54:24Z 2012-08-01T19:54:24Z 2009-12 2009-11 Article http://purl.org/eprint/type/JournalArticle 0031-9155 1361-6560 http://hdl.handle.net/1721.1/71949 Chan, Timothy C Y, John N Tsitsiklis, and Thomas Bortfeld. “Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty.” Physics in Medicine and Biology 55.2 (2010): 515-533. https://orcid.org/0000-0003-2658-8239 en_US http://dx.doi.org/10.1088/0031-9155/55/2/012 Physics in Medicine and Biology Creative Commons Attribution-Noncommercial-Share Alike 3.0 http://creativecommons.org/licenses/by-nc-sa/3.0/ application/pdf IOP Publishing Tsitsiklis via Amy Stout |
| spellingShingle | Chan, Timothy C. Y. Tsitsiklis, John N. Bortfeld, Thomas Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty |
| title | Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty |
| title_full | Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty |
| title_fullStr | Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty |
| title_full_unstemmed | Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty |
| title_short | Optimal margin and edge-enhanced intensity maps in the presence of motion and uncertainty |
| title_sort | optimal margin and edge enhanced intensity maps in the presence of motion and uncertainty |
| url | http://hdl.handle.net/1721.1/71949 https://orcid.org/0000-0003-2658-8239 |
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