Monte Carlo based IMRT dose verification using MLC log files and R/V outputs
Conventional IMRT dose verification using film and ion chamber measurements is useful but limited with respect to the actual dose distribution received by the patient. The Monte Carlo simulation has been introduced as an independent dose verification tool for IMRT using the patient CT data and MLC l...
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| creator | Luo, Wei Li, Jinsheng Price, Robert A. Chen, Lili Yang, Jie Fan, Jiajin Chen, Zuoqun McNeeley, Shawn Xu, Xiu Ma, Chang-Ming |
| description | Conventional IMRT dose verification using film and ion chamber measurements is useful but limited with respect to the actual dose distribution received by the patient. The Monte Carlo simulation has been introduced as an independent dose verification tool for IMRT using the patient CT data and MLC leaf sequence files, which validates the dose calculation accuracy but not the plan delivery accuracy. In this work, we propose a Monte Carlo based IMRT dose verification method that reconstructs the patient dose distribution using the patient CT, actual beam data based on the information from the record and verify system (R/V), and the MLC log files obtained during dose delivery that record the MLC leaf positions and MUs delivered. Comparing the Monte Carlo dose calculation with the original IMRT plan using these data simultaneously validates the accuracy of both the IMRT dose calculation and beam delivery. Such log file based Monte Carlo simulations are expected to be employed as a useful and efficient IMRT QA modality to validate the dose delivered to the patient. We have run Monte Carlo simulations for eight IMRT prostate plans using this method and the results for the target dose were consistent with the original CORVUS treatment plans to within 3.0% and 2.0% with and without heterogeneity corrections in the dose calculation. However, significant dose deviations in nearby critical structures have been observed. The results showed that up to 9.0% of the bladder dose and up to 38.0% of the rectum dose, to which leaf position errors were found to contribute
<
2
%
, were underestimated by the CORVUS treatment planning system. The concept of average leaf position error has been defined to analyze MLC leaf position errors for an IMRT plan. A linear correlation between the target dose error and the average position error has been found based on log file based Monte Carlo simulations, showing that an average position error of
0.2
mm
can result in a target dose error of about 1.0%. |
| doi_str_mv | 10.1118/1.2208916 |
| format | Article |
| fullrecord | <record><control><sourceid>wiley_scita</sourceid><recordid>TN_cdi_wiley_primary_10_1118_1_2208916_MP8916</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>MP8916</sourcerecordid><originalsourceid>FETCH-LOGICAL-c4196-feefa97ca5e0ac08777aac31ebfc6b669f3145a157258d2491d69051557fbe373</originalsourceid><addsrcrecordid>eNp9kE1LwzAYgIMobk4P_gEJeFLoljQfbY5S_Bi0KGN6LWmazEptStNO9u_tbEEvkxzey8PzvnkAuMRojjEOF3ju-ygUmB-BqU8D4lEfiWMwRUhQz6eITcCZcx8IIU4YOgUTzEMRUo6mIE5s1WoYyaa0MJNO53CZrNYwt07DrW4KUyjZFraCnSuqDUziCJZ2A01RagdllcPV4g3arq271p2DEyNLpy_GOQOvD_fr6MmLnx-X0V3sKYoF94zWRopASaaRVCgMgkBKRbDOjOIZ58IQTJnELPBZmPtU4JwLxDBjgck0CcgMXA9e69oidapotXpXtqq0atO-BCN-_2bgZqBUY51rtEnrpviUzS7FKN13S3E6duvZq4Gtu-xT57_kGKoHvAH46j--O2xKk5dReDvw--t-Av67_SC8tc0feZ0b8g0SP48q</addsrcrecordid><sourcetype>Open Access Repository</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype></control><display><type>article</type><title>Monte Carlo based IMRT dose verification using MLC log files and R/V outputs</title><source>MEDLINE</source><source>Wiley Journals</source><creator>Luo, Wei ; Li, Jinsheng ; Price, Robert A. ; Chen, Lili ; Yang, Jie ; Fan, Jiajin ; Chen, Zuoqun ; McNeeley, Shawn ; Xu, Xiu ; Ma, Chang-Ming</creator><creatorcontrib>Luo, Wei ; Li, Jinsheng ; Price, Robert A. ; Chen, Lili ; Yang, Jie ; Fan, Jiajin ; Chen, Zuoqun ; McNeeley, Shawn ; Xu, Xiu ; Ma, Chang-Ming</creatorcontrib><description>Conventional IMRT dose verification using film and ion chamber measurements is useful but limited with respect to the actual dose distribution received by the patient. The Monte Carlo simulation has been introduced as an independent dose verification tool for IMRT using the patient CT data and MLC leaf sequence files, which validates the dose calculation accuracy but not the plan delivery accuracy. In this work, we propose a Monte Carlo based IMRT dose verification method that reconstructs the patient dose distribution using the patient CT, actual beam data based on the information from the record and verify system (R/V), and the MLC log files obtained during dose delivery that record the MLC leaf positions and MUs delivered. Comparing the Monte Carlo dose calculation with the original IMRT plan using these data simultaneously validates the accuracy of both the IMRT dose calculation and beam delivery. Such log file based Monte Carlo simulations are expected to be employed as a useful and efficient IMRT QA modality to validate the dose delivered to the patient. We have run Monte Carlo simulations for eight IMRT prostate plans using this method and the results for the target dose were consistent with the original CORVUS treatment plans to within 3.0% and 2.0% with and without heterogeneity corrections in the dose calculation. However, significant dose deviations in nearby critical structures have been observed. The results showed that up to 9.0% of the bladder dose and up to 38.0% of the rectum dose, to which leaf position errors were found to contribute
<
2
%
, were underestimated by the CORVUS treatment planning system. The concept of average leaf position error has been defined to analyze MLC leaf position errors for an IMRT plan. A linear correlation between the target dose error and the average position error has been found based on log file based Monte Carlo simulations, showing that an average position error of
0.2
mm
can result in a target dose error of about 1.0%.</description><identifier>ISSN: 0094-2405</identifier><identifier>EISSN: 2473-4209</identifier><identifier>DOI: 10.1118/1.2208916</identifier><identifier>PMID: 16898460</identifier><identifier>CODEN: MPHYA6</identifier><language>eng</language><publisher>United States: American Association of Physicists in Medicine</publisher><subject>ACCURACY ; Anatomy ; average leaf position error ; biological organs ; BLADDER ; Computer Simulation ; COMPUTERIZED SIMULATION ; CORRECTIONS ; Data Interpretation, Statistical ; dose verification ; Dose-Response Relationship, Radiation ; dosimetry ; Error analysis ; ERRORS ; Humans ; IMRT quality assurance (QA) ; Intensity modulated radiation therapy ; intensity modulation ; IONIZATION CHAMBERS ; log file based Monte Carlo simulation ; Male ; Medical treatment planning ; MLC log file ; MONTE CARLO METHOD ; Monte Carlo methods ; Multileaf collimators ; PATIENTS ; PROSTATE ; Prostatic Neoplasms - radiotherapy ; QUALITY ASSURANCE ; Quality assurance in radiotherapy ; RADIATION DOSE DISTRIBUTIONS ; RADIATION DOSES ; radiation therapy ; RADIOLOGY AND NUCLEAR MEDICINE ; Radiometry - methods ; RADIOTHERAPY ; Radiotherapy Dosage ; Radiotherapy Planning, Computer-Assisted - methods ; Radiotherapy, Intensity-Modulated - methods ; Record and verify systems and applications ; RECTUM ; Reproducibility of Results ; Sequence analysis ; Software ; Treatment strategy ; VERIFICATION</subject><ispartof>Medical physics (Lancaster), 2006-07, Vol.33 (7), p.2557-2564</ispartof><rights>American Association of Physicists in Medicine</rights><rights>2006 American Association of Physicists in Medicine</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c4196-feefa97ca5e0ac08777aac31ebfc6b669f3145a157258d2491d69051557fbe373</citedby><cites>FETCH-LOGICAL-c4196-feefa97ca5e0ac08777aac31ebfc6b669f3145a157258d2491d69051557fbe373</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://onlinelibrary.wiley.com/doi/pdf/10.1118%2F1.2208916$$EPDF$$P50$$Gwiley$$H</linktopdf><linktohtml>$$Uhttps://onlinelibrary.wiley.com/doi/full/10.1118%2F1.2208916$$EHTML$$P50$$Gwiley$$H</linktohtml><link.rule.ids>230,314,780,784,885,1417,27924,27925,45574,45575</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/16898460$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink><backlink>$$Uhttps://www.osti.gov/biblio/20853232$$D View this record in Osti.gov$$Hfree_for_read</backlink></links><search><creatorcontrib>Luo, Wei</creatorcontrib><creatorcontrib>Li, Jinsheng</creatorcontrib><creatorcontrib>Price, Robert A.</creatorcontrib><creatorcontrib>Chen, Lili</creatorcontrib><creatorcontrib>Yang, Jie</creatorcontrib><creatorcontrib>Fan, Jiajin</creatorcontrib><creatorcontrib>Chen, Zuoqun</creatorcontrib><creatorcontrib>McNeeley, Shawn</creatorcontrib><creatorcontrib>Xu, Xiu</creatorcontrib><creatorcontrib>Ma, Chang-Ming</creatorcontrib><title>Monte Carlo based IMRT dose verification using MLC log files and R/V outputs</title><title>Medical physics (Lancaster)</title><addtitle>Med Phys</addtitle><description>Conventional IMRT dose verification using film and ion chamber measurements is useful but limited with respect to the actual dose distribution received by the patient. The Monte Carlo simulation has been introduced as an independent dose verification tool for IMRT using the patient CT data and MLC leaf sequence files, which validates the dose calculation accuracy but not the plan delivery accuracy. In this work, we propose a Monte Carlo based IMRT dose verification method that reconstructs the patient dose distribution using the patient CT, actual beam data based on the information from the record and verify system (R/V), and the MLC log files obtained during dose delivery that record the MLC leaf positions and MUs delivered. Comparing the Monte Carlo dose calculation with the original IMRT plan using these data simultaneously validates the accuracy of both the IMRT dose calculation and beam delivery. Such log file based Monte Carlo simulations are expected to be employed as a useful and efficient IMRT QA modality to validate the dose delivered to the patient. We have run Monte Carlo simulations for eight IMRT prostate plans using this method and the results for the target dose were consistent with the original CORVUS treatment plans to within 3.0% and 2.0% with and without heterogeneity corrections in the dose calculation. However, significant dose deviations in nearby critical structures have been observed. The results showed that up to 9.0% of the bladder dose and up to 38.0% of the rectum dose, to which leaf position errors were found to contribute
<
2
%
, were underestimated by the CORVUS treatment planning system. The concept of average leaf position error has been defined to analyze MLC leaf position errors for an IMRT plan. A linear correlation between the target dose error and the average position error has been found based on log file based Monte Carlo simulations, showing that an average position error of
0.2
mm
can result in a target dose error of about 1.0%.</description><subject>ACCURACY</subject><subject>Anatomy</subject><subject>average leaf position error</subject><subject>biological organs</subject><subject>BLADDER</subject><subject>Computer Simulation</subject><subject>COMPUTERIZED SIMULATION</subject><subject>CORRECTIONS</subject><subject>Data Interpretation, Statistical</subject><subject>dose verification</subject><subject>Dose-Response Relationship, Radiation</subject><subject>dosimetry</subject><subject>Error analysis</subject><subject>ERRORS</subject><subject>Humans</subject><subject>IMRT quality assurance (QA)</subject><subject>Intensity modulated radiation therapy</subject><subject>intensity modulation</subject><subject>IONIZATION CHAMBERS</subject><subject>log file based Monte Carlo simulation</subject><subject>Male</subject><subject>Medical treatment planning</subject><subject>MLC log file</subject><subject>MONTE CARLO METHOD</subject><subject>Monte Carlo methods</subject><subject>Multileaf collimators</subject><subject>PATIENTS</subject><subject>PROSTATE</subject><subject>Prostatic Neoplasms - radiotherapy</subject><subject>QUALITY ASSURANCE</subject><subject>Quality assurance in radiotherapy</subject><subject>RADIATION DOSE DISTRIBUTIONS</subject><subject>RADIATION DOSES</subject><subject>radiation therapy</subject><subject>RADIOLOGY AND NUCLEAR MEDICINE</subject><subject>Radiometry - methods</subject><subject>RADIOTHERAPY</subject><subject>Radiotherapy Dosage</subject><subject>Radiotherapy Planning, Computer-Assisted - methods</subject><subject>Radiotherapy, Intensity-Modulated - methods</subject><subject>Record and verify systems and applications</subject><subject>RECTUM</subject><subject>Reproducibility of Results</subject><subject>Sequence analysis</subject><subject>Software</subject><subject>Treatment strategy</subject><subject>VERIFICATION</subject><issn>0094-2405</issn><issn>2473-4209</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2006</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNp9kE1LwzAYgIMobk4P_gEJeFLoljQfbY5S_Bi0KGN6LWmazEptStNO9u_tbEEvkxzey8PzvnkAuMRojjEOF3ju-ygUmB-BqU8D4lEfiWMwRUhQz6eITcCZcx8IIU4YOgUTzEMRUo6mIE5s1WoYyaa0MJNO53CZrNYwt07DrW4KUyjZFraCnSuqDUziCJZ2A01RagdllcPV4g3arq271p2DEyNLpy_GOQOvD_fr6MmLnx-X0V3sKYoF94zWRopASaaRVCgMgkBKRbDOjOIZ58IQTJnELPBZmPtU4JwLxDBjgck0CcgMXA9e69oidapotXpXtqq0atO-BCN-_2bgZqBUY51rtEnrpviUzS7FKN13S3E6duvZq4Gtu-xT57_kGKoHvAH46j--O2xKk5dReDvw--t-Av67_SC8tc0feZ0b8g0SP48q</recordid><startdate>200607</startdate><enddate>200607</enddate><creator>Luo, Wei</creator><creator>Li, Jinsheng</creator><creator>Price, Robert A.</creator><creator>Chen, Lili</creator><creator>Yang, Jie</creator><creator>Fan, Jiajin</creator><creator>Chen, Zuoqun</creator><creator>McNeeley, Shawn</creator><creator>Xu, Xiu</creator><creator>Ma, Chang-Ming</creator><general>American Association of Physicists in Medicine</general><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>OTOTI</scope></search><sort><creationdate>200607</creationdate><title>Monte Carlo based IMRT dose verification using MLC log files and R/V outputs</title><author>Luo, Wei ; Li, Jinsheng ; Price, Robert A. ; Chen, Lili ; Yang, Jie ; Fan, Jiajin ; Chen, Zuoqun ; McNeeley, Shawn ; Xu, Xiu ; Ma, Chang-Ming</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c4196-feefa97ca5e0ac08777aac31ebfc6b669f3145a157258d2491d69051557fbe373</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2006</creationdate><topic>ACCURACY</topic><topic>Anatomy</topic><topic>average leaf position error</topic><topic>biological organs</topic><topic>BLADDER</topic><topic>Computer Simulation</topic><topic>COMPUTERIZED SIMULATION</topic><topic>CORRECTIONS</topic><topic>Data Interpretation, Statistical</topic><topic>dose verification</topic><topic>Dose-Response Relationship, Radiation</topic><topic>dosimetry</topic><topic>Error analysis</topic><topic>ERRORS</topic><topic>Humans</topic><topic>IMRT quality assurance (QA)</topic><topic>Intensity modulated radiation therapy</topic><topic>intensity modulation</topic><topic>IONIZATION CHAMBERS</topic><topic>log file based Monte Carlo simulation</topic><topic>Male</topic><topic>Medical treatment planning</topic><topic>MLC log file</topic><topic>MONTE CARLO METHOD</topic><topic>Monte Carlo methods</topic><topic>Multileaf collimators</topic><topic>PATIENTS</topic><topic>PROSTATE</topic><topic>Prostatic Neoplasms - radiotherapy</topic><topic>QUALITY ASSURANCE</topic><topic>Quality assurance in radiotherapy</topic><topic>RADIATION DOSE DISTRIBUTIONS</topic><topic>RADIATION DOSES</topic><topic>radiation therapy</topic><topic>RADIOLOGY AND NUCLEAR MEDICINE</topic><topic>Radiometry - methods</topic><topic>RADIOTHERAPY</topic><topic>Radiotherapy Dosage</topic><topic>Radiotherapy Planning, Computer-Assisted - methods</topic><topic>Radiotherapy, Intensity-Modulated - methods</topic><topic>Record and verify systems and applications</topic><topic>RECTUM</topic><topic>Reproducibility of Results</topic><topic>Sequence analysis</topic><topic>Software</topic><topic>Treatment strategy</topic><topic>VERIFICATION</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Luo, Wei</creatorcontrib><creatorcontrib>Li, Jinsheng</creatorcontrib><creatorcontrib>Price, Robert A.</creatorcontrib><creatorcontrib>Chen, Lili</creatorcontrib><creatorcontrib>Yang, Jie</creatorcontrib><creatorcontrib>Fan, Jiajin</creatorcontrib><creatorcontrib>Chen, Zuoqun</creatorcontrib><creatorcontrib>McNeeley, Shawn</creatorcontrib><creatorcontrib>Xu, Xiu</creatorcontrib><creatorcontrib>Ma, Chang-Ming</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>OSTI.GOV</collection><jtitle>Medical physics (Lancaster)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Luo, Wei</au><au>Li, Jinsheng</au><au>Price, Robert A.</au><au>Chen, Lili</au><au>Yang, Jie</au><au>Fan, Jiajin</au><au>Chen, Zuoqun</au><au>McNeeley, Shawn</au><au>Xu, Xiu</au><au>Ma, Chang-Ming</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Monte Carlo based IMRT dose verification using MLC log files and R/V outputs</atitle><jtitle>Medical physics (Lancaster)</jtitle><addtitle>Med Phys</addtitle><date>2006-07</date><risdate>2006</risdate><volume>33</volume><issue>7</issue><spage>2557</spage><epage>2564</epage><pages>2557-2564</pages><issn>0094-2405</issn><eissn>2473-4209</eissn><coden>MPHYA6</coden><abstract>Conventional IMRT dose verification using film and ion chamber measurements is useful but limited with respect to the actual dose distribution received by the patient. The Monte Carlo simulation has been introduced as an independent dose verification tool for IMRT using the patient CT data and MLC leaf sequence files, which validates the dose calculation accuracy but not the plan delivery accuracy. In this work, we propose a Monte Carlo based IMRT dose verification method that reconstructs the patient dose distribution using the patient CT, actual beam data based on the information from the record and verify system (R/V), and the MLC log files obtained during dose delivery that record the MLC leaf positions and MUs delivered. Comparing the Monte Carlo dose calculation with the original IMRT plan using these data simultaneously validates the accuracy of both the IMRT dose calculation and beam delivery. Such log file based Monte Carlo simulations are expected to be employed as a useful and efficient IMRT QA modality to validate the dose delivered to the patient. We have run Monte Carlo simulations for eight IMRT prostate plans using this method and the results for the target dose were consistent with the original CORVUS treatment plans to within 3.0% and 2.0% with and without heterogeneity corrections in the dose calculation. However, significant dose deviations in nearby critical structures have been observed. The results showed that up to 9.0% of the bladder dose and up to 38.0% of the rectum dose, to which leaf position errors were found to contribute
<
2
%
, were underestimated by the CORVUS treatment planning system. The concept of average leaf position error has been defined to analyze MLC leaf position errors for an IMRT plan. A linear correlation between the target dose error and the average position error has been found based on log file based Monte Carlo simulations, showing that an average position error of
0.2
mm
can result in a target dose error of about 1.0%.</abstract><cop>United States</cop><pub>American Association of Physicists in Medicine</pub><pmid>16898460</pmid><doi>10.1118/1.2208916</doi><tpages>8</tpages></addata></record> |
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| ispartof | Medical physics (Lancaster), 2006-07, Vol.33 (7), p.2557-2564 |
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| source | MEDLINE; Wiley Journals |
| subjects | ACCURACY Anatomy average leaf position error biological organs BLADDER Computer Simulation COMPUTERIZED SIMULATION CORRECTIONS Data Interpretation, Statistical dose verification Dose-Response Relationship, Radiation dosimetry Error analysis ERRORS Humans IMRT quality assurance (QA) Intensity modulated radiation therapy intensity modulation IONIZATION CHAMBERS log file based Monte Carlo simulation Male Medical treatment planning MLC log file MONTE CARLO METHOD Monte Carlo methods Multileaf collimators PATIENTS PROSTATE Prostatic Neoplasms - radiotherapy QUALITY ASSURANCE Quality assurance in radiotherapy RADIATION DOSE DISTRIBUTIONS RADIATION DOSES radiation therapy RADIOLOGY AND NUCLEAR MEDICINE Radiometry - methods RADIOTHERAPY Radiotherapy Dosage Radiotherapy Planning, Computer-Assisted - methods Radiotherapy, Intensity-Modulated - methods Record and verify systems and applications RECTUM Reproducibility of Results Sequence analysis Software Treatment strategy VERIFICATION |
| title | Monte Carlo based IMRT dose verification using MLC log files and R/V outputs |
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