MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans
Purpose : To quantify the dosimetric consequences of external patient contour distortions produced on low-field and high-field MRIs for external beam radiation of prostate cancer. Methods and Materials : A linearity phantom consisting of a grid filled with contrast material was scanned on a spiral C...
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| Veröffentlicht in: | International journal of radiation oncology, biology, physics biology, physics, 2002-07, Vol.53 (3), p.757-765 |
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| container_title | International journal of radiation oncology, biology, physics |
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| creator | Mah, Dennis Steckner, Michael Hanlon, Alexandra Freedman, Gary Milestone, Bart Mitra, Raj Shukla, Himu Movsas, Benjamin Horwitz, Eric Väisänen, Pasi P Hanks, Gerald E |
| description | Purpose
: To quantify the dosimetric consequences of external patient contour distortions produced on low-field and high-field MRIs for external beam radiation of prostate cancer.
Methods and Materials
: A linearity phantom consisting of a grid filled with contrast material was scanned on a spiral CT, a 0.23 T open MRI, and a 1.5 T closed bore system. Subsequently, 12 patients with prostate cancer were scanned on CT and the open MRI. A gradient distortion correction (GDC) program was used to postprocess the MRI images. Eight of the patients were also scanned on the 1.5 T MRI with integrated GDC correction. All data sets were fused according to their bony landmarks using a chamfer-matching algorithm. The prostate volume was contoured on an MRI image, irrespective of the apparent prostate location in those sets. Thus, the same target volume was planned and used for calculating the anterior-posterior (AP) and lateral separations. The number of monitor units required for treatment using a four-field conformal technique was compared. Because there are also setup variations in patient outer contours, two different CT scans from 20 different patients were fused, and the differences in AP and lateral separations were measured to obtain an estimate of the mean interfractional separation variation.
Results
: All AP separations measured on MRI were statistically indistinguishable from those on CT within the interfractional separation variations. The mean differences between CT and low-field MRI and CT and high-field MRI lateral separations were 1.6 cm and 0.7 cm, respectively, and were statistically significantly different from zero. However, after the GDC was applied to the low-field images, the difference became 0.4 ± 0.4 mm (mean ± standard deviation), which was statistically insignificant from the CT-to-CT variations. The mean variations in the lateral separations from the low-field images with GDC would result in a dosimetric difference of |
| doi_str_mv | 10.1016/S0360-3016(02)02782-7 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_miscellaneous_71810054</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><els_id>S0360301602027827</els_id><sourcerecordid>71810054</sourcerecordid><originalsourceid>FETCH-LOGICAL-c391t-f36bd823b7cd697e3c2465dd6699595e5862b1655fd9800e133eaf000b4e299a3</originalsourceid><addsrcrecordid>eNqFkE1LXDEUhoMoOlp_giUbiy5um49JcuOmiGgVFEFb0FXITU7alPsxJhmh_74ZZ6jLrnJInnPOmwehI0o-U0Lll0fCJWl4LU8IOyVMtaxRW2hGW6UbLsTTNpr9Q_bQfs6_CSGUqvku2qOMSCYZm6Hnu4cbnOOw7G2J03iGIQRwBU8B_0zWRxgL9jGXKa2eM55GXH4lgMbHAcZc72yPF2nKxRbAzo4OEl70dswf0E6wfYbDzXmAflxdfr-4bm7vv91cnN82jmtamsBl51vGO-W81Aq4Y3MpvJdSa6EFiFayjkohgtctIUA5BxvqV7o5MK0tP0Cf1nNripcl5GKGmB30NQNMy2wUbSkhYl5BsQZdjZsTBLNIcbDpj6HErJyaN6dmJcwQZt6cGlX7Pm4WLLsB_HvXRmIFjjeAzc72IVULMb9zXEnRUl25r2sOqo7XCMlkVwU78DFV58ZP8T9R_gJMYJM5</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>71810054</pqid></control><display><type>article</type><title>MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans</title><source>MEDLINE</source><source>Elsevier ScienceDirect Journals</source><creator>Mah, Dennis ; Steckner, Michael ; Hanlon, Alexandra ; Freedman, Gary ; Milestone, Bart ; Mitra, Raj ; Shukla, Himu ; Movsas, Benjamin ; Horwitz, Eric ; Väisänen, Pasi P ; Hanks, Gerald E</creator><creatorcontrib>Mah, Dennis ; Steckner, Michael ; Hanlon, Alexandra ; Freedman, Gary ; Milestone, Bart ; Mitra, Raj ; Shukla, Himu ; Movsas, Benjamin ; Horwitz, Eric ; Väisänen, Pasi P ; Hanks, Gerald E</creatorcontrib><description>Purpose
: To quantify the dosimetric consequences of external patient contour distortions produced on low-field and high-field MRIs for external beam radiation of prostate cancer.
Methods and Materials
: A linearity phantom consisting of a grid filled with contrast material was scanned on a spiral CT, a 0.23 T open MRI, and a 1.5 T closed bore system. Subsequently, 12 patients with prostate cancer were scanned on CT and the open MRI. A gradient distortion correction (GDC) program was used to postprocess the MRI images. Eight of the patients were also scanned on the 1.5 T MRI with integrated GDC correction. All data sets were fused according to their bony landmarks using a chamfer-matching algorithm. The prostate volume was contoured on an MRI image, irrespective of the apparent prostate location in those sets. Thus, the same target volume was planned and used for calculating the anterior-posterior (AP) and lateral separations. The number of monitor units required for treatment using a four-field conformal technique was compared. Because there are also setup variations in patient outer contours, two different CT scans from 20 different patients were fused, and the differences in AP and lateral separations were measured to obtain an estimate of the mean interfractional separation variation.
Results
: All AP separations measured on MRI were statistically indistinguishable from those on CT within the interfractional separation variations. The mean differences between CT and low-field MRI and CT and high-field MRI lateral separations were 1.6 cm and 0.7 cm, respectively, and were statistically significantly different from zero. However, after the GDC was applied to the low-field images, the difference became 0.4 ± 0.4 mm (mean ± standard deviation), which was statistically insignificant from the CT-to-CT variations. The mean variations in the lateral separations from the low-field images with GDC would result in a dosimetric difference of <1%, assuming an equally weighted four-field 18-MV technique for patient separations up to ∼40 cm.
Conclusions
: For patients with lateral separations <40 cm, a homogeneous calculation simulated using a 1.5 T MRI or a 0.23 T MRI with a gradient distortion correction will yield a monitor unit calculation indistinguishable from that generated using CT simulation.</description><identifier>ISSN: 0360-3016</identifier><identifier>EISSN: 1879-355X</identifier><identifier>DOI: 10.1016/S0360-3016(02)02782-7</identifier><identifier>PMID: 12062622</identifier><identifier>CODEN: IOBPD3</identifier><language>eng</language><publisher>New York, NY: Elsevier Inc</publisher><subject>Aged ; Algorithms ; Biological and medical sciences ; Conformal therapy ; Diseases of the urinary system ; Humans ; Magnetic Resonance Imaging - methods ; Male ; Medical sciences ; Middle Aged ; MRI ; Nephrology. Urinary tract diseases ; Phantoms, Imaging ; Physical Phenomena ; Physics ; Prostate - diagnostic imaging ; Prostate - pathology ; Prostate cancer ; Prostatic Neoplasms - diagnostic imaging ; Prostatic Neoplasms - pathology ; Prostatic Neoplasms - radiotherapy ; Radiotherapy Planning, Computer-Assisted - methods ; Radiotherapy, Conformal ; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects) ; Tomography, X-Ray Computed - methods ; Treatment planning ; Tumors of the urinary system ; Urinary tract. Prostate gland</subject><ispartof>International journal of radiation oncology, biology, physics, 2002-07, Vol.53 (3), p.757-765</ispartof><rights>2002 Elsevier Science Inc.</rights><rights>2002 INIST-CNRS</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c391t-f36bd823b7cd697e3c2465dd6699595e5862b1655fd9800e133eaf000b4e299a3</citedby><cites>FETCH-LOGICAL-c391t-f36bd823b7cd697e3c2465dd6699595e5862b1655fd9800e133eaf000b4e299a3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://www.sciencedirect.com/science/article/pii/S0360301602027827$$EHTML$$P50$$Gelsevier$$H</linktohtml><link.rule.ids>314,776,780,3537,27901,27902,65306</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=13765819$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/12062622$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Mah, Dennis</creatorcontrib><creatorcontrib>Steckner, Michael</creatorcontrib><creatorcontrib>Hanlon, Alexandra</creatorcontrib><creatorcontrib>Freedman, Gary</creatorcontrib><creatorcontrib>Milestone, Bart</creatorcontrib><creatorcontrib>Mitra, Raj</creatorcontrib><creatorcontrib>Shukla, Himu</creatorcontrib><creatorcontrib>Movsas, Benjamin</creatorcontrib><creatorcontrib>Horwitz, Eric</creatorcontrib><creatorcontrib>Väisänen, Pasi P</creatorcontrib><creatorcontrib>Hanks, Gerald E</creatorcontrib><title>MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans</title><title>International journal of radiation oncology, biology, physics</title><addtitle>Int J Radiat Oncol Biol Phys</addtitle><description>Purpose
: To quantify the dosimetric consequences of external patient contour distortions produced on low-field and high-field MRIs for external beam radiation of prostate cancer.
Methods and Materials
: A linearity phantom consisting of a grid filled with contrast material was scanned on a spiral CT, a 0.23 T open MRI, and a 1.5 T closed bore system. Subsequently, 12 patients with prostate cancer were scanned on CT and the open MRI. A gradient distortion correction (GDC) program was used to postprocess the MRI images. Eight of the patients were also scanned on the 1.5 T MRI with integrated GDC correction. All data sets were fused according to their bony landmarks using a chamfer-matching algorithm. The prostate volume was contoured on an MRI image, irrespective of the apparent prostate location in those sets. Thus, the same target volume was planned and used for calculating the anterior-posterior (AP) and lateral separations. The number of monitor units required for treatment using a four-field conformal technique was compared. Because there are also setup variations in patient outer contours, two different CT scans from 20 different patients were fused, and the differences in AP and lateral separations were measured to obtain an estimate of the mean interfractional separation variation.
Results
: All AP separations measured on MRI were statistically indistinguishable from those on CT within the interfractional separation variations. The mean differences between CT and low-field MRI and CT and high-field MRI lateral separations were 1.6 cm and 0.7 cm, respectively, and were statistically significantly different from zero. However, after the GDC was applied to the low-field images, the difference became 0.4 ± 0.4 mm (mean ± standard deviation), which was statistically insignificant from the CT-to-CT variations. The mean variations in the lateral separations from the low-field images with GDC would result in a dosimetric difference of <1%, assuming an equally weighted four-field 18-MV technique for patient separations up to ∼40 cm.
Conclusions
: For patients with lateral separations <40 cm, a homogeneous calculation simulated using a 1.5 T MRI or a 0.23 T MRI with a gradient distortion correction will yield a monitor unit calculation indistinguishable from that generated using CT simulation.</description><subject>Aged</subject><subject>Algorithms</subject><subject>Biological and medical sciences</subject><subject>Conformal therapy</subject><subject>Diseases of the urinary system</subject><subject>Humans</subject><subject>Magnetic Resonance Imaging - methods</subject><subject>Male</subject><subject>Medical sciences</subject><subject>Middle Aged</subject><subject>MRI</subject><subject>Nephrology. Urinary tract diseases</subject><subject>Phantoms, Imaging</subject><subject>Physical Phenomena</subject><subject>Physics</subject><subject>Prostate - diagnostic imaging</subject><subject>Prostate - pathology</subject><subject>Prostate cancer</subject><subject>Prostatic Neoplasms - diagnostic imaging</subject><subject>Prostatic Neoplasms - pathology</subject><subject>Prostatic Neoplasms - radiotherapy</subject><subject>Radiotherapy Planning, Computer-Assisted - methods</subject><subject>Radiotherapy, Conformal</subject><subject>Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects)</subject><subject>Tomography, X-Ray Computed - methods</subject><subject>Treatment planning</subject><subject>Tumors of the urinary system</subject><subject>Urinary tract. Prostate gland</subject><issn>0360-3016</issn><issn>1879-355X</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2002</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNqFkE1LXDEUhoMoOlp_giUbiy5um49JcuOmiGgVFEFb0FXITU7alPsxJhmh_74ZZ6jLrnJInnPOmwehI0o-U0Lll0fCJWl4LU8IOyVMtaxRW2hGW6UbLsTTNpr9Q_bQfs6_CSGUqvku2qOMSCYZm6Hnu4cbnOOw7G2J03iGIQRwBU8B_0zWRxgL9jGXKa2eM55GXH4lgMbHAcZc72yPF2nKxRbAzo4OEl70dswf0E6wfYbDzXmAflxdfr-4bm7vv91cnN82jmtamsBl51vGO-W81Aq4Y3MpvJdSa6EFiFayjkohgtctIUA5BxvqV7o5MK0tP0Cf1nNripcl5GKGmB30NQNMy2wUbSkhYl5BsQZdjZsTBLNIcbDpj6HErJyaN6dmJcwQZt6cGlX7Pm4WLLsB_HvXRmIFjjeAzc72IVULMb9zXEnRUl25r2sOqo7XCMlkVwU78DFV58ZP8T9R_gJMYJM5</recordid><startdate>20020701</startdate><enddate>20020701</enddate><creator>Mah, Dennis</creator><creator>Steckner, Michael</creator><creator>Hanlon, Alexandra</creator><creator>Freedman, Gary</creator><creator>Milestone, Bart</creator><creator>Mitra, Raj</creator><creator>Shukla, Himu</creator><creator>Movsas, Benjamin</creator><creator>Horwitz, Eric</creator><creator>Väisänen, Pasi P</creator><creator>Hanks, Gerald E</creator><general>Elsevier Inc</general><general>Elsevier</general><scope>IQODW</scope><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>7X8</scope></search><sort><creationdate>20020701</creationdate><title>MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans</title><author>Mah, Dennis ; Steckner, Michael ; Hanlon, Alexandra ; Freedman, Gary ; Milestone, Bart ; Mitra, Raj ; Shukla, Himu ; Movsas, Benjamin ; Horwitz, Eric ; Väisänen, Pasi P ; Hanks, Gerald E</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c391t-f36bd823b7cd697e3c2465dd6699595e5862b1655fd9800e133eaf000b4e299a3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2002</creationdate><topic>Aged</topic><topic>Algorithms</topic><topic>Biological and medical sciences</topic><topic>Conformal therapy</topic><topic>Diseases of the urinary system</topic><topic>Humans</topic><topic>Magnetic Resonance Imaging - methods</topic><topic>Male</topic><topic>Medical sciences</topic><topic>Middle Aged</topic><topic>MRI</topic><topic>Nephrology. Urinary tract diseases</topic><topic>Phantoms, Imaging</topic><topic>Physical Phenomena</topic><topic>Physics</topic><topic>Prostate - diagnostic imaging</topic><topic>Prostate - pathology</topic><topic>Prostate cancer</topic><topic>Prostatic Neoplasms - diagnostic imaging</topic><topic>Prostatic Neoplasms - pathology</topic><topic>Prostatic Neoplasms - radiotherapy</topic><topic>Radiotherapy Planning, Computer-Assisted - methods</topic><topic>Radiotherapy, Conformal</topic><topic>Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects)</topic><topic>Tomography, X-Ray Computed - methods</topic><topic>Treatment planning</topic><topic>Tumors of the urinary system</topic><topic>Urinary tract. Prostate gland</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Mah, Dennis</creatorcontrib><creatorcontrib>Steckner, Michael</creatorcontrib><creatorcontrib>Hanlon, Alexandra</creatorcontrib><creatorcontrib>Freedman, Gary</creatorcontrib><creatorcontrib>Milestone, Bart</creatorcontrib><creatorcontrib>Mitra, Raj</creatorcontrib><creatorcontrib>Shukla, Himu</creatorcontrib><creatorcontrib>Movsas, Benjamin</creatorcontrib><creatorcontrib>Horwitz, Eric</creatorcontrib><creatorcontrib>Väisänen, Pasi P</creatorcontrib><creatorcontrib>Hanks, Gerald E</creatorcontrib><collection>Pascal-Francis</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>MEDLINE - Academic</collection><jtitle>International journal of radiation oncology, biology, physics</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Mah, Dennis</au><au>Steckner, Michael</au><au>Hanlon, Alexandra</au><au>Freedman, Gary</au><au>Milestone, Bart</au><au>Mitra, Raj</au><au>Shukla, Himu</au><au>Movsas, Benjamin</au><au>Horwitz, Eric</au><au>Väisänen, Pasi P</au><au>Hanks, Gerald E</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans</atitle><jtitle>International journal of radiation oncology, biology, physics</jtitle><addtitle>Int J Radiat Oncol Biol Phys</addtitle><date>2002-07-01</date><risdate>2002</risdate><volume>53</volume><issue>3</issue><spage>757</spage><epage>765</epage><pages>757-765</pages><issn>0360-3016</issn><eissn>1879-355X</eissn><coden>IOBPD3</coden><abstract>Purpose
: To quantify the dosimetric consequences of external patient contour distortions produced on low-field and high-field MRIs for external beam radiation of prostate cancer.
Methods and Materials
: A linearity phantom consisting of a grid filled with contrast material was scanned on a spiral CT, a 0.23 T open MRI, and a 1.5 T closed bore system. Subsequently, 12 patients with prostate cancer were scanned on CT and the open MRI. A gradient distortion correction (GDC) program was used to postprocess the MRI images. Eight of the patients were also scanned on the 1.5 T MRI with integrated GDC correction. All data sets were fused according to their bony landmarks using a chamfer-matching algorithm. The prostate volume was contoured on an MRI image, irrespective of the apparent prostate location in those sets. Thus, the same target volume was planned and used for calculating the anterior-posterior (AP) and lateral separations. The number of monitor units required for treatment using a four-field conformal technique was compared. Because there are also setup variations in patient outer contours, two different CT scans from 20 different patients were fused, and the differences in AP and lateral separations were measured to obtain an estimate of the mean interfractional separation variation.
Results
: All AP separations measured on MRI were statistically indistinguishable from those on CT within the interfractional separation variations. The mean differences between CT and low-field MRI and CT and high-field MRI lateral separations were 1.6 cm and 0.7 cm, respectively, and were statistically significantly different from zero. However, after the GDC was applied to the low-field images, the difference became 0.4 ± 0.4 mm (mean ± standard deviation), which was statistically insignificant from the CT-to-CT variations. The mean variations in the lateral separations from the low-field images with GDC would result in a dosimetric difference of <1%, assuming an equally weighted four-field 18-MV technique for patient separations up to ∼40 cm.
Conclusions
: For patients with lateral separations <40 cm, a homogeneous calculation simulated using a 1.5 T MRI or a 0.23 T MRI with a gradient distortion correction will yield a monitor unit calculation indistinguishable from that generated using CT simulation.</abstract><cop>New York, NY</cop><pub>Elsevier Inc</pub><pmid>12062622</pmid><doi>10.1016/S0360-3016(02)02782-7</doi><tpages>9</tpages></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0360-3016 |
| ispartof | International journal of radiation oncology, biology, physics, 2002-07, Vol.53 (3), p.757-765 |
| issn | 0360-3016 1879-355X |
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| subjects | Aged Algorithms Biological and medical sciences Conformal therapy Diseases of the urinary system Humans Magnetic Resonance Imaging - methods Male Medical sciences Middle Aged MRI Nephrology. Urinary tract diseases Phantoms, Imaging Physical Phenomena Physics Prostate - diagnostic imaging Prostate - pathology Prostate cancer Prostatic Neoplasms - diagnostic imaging Prostatic Neoplasms - pathology Prostatic Neoplasms - radiotherapy Radiotherapy Planning, Computer-Assisted - methods Radiotherapy, Conformal Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects) Tomography, X-Ray Computed - methods Treatment planning Tumors of the urinary system Urinary tract. Prostate gland |
| title | MRI simulation: effect of gradient distortions on three-dimensional prostate cancer plans |
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