Anisotropic Margin Expansions in 6 Anatomic Directions for Oropharyngeal Image Guided Radiation Therapy.
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| Title: | Anisotropic Margin Expansions in 6 Anatomic Directions for Oropharyngeal Image Guided Radiation Therapy. |
|---|---|
| Authors: | Yock, Adam D.1,2, Garden, Adam S.3, Court, Laurence E.1,2, Beadle, Beth M.3, Zhang, Lifei1, Dong, Lei1,2 dong.lei@scrippshealth.org |
| Source: | International Journal of Radiation Oncology, Biology, Physics. Nov2013, Vol. 87 Issue 3, p596-601. 6p. |
| Subjects: | Image-guided radiation therapy, Computed tomography, Oropharynx, Medical radiology, Medical research, Medical imaging systems |
| Abstract: | Purpose: The purpose of this work was to determine the expansions in 6 anatomic directions that produced optimal margins considering nonrigid setup errors and tissue deformation for patients receiving image-guided radiation therapy (IGRT) of the oropharynx. Methods and Materials: For 20 patients who had received IGRT to the head and neck, we deformably registered each patient's daily images acquired with a computed tomography (CT)-on-rails system to his or her planning CT. By use of the resulting vector fields, the positions of volume elements within the clinical target volume (CTV) (target voxels) or within a 1-cm shell surrounding the CTV (normal tissue voxels) on the planning CT were identified on each daily CT. We generated a total of 15,625 margins by dilating the CTV by 1, 2, 3, 4, or 5 mm in the posterior, anterior, lateral, medial, inferior, and superior directions. The optimal margins were those that minimized the relative volume of normal tissue voxels positioned within the margin while satisfying 1 of 4 geometric target coverage criteria and 1 of 3 population criteria. Results: Each pair of geometric target coverage and population criteria resulted in a unique, anisotropic, optimal margin. The optimal margin expansions ranged in magnitude from 1 to 5 mm depending on the anatomic direction of the expansion and on the geometric target coverage and population criteria. Typically, the expansions were largest in the medial direction, were smallest in the lateral direction, and increased with the demand of the criteria. The anisotropic margin resulting from the optimal set of expansions always included less normal tissue than did any isotropic margin that satisfied the same pair of criteria. Conclusions: We demonstrated the potential of anisotropic margins to reduce normal tissue exposure without compromising target coverage in IGRT to the head and neck. [ABSTRACT FROM AUTHOR] |
| Copyright of International Journal of Radiation Oncology, Biology, Physics is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) | |
| Database: | Engineering Source |
| FullText | Text: Availability: 0 |
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| Header | DbId: egs DbLabel: Engineering Source An: 90421562 AccessLevel: 6 PubType: Academic Journal PubTypeId: academicJournal PreciseRelevancyScore: 0 |
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| Items | – Name: Title Label: Title Group: Ti Data: Anisotropic Margin Expansions in 6 Anatomic Directions for Oropharyngeal Image Guided Radiation Therapy. – Name: Author Label: Authors Group: Au Data: <searchLink fieldCode="AR" term="%22Yock%2C+Adam+D%2E%22">Yock, Adam D.</searchLink><relatesTo>1,2</relatesTo><br /><searchLink fieldCode="AR" term="%22Garden%2C+Adam+S%2E%22">Garden, Adam S.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Court%2C+Laurence+E%2E%22">Court, Laurence E.</searchLink><relatesTo>1,2</relatesTo><br /><searchLink fieldCode="AR" term="%22Beadle%2C+Beth+M%2E%22">Beadle, Beth M.</searchLink><relatesTo>3</relatesTo><br /><searchLink fieldCode="AR" term="%22Zhang%2C+Lifei%22">Zhang, Lifei</searchLink><relatesTo>1</relatesTo><br /><searchLink fieldCode="AR" term="%22Dong%2C+Lei%22">Dong, Lei</searchLink><relatesTo>1,2</relatesTo><i> dong.lei@scrippshealth.org</i> – Name: TitleSource Label: Source Group: Src Data: <searchLink fieldCode="JN" term="%22International+Journal+of+Radiation+Oncology%2C+Biology%2C+Physics%22">International Journal of Radiation Oncology, Biology, Physics</searchLink>. Nov2013, Vol. 87 Issue 3, p596-601. 6p. – Name: Subject Label: Subjects Group: Su Data: <searchLink fieldCode="DE" term="%22Image-guided+radiation+therapy%22">Image-guided radiation therapy</searchLink><br /><searchLink fieldCode="DE" term="%22Computed+tomography%22">Computed tomography</searchLink><br /><searchLink fieldCode="DE" term="%22Oropharynx%22">Oropharynx</searchLink><br /><searchLink fieldCode="DE" term="%22Medical+radiology%22">Medical radiology</searchLink><br /><searchLink fieldCode="DE" term="%22Medical+research%22">Medical research</searchLink><br /><searchLink fieldCode="DE" term="%22Medical+imaging+systems%22">Medical imaging systems</searchLink> – Name: Abstract Label: Abstract Group: Ab Data: Purpose: The purpose of this work was to determine the expansions in 6 anatomic directions that produced optimal margins considering nonrigid setup errors and tissue deformation for patients receiving image-guided radiation therapy (IGRT) of the oropharynx. Methods and Materials: For 20 patients who had received IGRT to the head and neck, we deformably registered each patient's daily images acquired with a computed tomography (CT)-on-rails system to his or her planning CT. By use of the resulting vector fields, the positions of volume elements within the clinical target volume (CTV) (target voxels) or within a 1-cm shell surrounding the CTV (normal tissue voxels) on the planning CT were identified on each daily CT. We generated a total of 15,625 margins by dilating the CTV by 1, 2, 3, 4, or 5 mm in the posterior, anterior, lateral, medial, inferior, and superior directions. The optimal margins were those that minimized the relative volume of normal tissue voxels positioned within the margin while satisfying 1 of 4 geometric target coverage criteria and 1 of 3 population criteria. Results: Each pair of geometric target coverage and population criteria resulted in a unique, anisotropic, optimal margin. The optimal margin expansions ranged in magnitude from 1 to 5 mm depending on the anatomic direction of the expansion and on the geometric target coverage and population criteria. Typically, the expansions were largest in the medial direction, were smallest in the lateral direction, and increased with the demand of the criteria. The anisotropic margin resulting from the optimal set of expansions always included less normal tissue than did any isotropic margin that satisfied the same pair of criteria. Conclusions: We demonstrated the potential of anisotropic margins to reduce normal tissue exposure without compromising target coverage in IGRT to the head and neck. [ABSTRACT FROM AUTHOR] – Name: AbstractSuppliedCopyright Label: Group: Ab Data: <i>Copyright of International Journal of Radiation Oncology, Biology, Physics is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.) |
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| RecordInfo | BibRecord: BibEntity: Identifiers: – Type: doi Value: 10.1016/j.ijrobp.2013.06.2036 Languages: – Code: eng Text: English PhysicalDescription: Pagination: PageCount: 6 StartPage: 596 Subjects: – SubjectFull: Image-guided radiation therapy Type: general – SubjectFull: Computed tomography Type: general – SubjectFull: Oropharynx Type: general – SubjectFull: Medical radiology Type: general – SubjectFull: Medical research Type: general – SubjectFull: Medical imaging systems Type: general Titles: – TitleFull: Anisotropic Margin Expansions in 6 Anatomic Directions for Oropharyngeal Image Guided Radiation Therapy. Type: main BibRelationships: HasContributorRelationships: – PersonEntity: Name: NameFull: Yock, Adam D. – PersonEntity: Name: NameFull: Garden, Adam S. – PersonEntity: Name: NameFull: Court, Laurence E. – PersonEntity: Name: NameFull: Beadle, Beth M. – PersonEntity: Name: NameFull: Zhang, Lifei – PersonEntity: Name: NameFull: Dong, Lei IsPartOfRelationships: – BibEntity: Dates: – D: 01 M: 11 Text: Nov2013 Type: published Y: 2013 Identifiers: – Type: issn-print Value: 03603016 Numbering: – Type: volume Value: 87 – Type: issue Value: 3 Titles: – TitleFull: International Journal of Radiation Oncology, Biology, Physics Type: main |
| ResultId | 1 |
