Opto-electronic sensing of body surface topology changes during radiotherapy for rectal cancer.

2.50
Hdl Handle:
http://hdl.handle.net/10541/78896
Title:
Opto-electronic sensing of body surface topology changes during radiotherapy for rectal cancer.
Authors:
Moore, Christopher J; Lilley, Francis; Sauret, Veronique; Lalor, Michael; Burton, David R
Abstract:
PURPOSE: The CT body surface underpins millimeter scale dose computation in radical radiotherapy. A lack of technology has prevented measurement of surface topology changes during irradiation. Consequently, body changes are incorporated into plans statistically. We describe the technology for dynamic measurement of continuous surface topology at submillimeter resolution and suggest appropriately modified planning. MATERIALS AND METHODS: An interferometer casts cosinusoidal fringes across the surface of a patient on a treatment couch. Motion-induced changes to the spatial phase of the fringes are used to generate dynamic sequences of body height maps. Volume-conserving CT warping, guided by height change, is used to illustrate potential planning perturbations. RESULTS: We present the results for a prone patient with rectal carcinoma. At most of the simultaneously measured 440 x 440 points in each of the 898 body height maps in a dynamic sequence, the standard deviations were <1-2 mm, with occasional points of 6 mm. Surface motion predominantly occurred along the small of the back. This motion was periodic and could take the spine and bladder across the 95% isodose contour. CONCLUSIONS: Surface changes are most likely to be within 3 mm during irradiation, despite the effects of breathing and the discomfort of lying prone. The dosimetric effects are acceptable.
Affiliation:
North Western Medical Physics, Christie Hospital NHS Trust, Manchester, United Kingdom. chris.moore@physics.cr.man.ac.uk
Citation:
Opto-electronic sensing of body surface topology changes during radiotherapy for rectal cancer. 2003, 56 (1):248-58 Int. J. Radiat. Oncol. Biol. Phys.
Journal:
International Journal of Radiation Oncology, Biology, Physics
Issue Date:
1-May-2003
URI:
http://hdl.handle.net/10541/78896
DOI:
10.1016/S0360-3016(03)00079-8
PubMed ID:
12694846
Type:
Article
Language:
en
ISSN:
0360-3016
Appears in Collections:
All Christie Publications

Full metadata record

DC FieldValue Language
dc.contributor.authorMoore, Christopher J-
dc.contributor.authorLilley, Francis-
dc.contributor.authorSauret, Veronique-
dc.contributor.authorLalor, Michael-
dc.contributor.authorBurton, David R-
dc.date.accessioned2009-08-27T13:47:32Z-
dc.date.available2009-08-27T13:47:32Z-
dc.date.issued2003-05-01-
dc.identifier.citationOpto-electronic sensing of body surface topology changes during radiotherapy for rectal cancer. 2003, 56 (1):248-58 Int. J. Radiat. Oncol. Biol. Phys.en
dc.identifier.issn0360-3016-
dc.identifier.pmid12694846-
dc.identifier.doi10.1016/S0360-3016(03)00079-8-
dc.identifier.urihttp://hdl.handle.net/10541/78896-
dc.description.abstractPURPOSE: The CT body surface underpins millimeter scale dose computation in radical radiotherapy. A lack of technology has prevented measurement of surface topology changes during irradiation. Consequently, body changes are incorporated into plans statistically. We describe the technology for dynamic measurement of continuous surface topology at submillimeter resolution and suggest appropriately modified planning. MATERIALS AND METHODS: An interferometer casts cosinusoidal fringes across the surface of a patient on a treatment couch. Motion-induced changes to the spatial phase of the fringes are used to generate dynamic sequences of body height maps. Volume-conserving CT warping, guided by height change, is used to illustrate potential planning perturbations. RESULTS: We present the results for a prone patient with rectal carcinoma. At most of the simultaneously measured 440 x 440 points in each of the 898 body height maps in a dynamic sequence, the standard deviations were <1-2 mm, with occasional points of 6 mm. Surface motion predominantly occurred along the small of the back. This motion was periodic and could take the spine and bladder across the 95% isodose contour. CONCLUSIONS: Surface changes are most likely to be within 3 mm during irradiation, despite the effects of breathing and the discomfort of lying prone. The dosimetric effects are acceptable.en
dc.language.isoenen
dc.subjectRectal Canceren
dc.subject.meshAlgorithms-
dc.subject.meshAnthropometry-
dc.subject.meshBody Surface Potential Mapping-
dc.subject.meshCalibration-
dc.subject.meshCarcinoma-
dc.subject.meshHumans-
dc.subject.meshImage Processing, Computer-Assisted-
dc.subject.meshInterferometry-
dc.subject.meshLasers-
dc.subject.meshMotion-
dc.subject.meshMovement-
dc.subject.meshProne Position-
dc.subject.meshRadiotherapy Planning, Computer-Assisted-
dc.subject.meshRectal Neoplasms-
dc.subject.meshReproducibility of Results-
dc.subject.meshRespiration-
dc.subject.meshSubtraction Technique-
dc.subject.meshTomography, X-Ray Computed-
dc.titleOpto-electronic sensing of body surface topology changes during radiotherapy for rectal cancer.en
dc.typeArticleen
dc.contributor.departmentNorth Western Medical Physics, Christie Hospital NHS Trust, Manchester, United Kingdom. chris.moore@physics.cr.man.ac.uken
dc.identifier.journalInternational Journal of Radiation Oncology, Biology, Physicsen

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