Motion monitoring during a course of lung radiotherapy with anchored electromagnetic transponders

• Verfasst von: Schmitt, Daniela [VerfasserIn]
• Verfasst von: Gompelmann, Daniela [VerfasserIn]
• Verfasst von: Herth, Felix [VerfasserIn]
• Titel: Motion monitoring during a course of lung radiotherapy with anchored electromagnetic transponders
• Titelzusatz: quantification of inter- and intrafraction motion and variability of relative transponder positions
• Verf.angabe: Daniela Schmitt, Simeon Nill, Falk Roeder, Daniela Gompelmann, Felix Herth, Uwe Oelfke
• Jahr: 2017
• Umfang: 8 S.
• Fussnoten: First online: 21 July 2017 ; Gesehen am 08.06.2018
• Titel Quelle: Enthalten in: Strahlentherapie und Onkologie
• Ort Quelle: Berlin : Springer Medizin, 1997
• Jahr Quelle: 2017
• Band/Heft Quelle: 193(2017), 10, Seite 840-847
• ISSN Quelle: 1439-099X
• DOI: doi:10.1007/s00066-017-1183-0
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1576181243

Abstract

Purpose: Anchored electromagnetic transponders for tumor motion monitoring during lung radiotherapy were clinically evaluated. First, intrafractional motion patterns were analyzed as well as their interfractional variations. Second, intra- and interfractional changes of the geometric transponder positions were investigated. Materials and methods: Intrafractional motion data from 7 patients with an upper or middle lobe tumor and three implanted transponders each was used to calculate breathing amplitudes, overall motion amount and motion midlines in three mutual perpendicular directions and three-dimensionally (3D) for 162 fractions. For 6 patients intra- and interfractional variations in transponder distances and in the size of the triangle defined by the transponder locations over the treatment course were determined. Results: Mean 3D values of all fractions were up to 4.0, 4.6 and 3.4 mm per patient for amplitude, overall motion amount and midline deviation, respectively. Intrafractional transponder distances varied with standard deviations up to 3.2 mm, while a maximal triangle shrinkage of 36.5% over 39 days was observed. Conclusions: Electromagnetic real-time motion monitoring was feasible for all patients. Detected respiratory motion was on average modest in this small cohort without lower lobe tumors, but changes in motion midline were of the same size as the amplitudes and greater midline motion can be observed in some fractions. Intra- and interfractional variations of the geometric transponder positions can be large, so for reliable motion management correlation between transponder and tumor motion needs to be evaluated per patient. Electronic supplementary material: The online version of this article (doi: 10.1007/s00066-017-1183-0) contains supplementary material, which is available to authorized users.