Target motion tracking with a scanned particle beam

Journal Article · Sat Dec 15 04:00:00 EST 2007 · Medical Physics

DOI:https://doi.org/10.1118/1.2815934· OSTI ID:21032882

Bert, Christoph; Saito, Nami; Schmidt, Alexander; Chaudhri, Naved; Schardt, Dieter; Rietzel, Eike ^[1]

---

1. Abteilung Biophysik, Gesellschaft fuer Schwerionenforschung (GSI), Planckstrasse 1, 64291 Darmstadt (Germany)

Treatment of moving targets with scanned particle beams results in local over- and under-dosage due to interplay of beam and target motion. To mitigate the impact of respiratory motion, a motion tracking system has been developed and integrated in the therapy control system at Gesellschaft fuer Schwerionenforschung. The system adapts pencil beam positions as well as the beam energy according to target motion to irradiate the planned position. Motion compensation performance of the tracking system was assessed by measurements with radiographic films and a 3D array of 24 ionization chambers. Measurements were performed for stationary detectors and moving detectors using the tracking system. Film measurements showed comparable homogeneity inside the target area. Relative differences of 3D dose distributions within the target volume were 1{+-}2% with a maximum of 4%. Dose gradients and dose to surrounding areas were in good agreement. The motion tracking system successfully preserved dose distributions delivered to moving targets and maintained target conformity.

• OSTI ID: 21032882
• Journal Information: Medical Physics, Journal Name: Medical Physics Journal Issue: 12 Vol. 34; ISSN 0094-2405; ISSN MPHYA6
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BEAM POSITION
CONTROL SYSTEMS
DOSIMETRY
FILM DOSIMETRY
IONIZATION CHAMBERS
ORGANS
PARTICLE BEAMS
RADIATION DOSE DISTRIBUTIONS
RADIATION DOSES
RADIOTHERAPY