Abstract
Gating is a relatively new and potentially useful therapeutic addition to external beam radiotherapy applied to regions affected by intra-fraction motion. The impact was of gating on treatment margins, image artifacts, and volume and positional accuracy was investigated by CT imaging of sinusoidally moving spheres. The motion of the spheres simulates target motion. During the CT imaging of dynamically moving spheres, gating reproduced the static volume to within 1%, whereas errors of over 20% were observed where gating was not used. Using a theoretical analysis of margins, gating alone or in combination with an electronic portal imaging device may allow a 2-11 mm reduction in the CTV to PTV margin, and thus less healthy tissue need be irradiated. Gating may allow a reduction of treatment margins, an improvement in image quality, and an improvement in positional and volumetric accuracy of the gross tumor volume.
Original language | English (US) |
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Pages (from-to) | 1-6 |
Number of pages | 6 |
Journal | Australasian Physical and Engineering Sciences in Medicine |
Volume | 25 |
Issue number | 1 |
DOIs | |
State | Published - 2002 |
Keywords
- Image artifacts
- Margins
- Respiratory gating
ASJC Scopus subject areas
- Biophysics
- Biomedical Engineering
- Radiology Nuclear Medicine and imaging
- General Physics and Astronomy