Abstract：
:Highly focused dose distributions for radiosurgery applications are successfully achieved using either multiple static high-energy particle beams or multiple-arc circular x-ray beams from a linac. It has been suggested that conformal x-ray techniques using dynamically shaped beams with a moving radiation source would offer advantages compared to the use of only circular beams. It is also thought that, generally, charged particle beams such as protons offer dose deposition advantages compared to x-ray beams. A comparison of dose distributions was made between a small number of discrete proton beams, multiple-arc circular x-ray beams, and conformal x-ray techniques. Treatment planning of a selection of radiosurgery cases was done for these three techniques. Target volumes ranged from 1.0-25.0 cm3. Dose distributions and dose volume histograms of the target and surrounding normal brain were calculated. The advantages and limitations of each technique were primarily dependent upon the shape and size of the target volume. In general, proton dose distributions were superior to x-ray distributions; both shaped proton and shaped x-ray beams delivered dose distributions which were more conformal than x-ray techniques using circular beams; and the differences between all proton and x-ray distributions were negligible for the smallest target volumes, and greatest for the larger target volumes.
journal_name
Med Physjournal_title
Medical physicsauthors
Serago CF,Thornton AF,Urie MM,Chapman P,Verhey L,Rosenthal SJ,Gall KP,Niemierko Adoi
10.1118/1.597654subject
Has Abstractpub_date
1995-12-01 00:00:00pages
2111-6issue
12eissn
0094-2405issn
2473-4209journal_volume
22pub_type
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