Abstract:
:In proton scanning systems that employ active energy variation for depth modulation, a switch of the particle energy might typically require 1-2 s. For plans comprising many energy slices, these seconds could sum up to a non-negligible fraction of the total treatment duration. We have applied the Nyquist-Shannon sampling theorem to determine an efficient spatial arrangement of Bragg peaks in a target volume. This pre-determined schedule of increasing energy spacing with higher energy allows us to reduce the number of used energy slices without compromising the physical dosimetric quality of a plan. Our results suggest that the advantage of such a simple implementation would be especially significant for larger, deep-seated tumors such as the prostate; the number of energy slices was cut by a factor of 2-6.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Kang JH,Wilkens JJ,Oelfke Udoi
10.1088/0031-9155/53/9/N01subject
Has Abstractpub_date
2008-05-07 00:00:00pages
N149-55issue
9eissn
0031-9155issn
1361-6560pii
S0031-9155(08)71666-Xjournal_volume
53pub_type
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