Dosimetric comparison between proton and photon beams in the moving gap region in cranio-spinal irradiation (CSI)

Acta Oncologica
Chee-Wai ChengJeffrey C Buchsbaum

Abstract

To investigate the moving gap region dosimetry in proton beam cranio-spinal irradiation (CSI) to provide optimal dose uniformity across the treatment volume. Proton beams of ranges 11.6 cm and 16 cm are used for the spine and the brain fields, respectively. Beam profiles for a 30 cm snout are first matched at the 50% level (hot match) on the computer. Feathering is simulated by shifting the dose profiles by a known distance two successive times to simulate a 2 × feathering scheme. The process is repeated for 2 mm and 4 mm gaps. Similar procedures are used to determine the dose profiles in the moving gap for a series of gap widths, 0-10 mm, and feathering step sizes, 4-10 mm, for a Varian iX 6MV beam. The proton and photon dose profiles in the moving gap region are compared. The dose profiles in the moving gap exhibit valleys and peaks in both proton and photon beam CSI. The dose in the moving gap for protons is around 100% or higher for 0 mm gap, for both 5 and 10 mm feathering step sizes. When the field gap is comparable or larger than the penumbra, dose minima as low as 66% is obtained. The dosimetric characteristics for 6 MV photon beams can be made similar to those of the protons by appropriately combining gap width and fea...Continue Reading

References

Oct 1, 1994·The British Journal of Radiology·C W ChengD J Chen
Feb 18, 2004·International Journal of Radiation Oncology, Biology, Physics·W H St ClairN J Tarbell
Sep 20, 2005·International Journal of Radiation Oncology, Biology, Physics·Catherine T LeeAlfred R Smith
Oct 1, 2005·Journal of Neuro-oncology·Chantal Kalifa, Jacques Grill
Oct 31, 2007·International Journal of Radiation Oncology, Biology, Physics·Sue S YomShiao Woo
Nov 22, 2007·International Journal of Radiation Oncology, Biology, Physics·David M CochranNancy J Tarbell
Dec 23, 2008·International Journal of Radiation Oncology, Biology, Physics·Andrew WroeAnatoly Rosenfeld
Dec 5, 2009·Seminars in Radiation Oncology·Thomas E MerchantJay S Loeffler
Feb 24, 2010·Medical Physics·Ben ClasieAnatoly Rosenfeld
Sep 25, 2010·Nuclear Technology·Phillip J TaddeiWayne D Newhauser

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Citations

Jul 24, 2014·CNS Oncology·Radhika Sreeraman, Daniel J Indelicato
Jun 22, 2013·Pediatric Blood & Cancer·Geoffrey L RayPeter A S Johnstone
Sep 3, 2016·Radiological Physics and Technology·Haruo YamashitaShigeyuki Murayama
Feb 25, 2014·Health Physics·Priscilla K WalkerPeter A S Johnstone
Jun 29, 2021·Frontiers in Oncology·Dakota HorendeckTakamitsu A Kato

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