Dosimetric comparison of two 90Sr/90Y sources for intravascular brachytherapy: an EGSnrc Monte Carlo calculation.
A new 90Sr/90Y catheter-based system, the Beta-Cath 3.5F system, was recently introduced into the clinic for intravascular brachytherapy. This new system has a smaller diameter of delivery catheter (3.5 French) compared to the original Beta-Cath system (5 French catheter). The new source/seed (3.5F source) has a different design from the original (5F) source. In this paper, we report the EGSnrc Monte Carlo results of two-dimensional dose rate distributions in water as well as the TG-60 dose parameters for the new 3.5F source and the original 5F source. A complete set of the dosimetric data for each individual seed is tabulated. A detailed dosimetric comparison was carried out for the two sources. The comparison shows that differences between the two sources are less than 5% in the region of interest for intravascular brachytherapy. Higher differences (up to 10%) are seen in the near-source region, which is mainly inside the delivery catheter. Based on the present calculation and comparison, we conclude that the new Beta-Cath 3.5F system is dosimetrically equivalent to the original Beta-Cath (5F) system. Therefore, clinical dosimetry and the practice of using both the systems can be treated similarly.
Wang
Ruqing
R
Department of Radiation Oncology, University of Maryland, Baltimore, MD 21201, USA. rwang@phys.ualberta.ca
Li
X Allen
XA
D016880:Anisotropy; D001918:Brachytherapy / Q000379:methods*; D009010:Monte Carlo Method; D011874:Radiometry / Q000379:methods*; D011880:Radiotherapy Planning, Computer-Assisted; D012984:Software; D013326:Strontium Radioisotopes / Q000627:therapeutic use*; D015021:Yttrium Radioisotopes / Q000627:therapeutic use*
D013326:Strontium Radioisotopes; D015021:Yttrium Radioisotopes