Intravascular brachytherapy: Gamma verses beta sources and centering in endovascular brachytherapy Conference Paper

  


Author: Amols, H. I.
Editors: Kappas, C.; DelGuerra, A.; Kolitsi, Z.; Damilakis, Y.; Theodorou, K.
Title: Intravascular brachytherapy: Gamma verses beta sources and centering in endovascular brachytherapy
Conference Title: 6th International Conference on Medical Physics
Abstract: Intravascular Brachytherapy (IVB) can reduce restenosis and improve the outcome of coronary angioplasty. The dosimetric requirements for IVB include delivering 8-40 Gy to a 2-5 cm length of arterial wall, typically 2-4 mm diameter; minimizing dose to normal tissues and staff; clinical dose rate >2 Gy/min; and source design compatible with cardiac catheters. These requirements are best met by a gamma source with energy <100 keV and activity >1 Ci. Beta sources >3MeV energy and activity >20mCi may provide another alternative. No ideal sources currently exist, and all clinical trials utilize alternative sources such as Ir-192 p(32) Sr-90, Y-90, W-188, or Re-188. Ir-192 provides the best dose distribution but presents safely concerns. Betas simplify radiation safety, but may not provide adequate depth dose. This defines the "gamma vs, beta debate". The search for the "ideal isotope" continues as well as development of new dose delivery systems. New questions specific to IVB must be addressed by the medical physicist: Assess the multitude of radiation systems (catheter based seeds and wires, stents, balloons, gamma vs. beta isotopes, etc.) Determine dose at distances less than or equal to 2 mm from a brachytherapy source. Utilize information from Intravascular Ultrasound (IVUS) and Angiography for treatment planning.
Keywords: radiation; dosimetry; stent; therapy; catheter; neointimal hyperplasia
Journal Title Patras Medical Physics 99
Conference Dates: 1999 Sep 1-4
Conference Location: Patras, Greece
ISBN: 9788832309010
Publisher: Monduzzi Editore  
Location: Bologna, Italy
Date Published: 1999-01-01
Start Page: 57
End Page: 63
Language: English
ACCESSION: WOS:000088407900008
PROVIDER: wos
Notes: Proceedings Paper -- VIth International Conference on Medical Physics -- SEP 01-04, 1999 -- PATRAS, GREECE -- Source: Wos