User menu

Accès à distance ? S'identifier sur le proxy UCLouvain

Experimental and theoretical dosimetry of a new polymer encapsulated iodine-125 source-SmartSeed : dosimetric impact of fluorescence x rays

Primary tabs

Abboud, Fadi [UCL] Scalliet, Pierre [UCL] Hollows, M. Vynckier, Stefaan [UCL]

Methods: Three dosimetric studies have been performed: The first one used thermoluminescent detectors in a solid water phantom with NIST (National Institute of Standards and Technology, USA) calibrated seeds, and two separate studies were of Monte Carlo photon transport calculations (MCNP5 code). The TG-43U1 protocol was applied to derive dosimetric parameters for clinical applications. Results: The radial dose function g(r) was determined at different distances ranging from 0.5 to 10 cm; and the anisotropy function F(r,theta) at angles ranging from 0 degrees to 350 degrees in 10 degrees increments. Monte Carlo calculations were performed in liquid water to obtain values for Lambda, g(r), F(r,theta), and phi(an)(r) as recommended by the TG-43U1 protocol for use in treatment planning system software. SmartSeed's biocompatible polymer capsule permits fluorescence x rays (3, 5, and 12 keV), generated by lead glass marker, to be present in the emission spectrum, influencing the dose rate constant. The impact on near field dosimetry in water from these x rays was also investigated and reported. The capsule also attenuates iodine-125 energies much less than typical titanium encased sources, resulting in a highly isotropic source. Conclusions: SmartSeed has a dose rate constant of 0.895 +/- 7.3% cGy h(-1) U-1, a radial dose function nearly identical to the IBt-Bebig model I25.S06 seed, and a highly isotropic dose distribution. Fluorescence x rays account for the relatively low value of Lambda, yet their variable contribution to dosimetry arising from seed dimensional uncertainties is estimated to be < 0.2%.

Document type Article de périodique (Journal article) – Article de recherche
Access type Accès restreint
Publication date 2010
Language Anglais
Journal information "Medical Physics" - Vol. 37, no. 5, p. 2054-2062 (2010)
Peer reviewed yes
Publisher American Association of Physicists in Medicine ((United States) New-York)
issn 0094-2405
Publication status Publié
Affiliations UCL - SSS/IREC - Institut de recherche expérimentale et clinique
UCL - SSS/IREC/MIRO - Pôle d'imagerie moléculaire, radiothérapie et oncologie
UCL - (SLuc) Service de radiothérapie oncologique
Keywords brachytherapy ; diagnostic radiography ; dosimetry ; fluorescence ; iodine ; Monte Carlo methods ; phantoms ; thermoluminescent dosimeters ; water
Links
  1. Rivard Mark J., Coursey Bert M., DeWerd Larry A., Hanson William F., Saiful Huq M., Ibbott Geoffrey S., Mitch Michael G., Nath Ravinder, Williamson Jeffrey F., Update of AAPM Task Group No. 43 Report: A revised AAPM protocol for brachytherapy dose calculations, 10.1118/1.1646040
  2. Seltzer S.M., Lamperti P.J., Loevinger R., Mitch M.G., Weaver J.T., Coursey B.M., New national air-kerma-strength standards for I-125 and Pd-103 brachytherapy seeds, 10.6028/jres.108.030
  3. B. J. Mijnheer A. H. L. Aalbers J. J. M. van Gasteren A. G. Visser F. W. Wittkämper Code of practice for the dosimetry of high energy photon beams 1986
  4. Reniers B, Vynckier S, Scalliet P, Dosimetric study of a new palladium seed, 10.1016/s0969-8043(02)00193-8
  5. Meigooni Ali S., Meli Jerome A., Nath Ravinder, A comparison of solid phantoms with water for dosimetry of 1 2 5 I brachytherapy sources : Comparison of solid phantoms with water for dosimetry, 10.1118/1.596182
  6. Abboud F., Scalliet P., Vynckier S., An experimental palladium-103 seed (OptiSeedexp) in a biocompatible polymer without a gold marker: Characterization of dosimetric parameters including the interseed effect : Dosimetric study of experimental seed, 10.1118/1.3006151
  7. Williamson, Phys. Med. Biol., 18, 776 (1991)
  8. ICRU 44 tissue substitutes in radiation dosimetry and measurement, international commission on radiation units and measurements 1989
  9. B. Reniers The use of low energy photons in brachytherapy: Dosimetric and microdosimetric studies around P 103 d and I 125 seeds 2005 63
  10. M. C. White Photoatomic data library MCPLIB04: A new photoatomic library based on data from ENDF/B-VI release 8 2002 http://www-xdiv.lanl.gov/PROJECTS/DATA/nuclear/pdf/mcw-02-111.pdf
  11. D. E. Cullen J. H. Hubbel L. D. Kissel EPDL97: The evaluated photon data library, ’97 version 6 1997
  12. ENDF Cross Section Evaluation Working Group ENDF/B-VI summary documentation (ENDF-201) 2000
  13. J. H. Hubbell J. S. Coursey J. Hwang D. S. Zucker 1998 http://physics.nist.gov/PhysRef-Data/photoncs/html/attencoef.html
  14. DeMarco John J, Wallace Robert E, Boedeker Kirsten, An analysis of MCNP cross-sections and tally methods for low-energy photon emitters, 10.1088/0031-9155/47/8/307
  15. Kubo Hideo, Exposure contribution from Ti K x rays produced in the titanium capsule of the clinical I-125 seed : Exposure contribution from Ti K x rays, 10.1118/1.595776
  16. Meigooni A. S., Sowards K., Soldano M., Dosimetric characteristics of the InterSource103palladium brachytherapy source, 10.1118/1.598991
  17. Valicenti R. K., Kirov A. S., Meigooni A. S., Mishra V., Das R. K., Williamson J. F., Experimental validation of Monte Carlo dose calculations about a high-intensity Ir-192 source for pulsed dose-rate brachytherapy, 10.1118/1.597484
  18. Williamson Jeffrey F., Monte Carlo modeling of the transverse-axis dose distribution of the Model 200 103Pd interstitial brachytherapy source, 10.1118/1.598924
  19. Medich David C., Tries Mark A., Munro John J., Monte Carlo characterization of an ytterbium-169 high dose rate brachytherapy source with analysis of statistical uncertainty : Dosimetric characterization of ytterbium-169 with analysis of uncertainty, 10.1118/1.2147767
  20. ICRU Stopping powers for electrons and positrons 1984
  21. ICRU Stopping power and ranges for protons and alpha particles 1993
  22. Nath Ravinder, Anderson Lowell L., Luxton Gary, Weaver Keith A., Williamson Jeffrey F., Meigooni Ali S., Dosimetry of interstitial brachytherapy sources: Recommendations of the AAPM Radiation Therapy Committee Task Group No. 43, 10.1118/1.597458
  23. ESTAR-Stopping-power and range tables for electrons
  24. Reniers B., Vynckier S., Scalliet P., Dosimetric study of the new InterSource125iodine seed, 10.1118/1.1415072
  25. Hedtjärn Håkan, Carlsson Gudrun Alm, Williamson Jeffrey F., Monte Carlo-aided dosimetry of the symmetra model I25.S06 125I, interstitial brachytherapy seed, 10.1118/1.598990
  26. Taylor R. E. P., Yegin G., Rogers D. W. O., Benchmarking BrachyDose: Voxel based EGSnrc Monte Carlo calculations of TG-43 dosimetry parameters : Benchmarking the EGSnrc user-code BrachyDose, 10.1118/1.2400843
  27. Soares C G, Douysset G, Mitch M G, Primary standards and dosimetry protocols for brachytherapy sources, 10.1088/0026-1394/46/2/s06
Bibliographic reference Abboud, Fadi ; Scalliet, Pierre ; Hollows, M. ; Vynckier, Stefaan. Experimental and theoretical dosimetry of a new polymer encapsulated iodine-125 source-SmartSeed : dosimetric impact of fluorescence x rays. In: Medical Physics, Vol. 37, no. 5, p. 2054-2062 (2010)
Permanent URL http://hdl.handle.net/2078.1/33908