TY - JOUR AU - Granero, D. AU - Vijande, J. AU - Ballester, F. AU - Rivard, M. J. PY - 2011 DA - 2011// TI - Dosimetry revisited for the HDR Ir-192 brachytherapy source model mHDR-v2 T2 - Med. Phys. JO - Medical Physics SP - 487 EP - 494 VL - 38 IS - 1 PB - Amer Assoc Physicists Medicine Amer Inst Physics KW - Ir-192 KW - brachytherapy KW - dosimetry KW - TG-43 KW - PSS model KW - MCNP5 KW - PENELOPE2008 KW - GEANT4 AB - Purpose: Recently, the manufacturer of the HDR Ir-192 mHDR-v2 brachytherapy source reported small design changes (referred to herein as mHDR-v2r) that are within the manufacturing tolerances but may alter the existing dosimetric data for this source. This study aimed to (1) check whether these changes affect the existing dosimetric data published for this source; (2) obtain new dosimetric data in close proximity to the source, including the contributions from 192Ir electrons and considering the absence of electronic equilibrium; and (3) obtain scatter dose components for collapsed cone treatment planning system implementation. Methods: Three different Monte Carlo (MC) radiation transport codes were used: MCNP5, PENELOPE2008, and GEANT4. The source was centrally positioned in a 40 cm radius water phantom. Absorbed dose and collision kerma were obtained using 0.1 mm (0.5 mm) thick voxels to provide high-resolution dosimetry near (far from) the source. Dose-rate distributions obtained with the three MC codes were compared. Results: Simulations of mHDR-v2 and mHDR-v2r designs performed with three radiation transport codes showed agreement typically within 0.2% for r >= 0.25 cm. Dosimetric contributions from source electrons were significant for r<0.25 cm. The dose-rate constant and radial dose function were similar to those from previous MC studies of the mHDR-v2 design. The 2D anisotropy function also coincided with that of the mHDR-v2 design for r >= 0.25 cm. Detailed results of dose distributions and scatter components are presented for the modified source design. Conclusions: Comparison of these results to prior MC studies showed agreement typically within 0.5% for r >= 0.25 cm. If dosimetric data for r<0.25 cm are not needed, dosimetric results from the prior MC studies will be adequate. c 2011 American Association of Physicists in Medicine. SN - 0094-2405 UR - https://doi.org/10.1118/1.3531973 DO - 10.1118/1.3531973 LA - English N1 - ISI:000285769800050 ID - Granero_etal2011 ER -