Evaluation of geometrically optimized single- and double-plane interstitial high dose rate implants with respect to conformality and homogeneity

Tibor Major, Csaba Polgár, János Fodor, Zoltán Takácsi-Nagy, László Mangel, György Németh

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The use of a stepping source in high dose rate brachytherapy supported with dwell-time optimization makes it possible to deviate from the classical dosimetry systems. Dose distributions of single- and double-plane implants were analysed for conformality and homogeneity at idealized target volumes. The Paris system was used for catheter positioning and target volume determination. Geometric optimization and individual dose prescription were applied. Volumetric indices and dose parameters were calculated at optimal active length, which was found to be equal to target volume length. The mean conformality, homogeneity, external volume and overdose volume indices were 0.78. 0.67, 0.22 and 0.13, respectively. The average minimum target and reference doses were 69% and 86%, respectively. Comparisons between the volumetric indices of geometrical optimized and non-optimized implants were also performed, and a significant difference was found regarding any index. The geometrical optimization resulted in superior conformality and slightly inferior homogeneity. At geometrically optimized implants, the active length can be reduced compared to non-optimized implants. Volumetric parameters and dose-volume histogram-based individual dose prescription are recommended for quantitative assessment of interstitial implants.

Original languageEnglish
Pages (from-to)15-21
Number of pages7
JournalActa Oncologica
Volume42
Issue number1
DOIs
Publication statusPublished - Mar 22 2003

ASJC Scopus subject areas

  • Hematology
  • Oncology
  • Radiology Nuclear Medicine and imaging

Fingerprint Dive into the research topics of 'Evaluation of geometrically optimized single- and double-plane interstitial high dose rate implants with respect to conformality and homogeneity'. Together they form a unique fingerprint.

  • Cite this