## Resumen

Purpose: Regularization techniques for determining the optimal dose distribution have been proposed because the dose distributions produced by different IMRT treatment planning optimization algorithms are highly non‐uniform in the target volume. In the present work, an analysis is made about the relation of the DVH gradient and the dose to the PTV and normal tissues. Method and Materials: In this study, two head & neck and prostate cancer cases treated with IMRT were employed. Three different dose distributions were obtained by using a dose‐based optimization technique, an EUD‐based optimization without regularization of non‐uniformity and an EUD‐based optimization using a variational regularization technique. The clinical effectiveness of the three dose distributions was investigated by using the complication‐free tumor control probability, P_{+} and the biologically effective uniform dose. Results: In the head & neck case, for the dose‐based optimization, the P_{+} value is 32.9%, the total control probability P_{B} is 79.6% and the total complication probability P_{I} is 49.0%. For the EUD‐based no‐reg optimization, the P_{+} value is 56.4%, the P_{B} value is 71.9% and the P_{I} value is 15.5%. For the EUD‐based reg optimization, the P_{+} value is 67.3%, the P_{B} value is 87.4% and the P_{I} value is 20.1%. In the prostate case, for the dose‐based optimization, the P_{+} value is 94.8%, the P_{B} value is 97.8% and the P_{I} value is 3.0%. For the EUD‐based no‐reg optimization, the P_{+} value is 86.0%, the P_{B} value is 97.3% and the P_{I} value is 11.3%. For the EUD‐based reg optimization, the P_{+} value is 95.3%, the P_{B} value is 98.4% and the P_{I} value is 3.1%. Conclusion: The radiobiological comparison shows that the EUD‐based optimization with regularization gives better results than the EUD‐based optimization without regularization and dose‐based optimization in both clinical cases, which indicates better clinical effectiveness.

Idioma original | English (US) |
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Páginas (desde-hasta) | 2820 |

Número de páginas | 1 |

Publicación | Medical physics |

Volumen | 35 |

N.º | 6 |

DOI | |

Estado | Published - jun 2008 |

## ASJC Scopus subject areas

- Biophysics
- Radiology Nuclear Medicine and imaging