A technique for the quantitative evaluation of dose distributions.

@article{Low1998ATF,
  title={A technique for the quantitative evaluation of dose distributions.},
  author={Daniel A. Low and William B. Harms and Sasa Mutic and J. Purdy},
  journal={Medical physics},
  year={1998},
  volume={25 5},
  pages={
          656-61
        }
}
The commissioning of a three-dimensional treatment planning system requires comparisons of measured and calculated dose distributions. Techniques have been developed to facilitate quantitative comparisons, including superimposed isodoses, dose-difference, and distance-to-agreement (DTA) distributions. The criterion for acceptable calculation performance is generally defined as a tolerance of the dose and DTA in regions of low and high dose gradients, respectively. The dose difference and DTA… 

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References

SHOWING 1-8 OF 8 REFERENCES

A software tool for the quantitative evaluation of 3D dose calculation algorithms.

The composite evaluation provides a method for the physicist to efficiently identify regions that fail both the dose-difference and DTA acceptance criteria, and provides a computer platform for the quantitative comparison of calculated and measured dose distributions.

Systematic verification of a three-dimensional electron beam dose calculation algorithm.

The algorithm's ability to accurately simulate commonly used clinical setup geometries, including standard or extended SSDs, blocked fields, irregular surfaces, and heterogeneities, is demonstrated and Regions of disagreement between calculations and measurements are shown.

Verification data for electron beam dose algorithms.

A set of 14 experiments that measured dose distributions for 28 unique beam-phantom configurations that simulated various patient anatomic structures and beam geometries and can be used for verification of electron beam dose algorithms are performed.

Commissioning and quality assurance of treatment planning computers.

Dosimetric evaluation of a pencil-beam algorithm for electrons employing a two-dimensional heterogeneity correction.

Experimental evaluation of a 2D and 3D electron pencil beam algorithm

The authors report on the nature of this 3D implementation and assess the magnitude of discrepancies between calculation and measurement for 10 MeV and 18 MeV electron beams, and for the variety of phantom compositions and geometries identified above.

Three-Dimensional Photon Beam Treatment Planning

Treatment planning is often considered to be the act of entering the patient shape and beam locations into a computer system, and then generating a calculated dose distribution which predicts what one expects the actual dose distribution to be if the patient is treated with the chosen plan.