A method of correcting dose distributions produced by IMRT planning systems

L. B. Leybovich, Nesrin Dogan, A. Sethi, M. J. Krasin, B. Emami

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

For some complicated cases, the conformality of dose distributions may be improved only with IMRT. Whereas the set treatment goals may be achieved by the inverse treatment planning systems, the dose distributions in the treatment area may not be satisfactory. According to authors' experience, the dose distributions produced by IMRT planning systems (for both tomographic and "step and shoot" methods) demonstrated excessive radiation of posterior neck (in the case of a neck tumor), or high doses to the lungs (in the case of a thoracic spine tumor). Moreover, high dose regions surrounded the spinal cord in both cases. Due to inevitable errors in patient positioning, this may result in overdosage of critical structures. In this work, a method that consists of addition of "pseudo critical structure(s)", that are positioned in areas that require dose reduction, was developed. The shape and size of these "pseudo structure(s)" depend on the position and volume of the areas that need this reduction. The results of our study have demonstrated that the proposed method significantly improved the dose distribution. In the case of a neck tumor, the plans containing "pseudo structure" demonstrated a significant reduction in the dose delivered to the posterior neck (from 90% or 80% to 30%) for both IMRT delivery techniques. For the thoracic spine tumor, the maximum dose to the lung reduced from 59 Gy to 51 Gy (tomographic delivery) and from 61 Gy to 46 Gy ("step and shoot" delivery).

Original languageEnglish (US)
Title of host publicationAnnual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings
EditorsJ.D. Enderle
Pages466-469
Number of pages4
Volume1
StatePublished - 2000
Externally publishedYes
Event22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society - Chicago, IL, United States
Duration: Jul 23 2000Jul 28 2000

Other

Other22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society
CountryUnited States
CityChicago, IL
Period7/23/007/28/00

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Tumors
Planning
Radiation

Keywords

  • Step and shoot method
  • Tomographic IMRT

ASJC Scopus subject areas

  • Bioengineering

Cite this

Leybovich, L. B., Dogan, N., Sethi, A., Krasin, M. J., & Emami, B. (2000). A method of correcting dose distributions produced by IMRT planning systems. In J. D. Enderle (Ed.), Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings (Vol. 1, pp. 466-469)

A method of correcting dose distributions produced by IMRT planning systems. / Leybovich, L. B.; Dogan, Nesrin; Sethi, A.; Krasin, M. J.; Emami, B.

Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. ed. / J.D. Enderle. Vol. 1 2000. p. 466-469.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Leybovich, LB, Dogan, N, Sethi, A, Krasin, MJ & Emami, B 2000, A method of correcting dose distributions produced by IMRT planning systems. in JD Enderle (ed.), Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. vol. 1, pp. 466-469, 22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Chicago, IL, United States, 7/23/00.
Leybovich LB, Dogan N, Sethi A, Krasin MJ, Emami B. A method of correcting dose distributions produced by IMRT planning systems. In Enderle JD, editor, Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. Vol. 1. 2000. p. 466-469
Leybovich, L. B. ; Dogan, Nesrin ; Sethi, A. ; Krasin, M. J. ; Emami, B. / A method of correcting dose distributions produced by IMRT planning systems. Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings. editor / J.D. Enderle. Vol. 1 2000. pp. 466-469
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