Journal of Medical Physics (Jan 2019)

Evaluation and validation of IBA I'MatriXX array for patient-specific quality assurance of tomotherapy®

  • N V. N Madhusudhana Sresty,
  • A Krishnam Raju,
  • B Nagarjuna Reddy,
  • V C Sahithya,
  • Yakub Mohmd,
  • G Deleep Kumar,
  • T Anil Kumar,
  • Tasneem Rushdi,
  • S Aparna,
  • G Durga Prasad,
  • Harjot Kaur Bajwa

DOI
https://doi.org/10.4103/jmp.JMP_11_19
Journal volume & issue
Vol. 44, no. 3
pp. 222 – 227

Abstract

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TomoTherapy® is a modern radiation treatment technique in which intensity-modulated radiation therapy (IMRT) is delivered in helical fashion. A two-dimensional (2D) array which has been existing for IMRT patient-specific quality assurance (PSQA) verifications for many years is I'MatriXX. Our objectives were to validate this I'MatriXX and to evaluate it for different patient sites and fractionation schedules of TomoTherapy treatment. Twenty-five plans were created with virtual target for different possible pitch values and field widths for validation. Gamma index criteria of 3%/2% dose differences and 3/2 mm distance to agreement were used. QA plans of 26 different treatment sites and different fractionation schedules were used. Results indicated that the matrix response is independent of field width, pitch, and modulation factor of TomoTherapy with 3%, 3 mm criteria. High passing rate ranging from 99.7% to 90.7% was observed for selected patient plans. We found that I'MatriXX 2D array can be utilized for easy and quick TomoTherapy PSQA.

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