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An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging.

Publication ,  Journal Article
Faught, AM; Yin, F-F; Adamson, J
Published in: J Appl Clin Med Phys
January 2017

PURPOSE: TrueBeams equipped with the 40 × 30 cm2 Electronic Portal Imaging Devices (EPIDs) are prone to image saturation at the image center when used with flattening filter free (FFF) photon energies. While cine imaging during treatment may not saturate because the beam is attenuated by the patient, the flood field calibration is affected when the standard calibration procedure is followed. Here, we describe the hardware and protocol to achieve improved image quality for this model of TrueBeam EPID. MATERIALS & METHODS: A stainless steel filter of uniform thickness was designed to have sufficient attenuation to avoid panel saturation. The cine imaging flood field calibration was acquired with the filter in place for the FFF energies under the standard calibration geometry (SID = 150 cm). Image quality during MV cine was assessed with & without the modified flood field calibration using a low contrast resolution phantom and an anthropomorphic phantom. RESULTS: When the flood field is acquired without the filter in place, a pixel gain artifact is clearly present in the image center which may be mis-attributed to panel saturation in the subject image. At the image center, the artifact obscured all low contrast inserts and was also visible on the anthropomorphic phantom. Using the filter for flood field calibration eliminates the artifact. CONCLUSION: TrueBeams equipped with the 40 × 30 cm2 IDU can utilize a modified flood field calibration procedure for FFF photon energies that improves image quality for cine MV imaging.

Duke Scholars

Published In

J Appl Clin Med Phys

DOI

EISSN

1526-9914

Publication Date

January 2017

Volume

18

Issue

1

Start / End Page

265 / 268

Location

United States

Related Subject Headings

  • Radiometry
  • Photons
  • Phantoms, Imaging
  • Pelvis
  • Particle Accelerators
  • Nuclear Medicine & Medical Imaging
  • Image Processing, Computer-Assisted
  • Humans
  • Calibration
  • 5105 Medical and biological physics
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Faught, A. M., Yin, F.-F., & Adamson, J. (2017). An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging. J Appl Clin Med Phys, 18(1), 265–268. https://doi.org/10.1002/acm2.12023
Faught, Austin M., Fang-Fang Yin, and Justus Adamson. “An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging.J Appl Clin Med Phys 18, no. 1 (January 2017): 265–68. https://doi.org/10.1002/acm2.12023.
Faught AM, Yin F-F, Adamson J. An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging. J Appl Clin Med Phys. 2017 Jan;18(1):265–8.
Faught, Austin M., et al. “An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging.J Appl Clin Med Phys, vol. 18, no. 1, Jan. 2017, pp. 265–68. Pubmed, doi:10.1002/acm2.12023.
Faught AM, Yin F-F, Adamson J. An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging. J Appl Clin Med Phys. 2017 Jan;18(1):265–268.

Published In

J Appl Clin Med Phys

DOI

EISSN

1526-9914

Publication Date

January 2017

Volume

18

Issue

1

Start / End Page

265 / 268

Location

United States

Related Subject Headings

  • Radiometry
  • Photons
  • Phantoms, Imaging
  • Pelvis
  • Particle Accelerators
  • Nuclear Medicine & Medical Imaging
  • Image Processing, Computer-Assisted
  • Humans
  • Calibration
  • 5105 Medical and biological physics