On replacing the manual measurement of ACR phantom images performed by MRI technologists with an automated measurement approach

J Magn Reson Imaging. 2016 Apr;43(4):843-52. doi: 10.1002/jmri.25052. Epub 2015 Sep 23.

Abstract

Purpose: To assess whether measurements on American College of Radiology (ACR) phantom images performed by magnetic resonance imaging (MRI) technologists as part of a weekly quality control (QC) program could be performed exclusively using an automated system without compromising the integrity of the QC program.

Materials and methods: ACR phantom images are acquired on 15 MRI scanners at a number of ACR-accredited sites to fulfill requirements of a weekly QC program. MRI technologists routinely perform several measurements on these images. Software routines are also used to perform the measurements. A set of geometry measurements made by technologists over a five week period and those made using software routines were compared to reference-standard measurements made by two MRI physicists.

Results: The geometry measurements performed by software routines had a very high positive correlation (0.92) with the reference-standard measurements. Technologist measurements also had a high positive correlation (0.63), although the correlation was less than for the automated measurements. Bland-Altman analysis revealed overall good agreement between the automated and reference-standard measurements, with the 95% limits of agreement being within ±0.62 mm. Agreement between the technologist and the reference-standard measurements was demonstratively poorer, with 95% limits of agreement being ±1.46 mm. Some of the technologist measurements differed from the reference standard by as much as 2 mm.

Conclusion: The technologists' geometry measurements may be able to be replaced by automated measurement without compromising the weekly QC program required by the ACR.

Keywords: ACR phantom imaging; accreditation; quality assurance; quality control.

MeSH terms

  • Humans
  • Image Processing, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Observer Variation
  • Pattern Recognition, Automated*
  • Phantoms, Imaging*
  • Quality Control
  • Radiology / methods*
  • Radiology / standards*
  • Reference Values
  • Signal-To-Noise Ratio
  • Software