Improving quality of arterial spin labeling MR imaging at 3 Tesla with a 32-channel coil and parallel imaging

J Magn Reson Imaging. 2012 May;35(5):1233-9. doi: 10.1002/jmri.23586. Epub 2012 Jan 13.

Abstract

Purpose: To compare 12-channel and 32-channel phased-array coils and to determine the optimal parallel imaging (PI) technique and factor for brain perfusion imaging using Pulsed Arterial Spin labeling (PASL) at 3 Tesla (T).

Materials and methods: Twenty-seven healthy volunteers underwent 10 different PASL perfusion PICORE Q2TIPS scans at 3T using 12-channel and 32-channel coils without PI and with GRAPPA or mSENSE using factor 2. PI with factor 3 and 4 were used only with the 32-channel coil. Visual quality was assessed using four parameters. Quantitative analyses were performed using temporal noise, contrast-to-noise and signal-to-noise ratios (CNR, SNR).

Results: Compared with 12-channel acquisition, the scores for 32-channel acquisition were significantly higher for overall visual quality, lower for noise and higher for SNR and CNR. With the 32-channel coil, artifact compromise achieved the best score with PI factor 2. Noise increased, SNR and CNR decreased with PI factor. However mSENSE 2 scores were not always significantly different from acquisition without PI.

Conclusion: For PASL at 3T, the 32-channel coil at 3T provided better quality than the 12-channel coil. With the 32-channel coil, mSENSE 2 seemed to offer the best compromise for decreasing artifacts without significantly reducing SNR, CNR.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Algorithms
  • Analysis of Variance
  • Artifacts
  • Brain Mapping / methods*
  • Female
  • Humans
  • Image Enhancement / methods*
  • Image Processing, Computer-Assisted / methods
  • Imaging, Three-Dimensional / methods
  • Magnetic Resonance Imaging / instrumentation
  • Magnetic Resonance Imaging / methods*
  • Male
  • Quality Improvement*
  • Signal-To-Noise Ratio
  • Spin Labels*

Substances

  • Spin Labels