Improved cerebrospinal fluid suppression for intracranial vessel wall MRI

J Magn Reson Imaging. 2016 Sep;44(3):665-72. doi: 10.1002/jmri.25211. Epub 2016 Mar 7.

Abstract

Purpose: To develop and assess a three-dimensional (3D) high resolution black blood MRI (BBMRI) method for evaluation of intracranial vessels with improved cerebrospinal fluid (CSF) suppression.

Materials and methods: The anti-driven-equilibrium (ADE) pulse was incorporated into a variable flip-angle TSE-based 3D BBMRI to improve CSF suppression. ADE-BBMRI was optimized in 8 participants and compared with BBMRI, with acquired 0.5 mm isotropic resolution and scan time of 5.4 min at 3 Tesla. Contrast-enhanced ADE-BBMRI protocol was implemented in nine patients with intracranial atherosclerosis. Signal and morphological measurements were compared between ADE-BBMRI and BBMRI, as well as pre- and postcontrast ADE-BBMRI. Reliability was assessed by intraclass correlations (ICC).

Results: ADE-BBMRI effectively suppressed the surrounding CSF signal of intracranial vessels, with a 36-44% reduction compared with BBMRI. ADE-BBMRI also reduced the overall wall signal by 8-8.5%, but provided a significant improvement in wall-to-CSF contrast-to-noise ratio over BBMRI (middle cerebral artery, 5.93 ± 0.59 versus 3.95 ± 1.67, P < 0.01; basilar artery, 3.8 ± 1.76 versus 1.34 ± 0.54, P = 0.01, respectively). No differences were noted in morphological measurements between ADE-BBMRI and BBMRI (lumen area, 6.35 ± 2.87 versus 6.32 ± 2.84 mm(2) ; wall area, 1.28 ± 0.52 versus 1.27 ± 0.53 mm(2) ; mean wall thickness, 0.93 ± 0.30 versus 0.93 ± 0.32 mm; maximum wall thickness, 1.27 ± 0.33 versus 1.28 ± 0.36 mm, all P > 0.05). Contrast enhanced ADE-BBMRI improved the plaque delineation by the increased wall signal, wall-to-CSF and wall-to-blood contrast-to-noise ratio. ICC ranged from 0.54 to 0.95.

Conclusion: The 3D ADE-BBMRI provides excellent blood and CSF suppression, and accurate measurements of intracranial vessels at 0.5 mm isotropic resolution in 5 min. Its clinical application may provide insight into stroke risk. J. Magn. Reson. Imaging 2016;44:665-672.

Keywords: 3D; MRI; intracranial; isotropic; vessel wall.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Artifacts*
  • Cerebral Angiography / methods
  • Cerebral Arteries / anatomy & histology
  • Cerebral Arteries / diagnostic imaging*
  • Cerebrospinal Fluid / cytology
  • Cerebrospinal Fluid / diagnostic imaging*
  • Female
  • Humans
  • Image Enhancement / methods*
  • Image Interpretation, Computer-Assisted / methods
  • Imaging, Three-Dimensional / methods
  • Magnetic Resonance Angiography / methods*
  • Male
  • Middle Aged
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Signal Processing, Computer-Assisted
  • Subtraction Technique*