Accelerated Whole Brain Intracranial Vessel Wall Imaging Using Black Blood Fast Spin Echo With Compressed Sensing (CS-SPACE)

MAGMA. 2018 Jun;31(3):457-467. doi: 10.1007/s10334-017-0667-3. Epub 2017 Dec 5.

Abstract

Objective: Develop and optimize an accelerated, high-resolution (0.5 mm isotropic) 3D black blood MRI technique to reduce scan time for whole-brain intracranial vessel wall imaging.

Materials and methods: A 3D accelerated T1-weighted fast-spin-echo prototype sequence using compressed sensing (CS-SPACE) was developed at 3T. Both the acquisition [echo train length (ETL), under-sampling factor] and reconstruction parameters (regularization parameter, number of iterations) were first optimized in 5 healthy volunteers. Ten patients with a variety of intracranial vascular disease presentations (aneurysm, atherosclerosis, dissection, vasculitis) were imaged with SPACE and optimized CS-SPACE, pre and post Gd contrast. Lumen/wall area, wall-to-lumen contrast ratio (CR), enhancement ratio (ER), sharpness, and qualitative scores (1-4) by two radiologists were recorded.

Results: The optimized CS-SPACE protocol has ETL 60, 20% k-space under-sampling, 0.002 regularization factor with 20 iterations. In patient studies, CS-SPACE and conventional SPACE had comparable image scores both pre- (3.35 ± 0.85 vs. 3.54 ± 0.65, p = 0.13) and post-contrast (3.72 ± 0.58 vs. 3.53 ± 0.57, p = 0.15), but the CS-SPACE acquisition was 37% faster (6:48 vs. 10:50). CS-SPACE agreed with SPACE for lumen/wall area, ER measurements and sharpness, but marginally reduced the CR.

Conclusion: In the evaluation of intracranial vascular disease, CS-SPACE provides a substantial reduction in scan time compared to conventional T1-weighted SPACE while maintaining good image quality.

Keywords: 3D black blood SPACE; Aneurysm; Atherosclerosis; Compressed sensing; Intracranial vessel wall MRI.

MeSH terms

  • Adult
  • Aged
  • Algorithms
  • Aneurysm / diagnostic imaging*
  • Atherosclerosis / diagnostic imaging*
  • Brain / blood supply*
  • Brain / diagnostic imaging*
  • Cerebrovascular Circulation*
  • Cerebrovascular Disorders / diagnostic imaging
  • Contrast Media / chemistry*
  • Female
  • Healthy Volunteers
  • Humans
  • Image Processing, Computer-Assisted
  • Imaging, Three-Dimensional
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Models, Statistical
  • Poisson Distribution
  • Reproducibility of Results
  • Signal-To-Noise Ratio

Substances

  • Contrast Media