Construction of super-rapid brain MRA using oblique transverse acquisition phase contrast angiography with tilted optimized non-saturated excitation pulse

Magn Reson Imaging. 2022 Jan:85:193-201. doi: 10.1016/j.mri.2021.10.037. Epub 2021 Oct 27.

Abstract

[Background] Magnetic resonance angiography (MRA) is one of the most important sequences to estimate a cerebrovascular disease. We often encounter poor image quality due to slow arterial flow related to aging and motion artifact caused by disturbance of consciousness. We focused on phase contrast angiography (PCA) to overcome these difficulties. PCA can reduce scan time drastically by combining transverse acquisition and partial slab setting covering entire brain arteries. However, transverse acquisition in PCA has a large difference in signal intensity between proximal and distal vessels. Therefore, we apply tilted optimized non-saturated excitation (TONE) to improve image quality. [Purpose] The purpose of this study to investigate the usefulness of TONE for PCA. [Method] We estimated the efficacy of TONE in transverse acquisition PCA using measurement of signal intensity in arteries. We compared image quality among 1 min PCA with/without TONE and time-of flight (TOF)-MRA, by visual. [Result] TONE improved the signal inhomogeneity in entire brain arteries. PCA with TONE (5°-9°) demonstrated the highest image quality. [Conclusion] Oblique transverse acquisition PCA with TONE provides superior image quality compared with TOF with similar scan time. TONE improved image quality by the homogenizing signal intensity of vessels from proximal to distal in oblique transvers acquisition PCA. Our MRA can be performed in about 1 min and provides sufficient quality to estimate brain vessels.

Keywords: MRA; PCA; Stroke; TOF; TONE.

MeSH terms

  • Arteries
  • Artifacts
  • Brain / diagnostic imaging
  • Cerebrovascular Disorders*
  • Humans
  • Magnetic Resonance Angiography* / methods