AUTHOR=Zhang Feifei , Ran Yuncai , Zhu Ming , Lei Xiaowen , Niu Junxia , Wang Xiao , Zhang Yong , Li Shujian , Zhu Jinxia , Gao Xuemei , Mossa-Basha Mahmud , Cheng Jingliang , Zhu Chengcheng 

TITLE=The Use of Pointwise Encoding Time Reduction With Radial Acquisition MRA to Assess Middle Cerebral Artery Stenosis Pre- and Post-stent Angioplasty: Comparison With 3D Time-of-Flight MRA and DSA

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2021.739332

DOI=10.3389/fcvm.2021.739332

ISSN=2297-055X

ABSTRACT=<p><bold>Background and Purpose:</bold> 3D pointwise encoding time reduction magnetic resonance angiography (PETRA-MRA) is a promising non-contrast magnetic resonance angiography (MRA) technique for intracranial stenosis assessment but it has not been adequately validated against digital subtraction angiography (DSA) relative to 3D-time-of-flight (3D-TOF) MRA. The aim of this study was to compare PETRA-MRA and 3D-TOF-MRA using DSA as the reference standard for intracranial stenosis assessment before and after angioplasty and stenting in patients with middle cerebral artery (MCA) stenosis.</p><p><bold>Materials and Methods:</bold> Sixty-two patients with MCA stenosis (age 53 ± 12 years, 43 males) underwent MRA and DSA within a week for pre-intervention evaluation and 32 of them had intracranial angioplasty and stenting performed. The MRAs' image quality, flow visualization within the stents, and susceptibility artifact were graded on a 1–4 scale (1 = poor, 4 = excellent) independently by three radiologists. The degree of stenosis was measured by two radiologists independently on DSA and MRAs.</p><p><bold>Results:</bold> There was an excellent inter-observer agreement for stenosis assessment on PETRA-MRA, 3D-TOF-MRA, and DSA (ICCs &gt; 0.90). For pre-intervention evaluation, PETRA-MRA had better image quality than 3D-TOF-MRA (3.87 ± 0.34 vs. 3.38 ± 0.65, <italic>P</italic> &lt; 0.001), and PETRA-MRA had better agreement with DSA for stenosis measurements compared to 3D-TOF-MRA (<italic>r</italic> = 0.96 vs. <italic>r</italic> = 0.85). For post-intervention evaluation, PETRA-MRA had better image quality than 3D-TOF-MRA for in-stent flow visualization and susceptibility artifacts (3.34 ± 0.60 vs. 1.50 ± 0.76, <italic>P</italic> &lt; 0.001; 3.31 ± 0.64 vs. 1.41 ± 0.61, <italic>P</italic> &lt; 0.001, respectively), and better agreement with DSA for stenosis measurements than 3D-TOF-MRA (<italic>r</italic> = 0.90 vs. <italic>r</italic> = 0.26). 3D-TOF-MRA significantly overestimated the stenosis post-stenting compared to DSA (84.9 ± 19.7 vs. 39.3 ± 13.6%, <italic>p</italic> &lt; 0.001) while PETRA-MRA didn't (40.6 ± 13.7 vs. 39.3 ± 13.6%, <italic>p</italic> = 0.18).</p><p><bold>Conclusions:</bold> PETRA-MRA is accurate and reproducible for quantifying MCA stenosis both pre- and post-stenting compared with DSA and performs better than 3D-TOF-MRA.</p>