AUTHOR=Weiss Karl Jakob , Eggers Holger , Stehning Christian , Kouwenhoven Marc , Nassar Mithal , Pieske Burkert , Stawowy Philipp , Schnackenburg Bernhard , Kelle Sebastian 

TITLE=Feasibility and Robustness of 3T Magnetic Resonance Angiography Using Modified Dixon Fat Suppression in Patients With Known or Suspected Peripheral Artery Disease

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=7

YEAR=2020

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2020.549392

DOI=10.3389/fcvm.2020.549392

ISSN=2297-055X

ABSTRACT=<p><bold>Objective:</bold> Contrast-enhanced magnetic resonance angiography (CE-MRA) is a well-established non-invasive imaging technique for the assessment of peripheral artery disease (PAD). A subtractionless method using modified Dixon (mDixon) fat suppression showed superior image quality at 1.5T over the common subtraction method, using a three-positions stepping table approach with a single dose of contrast agent. The aim of this study was to investigate the feasibility of subtractionless first-pass peripheral MRA at 3T in patients with known or suspected PAD and to compare the performance in terms of vessel-to-background contrast (VBC), signal-to-noise ratio (SNR), and subjective image quality to conventional subtraction MRA.</p><p><bold>Methods:</bold> Ten patients [mean age 69 years ± 12 standard deviation (SD)] with known or suspected PAD were examined on a clinical 3T scanner (Ingenia, Philips Healthcare, Best, Netherlands) at three table positions using subtractionless and subtraction first-pass peripheral MRA. Two readers rated image quality on a four- point scale. Interobserver agreement was expressed in quadratic weighted κ values. VBC was assessed with a semi-automated process and SNR was compared in a healthy volunteer.</p><p><bold>Results:</bold> Subjective image quality was significantly better with the subtractionless method overall (mean image quality for mDixon imaging: 2.88 ± 0.32 SD vs. for subtraction imaging: 2.57 ± 0.48 SD; <italic>P</italic> &lt; 0.001) and per table position (abdominal position: 2.88 ± 0.32 vs. 2.57 ± 0.48 SD; <italic>P</italic> &lt; 0.001); upper leg position: (2.97 ± 0.15 SD vs. 2.68 ± 0.37 SD; <italic>P</italic> &lt; 0.001; lower leg position: 2.60 ± 0.50 SD vs. 2.13 ± 0.60 SD; <italic>P</italic> &lt; 0.001). Vessel-to-background contrast increased by 22% with the subtractionless method overall (mean VBC for mDixon imaging: 23.16 ± 8.4 SD vs. for subtraction imaging: 19.00 ± 8.1 SD; factor 1.22, <italic>P</italic> &lt; 0.001). SNR was 82% higher with the subtractionless method (overall SNR gain 1.82; <italic>P</italic> &lt; 0.001).</p><p><bold>Conclusion:</bold> This study demonstrated the feasibility and robustness of subtractionless first-pass peripheral MRA at 3T in patients with known or suspected PAD using a three- positions stepping table approach with a single dose of contrast agent. It showed increased image quality compared to the conventional subtraction method and superior performance in terms of SNR and vessel-to-background contrast.</p>