Comparison of 1.5 and 3.0 T for Contrast-Enhanced Pulmonary Magnetic Resonance Angiography

作者：Londy Frank Joseph^*; Lowe Suzan; Stein Paul D; Weg John G; Eisner Robert L; Leeper Kenneth V; Woodard Pamela K; Sostman H Dirk; Jablonski Kathleen A; Fowler Sarah E; Hales Charles A; Hull Russell D; Gottschalk Alexander; Naidich David P; Chenevert Thomas L

来源：Clinical and Applied Thrombosis/Hemostasis, 2012, 18(2): 134-139.

DOI：10.1177/1076029611419840

• pulmonary embolism
• MRI
• field strength
• image quality

Objective: In a recent multi-center trial of gadolinium contrast-enhanced magnetic resonance angiography (Gd-MRA) for diagnosis of acute pulmonary embolism (PE), two centers utilized a common MRI platform though at different field strengths (1.5T and 3T) and realized a signal-to-noise gain with the 3T platform. This retrospective analysis investigates this gain in signal-to-noise of pulmonary vascular targets. Methods: Thirty consecutive pulmonary MRA examinations acquired on a 1.5T system at one institution were compared to 30 consecutive pulmonary MRA examinations acquired on a 3T system at a different institution. Both systems were from the same MRI manufacturer and both used the same Gd-MRA pulse sequence, although there were some protocol adjustments made due to field strength differences. Region-of-interests were manually defined on the main pulmonary artery, 4 pulmonary veins, thoracic aorta, and background lung for objective measurement of signal-to-noise, contrast-to-noise, and bolus timing bias between centers. Results: The 3T pulmonary MRA protocol achieved higher spatial resolution yet maintained significantly higher signal-to-noise ratio (%26gt;= 13%, p = 0.03) in the main pulmonary vessels relative to 1.5T. There was no evidence of operator bias in bolus timing or patient hemodynamic differences between groups. Conclusion: Relative to 1.5T, higher spatial resolution Gd-MRA can be achieved at 3T with a sustained or greater signal-to-noise ratio of enhanced vasculature.

• 出版日期2012-4