MR Angiography of the Cerebral Perforating Arteries With Magnetization Prepared Anatomical Reference at 7T: Comparison With Time-of-Flight

Purpose: To develop a magnetic resonance imaging (MRI) protocol that visualizes both the perforating arteries and the related anatomy in a single acquisition at 7T. Material and Methods: T-1-weighted magnetization prepared imaging (MPRAGE) was empirically modified for use as angiography method at 7T, The resulting sequence depicts the vasculature simultaneously with the surrounding anatomical structures, and is referred to as magnetization prepared anatomical reference MRA (MPARE-MRA). The method was compared to time-of-flight (TOF) MRA in seven healthy subjects. The conspicuity of the perforating arteries and the contrast between gray and white matter were evaluated both quantitatively by contrast-to-noise (CNR) measurements, an qualitatively by two radiologists who scored the images. Results: The contrast-to-noise ratio (CNR) between blood and background was 28 +/- 9 for MPARE-MRA and 35 +/- 16 for TOF-MRA, indicating good conspicuity of the vessels. CNR values were: internal capsule (IC) vs. caudate head (CH): 4.2 +/- 0.7; IC vs. putamen: 3.5 +/- 0.6; white matter vs. gray matter: 9.7 +/- 2.5. Conclusion: The benefits of ultra-high-field MRI can transform MPRAGE into a new angiography method to image small vessels and associated parenchyma at the same time. This technique can be used to study the correlation between tissue damage and vascular pathology.