Comparison of Different 3.0 T Magnetic Resonance Sequences for Lumbosacral Plexus and Its Branches: Preliminary Study

To prospectively evaluate four magnetic resonance sequences [ProSet, fluid attenuation inversion recovery (FLAIR), balanced turbo field echo (B-TFE), T2 Drive] for the lumbosacral plexus and its branches. Ten healthy volunteers who underwent four MRI sequences on lumbosacral area were evaluated for image quality (1 to 5; 1 = poor, 5 = excellent), the number of visualized bilateral spinal nerves from L2 to S1, the overlapping vessels obscuring the plexus (1 = many, 2 = some, 3 = few), and image quality defining spinal nerves (0 = nonvisualized, 1 = poor, 2 = moderate, 3 = good). The ProSet (mean = 4.2, range 3-5) and B-TFE (mean = 3.7, range 3-5) showed better image quality than others. The number of visualized spinal nerves was the largest on ProSet image (mean = 9.2, range 8-10). FLAIR (mean = 2.1, range 1-3) and T2 Drive sequences (mean = 2.1, range 1-3) discriminated the nerves well from the vessels. The main branches of the lumbosacral plexus were well visualized on both ProSet (mean = 2.9, range 2-3) and FLAIR images (mean = 2.6, range 1-3). All of these were statistically significant. ProSet is the best sequence in the evaluation of the lumbosacral plexus and its major branches while FLAIR can be a complementary sequence for the evaluation of nerves overlapping vascular structures.