Comparison of different 3.0 T MR sequences for lumbosacral plexus and its branches: Preliminary study

Abstract

Abstract

Purpose: The purpose of this study is to prospectively evaluate four MR sequences (Proset, FLAIR, B-TFE, T2 Drive) for lumbosacral plexus and its branches

Materials and Methods: Ten healthy young volunteers (M:F = 8:2 Mean age = 31.6 years; range 27~39 years) underwent all four sequences of MRI on lumbosacral area : Proset, FLAIR, B-TFE and T2 Drive. Coronal and both oblique plane reconstruction images are obtained in each sequences. Two radiologists evaluated and scored each MR sequences in consensus. General image quality was scored from 1 (poor) to 5 (excellent). The numbers of visualized bilateral spinal nerves from L2 to S1 was counted (ten in total) The overlapping vessels obscuring plexus were evaluated semiquatitatively (1= many, 2=some, 3=few) Image quality defining spinal nerves and its branches (common peroneal nerve,tibial nerve, sciatic nerve, femoral nerve and obturator nerve) were also scored (0=nonvisualized, 1 = poor, 2 = moderate, 3 = good). For statistical analysis, Friedmann test and Wilcoxon signed rank test was done.

Results: In general image quality part, Proset (mean = 4.2, range 3~5) and B-TFE (mean = 3.7 range 3~5) got the highest scores. The number of visualized spinal nerves were most on Proset image (mean = 9.2, range 8~10). Discrimination between the nerves and the vessels were best on both FLAIR(mean = 2.1, range 1~3) and T2 Drive images(mean = 2.1, range 1~3). Sciatic nerve, common peroneal nerve, and tibial nerve were well visualized on both Proset(mean = 2.9, range 2~3) and FLAIR images (mean = 2.6, range 1~3) without significant statistical difference. Femoral nerve was best seen on FLAIR image(mean = 2.7, range 1~3). Obturator nerve was significantly well-visualized on only Proset image(mean = 2.6, range 1~3).

Conclusion: Proset is the best sequence in general evaluation of the lumbosacral plexus and its major branches. FLAIR sequence can be a complementary sequence for evaluation of nerves overlapping vascular and muscular structures.