MR imaging of the brachial plexus: comparison between 1.5-T and 3-T MR imaging: preliminary experience.
OBJECTIVE
To compare 1.5-T and 3-T magnetic resonance (MR) imaging of the brachial plexus.


METHODS
Institutional review board approval and informed consent were obtained from 30 healthy volunteers and 30 consecutive patients with brachial plexus disturbances. MR was prospectively performed with comparable sequence parameters and coils with a 1.5-T and a 3-T system. Imaging protocols at both field strengths included T1-weighted turbo spin-echo (tSE) sequences and T2-weighed turbo spin-echo (tSE) sequences with fat saturation. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) between muscle and nerve were calculated for both field strengths. The visibility of brachial plexus nerve at various anatomic levels (roots, interscalene area, costoclavicular space, and axillary level) was analyzed with a four-point grading scale by two radiologists. MR imaging diagnoses and pathological findings were also compared qualitatively.


RESULTS
SNR and CNRs were significantly higher on 3-T MR images than on 1.5-T MR images (Friedman test) for all sequences. Nerve visibility was significantly better on 3-T MR images than on 1.5-T MR images (paired sign test). Pathological findings (n = 30/30) were seen equally well with both field strengths. MR imaging diagnoses did not differ for the 1.5- and 3-T protocols.


CONCLUSIONS
High-quality MR images of the brachial plexus can be obtained with 3-T MR imaging by using sequences similar to those used at 1.5-T MR imaging. In patients and healthy volunteers, the visibility of nerve trunks and cords at 3-T MR imaging appears to be superior to that at 1.5-T MR imaging.
Department of Radiology, National Institute for Cancer Research, Genova, Italy. atagliafico@sirm.org
Alberto
A
Tagliafico
Giulia
G
Succio
Carlo
C
Emanuele Neumaier
Giovanni
G
Serafini
Matteo
M
Ghidara
Massimo
M
Calabrese
Carlo
C
Martinoli
D000328:Adult; D000368:Aged; D001917:Brachial Plexus / Q000473:pathology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies