SUMMARY: With advancement in 3D imaging, better fat-suppression techniques, and superior coil designs for MR imaging and the increasing availability and use of 3T magnets, the visualization of the complexity of the brachial plexus has become facile. The relevant imaging findings are described for normal and pathologic conditions of the brachial plexus. These radiologic findings are supported by clinical and/or EMG/surgical data, and corresponding high-resolution MR neurography images are illustrated. Because the brachial plexus can be affected by a plethora of pathologies, resulting in often serious and disabling complications, a better radiologic insight has great potential in aiding physicians in rendering superior services to patients.

BACKGROUND AND PURPOSE: A number of benign and malignant peripheral nerve tumor and tumorlike conditions produce similar imaging features on conventional anatomic MR imaging. Functional MR imaging using DTI can increment the diagnostic performance in differentiation of these lesions. Our aim was to evaluate the role of 3T anatomic MR imaging and DTI in the characterization of peripheral nerve tumor and tumorlike conditions. MATERIALS AND METHODS: Twenty-nine patients (13 men, 16 women; mean age, 41 ± 18 years; range, 11–83 years) with a nerve tumor or tumorlike condition (25 benign, 5 malignant) underwent 3T MR imaging by using anatomic (n = 29), functional diffusion, DWI (n = 21), and DTI (n = 24) techniques. Images were evaluated for image quality (3-point scale), ADC of the lesion, tractography, and fractional anisotropy of nerves with interobserver reliability in ADC and FA measurements. RESULTS: No significant differences were observed in age (benign, 40 ± 18 versus malignant, 45 ± 19 years) and sex (benign, male/female = 12:12 versus malignant, male/female = 3:2) (P > .05). All anatomic (29/29, 100%) MR imaging studies received “good” quality; 20/21 (95%) DWI and 21/24 (79%) DTI studies received “good” quality. ADC of benign lesions (1.848 ± 0.40 × 10⁻³ mm²/s) differed from that of malignant lesions (0.900 ± 0.25 × 10⁻³ mm²/s, P < .001) with excellent interobserver reliability (ICC = 0.988 [95% CI, 0.976–0.994]). There were no FA or ADC differences between men and women (P > .05). FA of involved nerves was lower than that in contralateral healthy nerves (P < .001) with excellent interobserver reliability (ICC = 0.970 [95% CI, 0.946–0.991]). ADC on DTI and DWI was not statistically different (P > .05), with excellent intermethod reliability (ICC = 0.943 [95% CI, 0.836–0.980]). Tractography differences were observed in benign and malignant lesions. CONCLUSIONS: 3T MR imaging and DTI are valuable methods for anatomic and functional evaluation of peripheral nerve lesions with excellent interobserver reliability. While tractography and low FA provide insight into neural integrity, low diffusivity values indicate malignancy in neural masses.

The addition of functional sequences to the conventional MR imaging protocol may increase sensitivity for determination of treatment response in soft-tissue sarcomas treated preoperatively with neo... Purpose To determine the added value of quantitative diffusion-weighted and dynamic contrast material–enhanced imaging to conventional magnetic resonance (MR) imaging for assessment of the response...

This article summarizes the claims and procedures of the Musculoskeletal Biomarker Committee Profile of the Quantitative Imaging Biomarkers Alliance for standardized MRI-based cartilage composition... MRI-based cartilage compositional analysis shows biochemical and microstructural changes at early stages of osteoarthritis before changes become visible with structural MRI sequences and arthroscop...

OBJECTIVE. The sciatic nerve may normally exhibit mild T2 hyperintensity in MR neurography (MRN) images, rendering assessment of sciatic neuropathy difficult. The purpose of this case-control study was to evaluate whether a quantitative and qualitative analysis of the sciatic nerves and regional skeletal muscles increases the accuracy of MRN in detecting sciatic neuropathy. MATERIALS AND METHODS. We retrospectively reviewed the MRN studies of the pelvis and thighs of 34 subjects (12 men and 22 women; mean [± SD] age, 50 ± 15 years), of which 17 had a final diagnosis of sciatic neuropathy according to electrodiagnostic or surgical confirmation, and 17 had no evidence of sciatic neuropathy and served as control subjects. On each side, the sciatic nerves were evaluated for signal intensity (SI), size, course, and fascicular shape, whereas the regional skeletal muscles were evaluated for edema, fatty replacement, and atrophy. In addition, the nerve-to-vessel SI ratio was registered for each side at the same t...