Tagliafico et al [44] in a blinded, retrospective review studied 157 patients who underwent brachial plexus MRI found an overall sensitivity of 81%, specificity of 91%, positive predictive value of 82%, negative predictive value of 91%, and accuracy of 88% when compared with the reference standard of surgical findings and clinical follow-up. Du et al [45] in a retrospective review studied 191 patients and found that the brachial plexus MRI provided additional information beyond that of clinical evaluation and electrodiagnostic studies in 45% of patients. Hilgenfeld et al [46] in a blinded, retrospective review studied 36 patients and found that brachial plexus MRI could reliably differentiate compressive from noncompressive plexopathy in all patients. MRI with and without IV contrast can be useful for detecting and characterizing several of the etiologies in the differential diagnosis of nontraumatic brachial plexopathy and may provide additional information over MRI without IV contrast in this setting [47]. US Neck There is no relevant literature to support the use of ultrasound (US) as the primary imaging modality for patients with nontraumatic brachial plexopathy in whom clinical and electrodiagnostic evaluation has been inconclusive. US may be a useful supplemental test in selected centers [50]. US has been described as an adjunctive tool for assessment of nerve enlargement in patients with a clinically diagnosed neuropathy [30,35,39,51-55]. US can be very useful for image-guided therapy, including regional anesthesia, which is beyond the scope of this topic. Variant 2: Lumbosacral plexopathy, acute or chronic, nontraumatic. No known malignancy. Initial imaging. This variant encompasses nontraumatic lumbosacral plexopathy occurring in patients without a history of systemic malignancy or post-treatment syndrome.
Plexopathy. Tagliafico et al [44] in a blinded, retrospective review studied 157 patients who underwent brachial plexus MRI found an overall sensitivity of 81%, specificity of 91%, positive predictive value of 82%, negative predictive value of 91%, and accuracy of 88% when compared with the reference standard of surgical findings and clinical follow-up. Du et al [45] in a retrospective review studied 191 patients and found that the brachial plexus MRI provided additional information beyond that of clinical evaluation and electrodiagnostic studies in 45% of patients. Hilgenfeld et al [46] in a blinded, retrospective review studied 36 patients and found that brachial plexus MRI could reliably differentiate compressive from noncompressive plexopathy in all patients. MRI with and without IV contrast can be useful for detecting and characterizing several of the etiologies in the differential diagnosis of nontraumatic brachial plexopathy and may provide additional information over MRI without IV contrast in this setting [47]. US Neck There is no relevant literature to support the use of ultrasound (US) as the primary imaging modality for patients with nontraumatic brachial plexopathy in whom clinical and electrodiagnostic evaluation has been inconclusive. US may be a useful supplemental test in selected centers [50]. US has been described as an adjunctive tool for assessment of nerve enlargement in patients with a clinically diagnosed neuropathy [30,35,39,51-55]. US can be very useful for image-guided therapy, including regional anesthesia, which is beyond the scope of this topic. Variant 2: Lumbosacral plexopathy, acute or chronic, nontraumatic. No known malignancy. Initial imaging. This variant encompasses nontraumatic lumbosacral plexopathy occurring in patients without a history of systemic malignancy or post-treatment syndrome.