Plexiform neurofibroma in neurofibromatosis type-1 (NF-1). Plexiform neurofibroma in neurofibromatosis type-1 (NF-1). A 36-year-old man with known NF-1 presenting with right shoulder and neck pain with weakness of the arm. Coronal postcontrast fat-suppressed T1-weighted image shows a large infiltrative mass showing a “bag of worms” appearance (large arrows), encasing the brachial plexus (small arrow), in keeping with a plexiform neurofibroma. A. Chhabra et al. AJNR Am J Neuroradiol 2013;34:486-497 ©2013 by American Society of Neuroradiology