Imaging of peripheral nerve lesions.

The imaging of peripheral nerve lesions remains limited to the radiographic demonstration of secondary skeletal lesions in birth trauma, reflex sympathetic dystrophy, neuropathic arthropathy, leprosy, and congenital indifference to pain. Nerve root avulsions can be imaged directly and the newer imaging modalities now allow delineation of lesions that previously could not be studied using conventional radiography. The ability of ultrasound, CT, and MRI to differentiate soft tissue structures makes it possible, in many instances, to study the primary abnormality in trauma, nerve entrapment syndromes, and tumors. With fractures, the possibility of trauma to adjacent nerves can only be inferred on the radiographs, while the role that peripheral nerve injury plays remains controversial in other entities, such as amputation with replantation. Imaging of peripheral nerve lesions remains in its infancy. With further refinement in the signal-to-noise ratio made possible by advances in MRI technology, we may be optimistic about future imaging of peripheral nerve pathology.