Injecting nerves with radiological contrast as a novel method of studying the peripheral nervous system.

The peripheral nervous system has been the subject of various studies on topics ranging from the innervation of tissues and organs to central nervous system clearance and neuropathies. Because research methods are mainly based on dissection techniques accompanied by histological studies, they inevitably lead to the destruction of the tissue under study. Our team has developed a method consisting of injecting peripheral nerves with barium contrast that can be visualized with computed tomography (CT) scans. We infused unfixed specimens of the vertebral column with contrast agent, subsequently scanned them via a CT system, and finally created three-dimensional models, which included the spinal nerves (including the ganglia, the communicating branches, and the rami of the spinal nerve), the intercostal nerves, the plexuses (brachial, lumbar, and sacral) and the sympathetic trunk. The obtained spatial models are characterized by high didactic values and can be used for academic and postgraduate purposes (e.g., teaching medical students, planning peripheral nerve blocks, analysis of zygapophysial joints innervation). The method leaves the samples intact and facilitates further analyses by allowing noninvasive selection of areas of interest (e.g., targeted dissection, histological studies, and micro-CT). We provide a step-by-step description of this method, including injecting the peripheral nerves and subsequently obtaining three-dimensional models.