A
neurolytic block is a form of
nerve block involving the deliberate injury of a nerve by the application of chemicals (in which case the procedure is called "
neurolysis") or physical agents such as freezing or heating ("
neurotomy"). These interventions cause degeneration of the nerve's fibers and temporary (a few months, usually) interference with the transmission of nerve signals. In these procedures, the thin protective layer around the nerve fiber, the
basal lamina, is preserved so that, as a damaged fiber regrows, it travels within its basal lamina tube and connects with the correct loose end, and function may be restored. Surgical cutting of a nerve (
neurectomy), severs these basal lamina tubes, and without them to channel the regrowing fibers to their lost connections, over time a painful
neuroma or deafferentation pain pain may develop. This is why the neurolytic is usually preferred over the surgical block.