A neurolytic block is a method of controlling pain or other distressing neurological symptoms by chemically or physically damaging or destroying nerves. It is usually used to treat cases of chronic and refractory pain. Chemical neurolysis can be performed by administering injections of phenol, alcohol or other agents that damage nerve structure. Nerve damage can also be brought about by cryoablation (freezing), radiofrequency ablation (heat) or surgery. The effects of a neurolytic block may be permanent or temporary depending on whether the nerve is allowed to regenerate.
Neurolytic blocks can treat severe pain associated with cancer or disabling pain such as chronic abdominal pain, pain following chest trauma or spine pain resistant to other forms of therapy. Blocks are also administered to treat conditions such as spasticity (stiffening of muscles) to improve muscle control and balance.
Before performing a neurolytic block your doctor will assess your symptoms and history and perform a nerve block to temporarily anesthetize the offending nerve. This helps confirm the nerve responsible for pain and gives you an idea of the kind of pain relief you can expect. Preparation is then made for the neurolytic block. For chemical neurolysis, the skin over the area is cleaned and anesthetized. The injection containing the neurolytic agent is then administered directly or under the guidance of X-ray imaging. Care is taken to limit the spread of the neurolytic agent. Physical neurolysis is performed with the help of a special needle or probe which delivers heat or cold in a controlled manner. Surgical neurolysis involves making an incision and cutting off or damaging a part of the nerve with instruments. Pain relief following the procedure may last weeks to months.
As with any procedure, neurolytic blocks can be associated with certain complications that include nerve damage affecting movement, numbness, painful inflammation of the nerve (neuritis), and temporary sexual or bowel and bladder dysfunction. However, neurolytic blocks often improve quality of life and function.