What is Post Herpetic Neuralgia
Neuralgia is pain in one or more nerves caused by a change in neurological structure or function of the nerves rather than by excitation of healthy pain receptors. Neuralgia falls into two categories: central neuralgia, where the cause of the pain is located in the spinal cord or brain, and peripheral neuralgia. This unusual pain is thought to be linked to four possible mechanisms: ion channel gate malfunctions; the nerve fibers become mechanically sensitive and create an ectopic signal; signals in touch fibers cross to pain fibers; and malfunction due to damage in the brain and spinal cord.
- burning
- hypersensitivity
- stabbing
- gnawing
- muscle weakness
Pain that continues for 3 months or more. Pain is variable from discomfort to very severe and may be described as burning, stabbing, or gnawing. Sensation may be altered over involved areas, in the form of either hypersensitivity or decreased sensation. In rare cases, the patient might also experience muscle weakness, tremor or paralysis — if the nerves involved also control muscle movement.
Treatment options include medicines and surgery.
High doses of anticonvulsant medicines—used to block nerve firing— and tricyclic antidepressants are generally effective in treating neuralgia. If medication fails to relieve pain or produces intolerable side effects, surgical treatment may be recommended.
Neural augmentative surgeries are used to stimulate the affected nerve. By stimulating the nerve the brain can be “fooled” into thinking it is receiving normal input. Electrodes are carefully placed in the dorsal root and subcutaneous nerve stimulation is used to stimulate the targeted nerve pathway. A technician can create different electrical distributions in the nerve to optimize the efficiency, and a patient controls the stimulation by passing a magnet over the unit.
Some degree of facial numbness is expected after most of these surgical procedures, and neuralgia might return despite the procedure’s initial success. Depending on the procedure, other surgical risks include hearing loss, balance problems, infection, and stroke. These surgeries include rhizotomy (where select nerve fibers are destroyed to block pain) and Microvascular decompression (where the surgeon moves the vessels that are compressing the nerve away from it and places a soft cushion between the nerve and the vessels).
