Effect of temporary spinal cord stimulation on postherpetic neuralgia in the thoracic nerve area

Objectives.  The pain associated with herpes zoster can be classified as acute phase, persistent phase, or chronic phase, but if it is prolonged, it becomes resistant to treatment. It is clinically important to prevent transition to postherpetic neuralgia after the onset of herpes zoster, and the outcome depends on whether continuous and potent pain management can be achieved between the acute and persistent phases. We evaluated the effect of pain management leading to quick termination of pain using temporary spinal cord stimulation (SCS) which does not require implantation of a device. Materials and Methods.  We performed continuous epidural blocks (CEB) on 52 patients with severe persistent pain of postherpetic neuralgia in the thoracic nerve area, and also inserted spinal stimulation leads in 14 who showed no improvement in the severe pain with concomitant pharmacotherapy. We expected to see the termination of pain with adequate analgesic effects mainly with SCS, and secondarily with the epidural analgesia as rescue therapy. Results.  Severe pain accompanied by sensory dysfunction remained in 14 cases. By introducing SCS to the CEB, the visual analog scale baseline was rapidly reduced. Less epidural analgesia was required and the adverse reactions of lowered blood pressure in three cases and urinary retention in seven cases disappeared soon. The self-rated satisfaction was higher with SCS than with CEB in all 14 cases, because it is highly controllable and has minimal activities of daily living-lowering effects. Conclusion.  Temporary SCS, which does not require implantation of a device, may have a potent analgesic effect on severe pain in patients in the persistent phase after herpes zoster, and prevent transition to postherpetic neuralgia.