title: Caudal Epidural of Pulsed Radiofrequency in Post Herpetic Neuralgia (PHN); Report of Three Cases.
abstract: BACKGROUND
  Postherpetic neuralgia (PHN) is a frequently occurring neuropathic pain, its pathophysiology is not fully understood. There are only few evidence based therapeutic options; sympathetic nerve block can be considered for patients with PHN refractory to conservative treatment, but long-term effects are poor. Application of pulsed radiofrequency was effective to treat a variety of pain syndromes without neurological complications or other sequelae.
  
  
  METHODS
  We observed a remarkable long-lasting pain relief in patients with post herpetic neuralgia (PHN) treated with caudal epidural PRF. We described the technique of caudal epidural PRF and three case reports.
  
  
  CONCLUSIONS
  The mode of action of PRF is far from being completely elucidated. The high frequency current induces an electric field that in turn seems to influence the immunity, the inflammation and other pain conducting mechanisms. Our findings suggest an effect distal from the application of the current. It reaches targets that are difficultly attainable by any other means of current application. The observations of pain relief in the difficult to treat patients with PHN justifies further investigation.
authors.affiliation: Pain Clinic, Orbis Medical Center, Sittard Geleen, The Netherlands.
authors.forename: Olav Jacobus Johannes Maria
authors.initials: OJ
authors.lastname: Rohof
keywords: Anesthesia, Caudal; Chronic Pain; Neuralgia, Postherpetic; Pulsed Radiofrequency Treatment