Relief from neuropathic pain by irradiation with linear polarized near infrared rays

For treatment of chronic pain, a variety of stimulatory and medical therapies have been applied in addition to sensory nerve block and sympathetic nerve block, and their usefulness is widely recognized. However, these procedures may produce side effects. Walker suggested that low-power laser irradiation for chronic pain syndrome was effective, although the mechanism of analgesic action has not yet been clariŽ ed. Laser therapy is a safe, effective, and comfortable treatment. We performed a pilot linear polarized light therapy on a patient with neuropathic pain after the patient gave his informed consent. A 30-yr-old, 75-kg, 165-cm male had a one-year history of neuropathic pain due to a lesion of the left supraorbital nerve associated with tic douloureux. The nerve damage was caused by a trauma which occurred during childhood. There were no abnormal Ž ndings on imaging examinations. When pain was severe, the patient was treated with diclofenac sodium 25 mg. However, this drug had no analgesic effect with passing of time. We performed light therapy using Super LizerTM (HA-550 of KSK Tokyo Iken, Japan). Super LizerTM is a Ž rst linear polarized near infrared ray therapeutic equipment, as shown in Fig. 1. The wavelength range is 600–1600 nm