May 6, 2009 -- A surgically implanted pump that delivers medication to the spinal fluid helps reduce the persistent pain that can linger in some patients after they recover from shingles, according to a new study.
"All patients showed a greater than 50% improvement in pain control," says Andrew J. Fabiano, MD, a senior resident at the University of Buffalo who was scheduled to present the findings yesterday at the American Association of Neurological Surgeons meeting in San Diego. "The patients describe a dramatic improvement in pain,'' he says. The study follow-up averaged nearly six years.
Shingles affects about a million people a year in the U.S., according to the Association for Healthcare Research and Quality, with risk being much higher for people 65 and older.
Shingles occurs when the varicella zoster virus that causes chickenpox reactivates and causes a painful rash on the trunk or other body parts. In about 15% of patients, Fabiano says, the pain persists a month or longer, a condition called postherpetic neuralgia or post-shingles pain. (A shingles vaccine, Zostavax, is now recommended for certain people by the CDC.)
Fabiano and his colleagues evaluated five patients -- one woman and four men -- all of whom had post-shingles pain. Their average age was 75 and none had been helped enough by the typically prescribed oral pain medications given for the condition.
They decided to study the pump system, already on the market and used for other chronic pain conditions, after finding little published on it for post-shingles pain.
They implanted a pump, "about the size of a hockey puck," Fabiano says, in a procedure that takes about 45 minutes. The pump is placed under the skin, typically in the abdomen, and is attached to a small tube inserted into the spine. The medication goes from the pump through the tube and enters the spinal fluid.
Before the pump was implanted, all patients were given a trial, Fabiano says, either by injecting the pain medicine into the spinal area or placing a temporary catheter to deliver the medication for 24 or 48 hours to be sure the medicine worked for their pain.