But California radiologist Michael Arata and other doctors are continuing to treat a condition dubbed "chronic cerebrospinal venous insufficiency," or CCSVI, on dozens of new patients, based on their conviction that it offers a better quality of life.

The experimental technique, introduced three years ago, uses angioplasty balloons or stents to open up narrowed and twisted veins in the neck and chest to help blood drain from the brain. In its warning last May, the Food and Drug Administration said there is no clear evidence CCSVI exists in MS patients, and the procedure to treat it has not been shown to be safe or to help patients.

Arata argues that in 90 percent of about 1,200 cases he was involved in, the technique helped alleviate symptoms such as fatigue, "brain fog" and headache in patients suffering from MS, Parkinson's disease and other neurological conditions. Eighty of those treatments were delivered after the FDA warning, at a cost of up to $10,000 apiece, which is often not covered by insurance.

"I am convinced that there is a benefit," he added. "I am also convinced that it's safe."

Asked for comment on the continued use of CCSVI treatment, FDA spokeswoman Michelle Bolek said the agency does not regulate the practice of medicine and that doctors have significant leeway to use an approved medical device for treatments not specified on its label. The agency said doctors need to fully inform patients of the FDA's concerns.

"We are not seeking approval of a new use. This has nothing to do with the FDA," said Arata, who practices at Synergy Health Concepts in Newport Beach. "They have absolutely no jurisdiction."

DEGREE OF RISK

One of Arata's MS patients died after suffering bleeding in the brain several days after a CCSVI treatment last year. Arata attributed her death to the blood thinners used to prevent clots after CCSVI procedures, which he said have life-threatening effects in three or four out of 1,000 cases, compared with his experience of a single patient out of 1,200.

"If you have an invasive procedure, you can't take it lightly," Arata said. "We accept some degree of risk with any therapy."

Aisha Johnson, 35, was diagnosed with MS in 1997 and underwent CCSVI treatment by Arata earlier this month. She said she was informed of the FDA warning, but the hope of improvement won out.

"I have already noticed little changes. ... One day I was typing on the computer and halfway through kind of stopped and said, ‘Wait a minute, my hands aren't trembling as much,'" she said. "Every day I am kind of noticing little differences."

Synergy Health advertises its CCSVI procedures online, as does Community Care Physicians in Albany, New York, whose representatives did not respond to requests for comment. Experts familiar with the procedure said they knew of other doctors who had performed the treatment on patients since the FDA warning but would not provide names.

"There are some places that are doing it," said Dr. Robert Fox, staff neurologist and medical director at the Mellen Center for Multiple Sclerosis at Cleveland Clinic in Ohio. He warns his patients against the vein-opening treatment because "there have been more negative reports on the association of CCSVI with MS than there are positive."

A Canadian review of eight studies found wide variations in the degree to which CCSVI was detected in MS patients. Canada is preparing its own research into the effectiveness of the procedure on about 100 patients.

The FDA said it has received a report of one patient who died from bleeding in the brain and one who suffered permanent paralysis after CCSVI therapy. It cited a second death reported by medical journals, as well as serious complications such as blood clots and nerve damage.

Stanford University's CCSVI program was shut down in late 2009 after it acknowledged that one patient died of a brain hemorrhage and another needed emergency open-heart surgery after a stent migrated from the jugular vein to his heart. Last month two patients sued the university and Dr. Michael Dake, medical director of its catheterization and angiography laboratories, for performing dangerous experimental procedures on essentially healthy veins without properly informing patients of the risks.

"Dake really didn't consult with some of the other (doctors) who were further along with this," said Mark Wittwer, a co-plaintiff in that lawsuit who lost complete use of his right jugular vein. "A lot of this could have been avoided."

Stanford and Dake declined comment. Medical device maker Johnson & Johnson said it was not aware of its stents or angioplasty balloons being used for treating CCSVI, while Abbott Labs, which also makes those products, said it does not have a research program involving CCSVI. Officials at device maker Medtronic Inc did not respond to requests for comment.

QUESTIONING THE DATA

Multiple sclerosis has long been attributed to a glitch allowing the immune system to mistakenly attack the myelin sheath protecting nerve cells. It affects 2.5 million people globally with symptoms ranging from numbness or weakness in the limbs to loss of vision and an unsteady gait or even paralysis.

Current drugs act to delay the worsening of symptoms. Treatments like beta-interferon cause flu-like symptoms while a newer drug, Biogen's Tysabri, can cause a rare but fatal brain disease.

In 2009, Italian researcher Dr. Paolo Zamboni linked MS to CCSVI, a term he invented. The theory is that veins bringing blood from the brain and spine back to the heart become too narrow, causing some of that blood to leak into the brain tissue. Zamboni and his colleagues figured that might trigger inflammation, eventually leading to the balance and muscle problems seen in MS.

Zamboni did not respond to requests for comment.

Arata theorizes that the vein-opening treatment may help patients with a range of neurological conditions through its effect on the segment of the nervous system that controls involuntary actions.

The Cleveland Clinic is studying how best to diagnose CCSVI and whether dehydration has an impact on vein status, with some trial data due later this month at a conference in Lyon, France.

Some scientists have already made up their minds.

"If (CCSVI) were a risk factor, then it would be consistently found in patients with MS," said Klaus Schmierer, a neurologist at Queen Mary, University of London, who has worked on CCSVI studies.

In a recent report, the U.S. National MS Society wrote: "At this point, no connection has been confirmed between CCSVI and MS, in fact, CCSVI appears to occur in many people who do not have MS."

(Reporting by Deena Beasley and Genevra Pittman of Reuters Health; Editing by Michele Gershberg and Prudence Crowther)

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