With few options available at home in America, they search the Internet for experimental treatments - and often land on websites promoting stem cell treatments in China.

They mortgage their houses and their home towns hold fund-raisers as they scrape together the tens of thousands of dollars needed for travel and the hope for a miracle cure.

A number of these medical tourists claim some success when they return home:

Mr Jim Savage, a Houston man with paralysis from a spinal cord injury, says he can move his right arm now.

Ms Penny Thomas of Hawaii says her Parkinson's tremors are mostly gone.

The parents of six-year-old Rylea Barlett of Missouri, born with an optical defect, say she can now make out blurry images on TV.

But documentation is mostly lacking, and Western doctors warn that patients are serving as guinea pigs in a country that is not doing the rigorous lab and human tests that are needed to prove a treatment is safe and effective.

Noting the lack of evidence, three Western doctors undertook their own limited study.

It involved seven patients with spinal cord injuries who chose to get fetal brain tissue injections at one hospital in China.

The study reported 'no clinically useful improvements' - even though most patients believed they were better. Five developed complications such as meningitis.

Experts in the West have theories about why some people think they have improved when the evidence is thin.

Some are often getting intensive physical therapy along with the mysterious injections; the placebo effect may also be a factor.

Professor John Steeves of the University of British Columbia, who heads an international group that monitors spinal cord treatments, has another theory.

Some patients may be influenced by the amount of money they paid and the help they received from those who donated or helped raise money.

'Needless to say, when they come back, what are they going to report to their friends and neighbours? That it didn't work?' said Prof Steeves.

He and other experts have written a booklet advising patients who are considering such treatments.

Western doctors discourage their patients from seeking the treatments. They note that it is impossible to gauge the safety of the treatments, or even to know what is in the injections put into brains and spinal cords.

However, patients and their families say they accept these risks as they simply do not have time to wait for more conclusive evidence.

For many, the trip to China is a journey of hope.

'It's one of the only games in town,' said Mr Savage, 44, a lawyer who suffered severe spinal cord injuries during a canoe trip 25 years ago.

He spent 2-1/2 months in late 2006 and early last year at a hospital in the southern Chinese city of Shenzhen to get what he was told were stem cell injections in his spine from umbilical cord blood.

He made the arrangements through Beike Biotechnology Co, which offers the treatments at a number of hospitals in China.

Afterwards, Mr Savage said he was able to move his right arm for the first time since his diving accident.

Just how many foreigners like Mr Savage are coming to China for treatment is not known.

The use of stem cells in treatments is not new. For decades, doctors around the world have been using adult stem cells from blood and bone marrow - and more recently from umbilical cord blood - to treat cancers of the blood.

But whether any clinics in China are using the more controversial embryonic stem cells is not clear.

Such stem cells are taken from days-old embryos. They can develop into all types of cells, but research into their usefulness is in the early stages.

Beike founder Sean Hu, who returned from abroad in 1999 with a doctorate in biochemistry, said the company has treated more than 1,000 patients, including 300 foreigners from 40 different countries.

'Patients shouldn't have their expectations too high,' Dr Hu said. 'For patients to think they can walk again may be too much at this stage.'

Dr Hu, who is seeking venture capital to expand his web of treatment centres, labs and doctors and adapt proprietary techniques from researchers overseas, added: 'There is real potential here for China to take the lead in stem cells.'

Also offering treatments is Tiantan Puhua in Beijing, a joint venture between Asia's largest neurological hospital and an American medical group.

The hospital says its stem cell injections are combined with daily three-hour doses of intravenous drugs designed to stimulate production of the patient's own stem cells. Physical therapy and Chinese medicine are also part of the plan.

A standard two-month course of treatment costs up to US$35,000 (S$50,000).

'We are giving them another option at the highest level of safety,' said Dr Sherwood Yang, head of the hospital's management team.

Ms Thomas, 53, sought treatment for Parkinson's disease at Tiantan. There, doctors drilled into her skull and injected what she was told were cells from a donor's retina.

One year later, she said her tremors are almost gone and her medication has been cut to one half of a single pill.

'I have no regrets and would do it all over again if need be,' she said.

ASSOCIATED PRESS