An experimental stem cell treatment, currently only performed at an ageing public hospital in Portugal, is raising hopes that thousands left paralysed by accidents will once again be able to walk. The procedure involves the removal of tissue from a patient's nasal cavity, which is rich in adult stem cells, and implanting them in the spinal cord at the site of an injury.
As stem cells have the capacity to become any type of cell, the implanted stem cells have the potential to become nerve cells, replacing those damaged in the accident.
"Most of the work is done by nature. It is an extremely natural and simple method," explained neurologist Carlos Lima, chief of the surgical team which conducts the procedure, at his cramped office at Lisbon's riverside Hospital de Egas Moniz.
Preliminary results are promising.
The surgical team has performed the six-hour surgery 41 times since July 2001. There have been no infections or deaths and all patients have reported some degree of increased feeling since their surgery.
Roughly 10 percent of the patients are now able to walk with the aid of a walker or other supportive device.
Lima said he expects one of these patients, a woman who travelled to Lisbon from the US state of Texas for the procedure, will be able to walk completely on her own later this year.
"To see something happen which was considered perfectly impossible before is a spectacular sensation," he told AFP.
But he cautions that the success of the operation is highly dependent on patients undergoing intensive physical therapy for up to two years to enable muscles which have not been used in years to regain their strength.
Lima, 49, is not yet sure if the gains made after an operation will be permanent but he is increasingly optimistic that they will be long-lasting since no patient has regressed since having the procedure.
The surgery has drawn the attention of people from around the world, from Iceland to Italy, who have headed to the Portuguese capital to have it done.
Twenty-year-old Amy Foels, who was paralysed from her waist down in a car accident in November 2002, travelled to Lisbon last month from the US to have the procedure performed after she learned about it in a television report.
Since having the operation, which cost her family some 50,000 dollars (38,000 euros) in medical and travel expenses, Foels reports feeling a tingling sensation in her legs which she said seems to grow stronger when she focuses on moving either her legs or toes.
She is preparing to start months of aggressive rehabilitation and plans to finish her college studies and one day get married.
"But not in my wheelchair," she said in an e-mail sent from her parents' home in Elkader, Iowa.
"After having the surgery I feel really good about myself. I took a chance that a lot of people may not get and hopefully good things will come from it."
Only patients 35 and younger, and who have been injured for six years or less, are eligible for the surgery although Lima is considering changing this criteria so that people who have been injured for longer may qualify.
The surgery may soon be available in more nations as well. A hospital in Colombia and another in New Zealand are expected to start performing the operation later this year, he said.
"I always believed this would work," said Lima, who got his degree from Lisbon's Universidade Nova and has spent nearly two decades developing the procedure at the Egas Moniz hospital.