A team of researchers said Wednesday it has succeeded in using a specially treated high polymer sheet to permanently repair severed blood vessels.

The team, led by Osaka University assistant professor Yoshiki Sawa, presented the findings at a meeting in Kobe of the Japanese Society for Regenerative Medicine.

The team included researchers from Osaka University and the National Institute of Advanced Industrial Science and Technology.

It created the repair technique by treating a meshed high polymer sheet, the type used in hernia surgery, to fill the abdominal cavity, with collagen -- a fibrous protein found in connective tissues -- so that cells can grow on the material.

The team applied the collagen-treated high polymer sheet to seal a hole in the lung artery of a dog. Two months later, the research found the hole had sealed with regenerated cells, with the polymer sheet dissolving and being absorbed by the body.

The method, if it pans out, would eliminate the need for repeated surgery for patients who undergo heart vessel operations, the researchers said.

Doctors currently use heart sacs taken from cows and horses to repair severed blood vessels. The material, however, tends to calcify over time and needs to be replaced every five to 10 years, according to Shigemitsu Iwai, an Osaka University researcher who took part in the project.

There has been no sign of calcification in the dog's lung artery that was treated with the new sealing procedure, Iwai said.

"We still need to monitor the long-term progress, but we hope to conduct clinical tests eventually," he said.

Iwai said the researchers plan to make improvements on the high polymer sheet, making it usable to repair curving or branching blood vessels.