A newly developed surgical technique can help some people with facial paralysis regain muscle movement in their face, with some patients able to smile again within a week of surgery, researchers said on Monday.

The technique is called temporalis tendon transfer and has several advantages over existing procedures to address facial paralysis, including quick restoration of some muscle movement, they said.

A team led by Dr. Patrick Byrne at Johns Hopkins University School of Medicine in Baltimore called it a relatively fast and easy procedure to reanimate facial muscles with less recuperation time and better results than existing techniques.

They restored the smiles of six out of seven patients affected by brain tumors, Byrne's team reported in the Archives of Facial Plastic Surgery.

The procedure also gives patients with facial paralysis -- the loss of voluntary muscle movement, generally on one side of the face -- improved facial symmetry, Byrne said.

"The ability to smile is what patients are most troubled by with facial paralysis," Byrne said in a telephone interview, adding that these patients can regain the ability to smile within a week of the operation.

The operation often may be performed in a minimally invasive manner and avoids the facial deformity produced by an existing operation, the researchers said.

The procedure does not completely restore facial muscle function, but patients are pleased with how much they are able to move these muscles, Byrne said.

"In reality, facial paralysis is a condition for which we don't have tremendous answers," Byrne said.

"The face is so nuanced and complex. There are 39 muscles affected by complete facial paralysis on one side. We just can't restore the incredibly nuanced emotional expressiveness that we'd like to," Byrne added.

Byrne and his team described seven patients who underwent the procedure starting in 2004. Nine others not in the paper also have had the surgery with similar good results, Byrne said.

Common causes of facial paralysis include a condition called Bell's palsy, stroke and brain tumors. Six of the seven brain tumor patients regained the ability to smile, Byrne said.

Bell's palsy, the most common cause of facial paralysis, results from damage or trauma to one of the two facial nerves, but most people recover completely within months.

Byrne said relatively few stroke patients get surgery for facial paralysis because many have medical conditions making any operation risky.

"It's most appropriate for patients who have facial paralysis of long-standing duration," Byrne added, saying people with facial paralysis in place for one to two years are less likely to be helped by other procedures.