Christchurch doctors develop fat-firming plastic surgery technique

A patient's own fat can be a crucial "filler" in any reconstructive surgery, and particularly for women who have undergone a mastectomy.

But the fat often gets absorbed into the patient's body and they have to go under the knife over and over to replace it.

But now, two Christchurch doctors have come up with a way to make the fat firmer to enable it to hold its shape better and last longer. 

The technique involves taking fat out and treating it with a special chemistry that's been developed, biomedical engineer Khoon Lim says. A bright light is then shone on the fat to firm it up before it's reinjected into the patient.

Fat grafting involves taking tissue from the body, then reinjecting it back into the area where it's needed for reconstruction. It's the safest option, but it's difficult. 

"The fat is soft and blobby and squishy. It sort of all gets mushed together," Lim says.

Unfortunately, the fat is easily reabsorbed back into the body and reconstructions lose shape.

Some patients have to go under the knife as many as six times to get the right result. 

"We'd love to get it down to one operation. Even if we can get it down to one or two operations instead of three or four, it's a big difference for patients," plastic surgeon Jeremy Simcock says.

The new technique makes the fat firmer before it's reinjected, which gives the surgeon more precision and patients another option.

"It certainly would have been an option I might have considered more. The results, the recovery, they're all things that factored into my decision," breast cancer survivor Maree van Royen says.

She was just 30 years old when she was diagnosed with breast cancer and she opted for a double mastectomy.

"I was presented with a lot of overwhelming information at the time and you weigh up benefits and risks," she says.

"[I was] not wanting to have constant revision surgeries afterwards. The implants' reconstruction, that was what I thought was the best option for me. It does give natural pleasing results."

The technique may eventually be used for other reconstructions too.

"If someone's had a gland removed from the cheek, then they lose a contour. Then they can be filled up with fat grafting," Simcock says.

If the year-long project is successful, it could be only a matter of time before the technique goes from the lab to the operating theatre.

The University of Otago has also stumped up $50,000 to help their research.