Device used to treat swelling is also used to zap fat.

(NBC) - A four-armed laser with red beams. Can it zap fat ... no pain ... no surgery?

Stefani Martinez is a firm believer. She says she dieted and exercised, but had stubborn fat that wouldn't budge.

She underwent six, 40 minute sessions at UT Southwestern Medical Center in Dallas over two weeks.

"I saw results in the third session. At the very last session, I saw a dramatic change," Martinez said.

Three inches in the hips, two and a half in the thighs, she says.

The Zerona laser -- FDA approved to treat pain and inflammation after surgeries -- is now, according to its maker, forcing fat out of cells.

Doctor Jeffrey Kenkel, Vice-Chairman of plastic surgery at UT Southwestern has conducted several clinical trials on Zerona and says about 90 percent of patients saw dramatic results.

"Some of the fat actually leaches out of the fat cells and is taken up by your body and re-used in other ways," Dr. Jeffrey Kenkel said.

Using a 3-d measuring machine, three-thousand measurements were taken ... yielding scientific results.

"Are the results the same as what we would get with liposuction, probably not. I think we have to be cautious here. I think it's an alternative for patients who may be a little bit closer, but still have some problem areas and are not necessarily interested in surgery," Dr. Kenkel said.

While many doctors are marketing and using Zerona to zap fat-- it is not FDA approved for that use.

"We use a lot of products as an "off label" use if the physicians are well educated. Obviously, we need to tell our patients that, that this is an off label use. When the FDA will make a ruling on this, it's really hard to know," Dr. Kenkel said.

Kenkel says Zerona is safe. But how long the results last -- is up to the patient.

"We haven't destroyed the fat cells with this device, so there is a good chance that you can regain weight in that area," Dr. Kenkel said.

Stefani is determined to keep those inches off!

"It only works if you are dedicated and determined to keep the weight off. It's fast, it's easy and it's painless," she said.

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