A laser that is normally used in tattoo removal can also treat facial scarring from acne, according to a new study.

In the study, researchers tested the device, called a picosecond pulse duration laser, on 17 people who had facial acne scars. Researchers applied the laser to the patients' faces a total of six times, with the sessions coming four to eight weeks apart. Each application took between 10 and 15 minutes.

"In general, even those who had deeper scars seemed to be pleased with the results," said study author Dr. Jeremy A. Brauer, a dermatologist at the Laser & Skin Surgery Center of New York.

The participants' scars improved by 25 to 50 percent one month after the last treatment, and the improvement was maintained after three months, as shown in photos taken before and after the treatment, the researchers said.

The patients reported that they were satisfied or very satisfied with the results of the treatment, according to the study, which was paid for in part by Cynosure, the company that makes the laser. [7 Beauty Trends that Are Bad for Your Health]

Cynosure participated in designing the study, but the company did not conduct the research or collect, manage, analyze or interpret the data, according to the study. Brauer and his co-author on the study, Dr. Roy G. Geronemus, reported receiving money from Cynosure/Palomar Medical Technologies, Inc. Geronemus also serves on Cynosure's medical advisory board, according to the disclosures in the study.

Currently, the gold standard for treating deep-seated acne scarring is a device called a fractional ablative laser, which is harsher on the skin than the laser tested in the new study. After procedures using the fractional ablative laser, it takes people about a month to heal, Brauer said.

Both lasers are effective for acne-scarring treatment, but which one is a better choice for any person depends on the patient, his or her skin type, the type of scarring the patient has, and the individual's preferences regarding preparation for treatment and healing time, Brauer said. The fractional ablative laser actually removes parts of skin, which the other laser does not. When the laser tested in the study is used, the healing process takes less time, compared with the fractional ablative laser, he said.

"For someone who cannot afford much downtime or who wants a 'quicker treatment' and doesn't mind coming more frequently for multiple sessions, the picosecond laser is a great option," Brauer said. "For someone who has more-pronounced scarring, does not mind the downtime or does not want to have multiple treatments, the fractional ablative laser is a great choice."

The fractional ablative laser costs significantly more per treatment than the picosecond pulse duration laser treatment, Brauer said."However, in general, one would expect to perform fewer fractional ablative treatments [to get comparable results], so over time the total cost may be similar," he added.

The researchers discovered by accident that the picosecond pulse duration laser had the potential to treat acne scarring. This occurred when they were conducting a separate trial to test the laser as a tool to remove tattoos. The investigators noticed that one patient's stretch marks and scars improved while the researchers were removing her tattoo, so they decided to see how the treatment would work on acne scars, said Brauer.

The laser has already been approved for tattoo removal, and now the company that makes the device has submitted it for approval with the FDA to treat acne scars, Brauer said.

With laser use in general, patients have to be aware of the potential for scarring and change of skin pigment, Brauer said. In the new study, the researchers did not observe any worsening of the participants' scarring, and instead saw an improvement in the patients' skin texture and pigmentation, he said, describing the laser as "extremely safe."

The side effects of the treatment were redness and swelling that lasted from a few hours to two days after each application, according to the study. The participants rated the pain of the treatment as an average of 3 on a scale from 0 to 10, Brauer said. One participant in the study requested anesthesia before treatment.

The new study was published Wednesday (Nov. 19) in the journal JAMA Dermatology.

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