For example, enhanced lasers such as the CoolTouch CO2 (carbon dioxide) laser and recently approved Fraxel IV laser earned FDA approval because the devices have the same or similar wavelength and operating principles as previously approved devices.

Since a substantial portion of laser devices attain FDA approval based on the effectiveness of previously approved devices, how is the consumer to discern which laser is best for removing acne scarring?

Before we address that issue, another item makes reviewing medial studies of laser treatments for acne scars even more puzzling.

Thomas Rohrer, a dermatologic surgeon in private practice in Chestnut Hill, Massachusetts, elucidated this point in a Skin and Allergy News editorial. Dr. Rohrer used an example of how evaluators of patient improvement levels after laser treatments could not independently or unbiasedly concur on the level of improvement in the patient's skin.

For instance, in four separate studies, the same physician performed laser procedures on different groups of patients using the same type of laser. Yet, when study evaluators examined before and after images of the study participants, their opinions on the cosmetic improvements in the patient's skin varied enormously.

The laser treatment conundrum Dr. Rohrer's exposes is, "How could such varying results come from using the same device with the same technique, especially considering that the four studies were all performed by the same investigator?"

Dr. Rohrer proposes this inconsistency arises from the three categories of laser study evaluators. The the laser "enthusiasts" give the procedure the best scores. The "ambivalent" evaluators give scores in the middle range. And finally, the laser doubters give the lowest scores.

Regardless of the grave variables tainting laser studies, the number of treatments needed and the overall acne scarring improvement level do allow a means to rank cosmetic lasers. Here's how four competing lasers to treat acne scars compare.

#4 1,064-nm Nd:YAG Pulsed Light System

Treatments: 8 Improvement rating: 29.36%

Marketed names include PhotoSilk Laser

Last year, a study in Dermatologic Surgery tested the efficacy of the 1,064-nm Nd:YAG laser at removing acne scars. Nine patients received eight treatments for moderate to severe acne scarring. Three independent physicians rated the overall improvement level of acne scarring severity for the group at 29.36%.

# 3 1,320-nm Nd:YAG

Treatments: 5 Improvement rating: 40-60%

Marketed names include CoolTouch Laser

An investigation from the same journal featured eight patients with facial acne scars. The group received eight treatments with the 1,320-nm Nd:YAG laser. After five treatments, independent observes assessed the overall acne scarring improvement rate between 40-60 %.

# 2 1,450-nm diode laser

Marketed names include Smoothbeam Laser

In a split test comparison between the 1,450-nm laser and 1,320-nm laser at treating mild to moderate atrophic (indented, or lost skin tissue) acne scarring, the 1,450-nm laser demonstrated greater improvement in acne scarring.

#1 1,550-nm erbium-doped fiber laser

Treatments: 3 Improvement rating: 51-75%

Marketed names include Fraxel Laser Fraxel

This past March, a study in Dermatologic Surgery tested the 1,550-nm erbium-doped fiber laser on fifty-three patients with mild to moderate atrophic facial acne scars. After three treatments, two independent reviewers judged a 51-75% improvement in the scarring of 90% of the study participants.

Again, these ratings are based on the improvement levels patients coping with mild to severe acne scarring experienced after various laser treatments. As Dr. Rohrer explained, it is difficult to predict what your skin will look like after a laser treatment for acne scarring because many of the patient assessments during the studies were based on opinions of before and after photos.

To reduce the unpredictability surrounding laser correction of acne scars, ask your laser surgeon for before and after images of laser cosmetic procedures she has performed in the past months. Then judge the overall acne scarring improvement level for yourself.

Sources:

Alster, Tina; Elizabeth L Tanzi & Melissa Lazarus. The Use of Fractional Laser Photothermolysis for the Treatment of Atrophic Scars. Dermatologic Surgery; March 2007, vol 33, no 3, pp 295-299.

Lipper, Graeme M & Maritza Perez. Nonablative Acne Scar Reduction after a Series of Treatments with a Short-Pulsed 1,064-nm Neodymium:YAG Laser. Dermatologic Surgery; August 2006, vol 32, no 8, pp 998-1006.

Rohrer, Thomas E. Ethics in Cosmetic Laser Treatments. Skin and Allergy News; May 2007, vol 38, no 5, pp 14-15.

Sadick NS & AK Schecter. A Preliminary Study of Utilization of the 1320-nm Nd:YAG Laser for the Treatment of Acne Scarring. Dermatologic Surgery; July 2004, vol 30, no 7, pp 995-1000.

Tanzi, Elizabeth L & Tina S Alster. Comparison of a 1450-nm Diode Laser and a 1320-nm Nd:YAG Laser in the Treatment of Atrophic Facial Scars: A Prospective Clinical and Histologic Study. Dermatologic Surgery; February 2004, vol 30, no 2, pp 152-157.