Carbon dioxide skin resurfacing

“A blast of carbon dioxide could be better at erasing wrinkles than face creams,” the Daily Mail says. A form of laser surgery, carbon dioxide laser resurfacing, was first used in cosmetic surgery 20 years ago, but had fallen out of favour because it was linked with side effects. These included scarring and skin colour change. However, new research suggests that adverse effects clear within two years, “leaving patients with up to 50% fewer lines and wrinkles”, the newspaper reports.

This study relates the experience of professionals using carbon dioxide resurfacing. However, caution must be taken when drawing conclusions from these results. Only a small sample of 47 people have been followed over an average 2.8-year period, and complications of acne and change in skin colour were common. Many more people will need to be treated and followed for longer periods of time, and the effects will need to be compared with other treatments, in order to better establish the role that carbon dioxide laser resurfacing plays in the field of cosmetic surgery.

Where did the story come from?

Drs P. Daniel Ward and Shan R. Baker of Department of Otolaryngology (Head and Neck Surgery) at the University of Michigan, US, carried out this research. The authors are reported as providing funding for this research. It was published in the peer-reviewed medical journal Archives of Facial Plastic Surgery.

What kind of scientific study was this?

This was a case series in which the authors describe the experiences of patients who underwent carbon dioxide laser resurfacing with the aim of examining the long-term effects and complications. Carbon dioxide resurfacing works by vaporising water molecules in and around the skin cells. This causes heat damage to the skin cells and this promotes an increase in collagen production to repair the damage.

The researchers explain that in addition to structural changes in the skin, there is also a change in skin colour. The skin becomes either over-pigmented or loses pigmentation. Nearly all patients in previous studies had loss of pigmentation.

Dr Baker performed 62 procedures between December 1996 and December 2004 on either the face or eyelids. Pre-operative and post-operative photographs were obtained so that wrinkles could be graded before and after treatment, using a scale verified for scoring wrinkles after the use of injectable fillers.

The researchers gave the entire face a score using individual scores assigned to each of five facial subsites: the space between the eyebrows, around the eyes, the corners of the mouth, the upper lip and the (melolabial) fold between the mouth and cheek extending to the base of the nose. Improvement in wrinkle score was calculated by the “ratio of the difference between the pre-procedure and post-procedure scores and the pre-operative score”. All complications were recorded. General characteristics of the people who lost pigmentation of the skin were compared with those who did not, such as age and pre-operative wrinkle score.

What were the results of the study?

Complete data were available for 47 cases (42 women; five men) with an average age of 52, nearly all of whom had fair-to-medium skin tone (skin type 1, 2 or 3). The average follow-up was 2.3 years. In addition to laser resurfacing, many of the people had undergone additional procedures, such as microdermabrasion and brow-lift.

The average improvement in facial wrinkle score was 45% (95% CI 40.6 to 49.7%) with the same improvement seen when they looked at every subsite on the face. Twenty-one patients had no complications (45%) and 14 (30%) experienced acne, eight (17%) had over-pigmentation of the skin, and six (13%) had under-pigmentation One person experienced a skin infection, and one person had ectropion (outward rolling of the eyelid).

Of all patients, 70% were followed up to one year, and in the main, the only complications seen to persist were under-pigmentation (over-pigmentation persisted in one case), but these resolved after two years. None of the patients with follow-up of less than one year developed under-pigmentation.

There was no significant difference in age or pre-operative wrinkle score between those who did and those did not lose skin pigmentation. However, there was significantly greater wrinkle improvement (73.9%) in the patients who lost skin pigmentation compared with those who did not.

What interpretations did the researchers draw from these results?

The researchers say that their results show that carbon dioxide laser resurfacing is a safe and effective treatment that gives long-term improvement in the appearance of facial wrinkles – an average improvement of 45% compared with before treatment.

What does the NHS Knowledge Service make of this study?

Although this study is an accurate case series relating the experience of professionals using carbon dioxide resurfacing, caution must be taken when drawing implications from these results for a number of reasons:

• This case series is from a relatively small number of only 47 people. As such, it cannot give reliable figures for the percentage improvement in wrinkles or of the rate of complications from this treatment. Figures may be very different in a much larger series of people.
• The wrinkle scoring system has been verified when using injectable fillers, and although it may be the most reliable method at the current time, it relies upon the clinician’s objective judgement of photographs. This means there may be some variability between one person’s assessment and another. 
• It is also unclear from this report whether any measure of patient satisfaction has been considered. In the field of cosmetic surgery, patient satisfaction in the change in their appearance may be one of the most important outcomes.
• Potential patients must be aware of the complications of treatment, which were relatively common in this small sample, and may be greater if more cases were considered. For example, this series contained few people with dark skin tones. As the researchers acknowledge, loss of skin pigmentation is a fairly common adverse effect of treatment and therefore the effects of this outcome in people with dark skin tones must be considered.
• Follow-up at the current time has been relatively short, and it would be important to see that there were no adverse complications many years after treatment.

Many more cases will need to be treated and followed and the effects compared with other treatments in order to better establish the role that carbon dioxide laser resurfacing plays in the field of cosmetic surgery.