Improvement of Post-Surgical Scars with Laser Devices

Scars resulting from facial skin cancer surgery can be noticeable and distressing to patients. These scars are difficult to obscure with makeup. This case study describes the use of a pulsed dye laser (PDL) and ablative fractional CO2 laser to treat a patient’s post-surgical scars from a recent skin cancer surgery.

Our Patient

A 50-year-old white woman who underwent Mohs micrographic surgery to remove a basal cell carcinoma with mixed micronodular and infiltrative features and was then reconstructed with a large V-to-Y advancement flap repair. 

Treatment included using a PDL and ablative fractional CO2 laser sequentially for the improvement of post-surgical scars. Although scarring is a consequence of most cutaneous surgical interventions, untoward scarring can be physically and psychologically distressing to a patient. In addition, scars can be associated with pain, pruritus, discomfort and they can lead to contractures, free margin distortion or reduced range of motion in a joint.

Flashlamp-pumped 585-nm and 595-nm PDLs have been shown in multiple studies to be efficacious in the treatment of hypertrophic and keloid scars. Although the mechanism of action is still not completely worked out, PDLs appear to improve scar texture, color and pliability, as well as reduce symptomatology (including pain and pruritus).

CO2 laser emits light with a wavelength of 10,600 nm, which is preferentially absorbed by intracellular water. Use of this laser on the skin results in heating and vaporization of precise cutaneous layers. In addition to ablation, heat delivered to the surrounding tissue creates a zone of thermal damage. Subsequent to that, new collagen deposition along a more condensed collagen scaffolding leads to further resurfacing of skin. Fractional versions of CO2 lasers have then been developed to take advantage of this wavelength, yet to allow for islands of unaffected skin to provide a reservoir for faster tissue regeneration. This reduces or eliminates the risk of some of the most troublesome adverse effects associated with CO2 lasers — including prolonged downtime, persistent erythema and delayed hypopigmentation.

Treatment of Our Patient

At week 4 after surgery, 1 PDL treatment was performed.  At 6 weeks after surgery, (Figure 4) the first fractional CO2 laser resurfacing was performed, then subsequently repeated every 6 to 7 weeks for a total of 4 fractional CO2 sessions (Figures 1-8). 

Figures 1-8. Pre-operative and postoperative photos. At week 4 after surgery, 1 pulsed dye laser treatment was performed. At 6 weeks after surgery (Figure 4), the first fractional CO2 laser resurfacing was performed, then subsequently repeated every 6 to 7 weeks for a total of 4 fractional CO2 sessions (Figures 5,6,7). Photos courtesy_Joel L. Cohen, MD, FAAD, Denver, Colo.


Both PDLs and fractional CO2 lasers can be used in patients with hypertrophic or keloid scars and skin types I-III. Individuals with darker skin tones may be treated at lower fluences, but may experience post-inflammatory dyschromia. Timing appears to be important, as early intervention especially with fractional CO2 may lead to better outcomes.1-3 

A proper consent explaining the potential risks of laser therapy has to be obtained prior to the initiation of treatment. The skin should be cleansed thoroughly to ensure complete removal of makeup, concealers and sunscreen before each procedure.

For the treatment of hypertrophic and keloid scars, PDLs are usually used with a pulse duration of 0.45 to 1.5 ms and fluences ranging from 4.5 to 7.5 J/cm2, depending on the spot size. Concomitant cooling, typically achieved with cryogen spray or compressed air during laser light emission, helps to reduce peripheral damage and also improves tolerability. Although sub-purpuric doses may be used with PDLs, we find that the treatment often becomes less efficacious as compared to typical purpuric doses. In addition to transient purpura (which usually lasts 5 to 10 days), mild-to-moderate edema may be encountered, but is usually short-lived.

For the fractional CO2 laser, pre-treatment topical anesthesia seems to be preferred by some patients. If a scar is periorificial, antiviral agents can be considered to prevent a herpetic outbreak, although we tend to only use these for patients who have a recent history of recurrent cold sores or a strong history of multiple frequent outbreaks every year. In such cases, the regimen is usually started a few days before the laser session and then continued for about 5 days following the treatment. 

For each fractional CO2 treatment session, we use a fractional coverage of about 30%. With the Syneron-Candela CO2RE laser, preferred settings are: fusion mode (combination of deep and mid fractional settings), 30% coverage, ring size 117 to 129 and core 70. After the treatment, erythema, edema and oozing are common. These generally last from 4 to 5 days. Usually some pink blush to the treatment area can be apparent for up to 2 to 3 weeks. Post-treatment skincare is critical to reduce the risk of infection or contact dermatitis. Mild, fragrance-free, non-comedogenic cleansers and plain white petroleum jelly or Aquaphor are usually used until complete re-epithelialization.

Following laser treatment for scars, diligent sun protection is advised. Treatments are typically repeated every 4 to 8 weeks until significant improvement in scar texture and color is achieved — often requiring a minimum of 3 to 5 sessions. Patients who continue to note improvement may certainly consider additional treatments. The interval between sessions may have to be lengthened for those individuals with darker skin tones, where settings are often decreased by about 15% for the ablative laser treatments compared to patients with lighter skin.

Other standard treatments for hypertrophic or keloid scars can be used in conjunction with PDL and fractional CO2 laser — including intralesional agents like corticosteroids and 5-fluorouracil. However, if these are being performed on the same day as laser, we recommend that the injection be performed after laser treatment.

Clinical Pearls

Here are 4 clinical pearls to keep in mind when using PDL and fractional CO2 laser:

  1. Both PDL and fractional CO2 laser can be used for the improvement of hypertrophic and keloid scars, as well as recent post-surgical scars that demonstrate redness and texture variation compared to the adjacent skin. The combination of using both of these lasers may be synergistic — with the PDL initially decreasing redness and thickness and the ablative fractional laser then helping to improve texture and to camouflage scar lines.
  2. When treated with a PDL, scars often seem to respond better to purpuric doses for maximal improvement, though patients desiring little-to-no downtime may need sub-purpuric settings using longer pulse duration and lower fluences.
  3. Individuals with darker skin tones require lower fluences and longer treatment intervals with the fractional ablative laser sessions in order to try to avoid post-inflammatory dyschromia. Additionally, the cooling settings on the PDL may need to be changed to reduce the risk of cryogen-induced dyschromia.
  4. Combining therapies, such as intralesional injections and compression therapy, can increase the efficacy of the laser treatment of scars. 


Dr. Cohen is the director of AboutSkin Dermatology and DermSurgery in Colorado. His practice focuses on Mohs surgery and cosmetic dermatology. He is an associate clinical professor of dermatology at the University of Colorado.

Dr. Berlin is president of DFW Skin Surgery Center, PLLC, in Arlington, TX. He is also a clinical assistant professor of dermatology at the New Jersey Medical School in Newark, NJ.


Disclosure: Dr. Cohen has participated in a research project with Syneron-Candela. 

Dr. Berlin reports no relevant financial relationships.



1. Anderson RR, Donelan MB, Hivnor C, et al. Laser treatment of traumatic scars with an emphasis on ablative fractional laser resurfacing: consensus report. JAMA Dermatol. 2014;150(2):187-193.

2. Cohen JL. Minimizing skin cancer surgical scars using ablative fractional Er:YAG laser treatment. J Drugs Dermatol. 2013;12(10):1171-1173.

3. Lapidoth M, Halachmi S, Cohen S, Amitai DB. Fractional CO2 laser in the treatment of facial scars in children. Lasers Med Sci. 2014;29(2):855-857.