Using a 2,940-Nm Er:YAG Laser for Traumatic Scars in the Early Posttraumatic Period

Keywords:laser, scar, medical, fibers,  Time:07-12-2015

INTRODUCTION

Ablative medical lasers fibers used for skin resurfacing, such as the CO2 and Er:YAG laser, can reduce various scars, but significant adverse effects limit their use, and patient downtime can be extensive. Owing to these potential risks, nonablative lasers have been developed as a safe alternative to ablative laser resurfacing, and have been reported to be effective and safe for scars. However, outcomes have remained unsatisfactory and require several treatments to achieve satisfactory efficacy [1,3]. Recently, the use of ablative and non-ablative lasers based on the fractional approach has become a novel strategy for the treatment of scars, and some authors have suggested that treatment with fractional lasers for various scars, such as postoperative, atrophic, and acne scars, has been demonstrated to safely improve the appearance of the scars [1]. However, few studies have been conducted on the efficacy of fractional laser treatment of traumatic scars during the early posttraumatic period. In this study, we investigated the efficacy and safety of ablative fractional resurfacing (AFR) using a 2,940-nm Er:YAG laser on traumatic scars after primary repair during the early posttraumatic period.

METHODS

Twelve patients (fifteen scars) of Fitzpatrick skin types III to V were enrolled. All had a history of laceration to the face and were repaired primarily by suturing on the day of trauma. Various types and colors of scars were presented; specific scar characteristics are described in Table 1. The mean age was 28 years, from 18 to 57 years. Patients with photosensitivity, pregnancy, active lactation, immunosuppression, keloid scarring, current anticoagulant treatment, isotretinoin usage, or ablative resurfacing within the previous year were excluded. Patients signed informed consent forms and granted permission for clinical photographs to be taken. Each patient was treated four times at 1-month intervals using the same parameters, and post-treatment following evaluations was performed 1 month later after the fourth treatment session. Laser therapy was started after at least 4 weeks of the primary repair. To relieve patient discomfort, a 5% lidocaine cream (EMLA, AstraZeneca, London, UK) with 20 minutes of occlusion, was applied before the treatment sessions, and faces were cleansed with 0.2% chlorohexidine gluconate. All patients were treated with a fractional ablative 2,940nm Er:YAG laser (LOTUSII, Laseroptek, Sungnam, Korea) at a setting of 1.29 J/cm2 and a spot diameter of 7 mm. Two laser passes of 400 mJ in short pulse mode (pulse duration 0.35 ms) and one pass of 800 mJ in long pulse mode (pulse duration 1 ms) were performed on scars during each treatment session. Clinical photographs were taken at baseline and 1 month after the final treatment. Figs. 1-4 show 4 cases of comparative pre- and post-treatment clinical photographs. Three types of assessment methods were used. First, 10 independent physicians scored the scars using the Vancouver Scar Scale (VSS) (Table 2). Second, evaluations at baseline and 1 month after final termination were conducted using pairs of comparative photographs by 10 independent physicians and 10 independent non-physicians using a 10-point scale, to assess clinical improvements in global cosmesis (using a 10-point scale; score 10, excellent improvement, score 1, poor improvement; a higher rating signifies a greater improvement). In addition, patient satisfaction was rated using a 4-point scale (grade 4: >75%, excellent improvement; grade 3: 51% to 75%, good improvement; grade 2: 26% to 50%, fair improvement; grade 1: 0% to 25%, poor improvement). Information on side effects and patient satisfaction were collected at each follow-up visit. Statistical analysis of comparisons between the pre- and post-treatment global cosmesis were performed with a Wilcoxon signed-rank test. SPSS ver. 17.0 statistical software (SPSS Inc., Chicago, IL, USA) was used. This study was approved by the Institutional Review Board of Gachon University Gil Hospital (GIRB 0004-2012).

RESULTS

All 12 patients completed the study. The average time between the day of trauma and the initiation of laser therapy was 45.7 days. At the conclusion of the four times of treatments with the ablative fractional Er:YAG laser, all treated portions of the scars showed improvements, as demonstrated by the VSS and the overall cosmetic scale evaluated by 10 blinded physicians, 10 blinded non-physicians, and the patients themselves. The mean VSS scores were 5.5 before treatment and 2.4 at 1 month after final treatment. After laser treatment, the mean VSS values decreased significantly (P<0.05) (Table 3). The follow-up results obtained by the 10 independent physicians and by the 10 independent non-physicians at 1 month after final treatment showed marked improvement that was evaluated with a Likert 10-point scale (Fig. 5). The mean grade of clinical improvement based on assessments of the clinical photographs by the 10 independent physicians was 7.0 and those by the 10 independent non-physicians was 6.9. In addition, 13.3% of the patients graded improvements as near total (>75%), 80.0% as marked (51% to 75%), and 6.7% as moderate improvements (26% to 50%) (Table 4). The mean grade of clinical improvement based on patients’ own satisfaction was 3.07.

DISCUSSION

The treatment of various scars with lasers is a relatively new concept that is gaining in popularity. Over the past decade, laser skin resurfacing with CO2 and Er:YAG lasers fibers has become a popular choice for the treatment of atrophic scars. However, although highly effective at re-contouring the skin and improving scar appearance, treatment with these ablative lasers has been associated with extended recovery periods, prolonged erythema, and other untoward side effects.