Comparison of the effects of short- and long-pulse durations when using a 585-nm pulsed dye laser in the treatment of new surgical scars

Abstract

More than 70 million surgical procedures are performed annually in the USA with the majority involving a skin lesion and almost all individuals in their lifetime will have one or more surgical procedures resulting in scars. Patients and physicians alike are thereby motivated to improve the cosmetic outcome of scars. Prior studies have shown that the pulsed dye laser (PDL) is effective in improving the quality and appearance of the scar when using the 585-nm PDL immediately after the removal of sutures. Most published studies used a pulse duration of 450 micros, which along with the other study parameters, has led to an overall improvement of the scars. However, a pulse duration of 1.5 ms is also available when using the pulsed dye laser and it should theoretically cause fewer side-effects. To our knowledge, there are no other studies comparing the effectiveness of different pulse durations in the treatment of surgical scars starting on the day of suture removal. The purpose of this study is to compare the effect of different pulse durations (450 micros vs. 1.5 ms) in the treatments of postsurgical linear scars immediately after suture removal when using the 585-nm pulsed dye laser (PDL). Twenty non-hospitalized male and female patients (older than 18 years of age) with skin types I-IV and with postoperative linear scars measuring at least 2.1 cm were enrolled in this prospective study. Scars were randomly divided into three equal sections. The different fields were randomly chosen to receive treatment (two out of three fields) or remain as control (one field). The two fields chosen to be treated received treatment with the 585-nm PDL using a 7-mm spot size at 4.0 J. One of the treated sections was randomly selected to receive a pulse duration of 450 micros, and the other section to receive a 1.5-ms pulse. The remaining scar section was designated as control (no treatment). The three sections were mapped and recorded. The patient received treatment immediately after the sutures were removed from the wound and then monthly for 3 months. Evaluations were performed before each treatment and 1 month after the last treatment. The short-pulse and long-pulse 585-nm PDL-treated sections demonstrated a statistically significant overall average improvement of the VSS of 92 and 89%, respectively, compared to 67% for the control site (Fig. 1). Further, for individual parameters of the Vancouver scar scale (VSS), there were significant (p < 0.05) differences between control and treatment groups for all parameters, but there were no differences between the short- and long-pulse treatment groups for any parameter. Both short-pulse and long-pulse PDL are safe and effective in improving the quality and cosmetic appearance of surgical scars in skin type's I-IV starting on the day of suture removal with no significant difference between the two pulse durations.