Comparison of the effectiveness of the pulsed dye laser 585 nm versus 595 nm in the treatment of new surgical scars

The aim of this study was to compare the effects of the pulsed-dye laser (PDL) at a wavelength of 585 nm with those at 595 nm in the treatment of post-surgical scars, starting on the day of suture removal. The study was a prospective, non-randomized, double-blind, controlled, clinical trial, set in an outpatient clinic. Fifteen outpatients with 21 post-operative scars at least 3 cm long were recruited, and 14 patients with 19 scars completed the study. Scars were divided into three equal portions. Each outer portion was randomly allocated to PDL at 585 nm or at 595 nm (3.5 J/cm², 450 μs, 10 mm spot size), and the center was an untreated control; treatment was composed of three laser sessions at 4-week intervals. A blinded examiner evaluated the three scar sections using the Vancouver scar scale for pigmentation, vascularity, pliability, and height. Cosmetic appearance was evaluated with a visual analog scale. Punch biopsies of three randomly selected scars were evaluated. Pigmentation: more scars after laser treatments were of normal color than in the control, but the difference was not statistically significant. Vascularity: after treatment, more scars had normal vascularity in all three groups than at baseline (P < 0.05); the largest increase was with a wavelength of 585 nm (10.5–94.7%), then 595 nm (15.8–78.9%), then control (5.2–36.6%). Pliability: there was more normal pliability in all three groups than at baseline (P < 0.05), with greater improvements in the laser-treated groups. Height: significantly more flat scars after 585 nm PDL (63.2%) than at baseline (21.1%) (P < 0.05). We observed a slight but non-significant decrease in the scar heights with 595 nm PDL in comparison with the control. Histology: after laser irradiation, the treated sections were more similar to a non-scarring process than the control. Cosmetic outcome: visual analog scales increased in all groups (P < 0.05), but the greatest increases were observed in the 585 nm and 595 nm laser-treated groups (50% and 60%, respectively) compared with controls (30%). There were significantly higher scores with the lasers than for the control (P < 0.001) at each visit after baseline. Both the 585 nm and 595 nm PDL treatments were effective in improving the appearance and normalizing the vascularity and pliability of post-operative scars. Both wavelengths improved the scars’ visual appearance more than controls. We found that 585 nm appears to be the preferred wavelength, as it substantially normalized the height in addition to the vascularity and pliability in a significant number of scars.     

Clinical pearl: the evaluation of the surface area of small pigmented lesions

The ability to calculate the surface area of small pigmented lesions is an important assessment tool, especially if one is suspicious for malignancy. Calculation of the surface area can be an arduous task if one does not have a standard technique. This article is in regards to the inexpensive and relatively easy technique of calculating the surface area of small pigmented lesions. This technique is a unique method, not described in the literature before, and may be utilized by any dermatologist at any level of experience. Our method is presented because the calculation of small pigmented lesions is an important tool to utilize, especially in cases of skin carcinoma. This technique can also be modified to calculate the surface area of much larger lesions and therefore may have a broad clinical application in the field of dermatology and cutaneous surgery.     

Photoepilation: a growing trend in laser-assisted cosmetic dermatology

Excess hair is an age-old condition plaguing both men and women alike, of all races. Conditions such as hirsutism or hypertrichosis, procedures that involve grafted donor sites, transsexual transformations from male to female, and genetics are all responsible for excess or unwanted hair. Previous options for people seeking to remove or lessen the presence of hair have either been painful or resulted in short-term hair removal. With the recent advent of laser technology, hair removal has been added to the many capabilities of the new generation nonablative lasers and light systems. Lasers are not yet a permanent solution for hair removal, but they are able to provide a safe, fast, and effective method of hair reduction.     

Topical imiquimod in conjunction with Nd:YAG laser for tattoo removal

The purpose of this study is to evaluate the efficacy of tattoo removal using topical imiquimod 5% cream in conjunction with the 1,064-nm Nd:YAG laser. This procedure for tattoo removal will be compared to laser treatment alone, which is the standard for cosmetic removal of tattoos. Previous studies have linked partial tattoo removal to imiquimod application in a guinea pig model. Methods: This was a small-sized, double-blinded, placebo-controlled trial with patients with Fitzpatrick skin types I-IV (light skin) who were 18–65 years of age. The patients were required to have had two tattoos of similar age and dark blue or black in color in areas that can be covered by clothing. There were four visits in total, with laser treatment and photography being performed on the first visit. Laser settings were with 1,064-nm Nd:YAG with a 10-ns pulse, 3-mm spot size, and 4 J of energy, a standard laser used for tattoo removal. During the second visit, tattoos were randomized and chosen to receive either the laser-imiquimod treatment course or laser-vehicle cream treatment. The patients returned 1 month after the completion of cream application (week #10) and 2 months after the completion of treatment with cream (week #14) for final evaluation and photographing. Results: Three patients were enrolled in this study. All of them are Fitzpatrick skin type IV. All of the patients were compliant with the drug application and have good tolerability with only mild pruritus without changing of vascularity or pigmentation. None of the patients had ulceration or scar development during the cream application. Conclusions: imiquimod plus laser therapy demonstrated a more favorable outcome when evaluated by the investigators or subjects. The mean scores for tattoo clearance from baseline to 2 months after completion of treatment with 5% imiquimod cream versus placebo cream were 4.3 versus 2.7 as rated by investigators and 4.7 versus 2.3 as rated by subjects. No textural changes were observed after therapy and were not shown to be different between the two groups. Further large-scale studies are important in developing a role for the use of imiqumod in laser-assisted tattoo removal.     

Comparison of short-pulsed and long-pulsed 532 nm lasers in the removal of freckles

The purpose of this study was to compare the efficacy and safety of the 532 nm long-pulsed laser (10 ms) with that of the 532 nm short-pulsed laser (10 ns) for freckle removal. Currently, the gold standard for treatment is the short-pulsed laser. Recently, several long-pulsed lasers have been introduced for both hair removal and the treatment of freckles. To our investigative team’s knowledge, no controlled experiments have been performed to compare the safety and efficacy of long-pulsed versus short-pulsed lasers for the treatment of freckles. This was a 4-week trial, and all patients had three freckles that were randomly allocated to be treated with short-pulse laser, long-pulse laser, or to receive no treatment (control). All patients had three freckles that were randomly selected to be treated with short-pulse 532 nm Medlite IV laser (10 n, 1 J/cm²), or long-pulse 532 nm Aura laser (10 ms, 1 J/cm²) or to remain as a control (no treatment). The laser treatment was only performed once, followed by a 1-day and a 1-month follow-up visit. Freckle size was determined by a novel surface area measurement technique that was created by our research staff. The study included 17 sets of freckles (three in each set). All of the lesions which received the short-pulsed laser treatment had immediate whitening of the lesions, which turned into dry scabs the next day. None of the freckles treated in the long-pulsed group or control group developed immediate whitening or scabs. No blisters or ulcers developed. The average pain score in the short-pulsed laser group was 2–3 out of 10, while it was 0 out of 10 in the long-pulsed laser group. All scabs that developed in the short-pulsed laser group fell off between days 6 and 12 (average 8 days). The outcome of this study verified the appropriate treatment of freckles. The study confirmed that when the same energy settings, short-pulsed laser is the more effective laser treatment regimen (when compared with the long-pulsed laser), with high tolerability and minimal side effects for patients with skin types I to IV.     

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

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 µs, 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 µs 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 µs, 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.