Laser advances in the treatment of burn and traumatic scars.

The realm of scar management is constantly changing. Many factors need to be considered when developing a comprehensive treatment plan, including the nature of the scar and the patient. Scar characteristics can be divided by color, scar type and thickness, and body location. Topical and intralesional agents and light- and laserbased treatments can be used to revitalize and restore damaged skin in atrophic and hypertrophic scars. The most commonly used lasers are the pulsed-dye laser (PDL) and fractional lasers. Ideally, a combination approach using topical and intralesional medications along with pulsed-dye laser and a fractional laser should be considered in all patients wishing to undergo treatment of their hypertrophic and atrophic scars. Keloidal scars tend to be resistant to standard therapy so other modalities should be considered.

Laser Safety in Isotretinoin Use: A Survey of Expert Opinion and Practice.

BACKGROUND: Reports of poor wound healing in the setting of isotretinoin treatment have created a conservative standard of care in which laser and phototherapy treatment of patients receiving isotretinoin is relatively contraindicated. OBJECTIVE: A survey of 220 nationally recognized experts in cutaneous laser surgery was conducted to evaluate physician experience and opinion pertaining to laser and light procedures in patients treated with isotretinoin, including perceived risk and actual complications. RESULTS: There was a 42% response rate. Seventy-six percent of respondents have never seen in their own clinical practices any cases of complications arising in patients treated with laser while receiving isotretinoin or within 6 months of completing a course of therapy. Almost half of respondents have treated patients in this subpopulation with laser, although only a small minority have done so with ablative devices. Common concerns among respondents regarding isotretinoin patients are the risks of poor wound healing and scarring, but the most often reported concern is medicolegal risk (74%). CONCLUSION: It would seem that the risk of performing laser procedures on patients receiving isotretinoin or having recently completed a course, as estimated and observed by cutaneous laser experts, is lower than the currently perceived risk among the general medical community.

Treatment of purpura with lasers and light sources.

The potential for bruising is a frequent concern for patients undergoing minimally invasive procedures, particularly injection-based soft tissue fillers and botulinum toxin type A. Decreasing the risk of this side effect with good technique and careful patient selection is key, but interventions that quicken the resolution of bruising are also helpful. Many practitioners have employed the theory of selective photothermolysis, using laser and light devices, to target hemoglobin and its breakdown products to speed time to bruise resolution. 585-595 nm pulsed dye, pulsed 532 nm and 1064 nm long-pulsed neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers and intense pulsed light may be utilized with best results achieved when treatment is performed 1-2 days after the appearance of purpura. Specific therapy recommendations, side effects and contraindications will be addressed in this review.

Botulinum toxin and the facial feedback hypothesis: can looking better make you feel happier?

The facial feedback hypothesis suggests that muscular manipulations which result in more positive facial expressions may lead to more positive emotional states in affected individuals. In this essay, we hypothesize that the injection of botulinum toxin for upper face dynamic creases might induce positive emotional states by reducing the ability to frown and create other negative facial expressions. The use of botulinum toxin to pharmacologically alter upper face muscular expressiveness may curtail the appearance of negative emotions, most notably anger, but also fear and sadness. This occurs via the relaxation of the corrugator supercilii and the procerus, which are responsible for brow furrowing, and to a lesser extent, because of the relaxation of the frontalis. Concurrently, botulinum toxin may dampen some positive expressions like the true smile, which requires activity of the orbicularis oculi, a muscle also relaxed after toxin injections. On balance, the evidence suggests that botulinum toxin injections for upper face dynamic creases may reduce negative facial expressions more than they reduce positive facial expressions. Based on the facial feedback hypothesis, this net change in facial expression may potentially have the secondary effect of reducing the internal experience of negative emotions, thus making patients feel less angry, sad, and fearful.

The spectrum of laser skin resurfacing: nonablative, fractional, and ablative laser resurfacing.

UNLABELLED: The drive to attain cosmetic facial enhancement with minimal risk and rapid recovery has inspired the field of nonsurgical skin rejuvenation. Laser resurfacing was introduced in the 1980s with continuous wave carbon dioxide (CO(2)) lasers; however, because of a high rate of side effects, including scarring, short-pulse, high-peak power, and rapidly scanned, focused-beam CO(2) lasers and normal-mode erbium-doped yttrium aluminium garnet lasers were developed, which remove skin in a precisely controlled manner. The prolonged 2-week recovery time and small but significant complication risk prompted the development of non-ablative and, more recently, fractional resurfacing in order to minimize risk and shorten recovery times. Nonablative resurfacing produces dermal thermal injury to improve rhytides and photodamage while preserving the epidermis. Fractional resurfacing thermally ablates microscopic columns of epidermal and dermal tissue in regularly spaced arrays over a fraction of the skin surface. This intermediate approach increases efficacy as compared to nonablative resurfacing, but with faster recovery as compared to ablative resurfacing. Neither nonablative nor fractional resurfacing produces results comparable to ablative laser skin resurfacing, but both have become much more popular than the latter because the risks of treatment are limited in the face of acceptable improvement. LEARNING OBJECTIVES: At the completion of this learning activity, participants should be familiar with the spectrum of lasers and light technologies available for skin resurfacing, published studies of safety and efficacy, indications, methodologies, side effects, complications, and management.

Comparison of stacked pulses versus double-pass treatments of facial acne with a 1,450-nm laser.

BACKGROUND: Although effective as a monotherapy for the treatment of inflammatory acne, the 1,450-nm diode laser is associated with considerable pain at higher fluences. MATERIALS AND METHODS: Eleven subjects were treated with a 1,450-nm diode laser in a split-face bilateral paired acne study. One-half of the face received a single-pass consisting of stacked double pulses. The other side received a double-pass treatment of single pulses. Settings were 11 J/cm(2) or lower as tolerated with appropriate dynamic cooling device (range 25-35). RESULTS: The mean pain rating was 5.33 on a 0 to 10 scale on the stacked-pulse treatment side and 5.12 on the double-pass side. Blinded reduction in mean acne lesion counts were 57.6% and 49.8% reduction, respectively. An overall acne scar improvement was seen in 83% of subjects with acne scarring. Transient hyperpigmentation occurred in two patients on the stacked pulse side and completely resolved without sequelae. CONCLUSIONS: The pulsed 1,450-nm diode laser can be used at lower fluences that elicit less discomfort yet effectively improve inflammatory acne. Stacking pulses appears to render a slightly higher efficacy than the multipass technique. Single-pulse, multiple-pass treatments may have a lower risk of cryogen-induced transient hyperpigmentation compared to standard high fluence techniques.

A split-face comparison study of pulsed 532-nm KTP laser and 595-nm pulsed dye laser in the treatment of facial telangiectasias and diffuse telangiectatic facial erythema.

BACKGROUND AND OBJECTIVES: Pulsed 595 nm and 532 nm lasers can effectively diminish or eliminate facial telangiectasia. We performed a split-face, single-blind, controlled, comparison study in an effort to determine their individual and comparative efficacy. STUDY DESIGN/MATERIALS AND METHODS: Fifteen patients were treated using a 595-nm PDL on one side of the face and a pulsed 532-nm potassium-titanyl-phosphate (KTP) laser on the other. Each subject was evaluated at 3 weeks after three treatments. RESULTS: Both devices improved telangiectasia. The 532-nm device, however, was at least as effective or more effective than the 595-nm laser in all subjects. On average, the KTP laser achieved 62% clearing after the first treatment and 85% clearing 3 weeks after the third treatment, compared to 49% and 75% for the PDL, respectively. Seventy-nine percent of KTP laser-treated patients continued to have swelling for greater than 1 day versus 71% of PDL-treated patients. Of those patients who noted persistent erythema for at least 1 day after treatment, 58% noted more erythema on the KTP laser-treated side compared to 8% on the PDL-treated side. CONCLUSIONS: Both the 595-nm and the 532-nm pulsed lasers are highly effective in the treatment of facial telangiectasia and redness. The 532-nm KTP laser appears to be more effective but causes more swelling and erythema.

Evaluation of plasma skin regeneration technology in low-energy full-facial rejuvenation.

OBJECTIVE: To evaluate the use of multiple, low-energy, full-face plasma skin regeneration treatments. DESIGN: Plasma skin regeneration delivers energy to the skin through plasma pulses induced by passing radiofrequency into nitrogen gas. Single-treatment, high-energy, 1-pass treatments have been demonstrated to achieve good results with an excellent safety profile. Eight volunteers underwent full-face treatments every 3 weeks, for a total of 3 treatments, using energy settings of 1.2 to 1.8 J. Before each subsequent treatment, the quality of regenerated epidermis, the degree of downtime, and erythema were recorded. Full-thickness skin biopsy specimens were obtained from 6 patients before treatment and 90 days following the last treatment. Patients were seen for follow-up 4 days after each treatment and 30 and 90 days after the third treatment. RESULTS: Three months after treatment, investigators found a 37% reduction in facial rhytids and study participants noted a 68% improvement in overall facial appearance. Reepithelialization was complete in 4 days. Patients assessed erythema to persist an average of 6 days after treatment. Epidermal regeneration from the first treatment was longer than from the following treatments (9 vs 4 and 5 days, respectively). One patient developed localized hyperpigmentation after the first treatment, which resolved by follow-up at day 30. No scarring or hypopigmentation occurred. A histologic evaluation 3 months after treatment revealed a band of new collagen at the dermoepidermal junction with less dense elastin in the upper dermis. The mean depth of new collagen was 72.3 mum. CONCLUSIONS: Plasma skin regeneration using the multiple low-energy treatment technique allows significant successful treatment of photodamaged facial skin with minimal downtime. Results are comparable to a single high-energy treatment, but with less healing time.

Clinical effect of a single pulsed dye laser treatment of fresh surgical scars: randomized controlled trial.

BACKGROUND: Pulsed dye laser has been used to decrease erythema and telangiectasia associated with scars, including surgical scars. There is limited evidence indicating improved surgical scar appearance if pulsed dye laser treatments are commenced immediately at the time of suture removal. OBJECTIVE: To determine whether a single one-pass pulsed dye laser treatment at the time of suture removal can improve the appearance of surgical scars. METHODS: Randomized controlled trial enrolling 20 patients (complete data for 17 patients) at two geographic sites, with blinded ratings of pre- and post-treatment photographs obtained at various time points. Included patients underwent elliptical excision for atypical nevi of the trunk and/or extremities, with at least one resulting scar of at least 5 cm in length or two scars of at least 2.5 cm in length. For each patient, each scar or half-scar (if a larger scar was used) was randomized to treatment or control groups. Treatment scars received a single one-pass treatment with a 595 nm pulsed dye laser (Vbeam, Candela Corporation, Wayland, MA, USA) at the time of suture removal (ie, 2 weeks after excision) at the following parameters: 7 J/cm2 fluence, 7 mm spot size, 1.5-millisecond pulse duration, and 30-millisecond spray, 20-millisecond delay of dynamic cooling. The treatment area included 1 cm on either side of the scar, and the round laser spots were overlapped 10%. Control scars were not treated with laser. RESULTS: Immediate purpura was induced from the laser treatment Six weeks after laser treatment, no significant difference was found in the clinical appearance of surgical scars treated with a single pulsed dye laser treatment on suture removal day versus those surgical scars not treated with laser. Parameters on which no significant difference was found included visibility of incision, erythema, hyperpigmentation, hypopigmentation, induration, and atrophy. Both sets of scars improved over time. CONCLUSIONS: A single pulsed dye laser treatment at the time of suture removal does not appear to have a beneficial effect on clinical scar appearance. The point of minimal benefit for such laser treatments may lie somewhere between one and three treatments.

Low-level laser therapy for wound healing: mechanism and efficacy.

BACKGROUND: Given the recent interest in light-emitting diode (LED) photomodulation and minimally invasive nonablative laser therapies, it is timely to investigate reports that low-level laser therapy (LLLT) may have utility in wound healing. OBJECTIVES: To critically evaluate reported in vitro models and in vivo animal and human studies and to assess the qualitative and quantitative sufficiency of evidence for the efficacy of LLLT in promoting wound healing. METHOD: Literature review, 1965 to 2003. RESULTS: In examining the effects of LLLT on cell cultures in vitro, some articles report an increase in cell proliferation and collagen production using specific and somewhat arbitrary laser settings with the helium neon (HeNe) and gallium arsenide lasers, but none of the available studies address the mechanism, whether photothermal, photochemical, or photomechanical, whereby LLLT may be exerting its effect. Some studies, especially those using HeNe lasers, report improvements in surgical wound healing in a rodent model; however, these results have not been duplicated in animals such as pigs, which have skin that more closely resembles that of humans. In humans, beneficial effects on superficial wound healing found in small case series have not been replicated in larger studies. CONCLUSION: To better understand the utility of LLLT in cutaneous wound healing, good clinical studies that correlate cellular effects and biologic processes are needed. Future studies should be well-controlled investigations with rational selection of lasers and treatment parameters. In the absence of such studies, the literature does not appear to support widespread use of LLLT in wound healing at this time. Although applications of high-energy (10-100 W) lasers are well established with significant supportive literature and widespread use, conflicting studies in the literature have limited low-level laser therapy (LLLT) use in the United States to investigational use only. Yet LLLT is used clinically in many other areas, including Canada, Europe, and Asia, for the treatment of various neurologic, chiropractic, dental, and dermatologic disorders. To understand this discrepancy, it is useful to review the studies on LLLT that have, to date, precluded Food and Drug Administration approval of many such technologies in the United States. The fundamental question is whether there is sufficient evidence to support the use of LLLT.

Clinical evaluation of enhanced nonablative skin rejuvenation using a combination of a 532 and a 1,064 nm laser.

BACKGROUND AND OBJECTIVES: Improvements in the physical signs of photoaging can be achieved by non-invasive laser resurfacing procedures. To evaluate the effectiveness and safety of the Nd:YAG 1,064 nm and KTP 532 nm lasers for non-invasive skin rejuvenation. STUDY DESIGN/PATIENTS AND METHODS: Subjects requesting non-invasive skin rejuvenation underwent two treatments with the 532 nm laser to one side of the face and with both lasers to the other side, followed by three treatments with the 1,064 nm laser to both sides. Skin characteristics were evaluated before, during, and up to 4 months after treatment. RESULTS: A >25% improvement in overall skin condition was observed for >30% of subjects at the 1 month follow-up and >40% of subjects at the 4 month follow-up. The greatest improvements were observed for visual dryness, roughness, and uneven pigmentation. No adverse events were reported. There was a trend for greater improvement in patients who received more 1,064 nm treatments but this was not statistically significant. CONCLUSIONS: The 532 nm KTP and 1,064 nm Nd: YAG lasers can be effectively and safely used for non-invasive skin rejuvenation.

Nonablative laser and light treatments: histology and tissue effects--a review.

BACKGROUND AND OBJECTIVES: Nonablative laser and light treatments have largely replaced ablative laser therapy in clinical use for the improvement of the visible signs of cutaneous photoaging, including rhytides, vascular lesions, and pigmentation. However, the mechanisms underlying the reported clinical efficacy of nonablative treatments are not well-understood. The purpose of this analysis is to critically evaluate what is known about histologic and tissue effects of nonablative laser therapy and suggest future directions for research. STUDY DESIGN/MATERIALS AND METHODS: This is a review of the English language literature pertaining to nonablative laser and light treatments available through MEDline (1995-2002), and unpublished reports presented at major national meetings. Only studies that included harvesting and analysis of tissue samples are included. RESULTS AND CONCLUSIONS: (a) Thermal injury to the dermis in association with epidermal cooling most likely affects the dermal vasculature, which initiates a cascade of inflammatory events that includes fibroblastic proliferation and apparent up-regulation of collagen expression; (b) There is no indication that nonablative treatments are harmful or able to induce skin cancer; (c) It is possible that the horizontally distributed collagen reported after nonablative treatments is a "microscar," an enlarged Grenz sone associated with repetitive photo-induced trauma; (d) Further research is needed to elucidate the biophysical mechanisms underlying nonablative treatment, as well as to distinguish the utility of different wavelengths on epidermal and dermal improvement.