Laser treatment of pigmented lesions and tattoos.

Benign pigmented lesions and tattoos are often very responsive to laser treatment. The chromophore in most cases is melanin, although other endogenous and exogenous pigments can be targeted. The chromophore and its distribution in the skin, as well as the underlying biological processes, all help determine the best laser, if any, for a given pigmented lesion. Epidermal lesions respond well to shorter wavelengths (up to 755 nm), whereas for deeper lesions, 694 nm or longer are typically used. The 1,064-nm Nd:YAG laser is best for treating darker skinned individuals. Multicolored tattoos may need several wavelengths to best target individual ink colors.

The pulsed dye laser for cutaneous vascular and nonvascular lesions.

The pulsed dye laser was originally developed for the treatment of vascular lesions, especially hemangiomas and port-wine stains. The central concept of pulsed-dye laser is to preserving the epidermis by allowing hemoglobin to be more precisely targeted within lesions. More recently, the pulsed dye laser has also been used in the treatment of a wide spectrum of nonvascular lesions. Because of its safety profile, and its selectivity in targeting lesions, therapists can comfortably treat a wide variety of lesions in all age groups and anatomic sites.

Laser treatment of port-wine stains and hemangiomas.

Since their discovery, lasers have truly advanced and broadened our options for the treatment of port-wine stains and hemangiomas. It is a blending of many sciences and much effort that allows us the opportunity today to selectively treat these vascular processes with relative effectiveness and significant safety. Ongoing study and development continue to offer hope on increasing benefit for our patients. Laser systems with variable wavelengths, pulse durations, and delivery methods will help accommodate the diversity of various port-wine stains and hemangiomas that are encountered in medicine.

Bowen's disease of the distal digit. Outcome of treatment with carbon dioxide laser vaporization.

BACKGROUND: Bowen's disease (squamous cell carcinoma in situ) is an intraepithelial neoplasm that can transform into invasive squamous cell carcinoma. The preferred method of eradication for Bowen's disease is surgical excision. However, when Bowen's disease occurs on the digit, surgical removal can lead to scar contracture and loss of use of the finger. OBJECTIVE: To assess the utility of carbon dioxide (CO2) laser vaporization in eradicating Bowen's disease of the finger while maintaining the full range of motion and use of the digit. METHODS: Five patients were treated with CO2 laser vaporization for Bowen's disease of the digit. Patients were followed postoperatively for recurrence, clinical appearance, especially for scar formation, and function of the involved joints over a 6-month to 3-year period. RESULTS: Four of five patients had no recurrence. Healing resulted in only modest alterations in the cosmetic appearance in comparison with the surrounding untreated skin. Posttreatment biopsy showed slight thinning of the epidermis and mild fibroplagia limited to the papillary dermis. Patients reported only mild post-procedure discomfort and no patients had any loss of function of the digit. CONCLUSIONS: CO2 laser vaporization may be a safe and effective means by which to eradicate Bowen's disease of the finger without the risk of scar contracture and loss of function of the digit.

Psoriasis response to the pulsed dye laser.

BACKGROUND AND OBJECTIVE: In psoriasis the blood vessels are enlarged and dilated. These vessels, the psoriatic microvasculature, have been implicated as participating in the pathogenesis of psoriasis. The purpose of this preliminary study was to use the flash-lamp-pumped pulsed dye laser, which selectively damages dermal vessels, to treat psoriatic plaques and to evaluate the role of the vasculature in the therapeutic response. MATERIALS AND METHODS: Ten patients with psoriasis were treated with the pulsed dye laser on single, stable psoriasis plaques. Treatments varied between one and three times, and the lesional response was graded using a scale for erythema, scaling, and infiltration. RESULTS: Six of 10 patients experienced a beneficial clinical effect after therapy. The psoriasis severity scale in these patients was reduced to 2.2 +/- 1.3 compared with a 7.2 +/- 1.7 grade for control areas. The plaques readily developed crusting with therapy, with one leg lesion healing with atrophy. Histopathology in three patients immediately after therapy showed no epidermal damage. One week after laser therapy, the necrotic former epidermis was apparent in superficial crusting. Epidermal thinning and regeneration was seen without any signs of psoriasis. CONCLUSIONS: Pulsed dye laser therapy may improve plaque psoriasis. This improvement may be related to the role the microvasculature plays in psoriasis.

Cryoglobulinemia and cutaneous leukocytoclastic vasculitis associated with hepatitis C virus infection.

Hepatitis C virus infection is a frequent cause of non-A, non-B hepatitis worldwide. Resultant morbidity is significant; chronic liver disease develops in 50% of infected persons. Since serologic testing has become available there have been several reports of cutaneous findings in association with hepatitis C virus infection, including vasculitis, cryoglobulinemia, urticaria, and lichen planus. We describe a patient with cryoglobulinemia, chronic cutaneous leukocytoclastic vasculitis, and hepatitis C virus infection. Hepatitis C virus infection should be included in the differential diagnosis of the causes of cryoglobulinemia and leukocytoclastic vasculitis.

Clinical efficacy of the pulsed dye laser in the treatment of vascular lesions.

BACKGROUND: Increasing the selectivity of laser-induced damage is an ongoing goal for the laser treatment of cutaneous lesions. The flashlamp-pumped pulsed dye laser has significantly participated and advanced this pursuit. This is especially true in its use for the treatment of cutaneous vascular lesions. OBJECTIVE: A review of the development and current use of this laser for the treatment of cutaneous vascular lesions will be presented. METHODS: The laser has been designed to limit laser energy absorption and damage to hemoglobin and the blood vessel. This has been done by setting the wavelength at 577 to 585 nm and the pulse duration at 360 to 450 microseconds. RESULTS: The therapeutic results have been beneficial for almost all types of superficial small vessel vascular lesions regardless of lesional anatomic site or patient age. These lesions include port-wine stains, telangiectasia, capillary hemangioma, and other angiomata and vascular ectasia. Deeper cutaneous vascular processes and lower extremity telangiectases have proven to be less responsive to therapy. The increased vascular selectivity has allowed for a dramatic decrease in adverse effects when compared to previously used laser systems. CONCLUSION: Based on many thousands of treatment sessions and follow-up evaluation, the pulsed dye laser appears to have the greatest margin of safety in the treatment of cutaneous vascular lesions, especially for the pediatric population.

Treatment of cutaneous hemangiomas by the flashlamp-pumped pulsed dye laser: prospective analysis.

Thirty-three cutaneous capillary and mixed hemangiomas in 24 patients were treated prospectively with the flashlamp-pumped pulsed dye laser. Patients ranged in age from 2 weeks to 7 months; the follow-up period was up to 22 months. Some patients received therapy until the lesion was almost clear or until the lesion failed to respond; others received treatment only until active capillary lesional proliferation abated. In the first group of patients, 18 of 25 lesions that were 3 mm or less in elevation lightened with therapy (93.9% +/- 4.6% in 4.1 +/- 1.6 treatment sessions) and flattened to 0.3 +/- 0.4 mm in thickness. The seven lesions that were 4 mm or more in thickness lightened 85.7% +/- 7.3% in 7.0 +/- 2.0 treatment sessions but showed less diminution in thickness (to 3.4 +/- 3.6 mm; p less than 0.01). The second group of patients, who received therapy until proliferation ceased, required just one to three therapeutic sessions. Three of the four lesions that showed residual atrophy were 4 mm or greater in thickness; the fourth lesion was ulcerated on presentation. None of the lesions had residual induration or scarring. We conclude that the flashlamp-pumped pulsed dye laser may successfully prevent enlargement and promote involution of capillary hemangiomas with minimal adverse effects. Therapy is most appropriate for patients with hemangiomas at sites of potential functional impairment, of maceration or ulceration, and of significant cosmetic disfigurement. Therapy should be initiated as early as possible, when lesions are relatively flat, for optimal results.

Dermatologic laser surgery.

The laser is becoming an increasingly important surgical and medical instrument in the field of dermatology. Developments in the areas of laser technology and application have significantly broadened its clinical use over the past several years. These rapid changes and advances in the use of the laser for cutaneous processes may make it difficult for the physician to maintain a current base of knowledge in this area. Relevant laser systems and their clinical applications are presented and discussed, as are investigational laser systems, which may be of importance for the future. This will allow the dermatologic surgeon the opportunity to update concepts and evaluate the various laser systems and their cutaneous applications.

Pearly penile papules: treatment with the carbon dioxide laser.

Pearly penile papules are frequently occurring lesions located over the corona and sulcus of the penis. They are asymptomatic and are considered to be acral angiofibromas. Some individuals, disturbed by their presence, request removal of the lesions. Even after patients are assured of the benign nature of the process and its relatively high incidence, prominent lesional involvement may still cause significant psychological distress. Two patients with pearly penile papules have been successfully treated with the carbon dioxide laser. A review of the literature and description of treated cases are presented.

The treatment of port-wine stains by the pulsed dye laser. Analysis of pulse duration and long-term therapy.

A flashlamp-pumped pulsed dye laser at 577 nm was evaluated in the treatment of port-wine stains. The degree of lesional lightening was compared following laser exposure with pulse durations of 20 and 360 microseconds. In addition, lesional therapy using the 360-microseconds pulse duration was evaluated for lightening and side effects following long-term patient observation and after repeated treatments of the same site. A total of 52 patients with port-wine stain were treated; their average age was 29 years, with eight patients less than 18 years, of whom 29 had comparative test site placement for the different pulse durations. Of these 29 patients, 25 demonstrated greater lightening at the 360-microseconds pulse duration test site. All 52 patients proceeded to receive full treatment placement with the 360-microseconds pulse duration, which resulted in an overall lightening of 42% after the initial treatment and 68% after re-treatment sessions. Forty-four percent of the patients had equal to or greater than 75% lesional lightening. Pretreatment anesthesia was unnecessary and only minimum posttreatment care was required. Mild adverse effects of epidermal change, depression, or pigmentary change appeared in only four cases and was limited to less than a 2% area in each of these lesions. These side effects did not recur when the lesions were re-treated at lower energy dosages. No posttreatment sclerosis or scarring appeared, even after multiple retreatment sessions to the same area, regardless of the anatomic location, color of the lesion, or age of the patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulsed dye laser (577 nm) treatment of portwine stains: ultrastructural evidence of neovascularization and mast cell degranulation in healed lesions.

Portwine stains were examined before, immediately after, and 1 yr after successful clearance by a pulsed dye laser (577 nm) using ultrastructural techniques. Dilated vascular channels and mast cell hypoplasia characterized lesional skin before treatment. Immediately after treatment, widespread selective vessel necrosis, similar to changes previously described, was observed. One year after laser irradiation, the abnormally ectatic portwine stain vessels had been replaced by small venules and arterioles, similar in number and diameter to blood vessels in normal skin; the only difference noted was that these new vessels were surrounded by easily identifiable mast cells. Many of these mast cells exhibited evidence of activation and degranulation. We conclude that mast cells may play an important role in the neovascularization of portwine stains treated by 577-nm dye laser irradiation.

Papillomavirus in the vapor of carbon dioxide laser-treated verrucae.

Vapor produced by the carbon dioxide laser during the vaporization of papillomavirus-infected verrucae was analyzed for viral DNA content. Two models were used for evaluation: an in vitro cutaneous bovine fibropapilloma and an in vivo human verruca model. Four bovine fibropapillomas were exposed to various laser parameters with power densities of 38,200 to 130 W/cm2 and energy fluences of 3820 to 130 J/cm2. The generated vapor was collected in a chamber in line with a vacuum system. Hybridization with bovine papillomavirus DNA probes revealed intact bovine papillomavirus DNA for all power densities and energy fluences used. The laser vapor from seven patients undergoing carbon dioxide laser therapy for plantar or mosaic verrucae was also collected. Laser parameter settings were similar to those usually chosen for clinical tissue vaporization. Intact human papillomavirus DNA was present in the vapor from two of seven patients. These studies indicate that intact viral DNA is liberated into the air with the vapor of laser-treated verrucae. It would be prudent for all practitioners who use the laser in treating patients with viral infections or conditions associated with viruses to practice extreme care and safety throughout the laser procedure.

Treatment of resistant severe psoriasis with systemic cyclosporine.

Four patients with severe psoriasis have been treated with oral cyclosporine for 6 months. Two had generalized erythroderma and two had extensive plaque-type psoriasis; all had either become unresponsive to or were unable to use other accepted treatments. All four patients responded rapidly and were completely clear of psoriasis within 3 weeks of beginning therapy. Initial doses ranged from 7.5 to 8.5 mg/kg/day. Mild reversible nephrotoxicity occurred in the one patient whose cyclosporine trough level briefly exceeded 200 ng/ml. Cyclosporine may offer an alternative therapeutic modality in the management of erythrodermic or severe resistant plaque-type psoriasis. The effectiveness of cyclosporine in psoriasis underscores the putative role of cell-mediated immune factors in the pathogenesis of psoriasis.

Wound healing in porcine skin following low-output carbon dioxide laser irradiation of the incision.

Wound healing of scalpel incisions to the depth of adipose tissue closed with conventional methods was compared with closure by low-output carbon dioxide laser irradiation. In 3 Pitman-Moore minipigs wound healing was evaluated at intervals from 1 to 90 days by the following methods: clinical variables of wound healing; formation of the basement membrane components bullous pemphigoid antigen, laminin, and fibronectin; and histological evaluation of the regeneration of the epidermis, neovascularization, and elastin and collagen formation. There was no significant difference in healing between wounds closed by the various conventional methods and by the low-output carbon dioxide laser.