Pulsed Dye Laser Therapy Research Articles

Membrane Attack Complex (MAC) Deposits in Skin Are Not Always Accompanied by S-Protein and Clusterin

Clusterin and S-protein bind to the membrane attack complex of complement (MAC) rendering it cytolytically inactive. Tissue necrosis as produced by pulsed tunable dye laser therapy (PTDL), and immune complex-related diseases such as lupus erythematosus, are accompanied by local accumulation of MAC. However, the mechanisms responsible for this accumulation might differ, and lead to deposition of MAC in different forms (cytolytically active or inactive). Biopsy specimens of lesional (22) and non-lesional (10) skin from 27 patients with a positive lupus band test (LBT) were studied using monoclonal antibodies against clusterin, S-protein, and MAC by immunofluorescence and immunoperoxidase. Identical studies were performed in normal and angiomatous skin specimens from three normal individuals before and after laser irradiation. MAC was present in 30 of 32 positive LBT skin biopsies. MAC was not only present in lesional (21 of 22) but also in non-lesional skin (nine of 10), although the intensity of staining appeared to be lower in the latter. Clusterin and S-protein co-localized with MAC, respectively, in 20 and 12 specimens, and were not found in the absence of MAC. In addition S-protein deposits were seen only in biopsies positive for clusterin. Deposits of clusterin and S-protein did not correlate with the presence or absence of lesions. After irradiation with PTDL, the immediate complement activation was accompanied by MAC deposits that were granular and clearly located on vascular endothelial cells. Clusterin and S-protein were not present on these cells. In summary, clusterin localizes with MAC along the skin dermal-epidermal junction in patients with a positive LBT, suggesting that it has a similar and possibly more important role than S-protein in regulating immune complex-mediated MAC formation. By contrast, clusterin and S-protein are not involved at the time of MAC formation in cells undergoing necrosis after PTDL therapy.

COMPARISON BETWEEN SEVOFLURANE AND HALOTHANE FOR PAEDIATRIC AMBULATORY ANAESTHESIA

We have compared the rapidity and quality of recovery after sevoflurane anaesthesia with those after halothane anaesthesia. Thirty unpremedicated paediatric outpatients undergoing pulsed-dye laser therapy for port-wine stains were allocated randomly to receive either halothane or sevoflurane anaesthesia. Each group received 60% nitrous oxide and 1.0-1.5 MAC of volatile agent in oxygen for approximately 40 min. Patients receiving sevoflurane exhibited more rapid emergence and a significantly shorter postoperative recovery time compared with those receiving halothane. No major adverse effects were encountered in each group. These results suggest that sevoflurane anaesthesia is preferable to halothane anaesthesia for paediatric ambulatory patients.

Capillary Hemangiomas and Treatment with the Flash Lamp-Pumped Pulsed Dye Laser

Strawberry, or capillary, hemangiomas are common vascular neoplasms, with an incidence of approximately 2.6% in neonates. They usually develop in the first few weeks of life, so that between 1 month and 1 year the incidence rises to between 8.7% and 10.1%. These lesions may grow quite large in the first year of life, and they may ulcerate or obstruct a vital organ or function. The great majority will spontaneously regress after the first year of life. Parents are often alarmed at the sight of these hemangiomas and need reassurance that the great majority will regress spontaneously. Treatments such as cryosurgery, irradiation, radium instillation, corticosteroid therapy, or surgical excision are often ineffective or cause significant morbidity. We describe 10 children with capillary hemangiomas treated with the flash lamp-pumped pulsed dye laser. The patients ranged in age from 7 weeks to 5.5 years at the beginning of laser therapy. The patients underwent 3.1 +/- 1 (mean +/- SD) laser treatments, with a mean regression of the lesions of 69.9% +/- 4.5%. All patients demonstrated some diminution in the size and color of their hemangiomas after the treatments, and there were no ill effects, such as ulceration, hemorrhage, infection, or scarring. There was no evidence of hyperpigmentation or hypopigmentation. Pulsed dye laser therapy should be considered as an option in the treatment of capillary hemangiomas, preferably prior to their full evolution. It is also a useful therapeutic approach in those hemangiomas that are slow to regress in older children.

Capillary hemangiomas and treatment with the flash lamp-pumped pulsed dye laser

• Strawberry, or capillary, hemangiomas are common vascular neoplasms, with an incidence of approximately 2.6% in neonates. They usually develop in the first few weeks of life, so that between 1 month and 1 year the incidence rises to between 8.7% and 10.1%. These lesions may grow quite large in the first year of life, and they may ulcerate or obstruct a vital organ or function. The great majority will spontaneously regress after the first year of life. Parents are often alarmed at the sight of these hemangiomas and need reassurance that the great majority will regress spontaneously. Treatments such as cryosurgery, irradiation, radium instillation, corticosteroid therapy, or surgical excision are often ineffective or cause significant morbidity. We describe 10 children with capillary hemangiomas treated with the flash lamp—pumped pulsed dye laser. The patients ranged in age from 7 weeks to 5.5 years at the beginning of laser therapy. The patients underwent 3.1 ± 1 (mean ± SD) laser treatments, with a mean regression of the lesions of 69.9% ±4.5%. All patients demonstrated some diminution in the size and color of their hemangiomas after the treatments, and there were no ill effects, such as ulceration, hemorrhage, infection, or scarring. There was no evidence of hyperpigmentation or hypopigmentation. Pulsed dye laser therapy should be considered as an option in the treatment of capillary hemangiomas, preferably prior to their full evolution. It is also a useful therapeutic approach in those hemangiomas that are slow to regress in older children. (<i>Arch Dermatol.</i>1991;127:202-205)

Effect of the Topical Anesthetic EMLA on the Efficacy of Pulsed Dye Laser Treatment of Port‐Wine Stains

EMLA cream (Eutectic Mixture of Local Anesthetics) is a new topical anesthetic composed of 25 mg lidocaine and 25 mg prilocaine in an oil-in-water emulsion cream. It has been found to be very effective for local anesthesia prior to venepuncture, minor surgical procedures, and pulsed dye laser (PDL) therapy for port-wine stains (PWS) in children. However, since EMLA may cause vasoconstriction of cutaneous vessels, we tried to determine whether pretreatment with EMLA decreases the efficacy of subsequent PDL treatment. We report eight patients between the ages of 4 and 32 years with PWS who received two test site treatments prior to PDL treatment. One site was pretreated with EMLA cream under occlusion for 60 minutes and then left unoccluded for 15 minutes prior to PDL test treatment. The other site, in the same area of the PWS and patient's body, was not pretreated with EMLA. The test sites were compared 6-8 weeks later to determine whether EMLA decreased the degree of lightening of the PWS compared to the non-EMLA-treated site. We conclude that EMLA is an effective topical anesthetic for PDL treatment of PWS and does not adversely affect the efficacy of the treatment.