Effect of 1 064-nm Q-switched Nd:YAG laser on cell viability, protease activity and structures of Malassezia furfur / 中华皮肤科杂志

Objective:To investigate the effect of 1 064-nm Q-switched Nd:YAG laser at different energy settings on cell viability, protease activity and structures of Malassezia furfur. Methods:Cultured standard strains of Malassezia furfur were divided into several groups to be irradiated with 1 064-nm Q-switched Nd:YAG laser at different energies of 0 (control group) , 500, 600, 700, 800 and 900 mJ, respectively. Then, fungal suspensions in the above groups were inoculated onto the Leeming & Notman medium separately. After 7-day culture, the diameter and number of colonies were measured to evaluate the fungal cell viability, the protease activity was measured by using the whole-milk plate medium, and the ultrastructure of Malassezia furfur in each group was observed by transmission electron microscopy. One-way analysis of variance was used for comparisons among multiple groups, least significant difference- t test for multiple comparisons, and Pearson correlation analysis for analyzing correlations of laser energy with colony diameter, number and protease activity. Results:The colony diameter and number both significantly differed among the control group, 500-, 600-, 700-, 800- and 900-mJ groups (colony diameter: 4.05 ± 0.69, 3.76 ± 0.51, 3.28 ± 0.41, 3.09 ± 0.72, 2.54 ± 0.64 and 2.43 ± 0.41 mm, respectively; colony number: 4 787 ± 597, 4 287 ± 761, 1 879 ± 275, 1 082 ± 248 and 209 ± 42, 72 ± 31 colony-forming units, respectively; F = 14.83, 231.85, respectively, both P < 0.05) , and were significantly decreased in the 600-, 700-, 800- and 900-mJ groups compared with the control group (all P < 0.05) . The laser energy was negatively correlated with the colony diameter and number ( r = -0.67, -0.91, respectively, both P < 0.05) . The protease activity significantly differed among the control group, 500-, 700- and 900-mJ groups ( F = 346.60, P < 0.05) , and was significantly lower in the 700- and 900-mJ groups than in the control group (both P < 0.05) . There was a negative correlation between the laser energy and protease activity ( r = -0.94, P < 0.05) . Transmission electron microscopy showed intact fungal structures in the control group, relatively intact fungal structures in the 500-mJ group, and obviously damaged fungal structures in the 600- to 900-mJ groups, and the greater the laser energy, the more severely the fungal structures were damaged. Conclusion:The 1 064-nm Q-switched Nd:YAG laser could affect the cell viability of and protease activity in Malassezia furfur, and damage its structures.

A case of angiolymphoid hyperplasia with eosinophilia treated with Nd:YAG laser / 中华皮肤科杂志

A 38-year-old male patient presented with multiple papules on the scalp with itching and tingling for 3 years. Skin examination showed multiple millet- to soybean-sized red papules on the scalp. Histopathological examination showed epidermal hyperkeratosis, mildly thickened prickle cell layer, proliferation of a large number of capillaries in the dermis, and perivascular infiltration of closely distributed lymphocytes and scattered eosinophils. The blood vessels were lined by hyperplastic and hypertrophic endothelial cells, some of which projected into the vascular cavity. The patient was diagnosed with angiolymphoid hyperplasia with eosinophilia. After 1 session of Nd:YAG laser therapy, all the skin lesions were removed, and no obvious adverse reactions were observed. No relapse occurred during 5 months of follow up.

A case of angiolymphoid hyperplasia with eosinophilia treated with Nd:YAG laser / 中华皮肤科杂志

A 38-year-old male patient presented with multiple papules on the scalp with itching and tingling for 3 years. Skin examination showed multiple millet- to soybean-sized red papules on the scalp. Histopathological examination showed epidermal hyperkeratosis, mildly thickened prickle cell layer, proliferation of a large number of capillaries in the dermis, and perivascular infiltration of closely distributed lymphocytes and scattered eosinophils. The blood vessels were lined by hyperplastic and hypertrophic endothelial cells, some of which projected into the vascular cavity. The patient was diagnosed with angiolymphoid hyperplasia with eosinophilia. After 1 session of Nd:YAG laser therapy, all the skin lesions were removed, and no obvious adverse reactions were observed. No relapse occurred during 5 months of follow up.

Remoção de tatuagem com laser Q-switched NdYAG em população brasileira / Tattoo removal with Q-switched Nd: YAG laser in a Brazilian population

INTRODUÇÃO: Na prática da remoção de tatuagem, já foram utilizadas a dermo a brasão e a cirurgia. Atualmente, se utiliza o laser. O objetivo deste trabalho foi avaliar a remoção de tatuagens utilizando-se o laser Q-switched NdYAG. MÉTODO: Estudo retrospectivo, com pacientes tratados com laser Q-switched NdYAG. Foram coletados dados a partir de prontuários e fotos dos pacientes, e de contato por telefone ou e-mail. A análise estatística foi feita através da análise de distribuição, regressão multivariada e regressão logística. RESULTADOS: Foram avaliados 304 pacientes com média de idade de 29,8 anos (±7,86), sendo que 297 (97,69%) foram classificados como brancos (fotótipos I, II e III); destes, 270 (88,81%) haviam feito tatuagens profissionais. A tatuagem mais antiga tinha 360 meses e a mais recente, um mês, obtendo-se uma média de 64,56 meses (± 63,54). O tamanho das tatuagens foi, em média, de 12,92 cm, sendo preta a cor predominante, estando presente em 291(86,51%) tatuagens. A média de sessões por paciente foi de 3,77 sessões (±2,99) e o intervalo entre estas foi de 49,23 dias. Com isso, foi observado, pelo terapeuta, que 52,96% das tatuagens foram parcialmente removidas; 21,38%, não removidas; 86,51%, cicatrização normal; 8,55%, cicatriz hipertrófica, e 3,29%, queloide. Dos 304 pacientes, 26,64% (81) relataram estar satisfeitos e 58,88% (179) relataram estar parcialmente satisfeitos com o resultado. A hipocromia esteve presente em 33,55% (102) dos indivíduos. CONCLUSÕES: O laser Q-switched NdYAG é um método seguro e eficaz, apresentando bom grau de satisfação e poucos efeitos indesejáveis na remoção de tatuagem.

INTRODUCTION: Both dermabrasion and surgery have been used in the practice of tattoo removal. Currently, laser is also being used. The aim of this study is to evaluate tattoo removal with Q-switched Nd:YAG laser. METHOD: This is a retrospective study on patients treated by using Q-switched Nd:YAG laser. The data were collected from medical records and patient photographs, and through phone or e-mail contact. Statistical tests were done through the analysis of distribution, multivariate regression, and logistic regression. RESULTS: A total of 304 patients with an average age of 29.8 years (±7.86 years) were assessed. Of the total, 297 (97.69%) were classified as white (phototypes I, II, and III), 270 (88.81%) of whom had professional tattoos done. The oldest tattoo was 360 months old and the most recent was 1 month old, with an average of 64.56 months (±63.54 months). The tattoo size was, on average, 12.92 cm, with black being the predominant color (i.e., present in 291 [86.51%] tattoos). The average number of sessions per patient was 3.77 (±2.99), and the interval between sessions was 49.23 days. The therapist observed that 52.96% of the tattoos were partially removed, 21.38% were not removed, 86.51% showed normal healing, 8.55% developed a hypertrophic scar, and 3.29% developed a keloid. Of the 304 patients, 81 (26.64%) reported being satisfied and 179 (58.88%) reported being partially satisfied with the outcome. Hypochromia was present in 102 (33.55%) patients. CONCLUSIONS: Q-switched Nd:YAG laser is a safe and effective method for tattoo removal that results in a good degree of patient satisfaction and few undesirable effects.

Clinical Experience in the Treatment of Port-Wine Stains with Blebs

BACKGROUND: The current modality of choice for the treatment of Port-wine stains (PWS) is laser photocoagulation. Laser therapy for the treatment of PWS, especially with a pulsed dye laser (PDL), has been proven safe and effective; however, because penetration of the PDL is too shallow for an effective ablation of the blebs, treatment of blebbed PWS, using PDL, may be insufficient. OBJECTIVE: We demonstrated the clinical efficacy of a 1,064 nm long pulsed Nd:YAG laser with contact cooling device for blebbed PWS. METHODS: Twenty one patients with blebbed PWS (Fitzpatrick skin types II-V) underwent a treatment, using a 1,064 nm long pulsed Nd:YAG laser with a contact cooling device at 8-week intervals. Treatments were done using 5~6 mm spot sizes at 20~30 ms and 95~170 J/cm2. Laser parameters were adjusted in order to meet the needs of each individual patient's lesions. RESULTS: All subjects tolerated the treatments well, and showed clinical improvement from blebs. Of the 21 patients, 18 of them experienced either moderate or excellent response. CONCLUSION: Use of a 1,064 nm long pulsed Nd:YAG laser results in a greater depth of vascular coagulation. A 1,064 nm long pulsed Nd:YAG laser with contact cooling device may be regarded as a promising therapeutic option for the treatment of blebbed PWS.