秋田 浩孝

Background Monopolar radiofrequency (mRF) devices have been shown to be clinically effective for treating aging skin, but there are few histologic studies about the mechanisms. Objective To histologically analyze chronologic and quantitative change in collagens after mRF treatment to determine the mechanisms of the antiaging effect. Methods Five patients were enrolled in this study. Skin specimens were taken before and 1 and 3months after treatment. Immunostaining was performed to determine change in type I and III collagen levels and stem and other cell counts in skin layers. Results In all cases, both types of collagen significantly increased after irradiation in the dermis (p<.05), and their changes were noticed uniformly in all layers. No significant change was noticed in stem and other cell counts. Conclusions This study histologically demonstrated that type I and III collagen increased significantly in the dermis after mRF treatment. The amount of stem cells did not affect the increase in collagens.

A 16-year-old girl presented with a 9-year history of vesicles on the vulva. She had initially taken a wait-and-see approach, but required treatment because of bleeding. Histological examination of a biopsied vesicle revealed dilated lymph channels in the upper dermis, suggesting lymphangioma circumscriptum (LC). The challenge for this pathology has been to find a conservative treatment with low morbidity and better results than those reported for surgical excision, which has been the mainstay of therapy. In this case, LC of the vulva was successfully treated using a 10,600-nm CO2 laser and long-pulsed Nd:YAG laser. Use of the 10,600-nm CO2 laser and long-pulsed Nd:YAG laser appeared effective for treating LC. © 2014 S. Karger AG, Basel.

Background Quality-switched (QS) lasers are well-known effective treatment for removing solar lentigines. However, the high incidence of post-inflammatory hyperpigmentation (PIH) raises concern in darker skin types. This is the first study comparing efficacies and incidences of PIH in Asian skin with different degrees of irradiation between two QS lasers. Method In total, 355 solar lentigines in 193 cases, skin types III-V, were randomly divided into four groups. All cases received single laser treatment. Clinical results were evaluated after 4 weeks. Groups 1 and 3 were treated 'aggressively' with endpoints of very obvious immediate whitening (IW) of the lesion. Groups 2 and 4 were treated 'mildly' with endpoints of slight IW of the lesion. Groups 1 and 2 were irradiated with the QS ruby, and groups 3 and 4 with the QS frequency doubled Nd:YAG laser. Results There were no statistically significant differences in degrees of clearance among the four groups. However, PIH incidences were very different: 33.33%, 7.47%, 23.18% and 8.47% in groups 1, 2, 3 and 4 respectively. The difference between aggressively and mildly irradiated groups (1 and 3 vs. 2 and 4) was statistically significant (P &lt 0.001). However, there was no statistical difference between the two aggressively or the two mildly irradiated groups. There were no significant differences between skin types. Conclusion Aggressive irradiation using QS lasers resulted in a high PIH incidence, while having no advantage in efficacy. For darker skin types, mild irradiation reduces the PIH risk with no disadvantage in efficacy. © 2011 European Academy of Dermatology and Venereology.