K Negishi1, H Akita, S Tanaka, Y Yokoyama, S Wakamatsu, K Matsunaga. 1. Aoyama Institute of Women's Medicine, Tokyo Women's Medical University, Tokyo, Japan Department of Dermatology, Fujita Health University School of Medicine, Toyoake, Japan.
Abstract
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 < 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.
RCT Entities:
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 < 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.
Authors: Hye One Kim; Hye Ran Kim; Jin Cheol Kim; Seok Young Kang; Min Je Jung; Sung Eun Chang; Chun Wook Park; Bo Young Chung Journal: Medicina (Kaunas) Date: 2021-02-13 Impact factor: 2.430
Authors: Arielle N B Kauvar; Rongrong Sun; Jag Bhawan; Gaurav Singh; Nkem Ugonabo; Hao Feng; Kevin Schomacker Journal: Lasers Surg Med Date: 2021-08-17