Department of Dermatology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Lasers Surg Med. 2024 Sep;56(7):642-649. doi: 10.1002/lsm.23828. Epub 2024 Jul 29.
BACKGROUND/OBJECTIVE: Laser therapy has emerged as a widely favored treatment option for solar lentigines (SL). However, a significant challenge associated with this treatment, particularly among individuals with darker skin tones, is the notable risk of postinflammatory hyperpigmentation (PIH) induction. In response to these concerns, the authors conducted a prospective, self-controlled study to comprehensively evaluate the safety and effectiveness of 532-nm picosecond laser, both with and without a microlens array (MLA), for the management of SL in patients with Fitzpatrick skin types (FST) III-V.
Twenty-seven patients with FST III-V and bilateral SL on the face underwent randomized treatment. One side of the face was treated with a 532-nm picosecond laser coupled with an MLA, utilizing the fractional pigment toning (FPT) technique, while the other side received treatment without the MLA, following the conventional technique (CT). The FPT technique utilized a 9-mm spot size with a fluence of 0.47 J/cm for two passes covering 40% of the area. In contrast, the CT used a 4.5-mm handpiece with fluence ranging from 0.3 to 0.7 J/cm. Patients received a single treatment and were evaluated for pigment clearance, occurrence of PIH, and other adverse effects at 2 weeks, 1, 3, and 6 months posttreatment.
Twenty-seven participants completed the study protocol. Analysis of pigment clearance, measured via 3D photography, showed significant improvement from 2 weeks to 6 months posttreatment for both the FPT technique (p < 0.001) and CT (p = 0.004). PIH occurred in 64%, 80%, 96%, and 88% of cases on the CT side, compared to 8%, 32%, 36%, and 16% on the FPT technique side at 2 weeks, 1, 3, and 6 months posttreatment, respectively. The incidence of PIH was significantly lower on the FPT technique side compared to the CT side throughout the follow-up periods. Additionally, transient and mild hypopigmentation occurred in one participant (4%) on the FPT technique side and in five participants (20%) on the CT side. No other adverse effects were observed during the study.
The 532-nm picosecond laser emerges as a safe and efficacious treatment modality for SL in individuals with FST III-V. Particularly noteworthy is the efficacy of the FPT technique, which demonstrates comparable effectiveness while significantly reducing the incidence of PIH compared to the CT.
背景/目的：激光治疗已成为治疗太阳黑子（SL）的广泛首选治疗方法。然而，这种治疗方法的一个主要挑战是，尤其是对于肤色较深的个体，显著增加了炎症后色素沉着过度（PIH）的诱导风险。针对这些担忧，作者进行了一项前瞻性、自身对照研究，全面评估 532nm 皮秒激光联合和不联合微透镜阵列（MLA）治疗 FST III-V 患者 SL 的安全性和有效性。
27 名 FST III-V 患者，面部两侧均有 SL，进行随机治疗。一侧面部采用 532nm 皮秒激光联合 MLA，采用分数色素调谐（FPT）技术治疗，另一侧面部采用无 MLA 的常规技术（CT）治疗。FPT 技术使用 9mm 光斑，能量密度为 0.47J/cm，进行两次覆盖 40%面积的扫描。相比之下，CT 使用 4.5mm 手具，能量密度范围为 0.3 至 0.7J/cm。患者接受单次治疗，并在治疗后 2 周、1 个月、3 个月和 6 个月时评估色素清除率、PIH 发生情况和其他不良反应。
27 名参与者完成了研究方案。通过 3D 摄影分析色素清除率，FPT 技术（p<0.001）和 CT（p=0.004）治疗后 2 周至 6 个月均有显著改善。CT 侧 2 周、1 个月、3 个月和 6 个月时 PIH 发生率分别为 64%、80%、96%和 88%，而 FPT 技术侧分别为 8%、32%、36%和 16%。在整个随访期间，FPT 技术侧 PIH 的发生率明显低于 CT 侧。此外，FPT 技术侧有 1 名参与者（4%）出现短暂性和轻度色素减退，CT 侧有 5 名参与者（20%）出现色素减退。研究过程中未观察到其他不良反应。
532nm 皮秒激光是治疗 FST III-V 个体 SL 的一种安全有效的治疗方法。特别值得注意的是 FPT 技术的疗效，它在与 CT 相比具有相当疗效的同时，显著降低了 PIH 的发生率。
