Schallen Konika Patel, Seder Madelyn, Jorgenson Michael, Schomacker Kevin, Bhawan Jag
Candela, Marlborough, Massachusetts, USA.
Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts, USA.
Lasers Surg Med. 2025 Jan;57(1):54-62. doi: 10.1002/lsm.23842. Epub 2024 Sep 15.
Non-ablative fractional lasers (NAFL) have increased in demand compared to ablative laser treatments as they provide lesser down time, fewer side-effects, and are safer to use. Non-ablative fractional treatment with lasers ranging from 1320 to 1927-nm have been shown to be safe and effective for skin resurfacing procedures. The objective of this study is to investigate healing of the 1940-nm NAFL-induced microthermal treatment zones (MTZs) in human skin from a histologic perspective.
Three subjects received 1940-nm NAFL treatment to test areas on the abdomen at various timepoints during the study. The minimum 5 mJ/MTZ and maximum 20 mJ/MTZ energy settings were used at 20% coverage. Biopsies were taken coinciding with immediately posttreatment, 1, 3, 7 days, and 6 weeks posttreatment. Blinded analysis of hematoxylin and eosin stained slides was performed to measure the width and depth of the MTZs and evaluate the inflammatory and healing response of the skin over time (immediately to 6 weeks posttreatment). Safety was evaluated by assessing local skin responses and adverse events immediately after treatment and at all study visits.
Histological analysis of tissue following NAFL 1940-nm treatments showed mild early inflammatory response (presence of lymphotic infiltrate) in some test areas and zones of necrosis and coagulation having widths and depths (immediately-3 days posttreatment) that scaled with the 1940-nm pulse energy. Signs of healing such as presence of dermal mucin, evidence of fibrosis, and absence of necrosis were observed long-term (7 days to 6 weeks posttreatment). Evidence of the MTZ persisted beyond the 6-week study and was predicted to last for 100 days. All local clinical skin responses healed within 6 weeks and were limited to mild, transient erythema and edema which resolved in less than 12-24 h following treatment. No serious adverse events occurred during the study.
NAFL 1940-nm treatments are safe for inducing small fractional coagulation and necrosis zones in abdominal skin. NAFL 1940-nm laser creates fractional columns of injury with sufficient depth and coverage that suggest effective skin resurfacing, like other non-ablative fractional lasers.
与剥脱性激光治疗相比，非剥脱性分次激光（NAFL）的需求有所增加，因为它们的停机时间更短、副作用更少且使用更安全。已证明波长在1320至1927纳米之间的非剥脱性分次激光治疗对于皮肤表面重建手术是安全有效的。本研究的目的是从组织学角度研究1940纳米非剥脱性分次激光诱导的微热治疗区（MTZ）在人体皮肤中的愈合情况。
三名受试者在研究期间的不同时间点接受了1940纳米非剥脱性分次激光对腹部测试区域的治疗。使用最低5 mJ/MTZ和最高20 mJ/MTZ的能量设置，覆盖率为20%。在治疗后即刻、1天、3天、7天和6周时进行活检。对苏木精和伊红染色的切片进行盲法分析，以测量MTZ的宽度和深度，并评估皮肤随时间（治疗后即刻至6周）的炎症和愈合反应。通过在治疗后即刻及所有研究访视时评估局部皮肤反应和不良事件来评估安全性。
对接受1940纳米非剥脱性分次激光治疗后的组织进行组织学分析显示，在一些测试区域有轻度早期炎症反应（存在淋巴细胞浸润），以及坏死和凝固区域，其宽度和深度（治疗后即刻至3天）与1940纳米脉冲能量成比例。长期（治疗后7天至6周）观察到愈合迹象，如真皮粘蛋白的存在、纤维化的证据以及无坏死。MTZ的证据在6周研究期后仍然存在，预计持续100天。所有局部临床皮肤反应在6周内愈合，仅限于轻度、短暂的红斑和水肿，在治疗后不到12 - 24小时内消退。研究期间未发生严重不良事件。
1940纳米非剥脱性分次激光治疗对于在腹部皮肤中诱导小的分次凝固和坏死区域是安全的。1940纳米非剥脱性分次激光产生具有足够深度和覆盖率的分次损伤柱，表明与其他非剥脱性分次激光一样，具有有效的皮肤表面重建效果。
