激光脱毛术后家狗皮肤组织学和超微结构变化

Histological and ultrastructural changes of dog skin following hair removal by laser

目的 :探讨翠绿宝石激光脱毛术后的皮肤组织学和超微结构的改变。方法 :对 7只黑毛狗用翠绿宝石激光脱毛 ,术后 0 .5 h,2、3、5、10及 30 d分别取材 ,在光镜和透射电镜下观察皮肤标本。结果 :激光术后 ,皮肤中毛干凝固及碳化 ,治疗区损伤的毛囊与未损伤的毛囊散乱分布 ,黑素细胞分布多的基底层可见微观改变。术后 10 d内可见轻微的炎性反应。能量大的治疗区毛囊损伤程度大 ,单脉冲及双脉冲激光术后毛囊损伤程度无明显差异。结论 :翠绿宝石激光对毛囊有选择性损伤作用 ,同时有表皮基底层的微观改变 ,术后无疤痕形成 ;翠绿宝石激光脱毛的疗效有能量依赖性 ;双脉冲与单脉冲激光脱毛疗效无明显差异 ;激光枪头备有冷却装置可减少术后的副反应。

Objective: To evaluate the cutaneous histological and ultrastructural changes of dogs following hair removal by Alexandrite laser. Methods: Seven healthy dogs with dark hair were treated for hair removal with the Alexandrite laser and skin biopsies were taken after 0.5 h,2,3,5,10,and 30 days. Specimens were examined with light microscopy and transmission electron microscopy. Results: Laser-treated specimens showed widespread coa-gulation and charring subcutaneous hair shafts. These obviously damaged follicles were randomly dispersed among intact follicles within the same treatment sites. Microscopic changes were also seen in the basal epidermis where melanin was concentrated. A low level of inflammatory response was seen up to 10 days followed laser treatment. The efficiency in higher fluence test area was better than the lower one; the degree of damaged follicles with double pulse was similar to that with single pulse. Conclusion: Alexandrite laser irradiation results in selective damage to follicles and microscopic changes in the basal epidermis. Alexandrite laser hair removal does not lead to scar formation; the efficiency of laser hair removal is fluence-depent; the degree of damaged follicles with double pulse is not different with single one; the cooled hand piece can minimize epidermal injury.