McMeekin T O
University of Rochester, Rochester, NY, USA.
J Cutan Laser Ther. 1999 Sep;1(3):179-80. doi: 10.1080/14628839950516841.
Prior studies have shown improvement in leg telangiectasias using a long pulse, frequency-doubled nd:YAG laser at 532 nm. The following study, with longer follow-up, was undertaken to determine the effectiveness of this laser and incidence of side-effects from a single treatment for lower extremity telangiectasia of less than 1 mm in diameter.
Ten patients of skin types I-III received a single treatment on each of 18 treatment sites. One to three passes were used on each vessel with a repetition rate of 2 Hz. Two energy fluences of 12 J/cm2 and 16 J/cm2 were compared. Patients were followed for 1 year with follow-up photographs taken, from which the percentage of vessel clearance and side-effects were rated.
Overall, 44% of patients had a greater than 50% clearance from a single treatment using the frequency-doubled Nd:YAG laser at 532 nm. The higher fluence of 16 J/cm2 showed a better response than the lower fluence of 12 J/cm2. Side-effects were more marked and were seen in more patients treated at 16 J/cm2 than at the 12 J/cm2 setting. Some 94% of patients had hyperpigmentation that took up to 6 months to resolve. One patient treated at 16 J/cm2 experienced blisters, crusts and scarring, which persisted for 1 year. There was further improvement from 6 months to 1 year in one-third of the treatment sites.
The long-pulsed Nd:YAG laser at 532 nm with a chilled sapphire tip can treat leg telangiectasias of 0.5 to 1.0 mm in diameter with greater than 50% clearance at 44% of sites with a single treatment. Higher fluences of 16 J/cm2 demonstrated a greater clearance, but also greater adverse effects, including atrophic scarring persisting for 1 year. Further clinical improvement was seen at 6-month to 1-year follow-ups.
先前的研究表明，使用波长为532nm的长脉冲倍频钕：钇铝石榴石激光可改善腿部毛细血管扩张。本研究进行了更长时间的随访，以确定这种激光对直径小于1mm的下肢毛细血管扩张单次治疗的有效性及副作用发生率。
10例皮肤类型为I - III型的患者，其18个治疗部位均接受单次治疗。每条血管进行1至3次照射，重复频率为2Hz。比较了12J/cm²和16J/cm²两种能量密度。对患者进行1年的随访，并拍摄随访照片，据此评估血管清除率和副作用情况。
总体而言，44%的患者在使用波长为532nm的倍频钕：钇铝石榴石激光单次治疗后，血管清除率超过50%。16J/cm²的较高能量密度比12J/cm²的较低能量密度显示出更好的效果。副作用更明显，接受16J/cm²治疗的患者比接受12J/cm²治疗的患者更多见。约94%的患者出现色素沉着，需长达6个月才能消退。1例接受16J/cm²治疗的患者出现水疱、结痂和瘢痕，持续了1年。三分之一的治疗部位在6个月至1年期间有进一步改善。
配备冷却蓝宝石探头的波长为532nm的长脉冲钕：钇铝石榴石激光可治疗直径为0.5至1.0mm的腿部毛细血管扩张，单次治疗后44%的部位血管清除率超过50%。16J/cm²的较高能量密度显示出更高的清除率，但也有更严重的不良反应，包括持续1年的萎缩性瘢痕。在6个月至1年的随访中可见进一步的临床改善。
