皮肤病学的激光

给我们的读者注意。此页面逾期更新；发生了重大变化laser技术以来最初是编写的。

介绍

首先激光used to treat skin conditions occurred over 40 years ago.Argon和carbon dioxide (CO₂）激光were commonly used to treat良性血管胎记such as port-wine stains and出血。尽管这些胎记可以有效地减轻，但副作用是高度不可接受的瘢痕formation. In the last 20 years, advances in laser technology have revolutionised their use in the treatment of many skin conditions and先天性缺陷，包括血管和颜料ed病变，以及去除纹身，疤痕和皱纹。有一系列激光和轻型技术可用于皮肤重新铺面和恢复活力。

激光的特性

‘Laser’ is an acronym:lighta通过stimulatede任务r阿迪化。

激光是具有以下特性的高强度光源：

• 单色 - 辐射为单个波长
• 连贯的 - 光束波在相位
• 准直 - 光束并联传播

Laser light can be accurately focused into small spots with very high energy.

The light is produced within an optical cavity containing a medium, which may be a gas (eg,氩气，K k，二氧化碳），液体（例如，染料）或solid（例如，红宝石,neodymium:yttrium-aluminium-garnet,Alexandrite). The process involves excitation of themolecules激光培养基的光子在恢复稳定状态时会释放光子。每种培养基都会产生特定的光的光，可能在可见光谱（紫罗兰色400至红色700nm）或红外光谱（超过700 nm）之内。

Vascular skin lesions contain oxygenated血红蛋白，在418、542和577 nm处强烈吸收可见光，而色素皮肤病变含有melanin, which has a broad range of absorption in the visible and infrared wavebands. Infrared lasers are broadly destructive because they are absorbed by water in and between skin cells (these are composed of 70-90% water).

The aim is to destroy the target cells and not to harm the surrounding tissue. Short pulses reduce the amount that the damaged cells heat, thereby reducing thermal injury that could result in scarring. Automated scanners aim to reduce the chance of overlapping treatment areas.

有哪种类型的激光器？

There are several types of lasers used in skin laser surgery. Older laser technologies such as the continuous wave (CW) lasers of CO₂和氩气已被准CW模式激光器和脉冲激光系统替换。皮秒激光器脉冲非常短。

The wavelength peaks of the laser light, pulse durations and how the target skin tissue absorbs this, determine the clinical applications of the laser types.

激光可以治疗哪些皮肤状况？

Vascular lesions

Lasers have been used successfully to treat a variety of vascular lesions including superficial血管畸形(port-wine stains), facial丝血管酶,出血,化脓性granulomas,卡波西肉瘤和poikilodermaof Civatte。用于治疗这些疾病的激光器包括氩气，aptd，KTP，K K，铜蒸气，copper bromide, pulsed dye lasers andNd:YAG。Argon（CW）引起高度的非特异性热损伤和疤痕，现在在很大程度上被黄色的准cW和脉冲激光疗法所取代。

The脉冲染料激光由于它的激光被认为是大多数血管病变的激光器优越的临床efficacy和低风险的轮廓。它具有较大的斑点（5至10mm），可以快速治疗大病变。副作用包括术后瘀伤（purpura) that may last 1-2 weeks andtransient色素changes.结皮，很少看到纹理变化和疤痕。

新的V梁特征提供了超长的脉冲持续时间，因此针对目标的能量血管在更长的时间内，导致更均匀blood vesseldamage reducing the purpura seen with the earlier pulse dye lasers. The addition of dynamic cooling increases comfort during treatment enabling higher fluencies (energy) to be delivered safely and effectively, so fewer treatments are required.

与更深层血管相比，与较小的浅表血管相关的血管畸形对治疗的反应更好（在老年人中经常出现）。因此，最好尽早开始治疗。平均8至10处理后发生淡出80％。如果病变复发。

Treatment with quasi-CW lasers also produce effective outcomes, but they may be associated with higher incidences of scarring and textural changes. The most common side effects include milderythema,浮肿和瞬态结皮。

非激光器强烈的脉冲轻设备can also be used for treating vascular lesions.

脉冲染料激光处理

治疗后的瘀伤

色素病变和纹身

Melanin-specific, high energy, QS laser systems can successfully lighten or eradicate a variety of pigmented lesions. Pigmented lesions that are treatable include雀斑和胎记包括一些先天性melanocyticNaevi,蓝色Naevi,OTA/ITO的Naevi和Becker naevi。The short pulse laser systems effectively treat the lesions by confining their energy to themelanosomes，这是微小的颗粒在内部含有黑色素颜料细胞。激光治疗的结果取决于黑色素的深度和病变的颜色，并且在某种程度上是不可预测的。表面上的色素最好用较短的波长激光器处理，而去除较深的色素需要更长的波长激光器，这些激光器渗透到更大的组织深度上。需要谨慎laser therapy in skin of colour, as permanenthypopigmentation和depigmentation可能发生。成功治疗的病变可能recur。

在对色素病变进行激光治疗之前，任何病变atypicalfeatures should be biopsied to rule outmalignancy。先天性黑素细胞NAEVI的治疗是一个有争议的问题。使用激光促进的长期影响黑色素瘤尚不清楚，但这种治疗被认为是低风险。

QS激光系统可以选择性地破坏纹身色素，而不会对周围皮肤造成太大损害。通过清除白细胞，组织，将改性的色素从皮肤上取出巨噬细胞。激光的选择取决于纹身墨水的颜色，深度和化学性质。通常需要两到十个治疗。黄色，橙色和绿色是最困难的颜色去除。

• 黑色：QS红宝石,Alexandrite或者Nd:YAG
• 蓝色和绿色：QS红宝石,Alexandrite
• 黄色，橙色，红色：QSNd:YAG或PDL

与其他激光治疗一样，可能会发生色素和质地变化（包括疤痕）。

PicosecondNd:YAG and alexandrite lasers have been found to remove外源颜料比QS激光器更有效。

Hair移动

激光器可用于去除由于hypertrichosis或者妇女。激光疗法迅速去除黑发，可能需要3到6个月才能明显再生长。需要几个治疗周期，而处理之间的间距取决于正在处理的身体区域。激光治疗比电解。并发症很少见，但浅表灼伤，色素变化甚至可能发生疤痕。据报道，在接近治疗的区域的未处理区域中，细头发的生长增加了。增加和减少localised治疗后已经报告了出汗。

Suitable devices include long-pulsed红宝石和Alexandrite激光器，二极管（810nm），毫秒Nd:YAG和非激烈的强烈脉冲光。

脱毛

Temporary dark marks

Permanent white marks

面部的wrinkles, scars, and sun-damaged skin

面部的激光重铺使用高能量，脉冲和扫描激光器。

脉冲CO₂和ERBIUM：YAG激光器have been successful in reducing and removingfacial wrinkles，痤疮疤痕和阳光损坏的皮肤。高能，脉冲和扫描CO₂laser通常被认为是所有其他的黄金标准facial rejuvenation比较系统。通常在接受的患者中发现50％的改善CO₂激光治疗。治疗的副作用包括术后压痛，发红，肿胀和疤痕。发红和压痛持续了几周，而新皮肤在通过激光治疗去除受损皮肤的区域（ablativelaser systems). Secondary skin感染在愈合发生之前，包括疱疹的重新激活也是一个潜在的问题。将肤色较深的个体视为永久损失或变量时，需要极大的谨慎色素沉着可能会长期发生。

Erbium：yag与CO₂laser. Despite their side effect profile and long recovery time these ablative laser systems, when used properly, can produce excellent results.

Recently non-ablative lasers have been used fordermal造型;“非自动性”是指加热皮肤胶原while avoiding damage to the surface skin cells (表皮）冷却。需要多种治疗以使皮肤光滑。

Keloids和hypertrophic瘢痕s

酮和肥厚的疤痕很难根除,和传统treatm吗ents are not always successful. Vaporising lasers (CO₂和Erbium：Yag）作为常规手术的替代方法。最近，PDL已用于改善肥厚性疤痕和酮类疤痕。这可能需要多次治疗课程或同时使用感染性注射以获得良好的结果。据报道，PDL可以减少发红以及改善疤痕的质地和柔韧性。

激光的其他用途皮肤科

激光有时用于删除viral wartsby vaporisation (CO₂laser）或破坏真皮血管（PDL），但证据表明，这比标准的疣涂料更有效，甚至等待自发清除。

TheCO₂lasercan be used to remove a variety of skin lesions including塞波尔霍尼克角膜生成和皮肤癌通过蒸发或切割模式。但是，传统surgery或者electrosurgery也可以使用，通常便宜。

紫罗兰色金属卤化物光（407-420 nm）已用于治疗粉刺because it has a有毒的effect on the acne细菌,Cutibacterium acnes。

TheExcimer laser使用高贵的气体和卤素生产紫外线辐射(308 nm) that will clearpsoriasis斑块。但是，小的斑点大小和引起起泡的趋势使治疗时间很耗时且难以执行。

激光安全

安全预防措施将取决于使用了哪种激光系统以及在哪种设置中。他们应该包括：

• Thorough training of personnel
• Eye protection for the patient and clinic staff
• 警告通知程序室外
• Use of non-reflective instruments
• Avoidance of flammable materials.

激光的副作用

Laser treatments are burns. The following adverse effects may occur:

• Temporary pain, redness, bruising, blistering and crusting
• 感染，包括重新激活疱疹单纯形
• Pigment changes (brown and white marks), which may be permanent
• 疤痕。