Saager Rolf B, Hassan Khaled M, Kondru Clement, Durkin Anthony J, Kelly Kristen M
Beckman Laser Institute and Medical Clinic, University of California-Irvine, Irvine, California 92617, USA.
Lasers Surg Med. 2013 Jan;45(1):15-21. doi: 10.1002/lsm.22084. Epub 2013 Jan 15.
Generalized argyria is a blue-gray hyperpigmentation of the skin resulting from ingestion or application of silver compounds, such as silver colloid. Case reports have noted improvement after Q-Switched Neodymium-Yttrium Aluminum Garnet laser (1,064 nm QS Nd:YAG) laser treatment to small surface areas. No reports have objectively monitored laser treatment of generalized argyria over large areas of skin, nor have long-term outcomes been evaluated.
STUDY DESIGN/MATERIALS AND METHODS: An incremental treatment plan was developed for a subject suffering from argyria. A quantitative near infrared spectroscopic measurement technique was employed to non-invasively analyze tissue-pigment characteristics pre- and post-laser treatment. Post-treatment measurements were collected at weeks 1, 2, 3, and 4, and again at 1 year.
Immediate apparent removal of pigment was observed with 1 Q-switched 1,064 nm Nd:YAG laser treatment (3-6 mm spot; 0.8-2 J/cm(2) ) per area. Entire face, neck, upper chest, and arms were treated over multiple sessions. Treatments were very painful and general anesthesia was utilized in order to treat large areas. Near-infrared spectroscopy was used to characterize and quantify the concentration of silver particles in the dermis based on the absorption features of the silver particles as well as the optical scattering effects they impart. We were able to estimate that there was, on average, 0.042 mg/ml concentration of silver prior to treatment and that these levels went below the minimum detectable limit of the instrument post-treatment. There was no recurrence of discoloration over the 1-year study period.
QS 1,064 nm laser treatment of argyria is a viable method to restore normal skin pigmentation with no evidence of recurrence over study period. Quantitative spectroscopic measurements: (1) confirmed dyspigmentation was due to silver, (2) validated our clinical assessment of no recurrence up to 1-year post-treatment, and (3) indicated no collateral tissue damage with treatments.
泛发性银质沉着症是因摄入或应用银化合物（如银胶体）导致皮肤出现蓝灰色色素沉着。病例报告指出，调Q钕钇铝石榴石激光（1064 nm调Q Nd:YAG）治疗小面积皮肤后症状有所改善。尚无关于大面积泛发性银质沉着症激光治疗的客观监测报告，也未对长期疗效进行评估。
研究设计/材料与方法：为一名银质沉着症患者制定了递增治疗方案。采用定量近红外光谱测量技术对激光治疗前后的组织色素特征进行无创分析。在第1、2、3和4周以及1年后进行治疗后测量。
每区域单次调Q 1064 nm Nd:YAG激光治疗（光斑3 - 6 mm；能量密度0.8 - 2 J/cm²）后，色素立即明显消退。多疗程治疗了整个面部、颈部、上胸部和手臂。治疗过程非常疼痛，为治疗大面积皮肤采用了全身麻醉。基于银颗粒的吸收特征及其产生的光散射效应，利用近红外光谱对真皮中银颗粒的浓度进行表征和定量。我们能够估计出治疗前银的平均浓度为0.042 mg/ml，治疗后这些水平降至仪器的最低检测限以下。在1年的研究期内，色素沉着未复发。
调Q 1064 nm激光治疗银质沉着症是恢复正常皮肤色素沉着的可行方法，在研究期内无复发迹象。定量光谱测量：（1）证实色素沉着异常是由银所致，（2）验证了我们对治疗后1年无复发的临床评估，（3）表明治疗未造成附带组织损伤。
