Joussen A M, Kruse F E, Rohrschneider K, Völcker H E
Universitäts-Augenklinik Heidelberg.
Ophthalmologe. 1995 Aug;92(4):581-90.
Hitherto secondary cataract has been usually treated by Nd:YAG laser, which results in a dissection of the capsule with possible complications e.g. retinal detachment. Selective removal of the epithelial cells from the posterior capsule has not been possible. By use of dyes in connection with laser light of a suitable wavelength, lens epithelial cells could potentially be selectively destroyed. We investigated the dye indocyanine green, which has a peak absorbtion at the emission wavelength of commercially available diode lasers.
Human lens epithelial cells and 3T3 cells (mouse embryonal fibroblasts) were grown in MEM with 10% FBS. Confluent and preconfluent layers were incubated with indocyanine green and treated with a diode laser attached to a slit lamp (810 nm, Zeiss VISULAS, Zeiss Oberkochen, Germany).
Indocyanine green alone was toxic in concentrations above 5 mg/ml (60 min). Combined with laser treatment (200 mW, 100 ms, 160 microns), indocyanine green led to cell damage in preconfluent cultures at concentrations above 0.01 mg/ml (10 min). After about 2 days irradiated cells became necrotic and began to desquamate from the culture disc. Cells in confluent cultures could be devitalised at concentrations above 0.05 mg/ml (10 min) using the same power. In contrast, neither indocyanine green alone nor diode laser alone could interfere with epithelial proliferation.
The experiments show the possibility of dye-enhanced therapy of lens epithelial cells with indocyanine green and diode laser. In contrast to other photosensitizers, indocyanine green is widely used in human function tests. Therefore its use for the treatment of secondary cataracts may merit discussion.
迄今为止，后发性白内障通常采用钕钇铝石榴石激光治疗，这会导致晶状体囊膜切开，可能引发如视网膜脱离等并发症。从后囊膜选择性去除上皮细胞尚无可能。通过将染料与合适波长的激光联合使用，有可能选择性地破坏晶状体上皮细胞。我们研究了吲哚菁绿，它在市售二极管激光器的发射波长处有吸收峰值。
人晶状体上皮细胞和3T3细胞（小鼠胚胎成纤维细胞）在含10%胎牛血清的MEM培养基中培养。汇合和未汇合的细胞层用吲哚菁绿孵育，并用连接在裂隙灯上的二极管激光器（810nm，蔡司VISULAS，德国蔡司奥伯科亨）进行处理。
单独使用吲哚菁绿时，浓度高于5mg/ml（60分钟）具有毒性。与激光治疗（200mW，100ms，160微米）联合使用时，吲哚菁绿在浓度高于0.01mg/ml（10分钟）时会导致未汇合培养物中的细胞损伤。照射后约2天，细胞坏死并开始从培养皿上脱落。使用相同功率时，汇合培养物中的细胞在浓度高于0.05mg/ml（10分钟）时可被灭活。相比之下，单独的吲哚菁绿或二极管激光都不会干扰上皮细胞增殖。
实验表明了用吲哚菁绿和二极管激光进行染料增强治疗晶状体上皮细胞的可能性。与其他光敏剂不同，吲哚菁绿广泛用于人体功能测试。因此，其用于治疗后发性白内障可能值得探讨。
