Lira Madalena, Dos Santos Castanheira Elisabete M, Santos Lívia, Azeredo Joana, Yebra-Pimentel Eva, Real Oliveira M Elisabete C D
Centre of Physics, School of Sciences, University of Minho, Minho, Portugal.
Optom Vis Sci. 2009 Apr;86(4):332-9. doi: 10.1097/OPX.0b013e318198d047.
To evaluate the influence of wear of silicone-hydrogel contact lenses on lens ultraviolet and visible spectrum transmittance by studying several contact lenses before and after wear.
To investigate the ability of contact lenses to maintain their transmittance characteristics, we measured 104 different contact lenses in the ultraviolet (UV) and visible range from 200 to 700 nm, with a Shimadzu UV3101-PC UV-vis-NIR spectrophotometer equipped with an integrating sphere. The lenses used in this study were Acuvue Advance (Johnson & Johnson Vision Care, Inc.), Air Optix Night & Day (CIBA Vision), Air Optix (CIBA Vision), and PureVision (Bausch & Lomb). A conventional hydrogel contact lens was also tested, Acuvue (Johnson & Johnson Vision Care Inc.).
Our study indicates that lenses that do not have UV absorbers incorporated into the polymer transmitted most of the UV radiation (UVR) before and after wear. The results of the statistical analysis show that for the UVC portion of the spectrum significant difference exists within the measurements obtained before and after wear for all the lenses, with the exception of PureVision. Acuvue Advance is the only material in which significant transmittance differences were observed in the visible spectral range.
Transmittance is modified after contact lenses wear, probably due to the formation of biofilms on the contact lens surface, being more noticeable in the UVR region of the spectrum (200-400 nm). Silicone-hydrogel and conventional hydrogel contact lens materials that provide UVR protection (UV-blocker) maintain this property even after being worn. The changes observed in the visible spectrum seem not to have any implications in visual performance of silicone-hydrogel contact lenses.
通过研究几种隐形眼镜佩戴前后的情况，评估硅水凝胶隐形眼镜的磨损对镜片紫外线及可见光谱透过率的影响。
为研究隐形眼镜保持其透过率特性的能力，我们使用配备积分球的岛津UV3101 - PC紫外可见近红外分光光度计，在200至700纳米的紫外（UV）和可见光范围内测量了104种不同的隐形眼镜。本研究中使用的镜片有Acuvue Advance（强生视力健公司）、Air Optix Night & Day（视康）、Air Optix（视康）和PureVision（博士伦）。还测试了一种传统水凝胶隐形眼镜Acuvue（强生视力健公司）。
我们的研究表明，聚合物中未加入紫外线吸收剂的镜片在佩戴前后能透过大部分紫外线辐射（UVR）。统计分析结果显示，对于光谱的UVC部分，除了PureVision外，所有镜片在佩戴前后的测量值之间存在显著差异。Acuvue Advance是唯一在可见光谱范围内观察到显著透过率差异的材料。
隐形眼镜佩戴后透过率会发生改变，这可能是由于隐形眼镜表面形成生物膜所致，在光谱的UVR区域（200 - 400纳米）更为明显。提供UVR防护（紫外线阻滞剂）的硅水凝胶和传统水凝胶隐形眼镜材料即使在佩戴后仍能保持这一特性。在可见光谱中观察到的变化似乎对硅水凝胶隐形眼镜的视觉性能没有任何影响。
