Beattie Tara K, Tomlinson Alan, McFadyen Angus K
Department of Vision Sciences, Glasgow Caledonian University, Glasgow, Scotland, United Kingdom.
Ophthalmology. 2006 Jan;113(1):117-25. doi: 10.1016/j.ophtha.2005.10.018. Epub 2005 Dec 19.
To investigate the attachment of Acanthamoeba to first- and second-generation silicone hydrogel contact lenses, and to determine if patient wear or the presence of a bacterial biofilm coating affects attachment characteristics.
Experimental study.
Attachment to the silicone hydrogel lenses was compared with that to a conventional hydrogel control lens. Sixteen replicates (n = 16) were carried out for unworn, worn, and biofilm-coated lenses of each type.
Unworn, worn, and Pseudomonas aeruginosa biofilm-coated first-generation (lotrafilcon A) and second-generation (galyfilcon A) silicone hydrogel and conventional hydrogel (etafilcon A) lens quarters were incubated for 90 minutes in suspensions of plate-cultured Acanthamoeba castellanii trophozoites.
Trophozoites attached to one surface of each lens quarter were counted by direct light microscopy. Logarithmic transformation of data allowed the use of parametric analysis of variance for statistical analysis.
Attachment of Acanthamoeba was affected significantly by lens material type (P<0.001), with higher numbers of trophozoites attaching to the first-generation lotrafilcon A silicone hydrogel lens, compared with the second-generation galyfilcon A lens and the conventional hydrogel lens. Attachments to the latter 2 lenses did not differ significantly from each other (P = 0.126). Patient wear and the presence of a bacterial biofilm had no significant effect on attachment to the lotrafilcon A lens (P = 0.426) but did significantly increase attachment to the galyfilcon A (P<0.001) and the etafilcon A (P = 0.009) lenses; attachment to the latter 2 lenses was still significantly less than that found with the first-generation silicone hydrogel (P<0.001).
Acanthamoeba demonstrated a significantly greater affinity for the first-generation silicone hydrogel lens as compared with the second-generation silicone hydrogel and the conventional hydrogel. If exposed to Acanthamoeba (e.g., when showering or swimming, through noncontinuous wear and ineffective lens care regimes), first-generation silicone hydrogel lenses may promote a greater risk of Acanthamoeba infection due to the enhanced attachment characteristics of this lens material. However, prospective studies in patients are required to determine if these experimental results are clinically significant.
研究棘阿米巴对第一代和第二代硅水凝胶隐形眼镜的附着情况，并确定患者佩戴或细菌生物膜涂层的存在是否会影响附着特性。
实验研究。
将硅水凝胶镜片的附着情况与传统水凝胶对照镜片的附着情况进行比较。对每种类型的未佩戴、已佩戴和有生物膜涂层的镜片进行16次重复实验（n = 16）。
将第一代（lotrafilcon A）和第二代（galyfilcon A）硅水凝胶以及传统水凝胶（etafilcon A）镜片的未佩戴、已佩戴和被铜绿假单胞菌生物膜覆盖的镜片块在平板培养的卡氏棘阿米巴滋养体悬浮液中孵育90分钟。
通过直接光学显微镜对附着在每个镜片块一个表面上的滋养体进行计数。对数据进行对数转换后，可使用参数方差分析进行统计分析。
棘阿米巴的附着受到镜片材料类型的显著影响（P<0.001），与第二代galyfilcon A镜片和传统水凝胶镜片相比，附着在第一代lotrafilcon A硅水凝胶镜片上的滋养体数量更多。后两种镜片之间的附着情况差异不显著（P = 0.126）。患者佩戴和细菌生物膜的存在对lotrafilcon A镜片的附着没有显著影响（P = 0.426），但确实显著增加了对galyfilcon A（P<0.001）和etafilcon A（P = 0.009）镜片的附着；后两种镜片的附着仍显著低于第一代硅水凝胶镜片（P<0.001）。
与第二代硅水凝胶和传统水凝胶相比，棘阿米巴对第一代硅水凝胶镜片表现出显著更高的亲和力。如果暴露于棘阿米巴（例如，淋浴或游泳时，通过不连续佩戴和无效的镜片护理方案），由于这种镜片材料增强的附着特性，第一代硅水凝胶镜片可能会增加棘阿米巴感染的风险。然而，需要对患者进行前瞻性研究以确定这些实验结果是否具有临床意义。
