水凝胶折叠式人工晶状体远期混浊的观察

Observation of late postoperative opacification of hydrogel intraocular lens

目的 实验室及临床观察分析超声乳化白内障吸除联合水凝胶折叠式人工晶状体（IOL）植入术后远期发生混浊的原因.方法 对4例（4只眼）超声乳化白内障吸除联合水凝胶折叠式IOL植入术后12.0～96.0个月（平均33.2个月）发生IOL混浊的患者进行临床观察.其中2例（2只眼）患者行IOL置换术,取出的2枚IOL进行钙特异性茜素红染色病理学检查,用扫描电镜观察混浊IOL表面沉淀物的位置和形态,应用能谱分析法检测沉淀物中的元素成分.结果 裂隙灯显微镜下见白色细小颗粒沉积于IOL前表面.电镜扫描可见有层次感、上下交错,如珊瑚样的颗粒附着于IOL表面.茜素红染色见钙结节和非特异性染色的细胞,能谱分析证实颗粒中含钙和磷元素.结论 水凝胶折叠式IOL表面混浊为颗粒状钙和磷化合物沉淀结晶所致,可能与水凝胶IOL材料易于发生钙磷沉积有关,但确切的发生机制还待更进一步研究.

Objective To report clinical, histopathologic, ultrastructural, and chemical features of extracted hydrogel intraocular lens （ IOL, Bausch and Lomb, H60M） from patients who had visual disturbances caused by postoperative opacification of the lens, and discuss the possible causes of this phenomenon. Methods Four cases （4 eyes） were presented after uneventful phacoemulsification and IOL implantation. Two IOLs were removed from 2 patients （2 eyes） with severe decreased visual acuity. Clinical aspects of patients who had opacification of this IOL were observed. Extracted lenses were stained with alizarin red （special stains for calcium） , examined by scanning electron microscope （SEM） and energy dispersive x-ray spectroscopy （ EDS）. Results The extracted lenses showed positive staining for alizarin red, indicating that calcium was present on the surface. SEM disclosed coralliform deposits on the superficial substance of the IOL optic. EDS showed that the presence of calcium and phosphorus mainly in the opacification region. Conclusions The surface of the IOL is subject to opacification as a result of calcium phosphate deposition, thereby limiting the patient＇s visual outcome, and in some cases necessitating the extraction of the lens. These changes may be relavent to the nature of the materials used for the construction of hydrogel IOLs. This important clinical problem requires further studies.