Walkow T, Anders N, Pham D T, Wollensak J
Department of Ophthalmology, Medical Faculty of Humboldt University of Berlin, Germany.
Graefes Arch Clin Exp Ophthalmol. 1998 Jan;236(1):9-12. doi: 10.1007/s004170050035.
Severe decentration and subluxation of intraocular lenses (IOLs) may lead to double vision, glare and deterioration of vision to the point of functional aphakia. The purpose of the present study was to analyse causes for severe IOL dislocation.
Between January 1989 and January 1996, 37 patients required IOL exchange because of decentrated or subluxated posterior chamber lenses. Twenty-five of the exchanged lenses were implanted in our hospital, 12 lenses elsewhere. After explantation the lenses were examined by light and electron microscopy.
In 10 eyes, asymmetric implantation of the posterior chamber lens was responsible for decentration. Three of the lenser concerned were multifocal IOLs. Asymmetric implantation led to a significantly higher rate of explantations in eyes with multifocal lenses (P < 0.005). In five eyes decentration developed due to asymmetric capsular shrinkage, in four eyes due to posterior synechiae. A lens subluxation developed in three eyes as a result of rupture of the posterior capsule and in nine eyes because of zonular defects. In three cases decentrations were induced by an extensive secondary cataract. Macroscopically visible changed geometry of the haptics was found in nine lenses; eight of these had polypropylene haptics. Seven lenses showed severely altered haptics on electron-microscopic examination. In four eyes subluxated lenses had to be explanted together with the capsular bag because of severe defects of the zonula, which caused decentration in nine eyes.
Asymmetric implantation of posterior chamber lenses should be strictly avoided. Multifocal lenses require special attention concerning symmetric capsulorhexis and positioning of their haptics.
人工晶状体（IOL）严重偏位和半脱位可能导致复视、眩光以及视力下降至功能性无晶状体状态。本研究的目的是分析严重IOL脱位的原因。
1989年1月至1996年1月期间，37例患者因后房型晶状体偏位或半脱位需要更换IOL。其中25枚更换的晶状体在我院植入，12枚在其他地方植入。取出晶状体后，通过光镜和电镜进行检查。
10只眼中，后房型晶状体不对称植入导致偏位。其中3枚相关晶状体为多焦点IOL。不对称植入导致多焦点晶状体眼的取出率显著更高（P<0.005）。5只眼中偏位是由于囊膜不对称收缩所致，4只眼是由于后粘连。3只眼因后囊破裂发生晶状体半脱位，9只眼因悬韧带缺损发生半脱位。3例偏位是由广泛的继发性白内障引起。在9枚晶状体中发现触觉部分宏观可见的几何形状改变；其中8枚有聚丙烯触觉部分。7枚晶状体在电镜检查中显示触觉部分严重改变。4只眼中半脱位的晶状体因悬韧带严重缺损必须与囊袋一起取出，悬韧带缺损在9只眼中导致偏位。
应严格避免后房型晶状体的不对称植入。多焦点晶状体在连续环形撕囊和触觉部分定位方面需要特别注意。
