Hainsworth D P, Chen S N, Cox T A, Jaffe G J
Department of Ophthalmology, Duke University, Durham, NC, USA.
Ophthalmology. 1996 Sep;103(9):1410-8. doi: 10.1016/s0161-6420(96)30490-9.
Condensation occurs rapidly on silicone intraocular lenses (IOLs) after vitrectomy and fluid-air exchange in the presence of a posterior capsulotomy, severely limiting the retinal view. Foldable IOLs made of an acrylic polymer are now available. The authors compare the condensation and subsequent retinal view degradation after vitrectomy and fluid-air exchange in rabbit eyes implanted with polymethylmethacrylate (PMMA), soft acrylic polymer (ACRYSOF), and silicone IOLs.
Thirty rabbits underwent bilateral lens removal. Twenty PMMA, 20 acrylic polymer, and 20 silicone IOLs were implanted into the capsular bag. After three-port vitrectomy, eyes were randomly assigned to undergo a posterior capsulotomy or to an intact posterior capsule. Fluid-air exchange was performed, and the amount of condensation on the IOL surface and resultant retinal view was graded. Surgical maneuvers then were performed to decrease the condensation. These maneuvers included wiping the IOL surface with a soft-tipped cannula and coating it with viscoelastic.
No condensation occurred on IOLs in eyes with an intact posterior capsule. Significantly more condensation occurred on IOLs in eyes with a capsulotomy, regardless of IOL type (P < 0.014). Wiping the condensation resulted in significantly less condensation and improved retinal view on the PMMA and acrylic IOLs when compared with the silicone IOLs (P < 0.024). Condensation was eliminated on all three IOL types after viscoelastic was applied. However, increased distortion of the retinal view was induced by the viscoelastic on the silicone IOL as compared with the other IOLs.
Condensation and subsequent retinal image degradation occurs uniformly after vitrectomy, posterior capsulotomy, and fluid-air exchange in eyes with PMMA, acrylic, and silicone IOLs. Because the condensation can be eliminated most easily on acrylic IOLs compared with silicone IOLs, when foldable IOL techniques are used it is likely that an acrylic polymer IOL would be advantageous for those patients at risk for future vitreous procedures requiring fluid-air exchange.
在玻璃体切割术及液气交换后，存在后囊切开的情况下，硅胶人工晶状体（IOL）上会迅速出现冷凝现象，严重限制视网膜视野。现在有由丙烯酸聚合物制成的可折叠IOL。作者比较了植入聚甲基丙烯酸甲酯（PMMA）、软性丙烯酸聚合物（ACRYSOF）和硅胶IOL的兔眼在玻璃体切割术及液气交换后的冷凝情况及随后视网膜视野的退化情况。
30只兔子接受双侧晶状体摘除术。将20个PMMA、20个丙烯酸聚合物和20个硅胶IOL植入囊袋内。在三通道玻璃体切割术后，将眼睛随机分为接受后囊切开术或后囊完整的两组。进行液气交换，并对IOL表面的冷凝量及由此产生的视网膜视野进行分级。然后进行手术操作以减少冷凝。这些操作包括用软头套管擦拭IOL表面并用粘弹性物质覆盖。
后囊完整的眼中IOL上未出现冷凝现象。无论IOL类型如何，后囊切开的眼中IOL上出现的冷凝明显更多（P < 0.014）。与硅胶IOL相比，擦拭冷凝物后，PMMA和丙烯酸IOL上的冷凝明显减少，视网膜视野得到改善（P < 0.024）。应用粘弹性物质后，所有三种IOL类型上的冷凝均被消除。然而，与其他IOL相比，硅胶IOL上的粘弹性物质导致视网膜视野的变形增加。
在植入PMMA、丙烯酸和硅胶IOL的眼中，玻璃体切割术、后囊切开术及液气交换后均会出现冷凝及随后的视网膜图像退化。由于与硅胶IOL相比，丙烯酸IOL上的冷凝最容易消除，因此当使用可折叠IOL技术时，对于那些未来有需要液气交换的玻璃体手术风险的患者，丙烯酸聚合物IOL可能具有优势。
