Jacobi F K, Kessler W, Held S
Ambulantes Zentrum für Augenoperationen, Siemensstrasse 13, 35394 Giessen.
Ophthalmologe. 2007 Mar;104(3):236-42. doi: 10.1007/s00347-006-1452-2.
Reduced contrast sensitivity, glare disability and insufficient bifocality are the main drawbacks of multifocal intraocular lenses (IOL). The bilateral implantation of diffractive IOL with an asymmetrical light distribution for distance and near focus is an alternative concept that aims to improve the contrast sensitivity and bifocality of conventional multifocal IOL.
The optical performance of monofocal (PhacoFlexII SI40) and multifocal IOL (Array SA40N; Acri. Twin 737D/733D) was quantitatively assessed in 18 healthy probands and qualitatively determined by digital photographic recording using an optical apparatus, the "physical eye", according to Reiner and Jacobi. Vision examination included standard tests of distance and near visual acuity, contrast sensitivity and low contrast visual acuity testing under varying pupil size using a video acuity tester.
Distance visual acuity was significantly superior with the SI40 and distant-dominant 737D compared to the SA40N and near-dominant 733D. At near, the 733D had the best performance. Contrast sensitivity was better with the 737D than the SA40N when both were compared with the SI40. No normal contrast sensitivity could be determined with the 733D because of the optical phenomenon of 'spurious resolution'. Variation in pupil size had less impact on contrast acuity with the Acri. Twin IOL compared to the SI40 and SA40N. Photographic testing revealed better edge contrast with the Acri. Twin than the SA40N.
The optical performance of multifocal IOL correlates with the properties of physical light distribution. Differences in edge contrast may be discerned using photographic recording.
对比敏感度降低、眩光障碍和双焦点不足是多焦点人工晶状体(IOL)的主要缺点。植入具有不对称远近焦点光分布的衍射型IOL是一种旨在改善传统多焦点IOL对比敏感度和双焦点功能的替代方案。
对18名健康受试者的单焦点IOL(PhacoFlexII SI40)和多焦点IOL(Array SA40N;Acri.Twin 737D/733D)的光学性能进行了定量评估,并根据赖纳和雅可比的方法,使用“物理眼”光学仪器通过数字摄影记录进行了定性测定。视力检查包括使用视频视力测试仪在不同瞳孔大小下进行的远、近视力、对比敏感度和低对比度视力标准测试。
与SA40N和近焦点占优的733D相比,SI40和远焦点占优的737D的远视力明显更好。在近视力方面,733D表现最佳。与SI40相比,737D的对比敏感度优于SA40N。由于“伪分辨”光学现象,无法确定733D的正常对比敏感度。与SI40和SA40N相比,Acri.Twin IOL的瞳孔大小变化对对比视力的影响较小。摄影测试显示,Acri.Twin的边缘对比度优于SA40N。
多焦点IOL的光学性能与物理光分布特性相关。使用摄影记录可以辨别边缘对比度的差异。