Korynta J, Bok J, Cendelin J
1st Department of Ophthalmology, Charles University, Prague, Czech Republic.
J Refract Corneal Surg. 1994 Sep-Oct;10(5):556-64.
Intraocular lens (IOL) decentration and tilt may affect postoperative refractive errors through spherical aberration of the IOL.
Through a use of a ray-tracing program and by minimizing algorithm, we calculated theoretical refractive errors for various degrees of IOL decentration and tilt. We compared our results with those obtained by paraxial vergence calculations.
IOL decentration and/or tilt shifted postoperative refractive errors toward myopia and astigmatism of oblique origin. For example, a 3-millimeter decentration of an IOL resulted in induction of approximately -2.00 diopters (D) sphere and +0.70 D cylinder. IOL tilt affected refractive errors to a lesser degree. The change in refractive error caused by a combination of IOL decentration and tilt depended on the relationship between the geometrical axes of decentration and tilt. In the case of the least favorable combination of 12 degrees of tilt and 3 mm of decentration, it can reach -7.00 D sphere and +4.00 D cylinder.
IOL decentration and/or tilt increase myopia and astigmatism. They are negligible for small decentrations, but could be sources of substantial postoperative refractive errors if the decentration or tile is large.
人工晶状体（IOL）的偏心和倾斜可能通过IOL的球差影响术后屈光不正。
通过使用光线追踪程序并采用最小化算法，我们计算了不同程度IOL偏心和倾斜时的理论屈光不正。我们将结果与通过近轴聚散度计算得到的结果进行了比较。
IOL偏心和/或倾斜使术后屈光不正向近视和斜轴散光方向偏移。例如，IOL 3毫米的偏心导致约-2.00屈光度（D）的球镜度和+0.70 D的柱镜度。IOL倾斜对屈光不正的影响较小。IOL偏心和倾斜共同作用引起的屈光不正变化取决于偏心和倾斜的几何轴之间的关系。在倾斜12度和偏心3毫米的最不利组合情况下，可达到-7.00 D的球镜度和+4.00 D的柱镜度。
IOL偏心和/或倾斜会增加近视和散光。对于小的偏心，它们可以忽略不计，但如果偏心或倾斜较大，可能是术后屈光不正的重要来源。
