Department of Ophthalmology, Kyiv City Clinical Ophthalmological Hospital, Eye Microsurgical Center, Kyiv, Ukraine.
Department of Ophthalmology, Specialty Eye Hospital Svjetlost, Zagreb, Croatia.
Indian J Ophthalmol. 2021 Dec;69(12):3503-3510. doi: 10.4103/ijo.IJO_572_21.
To determine the significance of any association between either change in angle kappa (Κ°) or the rectilinear displacement (L, mm) of the first Purkinje image relative to the pupil center and unexpected changes in astigmatism after phacoemulsification.
Orbscan II (Bausch and Lomb) measurements were taken at 1, 2, and 3 months after unremarkable phacoemulsification in patients implanted with spherical (group 1, SA60AT, Alcon) or aspheric (group 2, SN60WF, Alcon) nontoric IOLs. The outputs were used to calculate L. Astigmatism, measured by autorefractometry and subjective refraction, was subjected to vector analysis (polar and cartesian formats) to determine the actual change induced over the periods 1-2 and 2-3 months postop.
Chief findings were that the mean (n, ±SD, 95%CI) values for L over each period were as follows: Group 1, 0.407 (38, ±0.340, 0.299-0.521), 0.315 (23, ±0.184, 0.335-0.485); Group 2, 0.442 (45, ±0.423, 0.308-0.577), 0.372 (26, ±0.244, 0.335-0.485). Differences between groups were not significant. There was a significant linear relationship between (A) the change in Κ (ΔΚ = value at 1 month-value at 2 months) and Κ at 1 month (x), where ΔΚ =0.668-3.794X (r = 0.812, n = 38, P = <0.001) in group 1 and ΔΚ = 0.263x -1.462 (r = 0.494, n = 45, P = 0.002) in group 2, (B) L and the J vector describing the actual change in astigmatism between 1 and 2 months in group 2, where J (by autorefractometry) =0.287L-0.160 (r = 0.487, n = 38, P = 0.001) and J (by subjective refraction) =0.281L-0.102 (r = 0.490, n = 38, P = 0.002), and (C) J and ΔΚ between 2 and 3 months in group 2, where J (by subjective refraction) =0.086ΔΚ-0.063 (r = 0.378, n = 26, P = 0.020).
Changes in the location of the first Purkinje image relative to the pupil center after phacoemulsification contributes to changes in refractive astigmatism. However, the relationship between the induced change in astigmatism resulting from a change in L is not straightforward.
确定在超声乳化手术后，第一主焦线相对于瞳孔中心的角度变化（Κ°）或直线位移（L，mm）的任何变化与散光的意外变化之间是否存在关联。
在植入球面（第 1 组，SA60AT，Alcon）或非球面（第 2 组，SN60WF，Alcon）非散光 IOL 的患者中，在无明显超声乳化手术后 1、2 和 3 个月，使用 Orbscan II（Bausch and Lomb）进行测量。结果用于计算 L。通过自动折射仪和主观折射术测量的散光进行向量分析（极坐标和笛卡尔格式），以确定手术 1-2 个月和 2-3 个月期间实际的变化。
主要发现是，每个时间段 L 的平均值（n，±SD，95%CI）值如下：第 1 组，0.407（38，±0.340，0.299-0.521），0.315（23，±0.184，0.335-0.485）；第 2 组，0.442（45，±0.423，0.308-0.577），0.372（26，±0.244，0.335-0.485）。组间差异无统计学意义。（A）在第 1 个月和第 2 个月之间变化的 Κ（ΔΚ=第 1 个月的值-第 2 个月的值）与第 1 个月的 Κ（x）之间存在显著的线性关系，其中ΔΚ=0.668-3.794X（r=0.812，n=38，P<0.001）在第 1 组，和ΔΚ=0.263x-1.462（r=0.494，n=45，P=0.002）在第 2 组，（B）L 和描述第 2 组第 1 个月和第 2 个月之间实际散光变化的 J 向量，其中 J（通过自动折射仪）=0.287L-0.160（r=0.487，n=38，P=0.001）和 J（通过主观折射术）=0.281L-0.102（r=0.490，n=38，P=0.002），和（C）在第 2 组中，2 至 3 个月之间的 J 和 ΔΚ，其中 J（通过主观折射术）=0.086ΔΚ-0.063（r=0.378，n=26，P=0.020）。
超声乳化手术后第一主焦线相对于瞳孔中心的位置变化会导致屈光性散光的变化。然而，L 引起的诱导散光变化之间的关系并不直接。
