Sankara Eye Hospital, Bengaluru, Karnataka, India.
Sankara Eye Hospital, Jaipur, Rajasthan, India.
Indian J Ophthalmol. 2023 Feb;71(2):535-540. doi: 10.4103/ijo.IJO_1641_22.
Angle kappa has been considered to play a role in causing glare and haloes despite accurate centration during implantation of multifocal intraocular lenses following phacoemulsification. There is a lack of substantial data regarding whether angle kappa is a constant entity or changes following ocular surgical procedures. To answer this question, in this prospective observational study, we measured change in angle kappa following phacoemulsification, and studied the ocular biometric parameters correlating with this change.
Angle kappa was measured objectively using synoptophore. Ocular Biometric parameters (Anterior Chamber Depth, Corneal White-to-White measurement, Lens Thickness, and Axial Length) using LenStar LS 900 Haag Streit Anterior Segment imaging system. outcome measures were a quantitative change in angle kappa from the preoperative value by one degree or more and observation of correlation between change in angle kappa and ocular biometric parameters. The Wilcoxin Signed Rank Test was used to determine the difference between pre-operative and post-operative measurements for angle kappa. A p-value of less than 0.05 was considered statistically significant. Pearson's correlation coefficient was employed to find the relationship between preoperative ocular biometric parameters and a change in angle kappa. A linear regression model was used to derive an equation considering corneal white-to-white measurement as the predictor and change in angle kappa as the outcome measure.
A significant change in angle kappa was recorded, and a significant correlation was found with corneal white to white measurements. This change could be predicted preoperatively, for a known corneal white to white measurement using the standard equation y=mx+c.
This study explains the possible cause of dissatisfaction among seemingly ideal patients who undergo multifocal IOL implantation and the potential for better decision-making during patient selection for multifocal IOL implantation.
尽管在白内障超声乳化术后植入多焦点人工晶状体时准确地进行了中心定位，但角kappa 仍被认为会导致眩光和晕影。关于角kappa 是否是一个恒定的实体，或者在眼部手术后是否会发生变化，缺乏实质性的数据。为了回答这个问题，在这项前瞻性观察研究中，我们测量了白内障超声乳化术后角kappa 的变化，并研究了与这种变化相关的眼部生物测量参数。
使用 synoptophore 客观测量角 kappa。使用 LenStar LS 900 Haag Streit 眼前段成像系统测量眼部生物测量参数（前房深度、角膜白对白测量、晶状体厚度和眼轴长度）。观察指标为角 kappa 术前值变化 1 度或更多，以及观察角 kappa 变化与眼部生物测量参数之间的相关性。Wilcoxin 符号秩检验用于确定术前和术后角 kappa 测量值之间的差异。p 值小于 0.05 被认为具有统计学意义。采用 Pearson 相关系数分析术前眼部生物测量参数与角 kappa 变化之间的关系。采用线性回归模型，以角膜白对白测量值为预测因子，角 kappa 变化为因变量，得出方程。
记录到角 kappa 有显著变化，与角膜白对白测量值有显著相关性。对于已知的角膜白对白测量值，可以使用标准方程 y=mx+c 预测这种变化。
这项研究解释了多焦点人工晶状体植入术后看似理想的患者不满意的可能原因，以及在多焦点人工晶状体植入患者选择中更好地做出决策的潜力。
