Department of Ophthalmology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Korea.
Department of Ophthalmology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul, 03080, Korea.
BMC Ophthalmol. 2020 Apr 28;20(1):169. doi: 10.1186/s12886-020-01439-4.
Currently, various types of toric intraocular lenses (IOL) have been manufactured and can be divided into three types according to the location of correction component; front-toric IOL (correction on anterior IOL surface), back-toric IOL (correction on posterior IOL surface), and bi-toric IOL (correction on both anterior and posterior IOL surfaces). In this study, we aimed to investigate the effectiveness of reducing corneal astigmatism of either normal or post-penetrating keratoplasty (PKP) corneas according to the type of implanted toric IOLs.
Medical records were retrospectively reviewed in 370 patients who had undergone phacoemulsification with posterior chamber toric IOL insertion (front-toric IOL, back-toric IOL or bi-toric IOL). Subjects were divided into 2 groups; subjects who had no history of corneal disease with corneal astigmatism more than 1.00 diopters (D) (G1) and subjects who received previous PKP with all corneal sutures removed and had corneal astigmatism more than 1.25 D (G2). Preoperatively intended target from SRK/T was evaluated. Refractive astigmatism and its vector analysis (J0, J45), mean numerical error (MNE) and mean absolute error (MAE) were assessed at least a month after cataract surgery.
Mean preoperative corneal astigmatisms were 2.2 D and 4.0 D in G1 and G2, respectively. There was significant reduction of mean postoperative refractive astigmatism to 0.89 D in G1 and to 2.33 D in G2. In G1, bi-toric IOL showed significantly more improved refractive astigmatism than back-toric IOL. In G2, no difference in refractive astigmatism according to toric IOL type was observed. While G2 showed no difference in MNE among toric IOLs, in G1, bi-toric IOL showed significant hyperopic shift compared to back-toric IOL. In both groups, there was no significant difference in MAE according to type of IOL. No postoperative complications were observed.
Our study suggests that all types of toric IOL are beneficial in correcting astigmatism of normal and post-PKP corneas. Noticeably, bi-toric IOL showed significantly better results in refractive astigmatism than back-toric IOL in normal cornea. However, bi-toric IOL showed a more hyperopic shift compared to back-toric IOL. Among post-PKP corneas, all types of toric IOL showed similar results.
目前已经制造出多种类型的散光型人工晶状体（IOL），可根据矫正部件的位置分为三种类型：前散光型 IOL（在前 IOL 表面矫正）、后散光型 IOL（在后 IOL 表面矫正）和双散光型 IOL（在前、后 IOL 表面同时矫正）。本研究旨在根据植入的散光型 IOL 类型，探讨对正常或穿透性角膜移植（PKP）后角膜降低角膜散光的效果。
回顾性分析 370 例接受后房型散光型 IOL 植入的白内障超声乳化术患者的病历资料（前散光型 IOL、后散光型 IOL 或双散光型 IOL）。将患者分为两组：一组为角膜散光>1.00 屈光度（D）且无角膜疾病史（G1），另一组为接受过所有角膜缝线拆除且角膜散光>1.25 D 的既往 PKP 患者（G2）。评估术前 SRK/T 预测的目标值。白内障手术后至少 1 个月评估屈光性散光及矢量分析（J0、J45）、平均数值误差（MNE）和平均绝对误差（MAE）。
G1 和 G2 的平均术前角膜散光分别为 2.2 D 和 4.0 D。G1 的平均术后屈光性散光显著降低至 0.89 D，G2 降低至 2.33 D。G1 中，双散光型 IOL 的矫正效果明显优于后散光型 IOL。G2 中，不同类型的散光型 IOL 对屈光性散光的影响无差异。G2 中，不同类型的散光型 IOL 对 MNE 无差异，但 G1 中，双散光型 IOL 与后散光型 IOL 相比表现出显著的远视漂移。两组中，IOL 类型对 MAE 无显著影响。术后无并发症发生。
本研究表明，所有类型的散光型 IOL 均有益于矫正正常和 PKP 后角膜的散光。值得注意的是，在正常角膜中，双散光型 IOL 在矫正屈光性散光方面明显优于后散光型 IOL。然而，双散光型 IOL 与后散光型 IOL 相比表现出更大的远视漂移。在 PKP 后角膜中，所有类型的散光型 IOL 均表现出相似的结果。
