Objective: To determine the safe distance range of clear corneal incision (CCI) from the corneal limbus and how different CCI sites affect surgery efficacy and anterior segment parameters in patients undergoing phacoemulsification.
Methods: This retrospective case-control study was conducted in 44 patients (44 eyes) undergoing phacoemulsification and IOL implantation. The patients were divided into two groups with CCI distances ranging from 1 mm to 1.5 mm (group A, n= 22) and from 0.5 mm to 1.0 mm (group B, n= 22). The visual acuity, surgically induced astigmatism (SIA), corneal aberration, and anterior segment parameters were analyzed.
Results: Compared with the preoperative data, all the patients showed significant improvements in the postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), anterior chamber depth (ACD), and anterior chamber angle (ACA) after the surgery (P < 0.05). No significant differences were found between the two groups in postoperative UCVA, BCVA, SIA, total corneal aberration RMS, lower- and higher-order aberration RMS, spherical aberration (Z40), horizontal three leaf clover (Z33), vertical three leaf clover(Z3-3), horizontal coma(Z31), vertical coma(Z3-1), ACD, ACA, anterior chamber volume, or central corneal thickness (P>0.05).
Conclusions: Phacoemulsification is an effective therapy for cataract with a CCI distance range either of 1-1.5 mm or 0.5-1.0 mm. These two CCI distance ranges produce no significant differences in the visual quality following phacoemulsification, indicating that a CCI distance range of 0.5-1.5 mm can be safe for phacoemulsification.
目的: 通过比较角膜缘不同距离的透明角膜切口（CCI）对白内障超声乳化术手术疗效及眼前节参数变化的影响，探究CCI距离角膜缘的安全距离范围。
方法: 回顾性病例对照研究。纳入2017年3月~2018年7月于西安交通大学第二附属医院行白内障超声乳化联合IOL植入术的患者44例（44眼），根据术后CCI距离角膜缘的距离分为两组，A组（距离为1~1.5 mm），B组（距离为0.5~1 mm），每组各22例。评估分析两组术后视力、术源性散光（SIA）、角膜相差及眼前节参数。
结果: A、B两组术后的裸眼视力（UCVA）、最佳矫正视力（BCVA）均较术前明显提高（P < 0.05），两组术后的前房深度（ACD）较术前加深（P < 0.05），前房角度（ACA）较术前增加（P < 0.05）。A、B两组间的术后UCVA、BCVA无明显差异（P>0.05）。A、B两组间SIA无明显差异（P>0.05）。A、B两组间的术后角膜总相差RMS值、总低阶像差RMS值、总高阶像差RMS值、球差（Z40）、水平三叶草（Z33）、垂直三叶草（Z3-3）、水平慧差（Z31）及垂直慧差（Z3-1）无明显差异（P>0.05）。A、B两组间的术后ACD、ACA、前房容积（ACV）及中心角膜厚度（CCT）无明显差异（P>0.05）。
结论: CCI位置在距离角膜缘内0.5~1 mm与距离角膜缘内1~1.5 mm的白内障超声乳化术均具有较好的手术疗效，两种CCI的白内障超声乳化术视觉质量相当。结果提示角膜缘内0.5~1.5 mm是CCI的安全距离范围。
Keywords: aberration; cataract; clear corneal incision; phacoemulsification; visual quality.