Objection To compare the effects of three mainstream surgical methods on the ocular surface and investigate the optimal corneal myopia correction surgery. Methods We selected 118 patients (236 eyes) undergoing small incision lamellar extraction (SMILE) (40 patients, 80 eyes), femtosecond-laser in situ keratomileusis (FS-LASIK) (36 patients, 72 eyes) or sub-Bowman keratomileusis (SBK) (42 patients, 84 eyes) surgery for corneal myopia correction from March 2015 to January 2016. Before surgery, one week and one month after surgery, tear film rupture time, tear river height and eye red index were measured using ocular surface analyzer. The Schimer Ⅰ test was used to detect tear secretion. Corneal sensory gauge was used to measure corneal sensation. Analysis of variance was used to analyze the measurements of the three surgical methods at various time points. Results The tear film rupture time of the three groups decreased after one week (P<0.05), but the time in the SMILE group [(9.643±4.751) seconds] was longer than those in the other two groups [FS-LASIK (8.172±4.300) seconds, SBK (7.612±3.691) seconds,P<0.05]. The time in the SMILE group at one month after surgery was not different from that before surgery (P>0.05). At one month after surgery, the rupture times of the other two groups were still shortened (P<0.05). The tear river heights in the three groups were decreased at one week and one month after surgery (P<0.05), except FS-LASIK group (P>0.05). In the SBK group, at one week after surgery, the decrease of the height was the most obvious (P<0.05). There was no difference in eye red index among the three groups at the time of observation (P>0.05). Corneal sensation decreased in the three groups at one week and one month after surgery. In the SBK group, that was the most obvious decline (P<0.05). In the three groups, the tear secretion did not change at each observation time point (P>0.05). Conclusion In the three surgical methods, SMILE has the minimal impact on the ocular surface, followed by FS-LASIK, and SBK has the greatest impact.
【摘要】目的评价双氯芬酸钠滴眼液在准分子激光上皮下角膜磨镶术(LASEK)中的临床应用价值。方法2008年7月2009年3月行LASEK术患者80例160眼,屈光度范围-4.86D±2.15D(-1.25D～-6.50D),随机分为双氯芬酸钠滴眼液组(试验组)和对照组,对两组术后角膜刺激症状、上皮愈合情况进行对比观察和统计学分析。结果试验组术后第1、3天角膜刺激症状明显轻于对照组(P＜0.05),上皮愈合速度较对照组更快(P＜0.05)。结论在LASEK术中合理使用双氯芬酸钠滴眼液,可明显减轻术后患者角膜刺激症状,促进角膜上皮的更快愈合。
The decrease of corneal stiffness is the key factor leading to keratoconus, and the corneal collagen fiber stiffness and fiber dispersion are closely related to the corneal biomechanical properties. In this paper, a finite element model of human cornea based on corneal microstructure, namely collagen fiber, was established before and after laser assisted in situ keratomileusis (LASIK). By simulating the Corvis ST process and comparing with the actual clinical results, the hyperelastic constitutive parameters and corneal collagen fiber stiffness modulus of the corneal material were determined before and after refractive surgery. After LASIK, the corneal collagen fiber stiffness modulus increased significantly, and was highly correlated with central corneal thickness (CCT). The predictive relationship between the corneal collagen fiber stiffness modulus and the corresponding CCT before and after surgery was: k1 before = exp(9.14 − 0.009CCTbefore), k1 after = exp(8.82 − 0.008CCTafter). According to the results of this study, the central corneal thickness of the patient can be used to estimate the preoperative and postoperative collagen fiber stiffness modulus, and then a personalized corneal model that is more consistent with the actual situation of the patient can be established, providing a theoretical reference for more accurately predicting the safe surgical cutting amount of the cornea.
目的:通过应用护理程序于准分子激光原位角膜磨镶术,使护理行为标准化,程序化,系统化,减少由于护理问题引发的手术并发症。方法:将100例患者随机分为常规组和程序组,分别对其实施单纯性健康宣教法和模拟训练,实地参观为一体的护理程序法,从评估,诊断,计划,实施,评价,五个方面科学实施,最终从焦虑指数,术中配合,术后满意率三个方面对两组效果进行评估。结果:常规组焦虑指数的SAS评分为42.49±1.63,程序组为32.78±1.56,两者之间有显著差异(t=9.89,Plt;0.01);术中常规组头位改变率13.27%(13/98),眼位变化率16.33%(16/98),程序组分别为3.06%(3/98)、2.04%(2/98),两者之间有显著差异(χ2=15.18,Plt;0.01);常规组术后7天裸眼视力大于或等于最佳矫正视力的常规组75眼(76.53%),程序组95眼(96.94%),两者之间有显著差异(X2=14.65,Plt;0.01)。结论:护理程序的实施规范了护士对准分子激光原位角膜磨镶术的全程护理,取得了较好的临床效果。
目的 探讨聚乙二醇滴眼液对准分子激光上皮下角膜磨镶术（LASEK）后角膜雾状混浊（haze）影响的临床研究。 方法 回顾性分析2009年3月－2010年3月行LASEK的患者45例90只眼的临床资料。患者屈光度（?4.68 ± 2.30）D（?1.75～?6.50 D），随机分为聚乙二醇滴眼液组（试验组）和对照组，术后定期随访观察两组角膜haze形成、角膜上皮愈合时间、视力恢复情况及屈光度。 结果 术后1、3、6个月，两组haze形成差异无统计学意义（P＞0.05），试验组术后第1、3、5天角膜刺激症状明显轻于对照组（P＜0.05），上皮愈合速度较对照组更快（P＜0.05）。 结论 LASEK术后应用聚乙二醇滴眼液虽然能减轻术后患者角膜刺激症状,能促进角膜上皮更快愈合，但是不能减轻haze的形成。
ObjectiveTo evaluate the effectiveness of using a six-dimensional eye-tracking system during femtosecond laser-assisted sub-Bowman keratomileusis (FS-SBK) surgery to correct myopia and astigmatism. MethodsA total of 23 patients (36 eyes) with ametropia undergoing FS-SBK were retrospectively analyzed and divided into the static cyclotorsion control (SCC) group (11 patients, 20 eyes) and the non-SCC group (12 patients, 16 eyes). According to the static eyeball rotation degrees, the SCC group was further divided into three subgroups: within ±2° group (5 patients, 9 eyes), ±2°-±5° group (4 patients, 7 eyes), and above ±5° group (2 patients, 4 eyes). The preoprative and postoperative one-month uncorrected visual acuity, best corrected visual acuity, diopter of spherical power, diopter of cylindrical power, corneal curvature, and the rotating degree in SCC were observed; the root-mean-square values of the total higher-order aberrations, spherical aberration, coma, Strehl ratio, etc. when the pupil diameter was 6.5 mm were extracted; and the therapeutic efficacy was observed. ResultsNo severe intraoperative or postoperative complications occurred in any subject. The effectiveness index of the SCC group was 0.947±0.145, and that of the non-SCC group was 1.005±0.141, with no statistically significant difference (P>0.05). Compared with the preoperative levels, in the two groups, the postoperative uncorrected visual acuity was significantly elevated; the postoperative diopter of spherical power, diopter of cylindrical power, and corneal curvature difference were reduced; the postoperative total higher-order aberrations, spherical aberration, and coma increased; all the differences mentioned above were statistically significant (P<0.05). In the SCC group, the difference between the preoperative and the postoperative Strehl ratio was statistically significant (P<0.05). There was no significant difference in postoperative indicators between the SCC group and the non-SCC group (P>0.05). The difference in postoperative increment of coma between the SCC group and the non-SCC group was statistically significant (P<0.05). In the SCC group, no statistically significant difference was found in postoperative increment of any indicator among the three subgroups (P<0.05). ConclusionsFS-SBK of six-dimensional eye-tracking system is effective in correcting myopia and astigmatism. FS-SBK can reduce lower-order aberrations while introducing higher-order aberrations, and whether SCC is performed intraoperatively is meaningless.
Objectives To assess the clinical effectiveness of laser in situ keratomileusis (LASIK) versus laser epithelial keratomileusis (LASEK) for the correction of myopia. Methods Randomised controlled trials (RCTs) were searched in PubMed, EMbase, The Cochrane Library (Issue 2, 2010), CNKI, VIP, and WangFang Data from January, 1990 to October, 2010. The RCTs were included in accordance with the Cochrane review’s methodology, the valid data were extracted, the quality was evaluated, and then the RevMan 5.0 software was used for statistical analyses. Results Seven RCTs involving 1 134 eyes with myopia were included. The results of meta-analyses showed that the efficacy (OR=1.23, 95%CI 0.73 to 2.07), accuracy (OR=1.73, 95%CI 0.74 to 2.53) and safety (OR=1.10, 95%CI 0.22 to 5.59) outcomes between LASIK and LASEK were comparable. Compared with LASIK, LASEK was higher in the incidence rate of postoperative eye pain (RR=0.13, 95%CI 0.08 to 0.22). Conclusion LASIK and LASEK have the same effectiveness for myopia, but LASEK induces more postoperative eye pains. A large number of strictly-designed multi-centred RCTs are required for further verifying this result because of the low quality and instable results of the included studies．