【作者】 李青；

【导师】 郭秀瑾；

【作者基本信息】 河北医科大学 ， 眼科学， 2013， 硕士

【摘要】 机械法准分子激光角膜上皮瓣下磨镶术（epipolis laser in situ ketatom-ileusis, Epi-LASIK）是目前表面切削屈光手术的主流术式，拓宽了近视手术矫治范围，适用于角膜较薄、角膜曲率偏高、近视度数较高、运动员或军人等有手术需求但不适合LASIK等深层角膜切削手术的患者Epi-LASIK较PRK、LASEK术后刺激症状轻，Haze发生率低，无LASIK等板层切削术制作角膜瓣引起的瓣不全、瓣碎裂、上皮植入等并发症问题，治疗近视效果安全有效。传统Epi-LASIK手术过程中完成激光切削后，复位角膜上皮瓣，即留瓣的Epi-LASIK，而国内外有些医师手术过程中有意丢弃角膜上皮瓣，即去瓣的Epi-LASIK（Off-flap Epi-LASIK）。两种不同的处理角膜上皮瓣的方式术后是否有差别，目前国内外尚无定论。Epi-LASIK手术是否制作了高活性保留了完整基底膜的角膜上皮瓣，目前国内外尚无定论。本研究通过观察Epi-LASIK角膜上皮瓣的组织学形态，及临床对比观察留瓣的Epi-LASIK和去瓣的Epi-LASIK是否有差别，为Epi-LASIK手术中角膜上皮瓣的去留提供理论依据。第一部分Epi-LASIK角膜上皮瓣组织形态学观察目的：通过光学显微镜及电子显微镜观察Epi-LASIK微型角膜上皮刀制作的角膜上皮瓣是否保留了完整的基底膜。方法：取去瓣的Epi-LASIK手术中去掉的角膜上皮瓣30例，其中10例通过光学显微镜，20例通过透射电子显微镜进行Epi-LASIK角膜上皮瓣的组织形态学观察。结果：光学显微镜下10例角膜上皮瓣均未见完整的基底膜；透射电子显微镜下20例角膜上皮瓣中2例（10%）保留了完整的基底膜，18例（90%）基底膜不连续或未见基底膜。结论：Epi-LASIK微型角膜上皮刀制作角膜上皮瓣理论上是从上皮细胞基底膜下和前弹力层之间分离，保留具有完整基底膜的有活性的角膜上皮瓣。但通过观察，临床上在Epi-LASIK实际手术操作过程中制作的角膜上皮瓣大部分都不能保留完整的基底膜。第二部分Epi-LASIK和去瓣的Epi-LASIK治疗近视的临床对比研究目的：对比观察Epi-LASIK矫正近视手术中去除或保留角膜上皮瓣两种术式术后的临床疗效,为Epi-LASIK手术中上皮瓣的去留提供理论依据。方法：将61例(122眼)行Epi-LASIK手术的近视患者，根据等效球镜分为高度近视组（≥6.0D）31例和中低度近视组（＜6.0D）30例，两组中所有患者均随机一眼行去瓣的Epi-LASIK,另一眼行留瓣的Epi-LASIK。分别对高度近视组中去瓣组和留瓣组及中低度近视组中去瓣组和留瓣组两组间的术后疼痛刺激、角膜上皮愈合时间、视力、屈光度、角膜上皮下雾状混浊（Haze）情况、角膜地形图（ISV、IVA）、高阶像差（RMSh、Coma、SA）等各项指标进行对比观察。结果：高度近视组：1.疼痛刺激症状:术后第2天、第3天去瓣组刺激症状比留瓣组轻，两组间比较有统计学差异（P＜0.05）；2.角膜上皮愈合时间：去瓣组（5.06±0.57天）角膜上皮愈合时间比留瓣组（5.58±0.99天）短，两组间比较有统计学差异（P＜0.05）；3.裸眼视力：术后1周、1个月、3个月去瓣组裸眼视力优于留瓣组，两组间比较有统计学差异（P＜0.05），术后6个月两组间比较无统计学差异（P＞0.05）。4.屈光度：术后1月个、3个月、6个月去瓣组和留瓣组间比较均无统计学差异（P＞0.05）；5.角膜上皮下雾状混浊（Haze）情况：去瓣组和留瓣组均无1级以上Haze发生，术后1个月、3个月、6个月两组间比较均无统计学差异（P＞0.05）；6.角膜地形图：术后去瓣组和留瓣组的ISV、IVA均较术前增加（P＜0.05），术后1个月、3个月、6个月去瓣组和留瓣组的ISV、IVA两组间比较均无统计学差异（P＞0.05）；7.高阶像差：术后去瓣组和留瓣组的RMSh、Coma、SA均较术前增加（P＜0.05），术后1个月、3个月、6个月去瓣组和留瓣组的RMSh、Coma、SA两组间比较均无统计学差异（P＞0.05）。中低度近视组：1.疼痛刺激：术后第2天、第3天去瓣组刺激症状比留瓣组轻，两组间比较有统计学差异（P＜0.05）；2.角膜上皮愈合时间：去瓣组（4.94±0.68天）角膜上皮愈合时间比留瓣组（5.81±0.91天）短，两组间比较有统计学差异（P＜0.05）；3.裸眼视力：术后1周去瓣组裸眼视力优于留瓣组，两组间比较有统计学差异（P＜0.05），术后1个月、3个月、6个月两组间比较无统计学差异（P＞0.05）。4.屈光度：术后1个月、3个月、6个月去瓣组和留瓣组间比较无统计学差异（P＞0.05）；5.角膜上皮下雾状混浊（Haze）情况：去瓣组和留瓣组均无1级以上Haze发生，术后1个月、3个月、6个月两组间比较无统计学差异（P＞0.05）；6.角膜地形图：术后去瓣组和留瓣组的ISV、IVA均较术前增加（P＜0.05），术后1个月、3个月、6个月去瓣组和留瓣组的ISV、IVA两组间比较均无统计学差异（P＞0.05）；7.高阶像差：术后去瓣组和留瓣组的RMSh、Coma、SA均较术前增加（P＜0.05），术后1个月、3个月、6个月去瓣组和留瓣组的RMSh、Coma、SA两组间比较均无统计学差异（P＞0.05）。结论：1高度近视组和中低度近视组中去瓣的Epi-LASIK均较留瓣的Epi-LASIK术后早期疼痛刺激症状轻，角膜上皮愈合时间短，裸眼视力恢复快。2高度近视组和中低度近视组中去瓣和留瓣的Epi-LASIK均无明显Haze发生，角膜上皮瓣的去留并未影响远期Haze的发生率。3高度近视组和中低度近视组中去瓣和留瓣的Epi-LASIK术后6个月均具有较好的裸眼视力，屈光状态稳定，两种术式术后均具有较好的视觉质量。更多还原

【Abstract】 Epipolis laser in situ ketatom-ileusis (Epi-LASIK) is the mainsurgical option in surface ablation at present. It broadens the rectifiablemyopia surgery range, and it’s suitable for the people with thin cornea, highcorneal curvature, higher myopic degree, and special occupations, such asathletes and soldiers who is not suitable to have LASIK. Compared with PRKand LASEK, there is less postoperative irritant symptoms in the Epi-LASIK,such as haze, and LASIK-related complications. Epi-LASIK is safe andeffective in the treating myopia. Traditional Epi-LASIK, named on-flapEpi-LASIK, resets the epithelial flap after the photorefractive corrections.Some surgeons suggested that procedures with discarded epithelium flapduring surgery be called as off-flap Epi-LASIK. Whether there is differencebetween the two surgery options, is still unknown both in and abroad. Whetherthe epithelial flap, dissected during the Epi-LASIK operation, is highly activeand has intact basement membrane, is still uncertain both in and abroad. Byobserving the morphology of Epi-LASIK corneal epithelial flap, andcomparing on-flap Epi-LASIK and off-flap Epi-LASIK, we try to determinewhether there are differences between them, and provide theoretical basis forour decision of Epi-LASIK operation in the future.PartⅠ The histomorphological observation of Epi-LASIK epithelial flapObjective：To investigate if there is intact basement membrane on theepithelial flap made with Epikeratoma through light microscope and electronicmicroscope observation.Methods：Thirty epithelial flaps of30cases, dissected during the off-flapEpi-LASIK operation, were collected, with10cases, observed by lightmicroscope and20cases, observed by transmission electron microscope.Results：Under the light microscope, there was no intact basement membrane in10cases of corneal flaps; by transmission electron microscopy,only2of the20epithelial flaps were observed with intact basement membraneand18flaps(90%) with discontinuous or no basement membrane.Conclusion：Epithelial flap, made with Epikeratoma, is theoreticallyseparated between epithelial basement membrane and Bowman’s layer, withcomplete basement membrane and active epithelial flap. But through ourobservation of flaps, collected during the actual operation of the Epi-LASIK,there are a large number of epithelial flaps without complete basementmembrane.PartⅡ Clinical comparison of Epi-LASIK and off-flap Epi-LASIK inthe treatment of myopiaObjectives：To compare the clinical effects of off-flap and on-flapEpi-LASIK, and to provide theoretical basis for keeping or removing cornealepithelial flap during Epi-LASIK operation.Methods：According to the equivalent spherical,122eyes of61casesmyopia patients given Epi-LASIK operation were divided into high myopiagroup(≥6.0D,31cases), low-to-moderate myopia group(<6.0D,30cases). Ineach group, one eye had off-flap Epi-LASIK, and the other eye went on-flapEpi-LASIK operation randomly. We compared the postoperative pian, cornealepithelium healing time, postoperative vision, refractive diopters, haze,corneal topographic map(ISV,IVA) and higher-order aberrations(RMSh, coma,SA) between the two groups.Results: High myopia group:1.The stimulus symptom: On the2nd and3rd day after surgeries, the stimulus pain was slighter for the ones receivingoff-flap than for others receiving on-flap，and there was statistical differencebetween the two groups(P <0.05);2.Corneal epithelial healing time: Cornealhealing time for off-flap group(5.06±0.57days) was shorter than that for theon-flap group (5.58±0.99days), and there was significant difference betweenthe two groups(P <0.05).3. The uncorrected visual acuity (UCVA): Atpostoperative1week，1month, and3months, UCVA of off-flap group wasbetter than UCVA of on-flap group, and there was statistical difference between the two groups (P <0.05). There was no statistical difference as tothe UCVA at postoperative6months (P>0.05)4. Refractive diopters: Therewas no statistical difference between off-flap group and on-flap group atpostoperative1month,3months and6months (P>0.05);5. Haze: There wasno more than level1Haze in the two groups, and no statistical differencebetween the two groups in postoperative1month,3months and6months (P>0.05);6. Corneal topographic map: Compared with preoperative states,postoperative ISV and IVA increased(P＜0.05),and no statistical differenceexisted between off-flap group and on-flap group in postoperative1month,3months and6months (P>0.05);7. High order aberration: PostoperativeRMSh, Coma, and SA of both groups rose(P＜0.05). There was no statisticaldifference between off-flap group and on-flap group (P>0.05).Low-to-moderate myopia group:1. The stimulus symptom: On the2ndand3rd day after surgeries, the stimulus pain was slighter for the onesreceiving off-flap than for others receiving on-flap，and there was statisticaldifference between the two groups(P <0.05);2. Corneal healing time: Thecorneal epithelium healing time of off-flap group(4.94±0.68days) wasshorter than that of the on-flap group(5.81±0.91days). There was statisticaldifference between the two groups (P <0.05);3.The uncorrected visual acuity(UCVA): At postoperative1week, UCVA of off-flap group was better thanUCVA of on-flap group, and statistical difference existed between the twogroups (P <0.05), but no statistical difference existed for UCVA atpostoperative1month,3months and6months (P>0.05);4. Refractivediopters: There was no statistical difference between off-flap group andon-flap group in postoperative1month,3months and6months (P>0.05);5.Haze: There were no more than level1Haze in the two groups. There wasno statistical difference between the two groups in postoperative1month,3months and6months (P>0.05);6.Corneal topographic map: Compared withpreoperative states, ISV and IVA increased(P＜0.05), but there was nostatistical difference between off-flap group and on-flap group inpostoperative1month,3months and6months (P>0.05);7.High order aberration: Postoperative RMSh, Coma, and SA of both groups rose(P＜0.05).But there was no statistical difference between off-flap group and on-flapgroup (P>0.05).Conclusion:1In both high myopia group and low-to-moderate myopia group, off-flapEpi-LASIK group had less pain in the early postoperative days, and thehealing time was shorter than that of on-flap Epi-LASIK group.2In both high myopia group and low-to-moderate myopia group, therewas low incidence of postoperative haze in both on-flap Epi-LASIK group andoff-flap Epi-LASIK group. The incidence of haze was not impacted by theexistence of epithelial flap.3In both high myopia group and low-to-moderate myopia group, thecases with off-flap Epi-LASIK operation or on-flap Epi-LASIK operation allgained good vision, and the refractive status were stable at6months aftersurgery. The two groups both had better visual quality.更多还原