预矫度对准分子激光角膜切削术疗效影响的自身对照研究

目的研究同一个体,不同预矫度对准分子激光屈光性角膜切削术治疗近视疗效的影响。方法双 眼近视度相差≥一２．００Ｄ的 １３６例（２７２眼）近视患者,分为低屈光度组（Ⅰ 组）和高屈光度组（Ⅱ 组）,对．ＰＲＫ术后 随访１年的裸眼视力、残余屈光度及角膜ｈａｚｅ等作统计学分析。结果ＰＲＫ术后１年,Ⅰ组及Ⅱ组的裸眼视力分 别为 ０． ６９±０． ３３和 ０． ６２±０． ３８,组间差异无统计学意义（ Ｐ ＞０．０５）;残余近视度在预矫度±０． ５０Ｄ和±１． ００Ｄ以 内者,Ⅰ组为 ７６眼（５５． ８８％）和 ９５眼（６９． ８５％）,Ⅱ组为 ４５眼（３３． ０９％）和 ７２眼（５２． ９４％）,组间差异极显著（ Ｐ ＜ ０．０１）;±２．００Ｄ以内者,Ⅰ组为９８眼（７２．２２％）,Ⅱ组为８７眼（６３．９７％）,组间差异无显著性（Ｐ＞０．０５）;角膜 ｈａｚｅ在随访的 １、３、６及 １２个月中,组间均无显著差异（Ｐ＞０． ０５）;角膜 ｈａｚｅ与切削深度两组均无显著相关关系 （ Ｐ＞０． ０５）。结论同一个体,预矫度高的一眼,ＰＲＫ术后的预测性及屈光稳定性较另一眼降低,但不显著加重角 膜ｈａｚｅ的程度;个体差异性是ＰＲＫ术后角膜ｈａｚｅ的一个重要的影响因素     

PRK术后角膜上皮下雾状混浊的相关因素分析

为探讨准分子激光角膜切削术（ｐｈｏｔｏｒｅｆｒａｃｔｉｖｅｋｅｒａｔｅｃｔｏｍｙ，ＰＲＫ）后角膜上皮下雾状混浊（ｈａｚｅ）的原因及影响因素，对ＰＲＫ后６个月时屈光度在－１．００～－１８．５０Ｄ的３１６例（６１５只眼）近视眼的ｈａｚｅ相关因素进行观察和比较。结果：ＰＲＫ后６个月时ｈａｚｅ发生率为４４．７％，１级或以上ｈａｚｅ为１３．３％。ｈａｚｅ的发生率及密度随屈光度增高而增加（Ｐ＜０．０００１），也随切削深度的增加而增加（Ｐ＜０．０００１），术前非接触眼压超过１８ｍｍＨｇ者，ｈａｚｅ的发生率和密度增加（Ｐ＜０．００５），男性较易发生ｈａｚｅ（Ｐ＝０．０００１），与年龄呈负相关（Ｐ＜０．０５）。而角膜厚度、术前戴用接触镜及散光对ｈａｚｅ的影响不显著。结论：高度近视（＞－６．０Ｄ）和过深的切削（＞８０μｍ）是引起ｈａｚｅ的主要原因。术前眼压偏高、年龄偏低对ｈａｚｅ也有明显影响。对ＰＲＫ治疗高度近视应持审     

准分子激光角膜切削术后上下浑浊的影响因素

目的 探讨准分子激光角膜切削术（ＰＲＫ）后发生上皮下浑浊（ｈａｚｅ）的影响因素。方法 ２１６眼随机分两组，分别于术后使用拂炎和艾氟龙滴眼。术后１年按不同因素将ｈａｚｅ进行统计学处理。结果 两组间ｈａｚｅ发生率比较Ｐ为０．０２８。术前不同屈光度（≤－６Ｄ与〉－６Ｄ）比较Ｐ为０．６２４。上皮智除时间（〈３０秒与〉１分钟）比较Ｐ为０．５１９。不同年龄组（≤２５岁与≥３５岁）比较Ｐ为０．３６６。结论 ＰＲ     

PRK后角膜混浊与屈光回退分析

为探讨准分子激光屈光性角膜切削术（ＰＲＫ）后,角膜上皮下雾状混浊（ｈａｚｅ）和屈光回退的相关因素,对３５６例（６２５眼）近视施ＰＲＫ随访１２个月后,按术前等值球镜屈光度分为Ａ组（≤—３．００Ｄ）,Ｂ组（－３．２５～－６．００Ｄ）,Ｃ组（－６．２５～１０．００Ｄ）和Ｄ组（＞－１０．００Ｄ）。观察各组术后视力恢复,角膜ｈａｚｅ和屈光回退情况。结果：术后裸眼视力在１．０以上的Ａ、Ｂ、Ｃ、Ｄ各组分别是８３．３３％、７４．３１％、４９．６２％和１３．７５％（Ｐ＜０．００１）;在０．８以上的各组是９５．０８％、９３．１２％、７７．０６％和３１．２５％（Ｐ＜０．００１）。屈光回退在－１．００Ｄ以上的分别是３．２８％、５．９６％、２２．９３％和４９．７５％（Ｐ＜０．００１）。角膜ｈａｚｅ在２级以上的仅在Ｃ组和Ｄ组中出现,分别为１０．５２％和１７．５０％（Ｐ＜０．００１）。结论：术后视力提高,角膜ｈａｚｅ和屈光回退与术前屈光度有关。ＰＲＫ治疗低中度近视,术后并发症轻、预测性和稳定性好,而用于治疗高度近视则应慎重。     

高度近视PRK术后两种类固醇激素治疗方案分析

为探讨ＰＲＫ术后类固醇激素治疗的最佳方案，将１６２例（３１４眼）高度近视随机分成Ａ、Ｂ两组，用类固醇激素眼液（０．１％醋酸氟美松龙，Ａｌｃｏｎｌ）点眼：Ａ组常规激素治疗，Ｂ组增强激素治疗，结果：两组间比较，术后六个月时裸眼视力≥０．５者Ａ、Ｂ两组分别为７７．１６％和８６．８２％，等值球镜屈光度值，两组分别为－１．６２±１．０４和－０．６２±１．１７Ｄ，最佳矫正视力下降１行以上者，两组分别为１１．７２％和５．２６％，以上三项Ｐ值均＜０．０５，相差有显著性。Ａ、Ｂ两组，角膜上皮下ｈａｚｅ的发生率和３级ｈａｚｅ形成的比例间未见明显差异，但Ａ组１级ｈａｚｅ占６９．１３％明显低于Ｂ组（９３．０２％），Ｐ＜０．０１，相差非常显著。激素反应性青光眼两组发生率分别为１８．５１％和２０．３９％，两组间无明显统计学差异。结论：高度近视ＰＲＫ术后增强类固醇激素治疗强度，可明显减轻术后角膜切削面的修复反应，降低上皮下ｈａｚｅ形成的密度，减少屈光回退，使ＰＲＫ术治疗高度近视的效果明显提高     

准分子激光角膜切削术后屈光度过桥的临床分析

目的 探讨ＰＲＫ术后屈光度过矫的原因。方法 报告ＰＲＫ术后屈光度过桥４例（６眼），男性１例（２眼），女性３例（４眼）。结果 术前近视屈光度－３．０￣－６．０Ｄ，术后过矫屈光度＋１．２５￣３．７５Ｄ。随访６￣１２个月。有５眼随着角膜厚度的增加，角膜表面平均屈力的提高，过矫屈光度减小，裸眼视力提高至预期值，１眼无变化。结论 认为利用ＰＲＫ术后角膜上皮及胶原组织增生致远期屈光回退，通过密切监测角膜厚度、     

准分子激光屈光性角膜切削术和激光原位角膜磨镶术治疗中低度近？…

目的：比较准分子激光屈光性角膜切削术（ＰＲＫ）和激光原位角膜磨镶术（ＬＡＳＩＫ）治疗中低度近视的临床效果。方法：中、低度近视４００例（７１０眼）,其中ＰＲＫ组３４３眼,平均屈光度－４．１８±１．２４Ｄ。ＬＡＳＩＫ组３６７眼,平均屈光度－４．７５±１．１０Ｄ。两组均于手术后１、３、６、１２个月复查视力、屈光度、角膜地形图及角膜上皮下基质混浊等并发症情况。结果：ＰＲＫ组欠矫〉－１．００Ｄ者９．０３％,     

角膜接触镜在PRK术后角膜上皮愈合中的作用

评价ＰＲＫ术后角膜接触镜在角膜上皮愈合中的作用。方法：收集本院１９９８年８月－１２月ＰＲＫ术后病例,以术后配戴角摹间１５４例为研究组,以术后涂抗生素眼膏、敷料包盖１８１例为对照组,比较两组术后上皮愈合的情况。结果：研究组,术后三天角膜上皮痊愈２９９只眼（９８．０３％）,角膜出现丝状物１只眼（０．３３％）,角膜出现膜状沉积物１１只眼（３．６３％）;对照组,术后三三角膜上皮痊愈１９６只眼（５７．４８％     

准分子激光屈光性角膜切削术和激光原位角膜磨镶术治疗中低度近视的对比研究

目的：比较准分子激光屈光性角膜切削术（ＰＲＫ） 和激光原位角膜磨镶术（ＬＡＳＩＫ） 治疗中低度近视的临床效果。方法：中、低度近视４００ 例（７１０ 眼） ,其中ＰＲＫ 组３４３ 眼,平均屈光度－４ ．１８±１．２４Ｄ。ＬＡＳＩＫ 组３６７ 眼,平均屈光度－ ４．７５±１．１０Ｄ。两组均于手术后１、３、６、１２ 个月复查视力、屈光度、角膜地形图及角膜上皮下基质混浊等并发症情况。结果：ＰＲＫ组欠矫＞ －１．００Ｄ者９．０３％ ,ＬＡＳＩＫ组为４ ．８０ ％ （Ｐ＜ ０．０１） 。角膜上皮下或层间混浊（Ｈａｚｅ）发生率：ＰＲＫ组０ 级８６ ．５９％ ,１ 级１１．３７％ ,２ 级２ ．０４％ ,３ 级以上无。ＬＡＳＩＫ组０ 级９５．１０％ ,１ 级２．４５％ ,２ 级以上无。结论：ＬＡＳＩＫ术式较之ＰＲＫ术式具有术后视力恢复快而稳定,用药少,痛苦少,并发症少,欠矫率低等优点,中低度近视治疗应首选ＬＡＳＩＫ方法治疗。     

PRK后视力回退与屈光度的关系

为研究不同屈光度患者准分子激光角膜切削术（ＰＲＫ）后的视力稳定性，对３６１例６１５眼行ＰＲＫ手术并随访６～１８个月，对术后视力回退情况分组统计分析。结果：近视回退率中低度近视组为３．２％，高度近视组为１４．４％，超高度近视组为５６．９％。结论：等值球镜－７．００Ｄ以下的近视患者视力稳定性较好，ＰＲＫ手术应该严格控制手术适应证来减少手术风险     

准分子激光屈光性角膜切削术后高透氧性角膜接触镜的应用

目的:探讨高透氧性角膜接触镜对准分子激光屈光性角膜切削术(photorefractive keratectomy,PRK)后眼刺激症状及角膜上皮愈合的影响。方法:共95例190眼PRK病例,术后随机选择一只眼戴软性亲水性高透氧的角膜接触镜,另一只眼配戴普通月抛型角膜接触镜。术后记录术眼自觉症状,观察角膜上皮愈合情况,检查术后6mo裸眼视力,同时进行haze评分。结果:高透氧角膜接触镜组术眼视物模糊、眼痛、畏光均轻于普通月抛型角膜接触镜组,两组比较差异有统计学意义(P<0.05)。高透氧角膜接触镜组平均角膜上皮愈合时间分别为3.11±2.12d,普通月抛型角膜接触镜组为4.02±2.21d,两组比较差异有统计学意义(P<0.05)。角膜上皮72h内愈合者高透氧角膜接触镜组占46%,普通月抛型角膜接触镜组占36%。术后第7d裸眼视力高于1.0者高透氧角膜接触镜组为60眼(63%),普通月抛型角膜接触镜组为48眼(51%)。术后6mo两组术后裸眼视力无显著性差异(P=0.35),两组haze发生率比较无显著性差异(P=0.55)。结论:PRK术后使用高透氧性角膜接触镜可以明显减轻术后患者的角膜刺激症状,减少患者的术后不适感,缩短角膜上皮的愈合时间。     

Effect of nepafenac sodium 0.1% on delayed corneal epithelial healing and haze after photorefractive keratectomy: retrospective comparative study

PURPOSE: To assess delayed epithelialization and corneal haze related to nepafenac ophthalmic suspension 0.1% (Nevanac) use after photorefractive keratectomy (PRK). SETTING: Private practice, Beverly Hills, California, USA. METHODS: This retrospective comparative chart review comprised 69 eyes (44 patients) that were divided into 2 treatment groups that were not statistically significantly different in age or preoperative spherical equivalent. The nepafenac group consisted of 34 eyes (22 patients) that received nepafenac 0.1%, moxifloxacin, and fluorometholone postoperatively. The non-nepafenac group included 35 eyes (22 patients) that received moxifloxacin and fluorometholone only. Patients were seen between 1 day and 5 days postoperatively for evaluation of epithelial healing and haze formation. Delayed epithelialization was defined as healing after day 5. All patients were followed for haze formation for a minimum of 3 months. RESULTS: Statistical analysis showed no difference between the nepafenac and non-nepafenac groups in delayed epithelialization (P = .61, chi-square test). Neither group had significant corneal haze. CONCLUSION: Nepafenac did not appear to delay corneal epithelial healing or contribute to haze formation after PRK.     

The Changes of TGF—α,TGF—β1 and Basic FGF Messenger RNA Expression i

OBJECTIVE: To study the mechanism of haze formation and investigate the expression changes of transforming growth factor-alpha (TGF-alpha), transforming growth factor-beta 1(TGF-beta 1) and basic fibroblast growth factor (bFGF) mRNA in corneal epithelium and stroma after photorefractive keratectomy (PRK). METHODS: Sixteen white rabbits were randomly divided into 4 groups, and PRK was performed on each eye of 12 rabbits. The haze formation was examined under a slit-lamp microscope at the 1st, 2nd and 3rd month after PRK, and the expressions of TGF-alpha, TGF-beta 1 and bFGF mRNA were detected with in situ hybridization. RESULTS: The corneal haze formed at the 1st month after PRK. The most prominent haze formation was observed at the 2nd month, and declined gradually at the 3rd month after ablation. TGF-alpha mRNA expression was presented on the normal corneal epithelium and not on the corneal stroma. TGF-beta 1 and bGFG mRNA were expressed by both corneal epithelium and stroma. The capacities for cornea tissue expression of three growth factors mRNA increased after PRK, and the peaks appeared on the 1st, 2nd month. The extent for expressions of three growth factors related proportionally to the haze formation. CONCLUSION: Three growth factors took part in promoting corneal wound healing after PRK, and might contribute to corneal haze formation and development.     

准分子激光角膜切削术与准分子激光原位角膜磨镶术角膜创口愈合的对比实验研究

比较准分子激光角膜切削术(photorefractive keratectomy,PRK)与准分子激光原位角膜磨镶术(1aser in situ keratomileusis,LASIK)后激光对角膜组织的切削效应及角膜的愈合情况,从组织学角度探讨角膜雾状混浊(Haze)及屈光度数回退的成因。方法24只新西兰白兔按预矫屈光度数随机分为-4.00 D组和-8.00 D组,每只兔右眼行PRK,左眼行LASIK。术后10d,1、3及6个月观察Haze情况并验光,每组随机处死3只兔取角膜行光镜、电镜及免疫组化检查,检测胶原Ⅲ、胶原Ⅳ、纤维连结蛋白(fibronectine,FN)及转化生长因子-β(transforming growth factor-β1,TGF-β2)的含量。结果行PRK术的右眼术后出现不同程度的Haze及屈光度数回退,其程度与预矫正屈光度数成正比。行LASIK术的左眼术后除少数角膜瓣周围半环形混浊外,手术区域角膜透明,屈光度数回退较右眼轻。-4.00 D组右眼与左眼术后屈光度数均稳定,-8.00 D组右眼较左眼屈光度数回退明显。右眼术后角膜愈合反应重,恢复慢。6个月时角膜基质仍处于修复阶段。左眼术后除形成角膜上皮栓及对应处基质轻度增生外,手术区域角膜瓣与基质床间界面清晰,无明显增生,角膜基质愈合反应轻、恢复快。术后所有兔眼角膜均有TGF-β1表达及活化,持续时间与角膜愈合时间一致。Haze及屈光度数回退组织学改变为：角膜上皮细胞增生,基底膜不成熟,前基质角膜细胞活化、增殖,新生胶原Ⅲ合成、排列紊乱,细胞外基质FN在角膜上皮下沉积。结论LASIK矫正近视尤其是高度近视优于PRK;角膜伤口愈合特别是基质愈合的反应程度,是。Haze及屈光度数回退的关键;TGF-β1是角膜愈合过程中重要调节因子,可通过介导角膜上皮一基质相互作用,调节胶原Ⅲ及FN的含量,参与瘢痕形成。     

Intact corneal epithelium is essential for the prevention of stromal haze after laser assisted in situ keratomileusis

AIMS: To determine the effect of intact corneal epithelium on stromal haze and myofibroblast cell formation after excimer laser surgery. METHODS: Denuded epithelium alone, photorefractive keratectomy (PRK), laser in situ keratomileusis (LASIK), or LASIK with denuded epithelium was performed in rabbit eyes. Postoperative anterior stromal haze was assessed employing a standard scale. Immunohistochemical methods were used to detect alpha smooth muscle actin (alpha-SMA), a marker for myofibroblastic cells, and type III collagen in subepithelial corneal tissue. RESULTS: Three weeks after surgery, the presence of alpha-SMA positive long extended and spindle-shaped stromal cells, and synthesis of type III collagen were observed in the subepithelial stromal layer corresponding to corneal haze in PRK and LASIK with denuded epithelium, but not in denuded epithelium alone and LASIK. CONCLUSION: The intact corneal epithelium may play an important part curbing subepithelial haze and differentiation of myofibroblasts in corneal wound healing.     

Mitomycin C alters corneal stromal wound healing and corneal haze in rabbits after argon-fluoride excimer laser photorefractive keratectomy.

PURPOSE: To investigate the effects of mitomycin C (MMC) on rabbit cornea wound healing after photorefractive keratectomy (PRK). MATERIALS AND METHODS: Rabbit corneas were stained with dichlorotriazinyl aminofluorescein immediately after PRK. MMC was applied to the right eye and phosphate-buffered salt solution (PBS) to the left. Corneal epithelial wound healing rate and corneal haze were examined. Ultrasound pachymetry was performed. Stromal collagen regeneration was evaluated by fluorescent microscopy. We used terminal deoxyribonucleotidyl transferase-mediated D-uridine 5'-triphosphated-digoxigenin nick-end labeling (TUNEL) assay and transmission electron microscopy (TEM) to evaluate keratocyte apoptosis. RESULTS: In eyes treated with MMC, there was no delay to the healing rate of corneal epithelial wound, and less haze 4 weeks after PRK. Ultrasound pachymetry showed thinner corneal thickness in MMC-treated eyes at week 4. Corneal stromal thickness regression was less in MMC-treated eyes observed by fluorescent microscope at week 4. Keratocyte apoptosis was noted in both MMC- and PBS-treated eyes by TUNEL assay and TEM observation. This study discovered the phenomenon that MMC prolongs keratocyte apoptosis. CONCLUSIONS: Applying MMC after PRK is an effective method to decrease haze formation and corneal stromal thickness regression in rabbit corneas. The effect may be related to MMC prolonging keratocyte apoptosis.     

The Changes of TGF-α, TGF-β_1 and Basic FGF Messenger RNA Expression in Rabbit Cornea after Photorefractive Keratectomy

Objective : To study the mechanism of haze formation and investigate the expression changes of transforming growth factor-α(TGF-α), transforming growth factor-β1 (TGF-β1) and basic fibroblast growth factor (bFCF) mRNA in corneal epithelium and stroma after photorefractive keratectomy (PRK).Methods: Sixteen white rabbits were randomly divided into 4 groups, and PRK was performed on each eye of 12 rabbits. The haze formation was examined under a slit-lamp microscope at the 1st, 2nd and 3rd month after PRK, and the expressions of TGF-α , TGF-β1 and bFGF mRNA were detected with in situ hybridization.Results : The corneal haze formed at the 1" month after PRK. The most prominent haze formation was observed at the 2nd month, and declined gradually at the 3rd month after ablation. TGF-a mRNA expression was presented on the normal corneal epithelium and not on the corneal stroma. TGF-β1 and bGFG mRNA were expressed by both corneal epithelium and stroma. The capacities for cornea tissue expression of thre     

准分子激光治疗性切削联合屈光性切削治疗伴有角膜混浊的近视眼

目的　了解准分子激光治疗性切削 (PTK)联合屈光性切削 (PRK)治疗伴有角膜混浊近视眼的方法及疗效。方法　激光加刮除去除角膜上皮 ,PTK切削混浊角膜 ,直径为 7 0mm。PRK作近视切削 ,直径为 6 0mm。对于角膜不平者术中用黏弹剂填平后再行上皮去除及PTK。PTK切削深度为影响视力的角膜混浊深度减去PRK及上皮切削厚度。结果　 5 4例 (79只眼 )伴有角膜混浊的近视眼治疗后随访 1年以上 ,术前平均屈光度数为 (- 6 73± 4 17)D ,平均最佳矫正视力为 0 6 3,角膜混浊原因包括感染、机械外伤、化学烧伤、热烧伤、手术后瘢痕及其他原因。术中PTK联合PRK平均切削深度为 (12 4 6 3± 5 3 31) μm。术后 5 0只眼 (6 3 3% )切削区角膜上皮下雾状混浊 (Haze)≤Ⅰ级 ,6 9只眼(89 9% )裸眼视力等于或超过术前最佳矫正视力 ,平均为 0 74。角膜表面较术前光滑 ,散光减轻。结论　PTK联合PRK是治疗伴有角膜混浊近视眼的一种安全有效的方法。     

兔准分子激光角膜切削术后角膜血小板源性生长因子mRNA表达的变化

研究角膜上皮下混浊形成的发生机制,检测准分子激光屈光性角膜切削术后角膜上皮和基质血小板源性生长因子表达的变化。方法新西兰白兔施行ＰＲＫ后１,２,３月用裂隙灯显微镜观察ｈａｘｅ形成情况,并用原位酸分子杂交方法,检测角膜上皮和基质ＰＤＧＦ ｍＲＮＡ的表达。结果正常角膜上皮细胞有ＰＤＧＦ ｍＲＮＡ表达,基质层无表达;ＰＲＫ后角膜上皮细胞ＰＤＧＦｍＲＮＡ表达增加,术后２月表达最强,且基质中亦有轻微表达。上     

羊膜移植对家兔PRK术后伤口愈合作用的研究

目的：观察羊膜对家兔PRK术后角膜伤口愈合反应的影响。方法：对30只家兔常规施行双眼PRK手术（－8．0D切削程序），即行羊膜移植，观察术后早期角膜切削区炎性细胞的浸润和角膜上皮愈合情况，晚期角膜成纤维细胞增生和上皮增生情况，观察haze并评分；早期测量角膜SOD活力和MDA含量，对结果进行统计学分析。结果：早期移植相炎性细胞的数目比对照组少，上皮愈合时间较短，晚期上皮增生较轻，晚期移植组成纤维细胞数目较少；移植组haze评分较低；早期移植组自由基反应产物MDA的含量较低，而SOD含量较高，差异均具有显著性。结论：羊膜能促进术后上皮愈合，减轻炎性反应和自由基反应，减少成纤维细胞增生，减轻haze的形成。