LASIK后角膜瓣移位的分析及处理

目的 分析LASIK后角膜瓣移位发生原因、临床特征及处理方法.方法 对17例21只眼LASIK后发生角膜瓣移位导致角膜瓣皱褶病人行裂隙灯观察、验光、角膜地形图检查和眼球像差测定,同时观察复位术后的变化.结果 本资料角膜瓣移位术后24 h内发生的有8例12只眼,均于术后次日复诊发现,与术中过度操作、薄瓣、窄蒂、术后揉搓眼球、眼睑痉挛等是高危因素;9例9只眼发生在LASIK后2～26 月,均与外伤有关.角膜瓣移位后24 h主要表现为角膜刺激症状,以视力下降、重影、视物变形、眩光、最佳矫正视力下降、眼球像差增大为主,重新角膜瓣复位后均有不同程度的改善.结论 LASIK后角膜瓣移位发生原因众多,会导致不同程度的视觉质量下降,及时正确处理是改善预后的关键.     

准分子激光原位角膜磨镶术中不全角膜瓣后角膜地形图的改变

目的探讨准分子激光原位角膜磨镶术(laser insitu keratomileusis,LASIK)中不全角膜瓣后角膜地形图的变化规律。方法回顾性研究17眼采用hansatome角膜板层刀行LASIK手术的患者,因术中不全角膜瓣而未发射激光的发生情况及不全角膜瓣后Orbscan角膜地形图、视力及屈光度的改变。结果术中不全角膜瓣的发生率为0.29%。不全角膜瓣切削前后视力、屈光度及角膜前后表面曲率均无明显改变(P>0.05)。结论LASIK术中不全角膜瓣的发生不会引起角膜地形图的改变,再次行LASIK并不影响疗效。     

LASIK角膜瓣远期异常

目的 探讨LASIK远期瓣异常的原因及处理方案。方法 自1997年3月～2000年2月外院LASIK后转来我院的瓣相相关异常病例11例14眼,男8例,女3例,平均年龄27.7岁,平均前屈光度为-10.78DS,发生时间为LASIK后3.5～14.0个月（平均7.6个月）。结果 4例为外伤后发生,表现为瓣明显水肿皱纹（2眼）,瓣缘卷起偏位（1眼）,取角膜异物后瓣缘线样混浊（1眼）;5例6眼为视网膜复位术中发生,表现为角膜水肿显著并浮起,其中1眼为眼内激光时应用三面镜后瓣水肿;1例2眼为三面镜检查后近瓣缘局限水肿带;1例2眼为补矫术中发生角膜瓣水肿。所有病例瓣相关异常均予以对症处理,偏位角膜瓣予以重新复位。视网膜复位术病例术中影响视网膜裂孔定位和冷凝的观察。结论 外伤和视网膜复位术中去上皮是引起的LASIK远期瓣相关异常的主要原因,冷静给予良好的复位、恰当的激素应用是保持角膜瓣原位透明的重要措施。     

飞秒激光制瓣LASIK手术后的角膜伤口愈合反应

任何屈光手术都会对角膜组织造成损伤，发生伤口愈合过程。飞秒激光作为新兴技术逐渐成为角膜屈光手术的主流方法，其伤口愈合过程直接影响术后早期炎症刺激及远期临床疗效。此前国内外对准分子激光引起的愈合反应已有详细的研究，但飞秒激光造成的角膜损伤及愈合过程报道较少。飞秒激光制瓣LASIK手术后早期炎症反应较机械刀制瓣LASIK术后重，并有其特点。（国际跟科纵览，2012，36：323—327）     

飞秒激光联合LASIK术后视觉质量的变化

目的：对比飞秒激光制瓣的准分子激光原位角膜磨镶术( femtosecond-laser in situ keratomileusis, femto-LASIK )与传统机械板层刀制瓣的准分子激光原位角膜磨镶术( laser in situ keratomileusis,LASIK)治疗屈光不正患者术后视觉质量的变化。
　　方法：回顾性病例研究。选择我院2014-01/2015-12进行屈光手术的患者89例178眼,其中使用飞秒激光制作角膜瓣患者46例92眼,使用显微角膜板层刀制作角膜瓣患者43例86眼。术后随访6mo,观察患者的视力、屈光状态、主观视觉质量评分、高阶像差等情况。
　　结果：所有患者均顺利完成手术,角膜瓣均制作成功,无术中及术后并发症发生。两组患者术后不同时间裸眼视力与术前最佳矫正视力相比较,差异无统计学意义(P>0.05),两组患者术后屈光度与术前预期屈光度比较,差异具有统计学意义(P<0.05)。两组患者术后6mo主观视觉调查质量评分比较,差异有统计学意义(P<0.05)。术后6 mo飞秒激光组和机械板层刀组角膜像差均方根值、球差及彗差较术前增加,差异具有统计学意义(P<0.05),但飞秒激光组增加的幅度比机械板层刀组低,差异有统计学意义(P<0.05)。
　　结论：飞秒激光制作角膜瓣更精确可靠,离散度更小,可以制作更薄的角膜瓣,飞秒激光制瓣的LASIK较传统机械板层刀LASIK术后可以获得更好的视觉质量。     

LASIK术中术后并发症及相关因素探讨

目的 探讨准分子激光原位角膜磨镶术(LASIK)术中术后并发症的最佳处理方法.方法 选择我院3年间接受LASIK术受术者1877例(3740眼)资料,对术中及术后并发症的资料进行统计,并分析其相关因素.受术者随访期均为3月余.结果 术中并发症主要为角膜瓣破损3眼(0.08%),角膜瓣游离1眼(0.03%).术后影响视力的主要并发症为角膜瓣皱褶5眼(0.14%),角膜瓣"反卷"2眼(0.05%),屈光回退201眼(5.374%).结论 避免上述有关因素,同时给予及时恰当的处理,在很大程度上可减少LASIK术中及术后相应并发症的发生.     

薄角膜瓣准分子激光原位角膜磨镶术治疗角膜移植术后屈光不正

目的探讨应用薄角膜瓣的准分子激光原位角膜磨镶术（LASIK）治疗角膜移植术后屈光不正的疗效。方法应用薄角膜瓣的LASIK技术治疗角膜移植术后屈光不正35例（35眼）。结果术后随访期间,全部角膜植片保持透明;术后6个月最佳矫正视力高于或等于术前者34眼,占97．14％;而最佳矫正视力下降1行的1眼,占2．86％;未观察到术后最佳矫正视力较术前下降2行以上的病例。结论应用薄角膜瓣的准分子激光原位角膜磨镶术治疗角膜移植术后屈光不正是安全有效的方法,可为解决角膜移植术后高度屈光不正问题带来希望。     

LASIK术后早期角膜上皮改变的共焦显微镜观察

目的 评价LASIK术后不同时间角膜中央上皮厚度变化，探讨上皮厚度变化与屈光状态之间的关系。方法 设计自身配对研究。选择2002年11月29日至2003年1月24日于天津医科大学眼科中心屈光手术门诊进行原位角膜磨镶术病例24例(48眼)，分别在术前、术后第1、3、7、10、30、60、90天，观察屈光状态的变化，应用活体共聚焦显微镜(Confoscan 3．0)测量中央角膜上皮厚度，并对上皮厚度变化与屈光状态的相关性进行分析。结果 与术前相比，LASIK术后角膜上皮厚度平均增加了10．7％。等效球镜度数变化与上皮厚度的变化呈正相关(r=0．538，P=0．047)。结论 LASIK术后角膜上皮厚度增加，上皮参与了早期角膜组织修复的过程。术后屈光状态变化与上皮厚度的增减有关。     

LASIK术中术后并发症的观察分析

目的观察准分子激光原位角膜磨镶术(excimerlaserinsitukeratomileusis,LASIK)的术中术后并发症,探讨其发生的种类,原因,处理方法及预防措施。方法对523例(1011眼)LASIK术中术后并发症的发生、发展及影响进行了6个月的观察。结果LASIK术中并发症有角角膜血管翳出血,角膜瓣不规则游离,角膜瓣偏位,角膜瓣形成不全和角膜层间异物;术后出现多种并发症如切削区明显偏位,中心岛形成,瓣下中央区感染,不规则散光,角膜瓣皱褶,角膜瓣下上皮植入,屈光过矫,欠矫,屈光回退,眩光,激素性高眼压和干眼症。多数并发症经治疗和处理后,未对视功能产生明显影响。结论LASIK治疗近视安全、有效,但存在许多并发症,应引起重视。手术技巧的提高、手术设计的完善和手术设备的改进以及有效及时处理各种并发症是保证手术成功的关键。     

准分子激光上皮下角膜磨镶术和准分子激光原位角膜磨镶术在屈光回退再治疗的疗效观察

目的比较准份子激光上皮瓣下角膜磨镶术（LASEK）和准分子原位角膜磨镶术（LASIK）在屈光回退再治疗的安全性、有效性和可预测性。方法回顾性分析8例（12只眼）LASEK（A组）和15例（23只眼）LASIK（B组）在术后屈光回退、欠矫再次手术病例。A组采用酒精浸泡保留上皮瓣的方法;B组采用原瓣掀起或再次重新制瓣的方法。结果术后1个月A组眼视力≥0.8者9只眼（占75%）,B组≥0.8者2只眼（87%）,等效球镜屈光度＋1.0～-1.25D之间。B组有1只眼重新制瓣时出现角膜瓣错位,第3次手术行LASEK裸眼视力达到1.0。结论LASEK和LASIK在术后屈光回退、欠矫再治疗是安全有效的。LASIK术后恢复快,层间反应轻,稳定性好,优于LASEK,而LASIK在角膜薄、初次手术瓣异常、高度近视再次手术等选择上优于LASIK。两种手术方法在远期疗效和术后并发症等仍需更长期的观察。     

Effect of myopic laser in situ keratomileusis on epithelial and stromal thickness: a confocal microscopy study

PURPOSE: To determine changes in central epithelial and stromal thickness in human corneas in vivo after laser in situ keratomileusis (LASIK). DESIGN: Prospective, nonrandomized, comparative trial. PARTICIPANTS: Eighteen eyes of 12 patients received LASIK (performed using the VISX Star laser [VISX, Santa Ana, CA]) with a planned 180- micro m flap (created using an automated Hansatome microkeratome [Bausch & Lomb, Irvine, CA]) to correct refractive errors between -2.0 diopters (D) and -11.0 D. METHODS: Corneas were examined by using confocal microscopy in vivo before LASIK and at 1 week and 1, 3, 6, and 12 months after LASIK. Epithelial thickness was the distance between images of the surface epithelium and subbasal nerve plexus or, when nerves were not visible, the subbasal peak (if present in the light intensity profile). Total flap thickness was the distance between images of the surface epithelium and interface debris (or peak), and total stromal thickness was the distance between images of the most anterior keratocytes and endothelium. MAIN OUTCOME MEASURES: Corneal epithelial and stromal thickness. RESULTS: Epithelial thickness before LASIK was 46 +/- 5 micro m (mean +/- standard deviation) and increased 22% by 1 month after LASIK (56 +/- 5 micro m; P = 0.01). Thereafter, epithelial thickness did not change, but remained thicker at 12 months after LASIK (54 +/- 8 micro m) than before LASIK (P = 0.02). Total flap thickness at 1 month after LASIK was 160 +/-28 micro m and did not change thereafter. Changes in total stromal thickness between 1 and 12 months after LASIK were not significant. CONCLUSIONS: The central corneal epithelium was thicker in the first year after LASIK than before LASIK. There was no change in central stromal thickness between 1 month and 12 months after LASIK.     

LASIK术后角膜基质床及全角膜厚度的变化及相关因素分析

目的:通过观察LASIK手术的患者术前、术中及术后1wk;1,3,6mo角膜厚度及屈光状态的变化,探讨LASIK术后屈光度数回退的原因及影响因素。方法:选择我院进行LASIK手术的患者856例856眼,分别测量其术前角膜厚度、术中角膜瓣及基质床厚度;术后1wk;1,3,6mo角膜厚度,观察屈光状态的变化,分析实际切削深度与预计切削深度的差异,屈光回退的可能原因。结果:实际角膜切削深度较准分子激光机显示理论角膜切削深度深22.15±7.23μm。角膜中央厚度变化在术后6mo以后趋于稳定。屈光度数回退量与年龄、角膜床厚度呈负相关,与术前屈光度呈正相关。结论:LASIK手术中实际切削深度与预计切削深度稍有差异,充分考虑这点有助于提高手术的安全性。准确掌握术中的实际切削深度是提高手术安全性的保障。     

LASIK术中两种掀瓣法对术后屈光度的影响

目的:探讨LASIK术中"干性"掀瓣法和"湿性"掀瓣法对术后屈光度的影响。方法:近视患者66例132眼,随机分为A,B两组。在LASIK操作过程中,A组31例62眼采用"干性"掀瓣法掀瓣,B组35例70眼采用"湿性"掀瓣法掀瓣。其他操作在两组中完全一致。术后3mo复查,将散瞳验光的结果转换为等效球镜度,进行对比分析。结果:A组术后等效球镜度为正值的有92.9%,为负值的有7.1%;而B组则分别为51.5%和48.5%,两组差别具有显著统计学意义(P<0.01)。结论:LASIK术中"干性"掀瓣法较"湿性"掀瓣法可致术后屈光度具有更好的一致性和可预测性。     

Late-onset laser in situ keratomileusis (LASIK) flap dehiscence during retinal detachment surgery

PURPOSE: To report a case of laser in situ keratomileusis (LASIK) flap dehiscence during retinal detachment surgery 7 months after uneventful refractive surgery. DESIGN: Interventional case report. METHODS: A 47-year-old man noticed a defect of the upper visual field in his right eye 7 months after a LASIK procedure. The fundus showed rhegmatogenous retinal detachment, and a scleral buckling procedure was performed. During the buckling procedure, the corneal flap became detached. RESULTS: At completion of the buckling procedure, the detached corneal flap was carefully raised and the exposed corneal stroma was cleansed of any residual epithelial cells or red blood cells with irrigation using balanced salt solution. One day after the operation, the LASIK flap was repositioned, the cornea had cleared, and the retina was reattached. CONCLUSIONS: As LASIK increases in popularity, the complication we have reported may become more common. We suggest that a retinal detachment surgery should be performed with careful avoidance of corneal trauma even if a long time has passed since the LASIK procedure.     

Measurement of corneal curvature change after mechanical laser in situ keratomileusis flap creation and femtosecond laser flap creation

PURPOSE: To compare the change in corneal curvature from the predicted surgical radius (sculpted in the corneal stroma) and the measured postoperative radius of the first surface of the cornea after laser in situ keratomileusis (LASIK) for myopia correction using 2 methods of flap creation: mechanical microkeratome and femtosecond laser. SETTING: Vissum-Instituto Oftalmológico de Alicante, Alicante, Spain. METHODS: This retrospective consecutive nonrandomized comparative interventional case series included 85 eyes with myopia or myopic astigmatism treated using the Esiris excimer laser (Schwind). Patients were divided into 2 groups. One group had LASIK with an M2 microkeratome (Moria) (mechanical LASIK group) and the other, with a femtosecond laser (IntraLase FS, IntraLase Corp.) (femtosecond LASIK group). The relationship between the postsurgical corneal radius and the predicted sculpted radius as well as the mean value of the percentage change in the curvature radius were analyzed to obtain the effect on the refractive defect in each group. RESULTS: There were 44 eyes in the mechanical LASIK group and 41 eyes in the femtosecond LASIK group. A high correlation was found between the final corneal radius and the predicted sculpted radius in both groups (r(2) = 0.85). The mean percentage change in the curvature radius was -3.6% in the mechanical LASIK group and -1.6% in the femtosecond LASIK group (P<.001). The mean estimated refractive change was 1.2 diopters (D) and 0.8 D, respectively. CONCLUSIONS: The refractive change in corneal curvature, which related to the biomechanical response of the corneal surface after the flap cut and repositioning, was lower after femtosecond laser LASIK than after LASIK performed using a mechanical microkeratome. Estimations of refractive change induced by this response should be taken into account in surgery design.     

飞秒激光制瓣与机械板层刀制瓣的LASIK术后临床疗效的比较

目的：比较飞秒激光制瓣的LASIK(Femto-LASIK)与经典的机械板层刀制瓣的准分子激光原位角膜磨镶术两种手术方式矫治近视患者的安全性、有效性及术后视觉质量的区别。

方法：回顾性病例对照研究,选取2016-07/2017-06在襄阳市中心医院飞秒激光中心进行板层刀制瓣-LASIK(62例124眼)或Femto-LASIK(58例116眼)手术的近视患者120例240眼。测量两种不同制瓣术式中制作的角膜瓣厚度以及术后视力、屈光状态及角膜地形图参数和像差等并进行比较。

结果：所有患者角膜瓣均制作成功,并且都顺利地完成了手术,术中及术后无明显的并发症发生。术后两组间患者的裸眼视力、屈光度差异无统计学意义(P>0.05)。术中Femto-LASIK组制作的角膜瓣厚度与预设差值小于板层刀制瓣-LASIK组(t=26.67,P<0.01),且球差、彗差和总高阶像差增幅均小于板层刀制瓣-LASIK组(t=-4.16、-4.92、-22.19,均P<0.01)。板层刀制瓣-LASIK组和Femto-LASIK术后角膜表面规则指数(SRI)分别为0.31±0.09、0.25±0.04,二者比较差异有统计学意义(t=6.59,P<0.01)。

结论：飞秒激光制作角膜瓣比板层刀制瓣较为精确,并且术后角膜的像差相对较小,飞秒激光制瓣可提供相对较好的视觉质量,但是这两种制瓣方式术后患者的裸眼视力和屈光状态无明显差异。     

Corneal healing after uncomplicated LASIK and its relationship to refractive changes: a six-month prospective confocal study

PURPOSE: To investigate corneal healing and the factor(s) possibly responsible for refractive changes after laser in situ keratomileusis (LASIK). METHODS: Twenty eyes of 10 patients who underwent LASIK for myopia were examined clinically and by real-time confocal microscopy for 6 months. Epithelial and posterior stromal thicknesses and the thickness of the keratocyte activation zone were measured, and refractive changes were compared with these values. Keratocyte morphology, flap thickness, and subbasal nerve fiber bundle morphology after LASIK were also investigated. RESULTS: No significant change was detected over time in epithelial thickness after LASIK treatment; however, the posterior stromal thickness was found to be significantly higher 1 month after surgery. A slight but statistically significant negative correlation was detected between the thickness of the keratocyte activation zone and the spheroequivalent refraction after LASIK. The subbasal nerve fiber bundle's morphology returned to its preoperative appearance 6 months after LASIK, but in the flap stroma the nerve fiber bundle morphology remained abnormal at 6 months after LASIK surgery. CONCLUSIONS: A weak but significant negative correlation between the thickness of the keratocyte activation zone and spheroequivalent refraction was found after LASIK. The different refractive properties of activated keratocytes may be responsible for the myopic shift after LASIK. Further studies are needed to clarify this hypothesis.     

Induced optical aberrations following formation of a laser in situ keratomileusis flap

PURPOSE: To determine how refractive error, visual acuity, and high-order aberrations (3rd- and 4th-order) are affected by the formation of a lamellar corneal flap during laser in situ keratomileusis (LASIK). SETTING: University refractive surgery center. METHODS: The effect of lamellar corneal flap formation was analyzed in 15 myopic eyes (mean preoperative refraction -4.72 diopters [D] [range -1.25 to -7.25 D]). The flap was created using a 2-step procedure: (1). a nasally hinged lamellar corneal flap was created; (2). the flap was lifted and stromal ablation performed 2 months after the flap was made. A Hartmann-Shack aberrometer was used to measure the aberrations. RESULTS: There was no significant change in the refractive error (spherical equivalent pre-flap -4.72 +/- 1.99 D and post-flap -4.62 +/- 1.99 D [P =.28]) or visual acuity (pre-flap uncorrected visual acuity [UCVA] 0.07 and best corrected visual acuity [BCVA] 0.96; post-flap UCVA 0.08 and BCVA 0.95 [P =.16 and P =.33, respectively]). A statistically significant increase in total higher-order wavefront aberrations was observed following flap formation (root mean square pre-flap 0.344 +/- 0.125 and post-flap 0.440 +/- 0.221 [P =.04]). CONCLUSION: Flap formation during LASIK can modify the eye's existing natural higher-order aberrations (especially spherical and coma-like aberrations along the axis of the flap's hinge), while visual acuity and refractive error remain unaffected.