LASIK术后角膜上皮植入的原因及分型

Types and causal analysis of epithelial ingrowth after LASIK

目的分析准分子激光原位角膜磨镶术(LASIK)后角膜上皮植入的原因及分型。设计回顾性病例系列。研究对象45例LASIK术后角膜上皮植入处理后随诊半年以上患者共49眼。方法分析北京协和医院门诊收治的外院转来时角膜上皮植入患者,上皮植入时间6～31天,最佳矫正视力为手动～0.6,除眼部刺激症状外,多数患者伴有不同程度的角膜瓣水肿、混浊、融解。掀开角膜瓣治疗43眼。根据上皮植入的位置、发展速度进行分类。按上皮植入距角膜中央的距离和范围分为周边型、旁中央型、中央型,分别为7眼、32眼、10眼。按照发展的速度分为进展性、稳定性、静止性,分别为31眼、4眼、4眼。主要指标LASIK术后角膜上皮植入手术史、视力、角膜瓣对合、伤口愈合情况。结果引起上皮植入的主要原因:(1)角膜上皮水肿、剥脱;(2)角膜瓣状况不良;(3)角膜瓣对合异常,分别为15眼、21眼、13眼。对视力影响程度由重到轻依次为中央型>旁中央型>周边型;进展的旁中央和中央型上皮植入超过1周者,92%可导致角膜瓣基质融解,严重影响视力。治疗方案:密切观察,原瓣掀开刮除植入上皮29眼,上皮刮除联合治疗性角膜屈光手术(PTK)14眼,非掀瓣保守观察治疗6眼。角膜瓣再次掀开者角膜伤口均一期愈合,未见再次植入病例。34眼达到了术前预期视力,7眼低于术前视力1行以内,8眼低于术前预期视力2行及其以上。结论角膜上皮和角膜瓣水肿是导致LASIK术后角膜上皮植入的主要原因,92%进展的中央型和旁中央型的上皮植入者,1周左右可致角膜瓣融解,严重影响视力。积极掀瓣刮除植入上皮和局部PTK治疗是使患者恢复视力的首选治疗手段。

Objective To analyze the causes and types of epithelial ingrowth(EI) after LASIK.Design Retrospective case series. Participants Forty five patients(49 eyes) with EI after LASIK.Methods All the patients were followed up for more than half a year. The duration of EI at the time of visit ranged from 6 days to 31 days.Best corrected visual acuity ranged from hand motion to 0.6.Despite irritation,most patients had different degrees of corneal flap edema,opacity,and melting.43 eyes were treated with lifting the corneal flaps.According to the distance to central cornea and extension of EI,there were three types including 7 eyes of the peripheral type,32 eyes of the paracentral type,and 10 eyes of the central type.According to the speed of progression,there were three types including 31 eye of the progressive type,4 eyes of the stable type,and 4 eyes of the static type.Main Outcome Measures History of EI after LASIK,visual acuity,apposition of corneal flaps,wound healing.Results Causes for EI included corneal epithelium edema and exofoliation (15 eyes),unsuccessful corneal flaps(21 eyes),and abnormal apposition of corneal flaps(13 eyes).According to the degree of visual acuity influence from severe to slight,there were the central type,paracentral type and peripheral type,respectively.If progressive paracentral and central EI lasted for more than one week,corneal flaps melting happened in 92%of cases,and visual acuities were impaired severely.Among these patients,29 eyes received corneal flap lifting and ingrowthed epithelium sweeping;14 eyes received ingrowthed epithelium sweeping combined with PTK;6 eyes received conservative observation without corneal flaps lifting.All the cornea healed after corneal flaps lifting,and there was no secondary EI.Visual acuity of 34 eyes achieved the preoperative expected visual acuity;7 eyes were one line and 8 eyes were two lines or more below the preoperative expected visual acuity.Conclusion Edema of corneal epithelium and corneal flaps are the main causes of EI after LASIK.Corneal flaps melting happen in 92%of progressive paracentral and central EI for more than one week,and visual acuities are impaired severely.The operation of corneal flaps lifting,ingrowthed epithelium sweeping,as well as PTK,is the first choice of treatment to help recovering their visual acuity.