重视准分子激光角膜屈光手术后青光眼的诊断

青光眼的患病率约为1％～2％,近视眼患者的青光眼患病率是正常人群的2～3倍。估计未来20年内,全世界将有几十万例准分子激光角膜屈光手术后患者发生青光眼。大多数研究显示角膜屈光手术后中央角膜厚度变薄和角膜层间囊样综合征使得眼压测量值降低,极易发生青光眼的漏诊;术后糖皮质激素的应用使得激素易感者眼压升高。所以,屈光手术医师应重视对准分子激光角膜屈光手术后患者的长期追踪与监测。     

以虹膜炎误诊的准分子激光原位角膜磨镶术后青光眼睫状体炎综合征一例

随着准分子激光角膜屈光手术的广泛开展,术后角膜的正常结构发生不同程度的改变,角膜厚度变薄,术后测得的眼压值不能反应真实眼压情况,某些疾病的病情易被术后眼压情况所掩盖,而导致误诊,现有1例以虹膜炎误诊的准分子激光原位角膜磨镶术后青光眼睫状体炎综合征报告如下.     

激光原位角膜磨削术在青光眼患者中的应用

激光原位角膜磨削术是否可以应用到青光眼患者是一个重要临床问题,屈光手术所造成角膜厚度和角膜曲度的改变可影响眼压的测量从而影响青光眼的诊断和治疗;在手术过程中一过性但极高的眼压可能引起视网膜神经纤维损害或视网膜中央动脉阻塞,青光眼患者或皮质类固醇敏感者屈光手术后常规应用激素类眼药水可能出现激素诱导性眼压升高。虽然如此,激光原位角膜磨削术并非青光眼手术的绝对禁忌证。本文就激光原位角膜磨削术在青光眼患者中应用的安全性以及影响作出综述。     

角膜屈光手术与青光眼(英文)

角膜屈光手术改变了角膜厚度及曲率,影响术后眼压(in-trocular pressure,IOP)的测量,但动态轮廓眼压计(dynamiccontour tonometer ,DCT)不受此影响。激光原位角膜磨镶术(LASIK)中一过性的IOP升高,增加了视神经损害的风险。同时,功能性滤过泡的存在,影响屈光手术的选择和效果,甚至可能成为手术的禁忌。术后患者使用激素点眼,还可能导致激素性青光眼,故应严密监测术后眼压,并且注意角膜瓣层间积液可能掩盖高眼压。对于已接受屈光手术的青光眼患者,药物治疗方案与其他青光眼患者基本相同。本文就角膜屈光手术对眼压测量、青光眼相关特殊检查的影响、屈光手术并发症及其治疗、手术安全性等问题进行了详细综述。     

近视眼中央角膜厚度与眼内压关系的探讨

目的:探讨近视眼患者眼压与中央角膜厚度之间的内在关系。方法:收集2008-01/2009-01在本院拟行准分子激光角膜屈光手术的394例788眼眼压、中央角膜厚度资料,按中央角膜厚度分为3组。日本NIDEKNT-2000自动非接触眼压计测量眼压(NCT),博士伦准分子激光Orbscan-Ⅱ地形图眼前节诊断系统测量角膜厚度。将所得数据用统计学方法处理,分析眼压与中央角膜厚度的关系。结果:近视眼患者中央角膜厚度与其眼压成正相关,随着角膜厚度的增加,NCT测量的眼压值升高,不同组间其差值有显著性(P<0.05)。结论:近视眼患者,中央角膜厚度薄,可能低估眼压;中央角膜厚度厚,可能高估眼压。对于角膜厚,眼压偏高的近视眼患者,应结合C/D及视野综合考虑决定是否行准分子激光角膜屈光手术。     

准分子激光屈光手术对角膜生物力学及术后眼压测量的影响

对准分子激光屈光手术后角膜生物力学的变化以及所伴随的眼压测量值的改变进行测量和定量分析,对于提高准分子激光手术的安全性和手术方式的选择都有重要的指导意义.本文对不同术式的准分子激光手术对角膜生物力学以及术后眼压测量值的影响进行了综述.     

要重视准分子激光角膜屈光手术围手术期的用药规范

随着准分子激光角膜屈光手术技术和设备的不断完善,角膜屈光手术的安全性、有效性和可预测性都有了极大的提高.目前准分子激光角膜屈光手术包括准分子激光屈光性角膜切削术(PRK)、准分子激光上皮下角膜磨镶术(LASEK)、准分子激光角膜原位磨镶术(LASIK)和全飞秒激光小切口基质透镜取出术(SMILE)等,无论哪种术式,最终目标都是为了增加术眼的舒适度和改善术眼的视觉质量.在手术技巧不断完善的情况下,围手术期用药的规范性成为提高准分子激光角膜屈光手术安全性的主要因素之一.眼科医师应严格掌握准分子激光角膜屈光术后各种常用药物的适应证和规范用法,以防发生药物相关性眼病.此外,眼科医师也应了解准分子激光角膜屈光手术后的常见并发症及其药物治疗方法,重视围手术期用药规范,提高患者的视觉质量和舒适度,减少术后并发症的发生.     

预防为主提高准分子激光角膜屈光手术的安全性

准分子激光角膜屈光手术的首要问题是安全,贯穿着准分子激光矫正屈光不正手术流程的每一个环节。本文主要从预防的角度总结准分子激光角膜屈光手术的术前、术中与术后注意事项及经验和方法,从细节做起,提高准分子激光角膜屈光手术的安全性。     

准分子激光角膜屈光手术后疱疹病毒性角膜炎的研究进展

准分子激光角膜屈光手术后并发单纯疱疹病毒（HSV）感染常可引起视力的严重损害。导致准分子激光角膜屈光手术后并发疱疹病毒感染的主要原因有：准分子激光照射和手术刺激诱发潜伏的HSV活化;术后局部长期应用糖皮质激素类滴眼液,也可是上述因素综合作用的结果。及时诊断及有效的抗病毒治疗是恢复视力的关键,血清抗体检测、病毒培养、角膜上皮刮片、组织细胞切片和Negative染色、聚合酶链反应（PCR）等实验室检测均存在一定的限制,而多重PCR可能会成为有效的实验室诊断方法。准分子激光角膜屈光手术后并发HSV感染的治疗方法主要是根据病情局部或全身应用抗病毒药物,对于术前曾有单纯疱疹病毒性角膜炎（HSK）病史的患者围手术期局部给予抗病毒药物可显著降低准分子激光角膜屈光手术后疱疹病毒感染的发生率。根据近年来国内外相关的临床研究及基础研究,对准分子激光角膜屈光手术后合并HSK的病因、诊断、治疗及预防进行综述。     

飞秒激光在眼科手术中的应用

飞秒激光具有切面平整、精准度高、损伤小及应用范围广等优点,其应用已成为近年眼屈光手术研究的热点.飞秒激光可以替代机械角膜刀,用于准分子激光角膜磨镶术制作角膜瓣,实施全程飞秒激光角膜屈光手术;还可用于老视、青光眼、白内障、角膜病等诸多方面的手术治疗.本文就飞秒激光的切削原理、临床应用以及研究进展作一综述.     

Changes in corneal thickness and curvature after different excimer laser photorefractive procedures and their impact on intraocular pressure measurements

Background Excimer laser refractive surgery alters the shape and thickness of the cornea by removing central corneal tissue with submicrometer precision. The aim of the study was to analyze the changes in central corneal thickness (CCT) and curvature before and after different excimer laser photorefractive procedures and their possible impact on intraocular pressure (IOP) estimations with Goldmann applanation tonometry. Methods Data on CCT, corneal curvature and IOP readings with Goldmann applanation tonometry before and after excimer laser photorefractive surgery were analyzed retrospectively. The data was further analyzed separately in two subgroups; the photorefractive keratectomy /laser-assisted subepithelial keratomileusis (PRK/LASEK) group and the laser in situ keratomileusis (LASIK) group. Results The overall post-operative IOP readings were significantly lower than pre-operative values. There was a significant difference in the lowering of the IOP readings between the two subgroups: LASIK caused a lower IOP reading than PRK/LASEK. Conclusion The change in corneal thickness and curvature affects the estimation of IOP with Goldmann applanation tonometry after excimer laser photorefractive surgery. The amount of reduction in IOP reading might be influenced by the specific laser surgical procedure. This is of clinical importance in the evaluation of any future glaucoma in the increasing number of patients who undergo photorefractive laser surgery.     

The corneal thickness and intraocular pressure story: where are we now?

A review of the current literature was conducted regarding the effect of corneal thickness on the diagnosis of glaucoma, and the influence of excimer laser refractive surgery on intraocular pressure (IOP) measurement with Goldmann applanation tonometry. In general, normals and primary open angle glaucoma patients have a similar distribution of corneal thickness; however, there is a wide variation, ranging from 427 to 716 micro m. Normal tension glaucoma patients have a tendency towards thinner corneas than normals; however, there is an overlap of thickness measurements of more than two-thirds in 95% of patients. There is a trend for ocular hypertensives to have thicker corneas than normals, but again there is an overlap of about one-third in 95% of patients. The general trend after excimer laser refractive surgery is for a decrease in IOP, with a mean fall in IOP measured of 0.63 mmHg per dioptre correction. There is, however, a large scatter of values with some patients having the same or lower IOP post-laser, but with other patients measuring higher pressures. Corneal thickness can influence IOP measurement by Goldmann applanation tonometry; however, the magnitude of the effect is subject to much individual variation.     

The relationship between intraocular pressure and refractive error adjusting for age and central corneal thickness

PURPOSE: To investigate the relationship between intraocular pressure (IOP) and refractive errors after adjusting for age, central corneal thickness (CCT), and other related factors. METHODS: IOP, CCT and refractive errors were measured in the right eyes of 1855 subjects, aged 40-82 years, in a cross-sectional study design. Subjects were divided into groups by refractive status: hyperopia, emmetropia, mild myopia, moderate myopia, or high myopia. With adjustments for age, CCT, blood pressure, obesity, education, hypertension, diabetes, and smoking status, IOP was estimated for each refractive status using a general linear model. RESULTS: IOP increased with advancing degrees of myopia, even after adjustment for age, CCT, and other related factors (p = 0.011). Estimated IOP of moderate myopia was significantly higher than that of emmetropia (p = 0.022). CONCLUSIONS: Our results confirm the positive association between IOP and increasing degrees of myopia. This finding would support the hypothesis that the relationship between glaucoma and myopia might be pressure mediated.     

不同近视程度及准分子激光屈光术后角膜地形图分析

目的 分析不同近视程度患者的角膜地形图及准分子激光术前、术后角膜地形图的差异,了解不同近视程度及术后角膜表面形态的改变.方法 回顾性分析2004年在我院行准分子激光屈光性手术的159例患者的角膜地形图资料,比较SRI、SAI、CLY等反映角膜表面形态的参数,采用SPSS 13.0统计软件进行统计分析.结果 不同近视程度组间角膜地形图比较示:CYL的差异有统计学意义(P＜0.05),而SRI、SAI各组间没有明显差异P＞0.05);准分子激光屈光性手术前后角膜地形图参数分析示:术后CYL、SRI、SAI均有显著变化(P＜0.01),其差异具有统计学意义.结论 不同程度的近视患者间角膜表面的规则程度、对称性没有显著差异,而散光程度随近视度数增大而有所增加.准分子激光术后角膜规则性、对称性、散光程度均有显著改变,行准分子激光术矫正屈光不正时应更加注重角膜形态的改变,以减少术后视觉质量及光学问题的发生.     

三种不同设备行屈光手术时的角膜切削误差比较

目的调查2种不同的准分子激光设备和1种全飞秒激光手术设备用于准分子激光原位角膜磨镶术（LASIK）时对中央角膜厚度切削误差的影响,探索角膜切削误差的变化规律。方法前瞻性病例对照研究。使用A型超声角膜测厚仪测量分别应用3种不同设备行手术治疗的138例（274眼）患者术前及术后1个月的中央角膜厚度。其中51例（100眼）使用Esiris机器行LASIK手术（Esiris—LASIK）,50例（100眼）使用VisxS4-IR机器行LASIK手术（Visx—LASIK组）,37例（74眼）使用VisuMax机器行SMILE手术（VisuMax—SMILE组）。所有眼按屈光度分为低、中、高度3组,分别计算中央角膜厚度及角膜切削误差,并分析切削误差与不同设备、近视程度、散光程度、角膜切削直径及手术前角膜厚度的关系。采用单样本t检验、双因素方差分析及Pearson相关进行数据分析。结果3组病例中,近视程度、术前中央角膜厚度及术前散光度对角膜切削误差均没有显著影响,设备或手术方式对角膜切削误差有显著的影响。在Esiris—LASIK组中,角膜的实际切削厚度小于预期切削厚度,差异有统计学意义（低度近视组,t=4．672,P〈0．01;中度近视组,t=10．629,P〈0．01;高度近视组,t=11．021,P〈0．01）;Visx—LASIK组中,角膜的实际切削厚度大于预期切削厚度,差异有统计学意义（低度近视组,t=3．910,P〈O．01;中度近视组,t=4．922,P〈0．01;高度近视组,t=4．807,P〈0．01）;在VisuMax—SMILE组中,角膜的实际切削厚度与预期切削厚度差异无统计学意义（中度近视组,t=1．158,P〉O．05;高度近视组,t=0．836,P〉0．05）。结论不同的手术设备会显著影响屈光手术中中央角膜厚度的切削误差。     

非接触眼压分析仪（ORA）在准分子激光手术中的应用

非接触眼压分析仪（ORA）在眼科领域的应用已经成为研究的焦点,在青光眼、白内障、遗传等方面均有涉及,其在屈光手术中的应用尤为突出。ORA在分析眼压的同时,可测算出相应的角膜生物力学参数：角膜滞后量（CH）和角膜阻力因子（CRF）,为在体测量角膜生物力学参数提供了可能。就ORA在准分子激光手术术前检查、术后随访等方面的应用进行综述。     

Refractive error and glaucoma.

PURPOSE: To study the association between refractive error, glaucoma damage and IOP in a large population. METHODS: We examined 32,918 citizens of the city of Malm?, Sweden, 57-79 years of age, searching for individuals with undetected glaucoma. Refraction was measured with autorefractors. Glaucoma damage was defined as reproducible visual field defects with the Humphrey Full Threshold 24-2 program. RESULTS: Glaucoma prevalence was clearly associated with refractive state, increasing gradually with increasing myopia. This was seen both in males and females and persisted over the full age range. Glaucoma was significantly more common in myopic than in hyperopic eyes with low IOP readings (p=0.024). The overrepresentation of glaucoma in myopic eyes declined with increasing IOP and no relationship was observed in eyes with IOP > or =31 mmHg. CONCLUSION: In this large population, the prevalence of glaucoma increased with increasing myopia. The association between myopia and glaucoma was strong at lower IOP levels, and weakened gradually with increasing IOP. Our findings indicate that myopia is an important risk factor for glaucoma and particularly for normal tension glaucoma.     

近视眼患者选择准分子激光角膜屈光手术的影响因素

目的:探讨影响近视眼患者选择准分子激光角膜屈光手术的因素。方法:2007-06/2008-05近视患者734例进行问卷调查,内容包括患者人群特征、近视及矫正的情况、手术原因及对手术相关信息的了解情况、对医疗服务的满意程度等。采用Logistic回归分析影响近视眼患者选择准分子激光角膜屈光手术的相关因素。结果:在734例咨询者中,581例患者进行了手术,153例未手术。多因素非条件Logistic回归分析结果表明患者年龄、性别、教育水平、近视时间、近视程度、获得手术信息的途径、对手术了解程度、对手术期望程度、就医环境的好坏,手术医师技术的好坏,服务满意度等因素是影响近视眼患者是否选择准分子激光角膜屈光手术的主要因素。结论:影响近视眼患者选择准分子激光角膜屈光手术的因素较多。医务人员应该合理宣传准分子激光角膜屈光手术的安全性和疗效,改善患者的就医环境,提高服务满意率,使近视患者对手术疗效有合理的期望,正确选择手术。     

提高准分子激光角膜屈光手术后角膜的安全性

自70年代至今,屈光手术经过不断的革新、改进,目前准分子激光角膜屈光手术成为矫正近视的重要方法。由于其在正常的角膜组织上通过不同方式制作各种角膜瓣后进行激光切削,因而其术后长期的安全性一直是眼科医生担心和关注的主题。本文通过比较临床应用的不同技术方法的利弊,从角膜安全性角度阐述其各自的适应证,以期为临床合理治疗提供资料。