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。     

准分子激光原位角膜磨镶术眼压的变化和术后青光眼的诊断

准分子激光原位角膜磨镶术（laser in situ keratomileusis,LASIK）是矫正近视最常用的手术方式,术中和术后引起的眼压的变化和术后青光眼的诊断应当引起注意.术中形成的眼压升高,对视盘和视网膜造成潜在的危害.术后中央角膜变薄,导致眼压测量值偏低,易发生青光眼的漏诊.术后长期应用糖皮质激素药物可能引起角膜瓣下层间积液和继发性青光眼.视盘和视网膜神经纤维层检查可能对早期青光眼诊断提供一些参考.     

准分子激光原位角膜磨镶术对玻璃体视网膜的影响

准分子激光原位角膜磨镶术(LASIK)是目前应用最多的角膜屈光手术,LASIK手术中存在可对玻璃体和视网膜产生不良影响的机制,如术中眼压骤变、激光切削的冲击力等。这些是否会对近视患者本已脆弱的玻璃体视网膜产生不良影响?它们是否是术后出现的一些眼底病变的直接诱发因素?     

准分子激光角膜屈光手术与眼压

准分子激光角膜屈光手术是目前治疗屈光不正的主要手术方式,在改善视力的同时,我们更关心眼压和准分子激光角膜屈光手术的相互关系。本文就准分子激光角膜屈光手术的分类,24h眼压波动,术前、术后角膜厚度、曲率与眼压关系,高度近视合并青光眼的诊断,屈光回退及近视进展与眼压的关系,糖皮质激素性高眼压或青光眼做一综述,对眼科临床的诊断和治疗方面都具有重要意义。     

准分子激光原位角膜磨镶术对玻璃体视网膜的影响

准分子激光原位角膜磨镶术(LASIK)是目前应用最多的角膜屈光手术，LASIK手术中存在可对玻璃体和视网膜产生不良影响的机制，如术中眼压骤变、激光切削的冲击力等。这些是否会对近视患者本已脆弱的玻璃体视网膜产生不良影响?它们是否是术后出现的一些眼底病变的直接诱发因素?     

Avastin 前房内注入对治疗新生血管性青光眼的作用

目的 观察Avastin 在新生血管性青光眼治疗中的作用.方法 随机选择8例新生血管性青光眼患者,前房内注射Avastin,注射后2周视屈光介质情况行周边视网膜冷冻术、视网膜激光光凝术或白内障手术,观察患者虹膜新牛血管、视力、眼压变化及角膜内皮细胞计数情况.结果 8例患者前房内注射Avastin后3d虹膜新生血管基本消失,4例屈光介质透明的患者进行了全视网膜激光光凝术,4例患者因原有并发性白内障进行了周边视网膜冷冻术,冷冻术后半月2例患者行白内障超声乳化术,手术顺利,随诊6个月,8例患者均有效保存了眼球,眼压制好,虹膜无新生血管,角膜内皮细胞计数无减少,3例无白内障患者和2例白内障手术患者视力较术前改善.结论 Avastin 可作为新生血管性青光眼的辅助治疗方法,为新生血管性青光眼的治疗带来新的希望.     

准分子激光屈光性角膜切削术后前弹力层缺失对眼压读数的影响

目的 探讨疚分子激光屈光性角膜切削术（ＰＲＫ）后前弹力层缺搂与眼压读数下降值之间的相关性。方法 对ＰＲＫ手术８７眼为实验组,准分子激光原位角膜磨削术（ＬＡＳＩＫＬ）手术７６眼为对照组,检测术前及术后眼压、角膜厚度、２角膜屈光力,分析两组间眼压读数下降有无差别。结果 去降两组术后角膜厚度、角膜屈光力的改变对眼压读数的影响,ＰＲＫ和ＬＡＳＩＫ组眼压读数下降无显著性差异（Ｐ〉０．０５）。结论 ＰＲＫ术后     

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.     

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。     

准分子激光屈光性角膜切削术及原位角膜磨镶术患者视网膜电图的测定

本研究对分子激光角膜切削术及原位角膜磨镶术患者手术前后的视网膜电图进行测定分析。结果表明两组患者手术前后的视网膜电图差异均无显著性。由此推测,准分子激光屈光性手术中,激光切削时的冲击力及负压吸引对视风原功能均无显著性影响。     

Considerations of glaucoma in patients undergoing corneal refractive surgery

Glaucoma patients present a unique set of challenges to physicians performing corneal refractive surgery. Corneal thickness, which is modified during corneal refractive surgery, plays an important role in monitoring glaucoma patients because of its effect on the measured intraocular pressure. Patients undergo a transient but significant rise in intraocular pressure during the laser-assisted in situ keratomileusis (LASIK) procedure with risk of further optic nerve damage or retinal vein occlusion. Glaucoma patients with filtering blebs are also at risk of damage to the bleb by the suction ring. Steroids, typically used after refractive surgery, can increase intraocular pressure in steroid responders, which is more prevalent among glaucoma patients. Flap interface fluid after LASIK, causing an artificially low pressure reading and masking an elevated pressure has been reported. The refractive surgeon's awareness of these potential complications and challenges will better prepare them for proper management of glaucoma patients who request corneal refractive surgery.     

Laser refractive surgery in glaucoma patients

Glaucoma may not be an absolute contraindication to Laser-Assisted in situ Keratomileusis (LASIK), but so far it is a relative one. People who are glaucoma suspects or who have glaucoma are just as likely as any other to seek laser refractive surgery. LASIK is a popular ocular procedure, relatively pain free and it is carried out with an extremely precise computer-controlled excimer laser emission. On the other hand, glaucoma is a group of diseases manifested by optic nerve damage with visual field changes. Patients that undergo a transient but significant rise in intraocular pressure during LASIK procedure have risk of further optic nerve damage. Furthermore, steroids which are typically used after refractive surgery can increase intraocular pressure (IOP) especially in steroid responders, who are more prevalent among glaucoma patient. Glaucoma patients interested in LASIK surgery may visit a glaucoma specialist or another LASIK surgeon who has had experience with performing LASIK in glaucoma patients. PRK (photorefractive keratectomy), LASEK (laser epithelial keratomileusis) are good alternatives for glaucoma patients. Refractive surgeons might want to consider giving patients a photo of their optic nerve, or a drawing, or an objective record of their preoperative examination.     

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.     

Bilateral acute angle closure glaucoma after hyperopic LASIK correction

Acute angle closure glaucoma is unexpected complication following laser in situ keratomileusis (LASIK). We are reporting a 49-years-old lady that was presented to the emergency department with acute glaucoma in both eyes soon after LASIK correction. Diagnosis was made on detailed clinical history and examination, slit lamp examination, intraocular pressure measurement and gonioscopy. Laser iridotomy in both eyes succeeded in controlling the attack and normalizing the intraocular pressure (IOP) more than 6 months of follow-up. Prophylactic laser iridotomy is essential for narrow angle patients before LASIK surgery if refractive laser surgery is indicated.     

Laser epithelial keratomileusis in 2010 – a review

Photorefractive keratectomy, laser epithelial keratomileusis (LASEK) and Epi‐LASIK are all variants of a similar type refractive surgery involving laser on the surface of the cornea and differ mainly in management of the epithelium. Although laser in situ keratomileusis (LASIK) is currently the most popular form of refractive surgery, LASEK is the procedure of choice in some patients. We highlight potential complications of LASEK and how these may be managed. Following laser refractive surgery, corneal thickness is reduced, which has implications for intraocular pressure measurement and glaucoma screening and management. This is particularly important following surface laser procedures where no evidence of previous surgery may be visible. In the event that cataract surgery is required at a later date, correct calculation of the appropriate intraocular lens power can be difficult and it thus important that patients are given their preoperative keratometry readings and refraction. Compared with LASIK patients, those who undergo LASEK are considered to be at lower risk of corneal ectasia. Improved understanding of wound healing post LASEK and better postoperative pain management are ongoing challenges.     

Two cases of a penetrating keratoplasty with tissue from a donor who had undergone LASIK surgery.

PURPOSE: To report two cases of penetrating keratoplasty using tissue from a donor who had undergone laser-assisted in situ keratomileusis (LASIK) surgery before its transplantation. PARTICIPANTS: Two patients who had penetrating keratoplasties and received donor corneas from eyes that had previous LASIK. INTERVENTION: The two patients underwent corneal transplantation by two different surgeons who were unaware that the donor eyes had previous LASIK treatment. RESULTS: Penetrating keratoplasty was completed without complication in both cases, although a separation of the corneal lamellae was noted during surgery in one of the cases. The two patients are doing well at 5.5 months postsurgery. CONCLUSION: With the increasing popularity of laser refractive surgery, eye banks should increase their awareness and refine screening techniques to rule out refractive surgery in the donor corneas. The long-term follow-up of those patients will reveal if surgical success was compromised by prior refractive surgery.     

Optical low coherence reflectometry for noncontact measurements of flap thickness during laser in situ keratomileusis

OBJECTIVE: There is growing evidence that iatrogenic keratectasia after laser in situ keratomileusis (LASIK) for high corrections occurs more frequently than initially assumed, and that it may result from larger variation in flap thickness. DESIGN: Consecutive noncomparative case series PARTICIPANTS: Thirty-four patients who underwent LASIK for myopia and astigmatism (first treatment group) and 10 patients who received re-LASIK (retreatment group). METHODS: Central corneal thickness and thickness of the lamella during LASIK were determined by optical low coherence reflectometry (OLCR) and contact ultrasound pachymetry. MAIN OUTCOME MEASURES: Thickness of the flap and its standard deviation, as well as its correlation with age, sphere, cylinder, corneal thickness, intraocular pressure, and corneal refractive power (K-readings). RESULTS: The mean flap thickness of the first treatment group determined by OLCR was 130 +/- 29 microm; the 95 percentile was 169 microm and the 5 percentile was 86 microm. The flap thickness was not correlated with any of the investigated demographic or refractive parameters. The mean flap thickness of the retreatment group was 152 +/- 14 microm; the 95 percentile was 175 microm and the 5 percentile was 137 microm. Thus, the flap thickness of the retreatment group was significantly thicker compared with the first treatment group (P < 0.001). CONCLUSIONS: Optical low coherence reflectometry (OLCR) was shown to be an appropriate alternative to ultrasonic preoperative and intraoperative corneal pachymetry in laser assisted in situ keratomileusis. The lack of correlation between achieved flap thickness and preoperative clinical data, such as corneal thickness, corneal curvature, intraocular pressure, and refraction, emphasizes the importance of measuring flap thickness and corneal bed thickness during surgery.     

准分子激光原位角膜磨镶术后眼压测量值的分析

目的：探讨准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后眼压测量值的影响因素。方法：对238例(473只眼)近视患者行LASIK并随访1年，记录手术前后的屈光度、角膜厚度、角膜曲率和眼压(非接触式眼压计测量)并进行统计学处理。结果：LASIK术后3、6、12个月的屈光度、角膜厚度、角膜曲率及眼压测量值均较术前明显下降，差异有非常显著意义(P＜0．0001)。术前及术后各时期的眼压测量值与角膜厚度、角膜曲率均呈正相关，而与屈光度无关。结论：LASIK术后眼压测量值低于术前，角膜厚度和角膜曲率是影响眼压测量值的两个重要因素。     

角膜胶原交联联合准分子激光原位角膜磨镶术(LASIK)矫正屈光不正的临床观察

目的 观察角膜胶原交联加固联合准分子激光原位角膜磨镶术(laser-assisted in situ keratomileusis,LASIK)矫正屈光不正的疗效.方法 选取在我院行LASIK的患者为研究对象,其中行角膜胶原交联加固术联合LASIK治疗(治疗组)50例(100眼),行单纯LASIK治疗(对照组)50例(100眼),术后1周、1个月、3个月、6个月、12个月随访,对手术前后视力、屈光度、角膜内皮细胞计数、角膜透明度及术后角膜胶原交联线等进行研究.结果 两组裸眼视力均≥术前最佳矫正视力.术后各时间点屈光度治疗组与对照组比较差异均有统计学意义(均为P ＜0.05);治疗组术后12个月与术后1个月屈光度比较差异无统计学意义(t=0.021,P=0.070),对照组术后12个月与术后1个月比较差异有统计学意义(t=4.857,P =0.010).治疗组术后各时间点角膜内皮细胞计数与术前比较差异无统计学意义(F=1.163,P =0.327).治疗组术后早期均发生了角膜前基质轻度混浊.术后1个月治疗组角膜胶原交联线厚度为210.00～ 340.00(270.48±37.80) μm,约占角膜中央厚度的63％.治疗组均未发生与角膜瓣相关的并发症,对照组出现角膜瓣皱褶者3眼,角膜瓣移位者1眼.结论 角膜胶原交联加固术联合LASIK矫正屈光不正可以获得良好的术后裸眼视力,屈光度稳定,无角膜内皮细胞的丢失,术后早期出现角膜前基质轻度混浊均不响患者视力,术后效果好.