Excimer Laser Refractive Surgery Research Articles

Topical administration of Oftaquix® and Tobrex® in refractive surgery

Background: Due to the growing resistance of causative microorganisms to previous generations of antibiotics and to the risk of post-op infectious complications associated with it, an efficacy and safety assessment of modern fluoroquinolones’ prophylactic topical administration appears to be reasonable. Purpose: To investigate the efficacy and safety of levofloxacin 0.5 % ophthalmic solution (Oftaquix®, Santen, Finland) topical use in modern excimer laser refractive surgery (LASIK). Material and methods: Patients were randomized into two treatment groups: Thirty two patients (64 eyes) were treated with levofloxacin 0.5 % ophthalmic solution (Oftaquix®, Santen, Finland) b.i.d. and thirty patients (60 eyes) received tobramycine 0.3 % eye drops (Tobrex®, Alcon-Couvreur, Belgium) q. t.d., both during first 7 days post-op. LASIK procedure using excimer laser MEL-80 (Carl Zeiss Meditec, Germany) and mechanical microkeratome LSK Moria Evolution-2 (Moria, France) was performed in all patients for myopia from –1.0 to –12.0 D. Patient’s age varied from 18 to 40 years (mean age 28.4±7.8). Results: During topical application of Oftaquix® and Tobrex® in our refractive surgery patients there were no topical, or systemic adverse reactions, or allergic reactions. Oftaquix® and Tobrex® had good topical tolerability. Therapeutic dosage regimen, sufficient in terms of anti-infective prophylaxis, in case of Oftaquix® was twice as low in comparison to Tobrex®. Tear film break-up time (TFBUT) preand post-op was comparable between groups. In both groups, TFBUT post-op was significantly lower compared to pre-op values (p 0.01). Tear production (Shirmer-I test) in both groups remained almost the same (p 0.05). Conclusion: Oftaquix® (Santen, Finland) ophthalmic solution is effective and safe for prevention of infectious complications after LASIK and appears to be a rational alternative to tobramycine 0.3 % eye drops (Tobrex®, Alcon-Couvreur, Belgium).

A new central–peripheral corneal curvature method for intraocular lens power calculation after excimer laser refractive surgery

To propose the central-peripheral (C-P) method, which requires no data history to calculate intraocular lens (IOL) powers for eyes that underwent laser in situ keratomileusis (LASIK), and compare the accuracy of the C-P method with other IOL formulas for eyes after LASIK. Sixteen patients with cataract (25 eyes) who underwent myopic LASIK were analysed retrospectively. The C-P method is a modified double-K method using the SRK/T formula, in which the estimated pre-LASIK keratometric power calculated from the post-LASIK peripheral anterior sagittal power (also called the axial power) is used for the Kpre in the double-K method using the SRK/T formula, and the post-LASIK anterior sagittal power is used for the Kpost. We compared the accuracy of the C-P method with other popular IOL calculation formulas for use in eyes after LASIK. The median values of the arithmetic and absolute prediction errors with the C-P method were 0.11 diopter (D) (range, -1.67 to 1.97 D) and 0.55 D (range, 0.02-1.97 D), respectively. The prediction error using the C-P method was within ±0.5 D in 48% of eyes, within -1.0 to +0.5 D in 60% of eyes, and within ±1.0 D in 68% of eyes. The C-P method resulted in a significantly higher percentage of eyes within ±0.5 D than the BESSt formula, Shammas-PL formula, true net power method, double-K method using 43.5 D for Kpre, and Feiz-Mannis method. The C-P method may be a good option for calculating IOL powers in eyes undergoing cataract surgery after LASIK when the preoperative LASIK data are unavailable.

Meta-analysis of Randomized Controlled Trials Comparing Excimer Laser and Phakic Intraocular Lenses for Myopia Between 6.0 and 20.0 Diopters

Meta-analysis of randomized controlled trials (RCTs) comparing excimer laser refractive surgery and phakic intraocular lenses (pIOLs) for the correction of myopia between 6.0 and 20.0 diopters (D). pIOLs are an alternative surgical option to excimer laser for these patients. The evidence base comparing these 2 methods has never been assessed systematically. Cochrane Eyes and Vision Group, International. We performed a comprehensive literature search using the Cochrane Collaboration methodology to identify RCTs. A meta-analysis on the results of RCTs was performed. We analyzed data for efficacy outcomes, accuracy outcomes, safety outcomes, adverse effects, and quality-of-life measures. This review included 3 RCTs with a total of 228 eyes. The range of myopia was 6.0 to 20.0 D with up to 4.0 D of astigmatism. The pIOL group was less likely to lose 2 or more lines of best spectacle-corrected visual acuity at 12 months (odds ratio, 0.35; 95% confidence interval, 0.19-0.66, P = 0.001). PIOL surgery scored more highly on patient satisfaction/preference questionnaires. The results of this systematic review show that pIOLs are safer within 1 year of follow-up compared with excimer laser surgical correction for myopia between 6 and 20 D. There is weaker evidence for superior visual quality in pIOL recipients. Further RCTs adequately powered for subgroup analysis with long-term follow-up are necessary to establish the ideal myopic range for excimer laser and pIOL treatments.

Computerized Scheimpflug densitometry as a measure of corneal optical density after excimer laser refractive surgery in myopic eyes

To evaluate changes in anterior corneal optical density and the refractive index after photorefractive keratectomy (PRK) using a rotating Scheimpflug system. Department of Ophthalmology, University Federico II, Naples, Italy. Comparative case series. Anterior corneal optical density was evaluated with a rotating Scheimpflug system at baseline and 3 months and 12 months after PRK in eyes with a refractive error between -6.00 diopters (D) and -12.00 D (study group). A control group of unoperated eyes with the same refraction range was used to calculate corneal optical density and the Gladstone-Dale constant in unoperated eyes using the Gladstone-Dale formula. In the study group, changes in the anterior corneal optical density were evaluated over time and variations in the anterior corneal refractive index were obtained using the Gladstone-Dale constant. The study group comprised 37 eyes and the control group, 200 eyes. In the study group, the mean anterior corneal optical density and refractive index, respectively, were 27.71 ± 4.39 and 1.360 ± 0.05 at baseline, 37.812 ± 12.31 and 1.491 ± 0.16 after 3 months (P<.001 compared with baseline), and 26.29 ± 4.93 and 1.341 ± 0.06 after 12 months (P=.03 compared with baseline). The mean corneal optical density in the control group was 27.71 ± 4.31 (SD), and the resultant Gladstone-Dale constant was 0.013. An early increase and a subsequent reduction in anterior corneal optical density and the refractive index were present in myopic eyes during 1 year after PRK.

Trends in refractive surgery at an academic center: 2007-2009

BackgroundThe United States officially entered a recession in December 2007, and it officially exited the recession in December 2009, according to the National Bureau of Economic Research. Since the economy may affect not only the volume of excimer laser refractive surgery, but also the clinical characteristics of patients undergoing surgery, our goal was to compare the characteristics of patients completing excimer laser refractive surgery and the types of procedures performed in the summer quarter in 2007 and the same quarter in 2009 at an academic center. A secondary goal was to determine whether the volume of astigmatism- or presbyopia-correcting intraocular lenses (IOLs) has concurrently changed because like laser refractive surgery, these "premium" IOLs involve out-of-pocket costs for patients.MethodsRetrospective case series. Medical records were reviewed for all patients completing surgery at the Wilmer Laser Vision Center in the summer quarter of 2007 and the summer quarter of 2009. Outcome measures were the proportions of treated refractive errors, the proportion of photorefractive keratectomy (PRK) vs. laser-assisted in-situ keratomileusis (LASIK), and the mean age of patients in each quarter. Chi-square test was used to compare the proportions of treated refractive errors and the proportions of procedures; two-tailed t-test to compare the mean age of patients; and two-tailed z-test to compare proportions of grouped refractive errors in 2007 vs. 2009; alpha = 0.05 for all tests. Refractive errors were grouped by the spherical equivalent of the manifest refraction and were considered "low myopia" for 6 diopters (D) of myopia or less, "high myopia" for more than 6 D, and "hyperopia" for any hyperopia. Billing data were reviewed to obtain the volume of premium IOLs.ResultsVolume of laser refractive procedures decreased by at least 30%. The distribution of proportions of treated refractive errors did not change (p = 0.10). The proportion of high myopes, however, decreased (p = 0.05). The proportions of types of procedure changed, with an increase in the proportion of PRK between 2007 and 2009 (p = 0.02). The mean age of patients did not change [42.4 ± 14.4 (standard deviation) years in 2007 vs. 39.6 ± 14.5 years in 2009; p = 0.4]. Astigmatism-correcting IOL and presbyopia-correcting IOL volumes increased 15-fold and three-fold, respectively, between 2007 and 2009.ConclusionsVolume of excimer laser refractive surgery decreased by at least 30% between 2007 and 2009. No significant change in mean age or in the distribution of refractive error was seen, although the proportion of high myopes decreased between summer quarters of 2007 and 2009. PRK gained as a proportion of total cases. Premium IOL volume increased, but still comprised a very small proportion of total IOL volume.

Six month results of 1000 eyes treated with all femtosecond (no excimer) laser refractive surgery

Six month results of 1000 eyes treated with all femtosecond (no excimer) laser refractive surgery

Real-time measurement of ArF excimer laser corneal tissue ablation rates using cross-correlation of laser waveforms

The current popularity of excimer laser refractive surgery suggests a need for continued research and refinements to further improve clinical outcomes. A fundamental limitation of current clinical systems is the lack of real-time feedback specifically addressing the laser-tissue interactions as directly related to laser ablation rates. This paper reports data to assess the feasibility of a novel approach that holds promise as a real-time feedback scheme based on comparison of the incident and reflected laser pulse waveforms, as quantified using a cross-correlation algorithm. The approach is evaluated for ablation of bovine cornea over a range of clinically relevant laser fluences. A linear relationship was observed between several cross-correlation metrics and the directly measured corneal ablation rate, yielding an average RMS predictive error of 3.9% using a 25-shot average reflected waveform. Assessment of the cross-correlation approach for single-shot ablation data revealed a brief transient corresponding to the first few laser pulses, which is attributed to a slight hydration gradient near the surface of the de-epithelialized cornea. Clinical refractive data are necessary to assess the precision of this approach for actual refractive surgery.

基于透镜阵列的眼科准分子激光光束整形与匀光系统

基于透镜阵列的眼科准分子激光光束整形与匀光系统

Decision Assistant Wizard to Standardize Optimal Outcomes in Excimer Laser Refractive Corneal Surgery

To assess a decision tree analysis system to further optimize refractive surgery outcomes. A 5-step decision tree, the Decision Assistant Wizard, based on previous experience with the SCHWIND AMARIS laser, was applied for selecting a customized refractive surgery treatment mode (aspheric aberration neutral, corneal wavefront-guided, or ocular wavefront-guided) to eliminate or reduce total aberration. Using the Decision Assistant Wizard, 6467 LASIK treatments were performed over a 30-month period; 5262 and 112 for myopic and hyperopic astigmatism, respectively, using aspheric aberration neutral (AF) profiles, 560 using corneal wavefront-guided profiles, and 533 using ocular wavefront-guided profiles. Twenty-two (0.3%) retreatments were performed overall; 18 (0.3%) and 0 (0%) after myopic and hyperopic astigmatism, respectively, using AF, 3 (0.5%) after corneal wavefront-guided profiles, and 1 (0.2%) after ocular wavefront-guided profiles. Decision Assistant Wizards may further optimize refractive surgical outcomes by providing the most appropriate ablation pattern based on an eye's anamnesis, diagnosis, and visual demands. The general principles may be applied to other laser systems; however, specifics will depend on manufacturers' specifications.

Innovations in Excimer Laser Refractive Technology – Focus on the WaveLight® EX500 Excimer Laser System

Excimer laser refractive surgery aims to correct lower order eye aberrations such as myopia, astigmatism and hyperopia by altering the shape of the corneal curvature through the ablation of corneal tissue. Early excimer systems were associated with concerns over post-operative complications, such as night-time driving problems, glare and halos. Furthermore, it was difficult to prevent or treat higher-order aberrations with these early systems (and conventional refractive surgery procedures). Innovations in excimer laser technology have led to the introduction of excimer laser systems with enhanced features, such as high repetition rates and customised ablation profiles, improving the safety and effectiveness of this type of surgery and allowing a broad range of patients to be treated, including those with higher-order aberrations. This article discusses these innovations in excimer laser refractive technology, focusing on the clinical use of the recently introduced WaveLight® EX500 Excimer Laser system.

Bevacizumab for the Treatment of Corneal Neovascularization

Corneal neovascularization (NV) is a severe complication associated with inflammatory or infectious disorders of the cornea. NV may lead to severe reduction in visual acuity and poor prognosis for corneal transplantation and excimer laser refractive surgery. Vascular endothelial growth factor (VEGF), a potent angiogenic factor, has been reported to play a major role in the pathogenesis of corneal NV. Use of an anti-VEGF antibody would seem a theoretically plausible means for treating corneal NV. Recently, bevacizumab, a humanized monoclonal antibody against VEGF, has been reported significantly to inhibit choroidoretinal NV. Several animal and human studies have also reported beneficial effects of bevacizumab against corneal NV; both topical and subconjunctival application were effective. Nonetheless, optimal dosage, route of administration, and possible complications are yet to be fully characterized. This review summarizes the relevant literature and formulates several key questions to guide future use of bevacizumab in the treatment of corneal NV.

Corneal Collagen Cross-Linking for Ectasia After Excimer Laser Refractive Surgery: 1-Year Results

To evaluate the 1-year results of corneal collagen cross-linking (CXL) in eyes with postoperative excimer laser refractive surgery corneal ectasia. Thirteen eyes of 9 consecutive patients who had undergone excimer laser refractive surgery (photorefractive keratectomy [n = 3], LASIK [n = 10]) with resultant unstable corneal ectasia underwent CXL with photosensitizing riboflavin 0.1% solution and subsequent exposure to ultraviolet radiation. Study eyes underwent complete ophthalmologic examination, endothelial specular microscopy, corneal topography, and aberrometry as well as central pachymetry and Scheimpflug-based topo/tomography preoperatively and at 3-, 6-, and 12-month intervals. Best spectacle-corrected visual acuity (BSCVA) improvement was statistically significant (P < .05) beyond 6 months after surgery (improvement of 0.1 logMAR at 1 year). Mean spherical equivalent refraction and mean refractive sphere reduction (improvement of 1.40 and 1.44 diopters [D], respectively) were statistically significant (P < .05) at 6 months postoperatively. At 1 year after CXL, mean endothelial cell count and keratometry (average SimK decrease of 2.02 D) as well as Klyce and Ambrósio indices did not deteriorate. Coma and spherical aberration did not change significantly. Mean pupil center pachymetry and corneal thickness at 0 and 2 mm from the thinnest corneal point decreased significantly. One year after surgery, CXL appears to stabilize eyes with ectasia consequent to excimer laser refractive surgery and improve BSCVA.

Outcomes of LASIK and PRK in Previous Penetrating Corneal Transplant Recipients

To evaluate the safety and efficacy of excimer laser refractive surgery in correcting refractive error in eyes that have undergone previous penetrating keratoplasty (PK). Twenty-three keratorefractive procedures on 16 eyes from 16 consecutive subjects were evaluated between 2002 and 2008. Each patient presented a previous history of a PK with subsequent postoperative myopia and astigmatism. Keratometric value, manifest refraction, best-corrected visual acuity, uncorrected visual acuity, and complications were determined. There were a total of 14 photorefractive keratectomy (PRK) procedures performed on 11 eyes and 9 laser in situ keratomileusis (LASIK) procedures performed on 5 eyes. In the PRK group, the preoperative post-PK manifest refractive spherical equivalent and cylindrical error were -6.22 +/- 6.23 diopter and 5.23 +/- 2.26 D, respectively. The PRK postoperative manifest refractive spherical equivalent and cylindrical error were -3.61 +/- 4.23 D (P=0.25) and 3.21 +/- 1.78 D (P=0.02), respectively. In the LASIK group, the preoperative post-PK manifest refractive spherical equivalent and cylindrical error were -3.05 +/- 3.29 D and 4.11 +/- 2.38 D, respectively. The LASIK postoperative manifest refractive spherical equivalent and cylindrical error were -1.51 +/- 2.02 D (P=0.24) and 2.08 +/- 1.26 D (P=0.03), respectively. There was a 2-line or greater improvement of uncorrected visual acuity in 8 of the 14 PRK treatments and 5 of the 9 LASIK treatments. There were two episodes of acute graft rejection. One of the episodes resolved with topical and oral corticosteroids, and the other episode required a repeat corneal transplantation. PRK and LASIK are effective tools in reducing surgically induced astigmatism after penetrating corneal transplantation in most patients in this case series. The reduction of astigmatism may allow improved contact lens or spectacle fitting to achieve best-corrected binocular visual acuity.

Heterozygous Avellino Corneal Dystrophy 9 Years After Photorefractive Keratectomy: Natural or Laser-Induced Accelerated Course?

To report a photorefractive keratectomy (PRK)-treated patient who first developed stromal opacities with a typical granular pattern 9 years after surgery, which was confirmed as heterozygous Avellino dystrophy by DNA analysis. A 37-year-old woman, who had undergone PRK 17 years ago, has been followed for glaucoma and corneal dystrophy. She had preoperative clear corneas in both eyes. Nine years after PRK, at the age of 29 years, 2-3 small, white, anterior stromal corneal opacities were first detected in both eyes. Seventeen years postoperatively, multiple anterior stromal corneal deposits with a dot, crumb, or snowflake appearance were noted to the same degree in both eyes. The intervening cornea was relatively clear. Her DNA was heterozygous for the R124H mutation. Slowly developing, mild corneal deposits occurred after PRK in this patient with heterozygote Avellino corneal dystrophy. Various clinical manifestations can occur after excimer laser refractive surgery in patients with Avellino corneal dystrophy.

Pachymetric Ratio No-History Method for Intraocular Lens Power Adjustment after Excimer Laser Refractive Surgery

To evaluate a new pachymetric method not requiring pre-refractive surgical data for adjusting the intraocular lens (IOL) power in eyes undergoing cataract surgery after excimer laser refractive surgery and comparing final refractive results with previously published formulas or methods. Retrospective noncomparative case series. Thirty-six eyes from 23 patients who had uneventful phacoemulsification cataract surgery after previous myopic (35) or mixed astigmatism (1) excimer laser photoablation. A new corneal ratio (Geggel ratio) method was developed to estimate the diopters (D) of previous excimer treatment or change in spherical equivalent (SE) at the corneal plane. A regression formula, 0.40 (|DeltaSE|-1), predicted the correction factor to be added to the SRK/T (Sanders, Retzlaff, Kraff) formula. The IOL results from the Geggel and Geggel-real (modified for mild myopia) method were compared with the Masket, Koch double K table, Ladas, Walter, modified Maloney, clinical history, Feiz standardized and nomogram, Latkany average and flat, Ferrara, Rosa, Savini, Jin, Shammas no-history and regression formula, Seitz, and Awwad methods. The SRK/T, Hoffer, and Holladay formulas were tested in appropriate formulas. All IOL powers were converted to refractive results using IOL(exact) equations. Mean +/- standard deviation (SD), range, absolute mean +/- SD, and percent within +/-0.5 D, +/-1.0 D, and -1.0/+0.5 D. The pachymetric technique minimizes hyperopic surprises with 92% of eyes within -1.0/+0.5 D and no overcorrections >0.5 D with the Geggel-real modification. Final refractive results with the Geggel, Geggel-real, Masket, Koch double K tables, Latkany average and flat, Savini, Shammas no-history, Seitz Holladay, Seitz Hoffer, and Awwad Hoffer all had >55% SE +/-0.5 D and >85% SE +/-1.0 D of the surgical goal. The best results with fewer hyperopic overcorrections were found in 5 methods that comprise a new consensus group: Geggel-real, Shammas no-history, Savini, Latkany flat, and Seitz Hoffer. The consensus group had 96% of eyes within -1.0/+0.5 D of the surgical goal. The Geggel-real method is a new approach requiring no historical data to determine IOL power in this ever-enlarging and challenging group of former refractive surgery patients undergoing routine cataract surgery. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

The use of the Ocular Response Analyser to determine corneal hysteresis in eyes before and after excimer laser refractive surgery

To compare corneal biomechanical parameters and two measures of intraocular pressure (IOP) in eyes before and after excimer laser refractive surgery, with the Ocular Response Analyser (ORA). Eighty normal eyes of 41 patients undergoing excimer laser refractive surgery in Birmingham, U.K. were recruited into three groups: Laser Assisted-Epithelial Keratomileusis (LASEK) (Myopes), Laser Assisted in Situ Keratomileusis (LASIK) (myopes) and LASIK (hyperopes). The preop and 3 months postop Goldmann correlated IOP (IOPg), corneal compensated IOP (IOPcc), corneal hysteresis (CH), and corneal resistance factor (CRF) were measured by the ORA. Central corneal thickness (CCT) was measured using ultrasonic pachymeter. The differences of the changes in IOPg, IOPcc, CH, CRF and CCT between the three groups were estimated. A General Linear Model was selected to investigate the influence of gender, age, initial conditions (CH, CRF, CCT, IOPcc and IOPg) and changes in CCT on the measured IOP. The differences between the mean IOPg, CH and CRF after refractive surgery were statistically significant for all three groups. The hyperopic LASIK group had a significantly smaller change compared to the other groups (which had no statistical significance). The preop IOPg, preop CH and gender were significant predictors of the changes in measured pressure and biomechanical parameters after surgery in the myopic groups only. CH and CRF were found to decrease after both myopic and hyperopic refractive surgery. CH and CRF measurement may prove important tools to clarify the role of corneal biomechanics for refractive surgery.

Pentacam and Orbscan II Measurements of Posterior Corneal Elevation Before and After Photorefractive Keratectomy

To compare the measurements of posterior corneal elevation above the best-fit sphere before and after photorefractive keratectomy (PRK) using two different technologies--Scheimpflug imaging using Pentacam (Oculus) and scanning slit combined with Placido imaging using Orbscan II (Bausch & Lomb). In a retrospective observational case series study, 60 eyes measured using Orbscan II and Pentacam before or after PRK were evaluated. The data were analyzed as three groups: preoperative, early postoperative (from 1 to 3 months after surgery), and late postoperative (> 3 months postoperatively but not exceeding 1 year). Anterior chamber depth, posterior best-fit float sphere, posterior central elevation (PCE) above the best-fit sphere, and posterior maximum elevation (PME) above the best-fit sphere in the 6.0-mm zone were analyzed. Posterior central elevation and PME values measured using Orbscan II were greater than those measured using Pentacam (P < .001). Anterior chamber depth values measured using Orbscan II were smaller than those measured using Pentacam in all three groups (P < .001). Using Orbscan II, PCE and PME values for the two postoperative groups were greater than for the preoperative group. Using Pentacam, the PCE values for the three groups were similar, and the PME values for the preoperative and late postoperative groups were similar. These findings indicate that Orbscan II measurements of posterior corneal elevation before and after excimer laser refractive corneal surgery may not be valid. Pentacam measurement showed no significant change in posterior corneal elevation from before to after excimer laser corneal surgery.

Comparison of corneal biomechanics in pre and post-refractive surgery and keratoconic eyes by Ocular Response Analyser

To compare biomechanical parameters measured by the Ocular Response Analyser (ORA) in the form of corneal hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT) in eyes before and after excimer laser refractive surgery and keratoconic eyes. Teaching Hospital and private eye clinic in Solihull, UK. Prospective case comparison of 110 eyes selected for refractive surgery and 132 keratoconic eyes. The CH and CRF of each eye was measured by the ORA. The CCT was measured using ultrasonic pachymetry. The mean preoperative (pre-op) CH for the normal refractive surgery eyes was 11.4+/-1.9 mmHg, CRF 10.0+/-1.6 mmHg and CCT 546.5+/-33.0 microm. Post-operatively CH was 9.2+/-2.1 mmHg, CRF 7.6+/-1.8 mmHg and CCT 483.1+/-40.8 microm. The values for keratoconic eyes were 9.4+/-2.2 mmHg, 7.7+/-2.6 mmHg and 488.1+/-52.6 microm, respectively. The CH, CRF and CCT decreased as the severity of keratoconic eyes increased. All these parameters showed statistically significant difference between normal eyes and keratoconic eyes. This was also the case between post-operative eyes. The biomechanical parameters measured were very similar when comparing keratoconic and post-refractive surgery eyes.

Influence of excimer laser refractive surgery on coefficient of aqueous outflow and trabecular structure

Influence of excimer laser refractive surgery on coefficient of aqueous outflow and trabecular structure

Characteristics of amniotic membrane and its application in excimer laser refractive surgery

准分子激光屈光性角膜手术是临床上最常见的矫治近视的手术方式,如何提高术后的视觉质量、减少并发症是研究的热点.由于羊膜具有独特的结构特性和生物学活性,而且来源广泛、处理相对简便,使其成为较理想的生物材料,在国内外已逐渐应用于眼科临床,特别是近年来在准分子激光屈光性角膜手术中的应用已见诸多报道.就羊膜的组织结构、特性、作用机制及近年来羊膜在准分子激光屈光性角膜手术中的应用及预后做一综述。