角膜地形图在LASIK术中作用

目的分析角膜地形图在准分子激光原位角膜磨镶术（LASIK）前后形态变化及其与临床效果的关系。方法Eyesys计算机辅助角膜地形图对150例（294眼）施行LASIK术前术后进行榆杏．结果术前对称仆对称领结型较多，共190眼（64．63％）：圆形椭圆形次之，共91眼（30．95％）；不规则形13眼（4．42％）。术后1、3、6月以圆形椭圆形居多，且相对稳定，随术后时间延长形态变化不明显，并以这部分患眼视力最好。术后6月246眼圆形椭圆形类型中229眼（93．09％）裸眼视力≥1．0。结论LASIK术前术后角膜地形图检查对适应证选择、手术参数设计、术后效果评价具有重要的指导作用。     

角膜地形图引导的传导性角膜成形术治疗兔眼LASEK术后角膜散光的实验研究

目的评估角膜地形图引导的传导性角膜成形术（CK）治疗兔眼准分子激光上皮下角膜磨镶术（LASEK）术后的中、低度角膜散光的效果。方法正常新西兰大白兔15只（30眼）制作LASEK术后角膜散光模型。其中的中、低度散光22眼（中度散光组14眼,低度散光组8眼）在角膜地形图引导下行CK治疗。结果经CK治疗后,中、低度散光组的平均角膜散光度较术前明显减少（P〈0．05）;各组术后1周、1月、3月间散光度数无差异（P〉0．05）。结论角膜地形图引导的CK对矫正LASEK术后的中、低度角膜散光是安全、有效的。     

准分子激光上皮下角膜磨镶术(LASEK)后角膜地形图分析

目的：分析准分子激光上皮下角膜磨镶术(LASEK)后角膜地形图的变化。方法：采用Orbscan Ⅱ角膜地形图仪对31例(62只眼)近视患者LASEK术后随访6个月。结果：术后6个月时切削形态中平滑型占95．2％，其他各型占4.8％，随着时间的延长，切削形态逐步规则。Irreg值也逐渐减小，而模拟角膜镜读数(SimK)却表现一定的回退。结论：LASEK后角膜及切削形态较规则，但仍然存在屈光回退的问题，角膜地形图对分析LASEK后角膜的变化是一种有效的工具。     

LASEK治疗近视疗效观察

目的　评价LASEK治疗近视的早期疗效。方法　对41例(81眼)不同屈光度(-2 . 75D～-14 . 0 0D)的近视进行LASEK手术,观察术中术后并发症,并对术后1～6月裸眼视力、屈光状态及角膜上皮下雾状浑浊(haze)进行随访。结果　2例(4眼)Ⅰ级haze ,3月时视力低于术前矫正视力1～3行,为轻度近视状态(-0 . 75D～-3 . 2 5D)。1例(2眼)Ⅱ级haze ,3月视力下降,屈光回退。6月回退到术前屈光状态。其余病例6月时视力均在0 . 5以上,达1 0者62眼占总复诊人数(76眼)的81 . 5 8%。屈光稳定于±1 . 0D以内,haze 0～0 . 5级者70眼占复诊人数(76眼)的92 . 11%。结论　LASEK是治疗近视有效方法之一,但也存在明显并发症。     

中低度近视的准分子激光上皮瓣下角膜磨镶术

目的探讨准分子激光上皮瓣下角膜磨镶术(LASEK)治疗中低度近视的疗效与安全性。方法应用德国ZeissMEL80准分子激光器对<-6.00D的中低度近视患者102例200眼施行LASEK术,术前平均裸眼视力0.17±0.13(0.02～0.6),平均等值球镜-3.87±1.57D。前瞻性地随访6个月,观察术后症状、裸眼和最佳矫正视力、显然屈光度、眼压、角膜愈合程度和并发症。结果LASEK术后6个月裸眼视力≥0.6者占100%,裸眼视力≥1.0者占96%。术后平均裸眼视力1.08±0.23,平均等值球镜-0.35±0.41D。平均角膜上皮愈合时间1～5天。术后10眼(5%)出现haze,0.5级8眼,1.0级2眼。1例患者出现眩光。结论LASEK是一种安全、有效的治疗中低度近视的屈光手术。     

青少年近视眼角膜地形图的临床分析

目的探讨青少年近视眼角膜地形图特点.方法对236例463眼青少年近视眼患者采用日本TopconKR-7100P角膜彩色地形图自动验光仪进行检测,对检测结果进行统计分析.结果①463眼角膜地形图中圆形67眼,占14.47%;椭圆形35眼,占7.56%;不规则形16眼,占3.46%;各种蝴蝶结形角膜地形图共有345眼,占总眼数73.92%.②各种角膜地形图眼的屈光度、角膜厚度、角膜直径、眼轴、眼压等差异均无统计学意义.③蝴蝶结形组与圆形角膜地形图组比较,其角膜垂直K值、角膜散光度、总散光度差异有统计学意义(P＜0.01).结论①青少年近视患者的各种角膜地形图形态与其角膜屈光度、角膜直径、角膜厚度、眼压等无明显差异.②当角膜有散光时,地形图可呈现蝴蝶结形,蝴蝶结形的轴向与角膜循散光、逆散光、斜轴散光轴向相符合.     

LASIK术前应用Pentacam分析角膜后表面地形图与术后视力改善的关系探讨

目的:应用Pentacam系统对近视LASIK术前角膜后表面地形图分析,探讨地形图与术后视力情况的关系。方法:应用Pentacam眼前节分析仪对患者术前进行表面地形图分析,观察各分类小组术前和术后3,6mo的裸眼视力和最佳矫正视力,观察术前和术后3mo后的散光度数。结果:对称和不对称领结形组、圆形和椭圆形组、不规则形组所占比例为76.13%,19.03%和4.84%,3组比较差异有统计学意义(P<0.05);术后3mo和6mo的裸眼视力均较术前有显著改善(P<0.05),而3mo和6mo的裸眼视力则无明显差异(P>0.05);最佳矫正视力术前、术后3组均无明显区别(P>0.05);但裸眼视力和最佳矫正视力改善情况圆形和椭圆形组最好,对称和不对称领结形组次之,最后为不规则形组。术前、术后3组的散光度数之间有显著性差异(P<0.05),术后3mo与术前差异也有统计学意义(P<0.05)。结论:Pentacam系统在近视LASIK术前角膜后表面地形图的测量分析中应用,发现不同的表面地形图和术后视力恢复情况有相关关系。     

LASEK矫治薄角膜中低度近视远期效果

目的评价准分子激光上皮下角膜磨镶术（LASEK）矫治薄角膜（中央角膜厚度〈500μm）中低度近视的远期效果和安全性。方法回顾分析LASEK矫治中低度近视术后5～7年,对比术前薄角膜者与正常角膜厚度者的屈光度、视力、对比敏感度、眩光对比敏感度、角膜内皮细胞、角膜地形图。结果薄角膜组27例52眼,正常角膜厚度组31例62眼。两组术后随访均未见圆锥角膜病例。术后矫正视力均≥1．0。裸眼视力：薄角膜组≥1．0者49眼（94．23％）,〈1．0者3眼;正常角膜组≥1．0者58眼（93．55％）,〈1．0者4眼（x^2=0．0228,P〉0．05）。角膜Haze：薄角膜组0级49眼（94．23％）,0．5级3眼;正常角膜组0级60眼（96．77％）,0．5级2眼（x^2=0．4416,P〉0．05）。角膜内皮细胞形态两组均多为六角形,形态较一致,细胞边缘整齐;平均角膜内皮细胞密度：薄角膜组（2330±294）／mm^2,正常角膜组（2413±320）／mm^2（t=1．4310,P〉0．05）;平均角膜内皮细胞面积：薄角膜（420±78）μm^2,正常角膜组（447±92）／μm^2（t=1．6875,P〉0．05）。两组术后各空间频率对比敏感度、眩光对比敏感度均差无差别（P〉0．05）。结论LASEK矫治薄角膜中低度近视安全,效果稳定,未见圆锥角膜并发症。     

LASEK、PRK和LASIK治疗中低度近视的比较

目的对比分析准分子激光上皮下角膜磨镶术(LASEK)、碰光性角膜切削术(PRK)、激光原位角膜磨镶术(LASIK)治疗中低度近视临床疗效。方法LASEK组58例(112眼)随访3-9月,PRK、LASIK组各120眼随访1a以上,观察分析术后疼痛症状,裸眼视力及角膜混浊情况。结果术后1d出现疼痛症状:LASEK组:81眼(72.3％),PRK组120 眼(100.0％),LASIK组13眼(10.8％);术后3d裸眼视力≥0.8:LASEK组24眼(21.4％),PRK组27眼(22.5％),LASIK组113 眼(94.2％);术后3月存在角膜Haze:LASEK组31眼(27.6％)、PRK组94眼(78.3％),LASIK组0眼。结论LASEK后疼痛症状、角膜Haze明显减轻,疗效优于PRK;LASEK与LASIK相比没有角膜瓣相关并发症,早期视力恢复较慢。     

准分子激光原位角膜磨镶术矫正近视散光的临床探讨

目的 探讨准分子激光原位角膜磨镶术(LASIK)矫正近视散光的临床疗效.方法 对散光等于和高于-1.50D的复性近视散光和单纯近视散光69例(115眼)施行LASIK矫正,其中循规性散光76眼,逆规性散光24眼,斜轴散光15眼.散光度-1.50D～-4.00D的106眼,-4.00D以上的9眼.结果 术后6个月达预期矫正视力者105眼(91.30%),实际矫正散光度接近术前预期矫正散光度,柱镜差值(-0.75±0.50)D者101眼.角膜地形图由术前96眼(83.48%)领结形到术后90眼(78.26%)为平滑的圆形或椭圆形.术前散光高于-4.00D的9眼中3眼未达到术前最佳矫正视力,4眼眩光、虚影不适症状持续存在.结论 LASIK矫正近视散光同治疗单纯近视一样安全有效,预测性好,但-4.00D以上的高度散光疗效欠佳.视觉质量下降.     

LASEK与LASIK治疗高度近视

目的:对比观察准分子激光上皮瓣下角膜磨削术(LASEK)与准分子激光原位角膜磨削术(LASIK)治疗高度近视的临床疗效。评估2种手术的安全性和有效性。方法:对行LASEK治疗的39例75只眼和同期行LASIK治疗的41例79只眼高度近视分别进行6个月以上的临床观察。结果:LASEK组术后1周至1个月达最佳矫正视力,术后3个月部分出现视力回退,术后6个月裸眼视力达术前矫正视力占95.83%,主要并发症有术后高眼压及Haze形成;LASIK组术后6个月裸眼视力达术前矫正视力占94.35%,主要并发症为屈光回退,角膜上皮内生或角膜瓣皱折等。结论:LASIK与LASEK均能安全、有效地矫正高度近视。     

激光角膜上皮瓣下磨镶术和激光原位角膜磨镶术治疗中高度近视的对比研究

目的比较激光角膜瓣下磨镶术(LASEK)和激光原位角膜磨镶术(LASIK)治疗中高度近视的临床效果. 方法中高度近视患者198例(394只眼).其中LASEK手术治疗93例(184只眼), LASIK手术治疗105例(210只眼). 结果术后1天,LASIK 组28 %裸眼视力达到1.0,LASEK组无1例裸眼视力达到1.0.术后1周、1、3、6月裸眼视力大于或等于1.0者,两组比较差异无显著性 (P=0.36,P=0.58,P=0.44,P=0.64).角膜地形图分析平均角膜中央屈光力与周边屈光力的差异,LASEK组(0.69)明显小于LASIK组(2.62).结论 LASEK手术矫正中高度近视均有良好的治疗效果,是一种安全、有效、预测性好的屈光手术.     

屈光手术后角膜地形图变化与临床屈光度的关系(附108眼高度近视比较分析)

为探讨准分子激光角膜内成形术和显微角膜板层切除术后角膜地形图变化与临床屈光度及视力的关系，对58例108眼高度近视术前及术后6月行角膜地形图检查并与；临床屈光度行对比分析。术后裸眼视力与术前矫正视力相等及提高者88眼（81．48％），矫正视力与术前矫正视力相等及提高者100眼（92．60％），角膜地形图示潜在视力（PVA）明显下降，角膜屈光度下降数值明显低于临床屈光度。此结果可能因角膜屈光力变化幅度超过地形图仪软件的设定分析范围而与临床实际不符。     

准分子激光角膜上皮瓣下磨镶术的临床观察

目的 观察准分子激光角膜上皮瓣下磨镶术（LASEK）治疗近视眼的临床效果。方法：选择术后随访达到6个月的146例（280眼），观察术后3天、10天，1、2、3、6个月的症状、视力、屈光状态、角膜并发症情况。结果 观察Nidek EC-5000准分子激光治疗结果表明，LASEK术后症状轻微，手术稳定性、预测性及安全性优于准分子激光屈光性角膜切削术（PRK）及准分子激光原位角膜磨镶术（LASIK）。结论 LASEK手术有可能成为今后主要的屈光治疗方法。     

高度近视LASEK 术后预留一定屈光度的疗效观察

目的:观察高度近视患者准分子激光角膜上皮瓣下角膜磨镶术(LASEK)后预留一定屈光度的临床疗效。方法:对80例高度近视患者常规行双眼LASEK手术。根据角膜厚度、屈光度将其分为两组。预留组:对40例80眼手术者预留一定屈光度(-1.00DS);普通组:40例80眼手术患者全矫。定期对两组患者术后的眼部症状、视力、屈光度、眼压、角膜厚度等进行随访观察。结果:观察发现,两组患者术后6mo视力均最佳,术后1,3a视力均稍有下降,术后3a裸眼视力基本稳定。两组术前屈光度平均在-8.25±1.23D,屈光度有平均-0.75±0.12D的回退,两组的屈光度接近。两组角膜平均曲率、角膜厚度无明显的变化,基本稳定。术后两组眼压均稳定,无继发性高眼压及青光眼等并发症发生。角膜地形图检查提示,两组术后3a无圆锥角膜症状。术后6mo;1a两组均有轻度haze出现,至术后3a均无haze发生。结论:高度近视患者LASEK术后在相对安全角膜厚度的前提下,预留一定的近视度数,为患者保留更多的基质床厚度,同样能达到预期的治疗效果,扩大了近视的矫治范围。     

LASEK联合丝裂霉素C矫正较高曲率近视

目的观察准分子激光角膜上皮瓣下磨镶术（LASEK）联合丝裂霉素C（MMC）矫正较高曲率近视的临床效果和安全性。方法应用美国雷赛公司LSX5．2准分子设备对52例（99眼）曲率较高的近视（角膜曲率大于46D）施行LASEK联合0．02％的MMC治疗。观察术后症状、裸眼视力、显然屈光度、眼压、角膜地形图及角膜上皮下雾状浑浊（haze）出现情况。结果术后5d内角膜上皮基本愈合。裸眼视力与屈光度均存术后6个月内趋于稳定。其中92眼（92．93％）等于或优于术前最佳矫正视力屈光度平均为（＋0,11±0．75）D。角膜地形图检查图形对称性良好,无明显偏心切削或不规则切削。术后有7眼（7．07％）出现haze,按照Fantes（1990）分级标准≤2级,无其他术后严重并发症。结论LASEK联合MMC矫正较高曲率近视有良好的效果。     

LASEK and photorefractive keratectomy for myopia: clinical and confocal microscopy comparison

PURPOSE: To compare postoperative visual acuity and corneal morphology after laser epithelial keratomileusis (LASEK) versus photorefractive keratectomy (PRK) in the correction of low to moderate myopia. METHODS: In a double-blind, randomized clinical trial, 50 myopic patients (mean: -4.5 +/- 1.35 diopters) were randomized to receive LASEK in one eye and PRK in the fellow eye. No mitomycin C eye drops were used in this study. Patients were observed daily for 4 days, then at 1 month and every 3 months up to 1 year. Uncorrected and best-corrected visual acuity (UCVA and BSCVA), manifest refraction, corneal epithelium healing time, postoperative pain, and corneal haze were evaluated. Corneal wound healing was quantified with corneal confocal microscopy. RESULTS: Refractive error, UCVA, and BSCVA were not statistically different between eyes treated with LASEK and PRK. Corneal epithelium healing time was 2.52 +/- 0.99 days in the eyes treated with PRK and 2.29 +/- 0.52 days in the eyes treated with LASEK (P=.22). The postoperative pain score was 2.17 +/- 0.87 in the eyes treated with PRK and 2.62 +/- 0.60 (P=.02) in the eyes treated with LASEK. Corneal confocal microscopy showed fewer stromal activated keratocytes and less extracellular matrix deposition in the eyes treated with LASEK than in the eyes treated with PRK at 1 month postoperatively (P=.003). CONCLUSIONS: LASEK is an effective and safe procedure for low to moderate myopia, but it seems more painful until full corneal reepithelization. In the early postoperative period, the corneal wound healing process is significantly less intense in eyes treated with LASEK than in eyes treated with PRK. The role of LASEK in corneal wound healing modulation remains controversial.     

Laser subepithelial keratomileusis for low to moderate myopia: 6-month follow-up

PURPOSE: To examine the effectiveness, safety, and stability of laser subepithelial keratomileusis (LASEK), a modified photorefractive keratectomy for low to moderate myopia. METHODS: This study evaluated the results of LASEK in 48 myopic patients (84 eyes) with a consecutive 6-month follow-up period. Preoperative myopia ranged from 3.25 to 7.00 diopters (D). Uncorrected and corrected visual acuity, manifest refraction, epithelial healing time, postoperative pain, subepithelial corneal haze, and complications were examined. RESULTS: Uncorrected visual acuity of 20/30 or better was achieved in 78.6% of eyes at 1 week and in 96.4% at 6 months after surgery. A mean refraction of within +/-0.50 D was measured in 42 eyes (50.0%) and +/-1.0 D in 79 eyes (94.0%) at 6 months. The epithelial healing time was 3.68 +/- 0.69 days (range, 3-6 days) and postoperative pain scores were 1.49 +/- 0.65. The subepithelial corneal haze scores were 0.56 +/- 0.34 and 0.16 +/- 0.25 at 1 and 6 months, respectively. As for complications, alcohol leakage during surgery occurred in 3 eyes, incomplete epithelial detachment in 3 eyes, contact lens intolerance in 5 eyes and steroid-induced elevated intraocular pressure (>21 mm Hg) in 1 eye. CONCLUSIONS: LASEK is an effective and safe procedure for low to moderate myopia. It can be considered an alternate type of refractive surgery for correction of low to moderate myopia.     

Factors Affecting Long-term Myopic Regression after Laser In Situ Keratomileusis and Laser-assisted Subepithelial Keratectomy for Moderate Myopia

PurposeHigh myopia is known to be a risk factor for long-term regression after laser refractive surgery. There have been few studies about the correction of moderate myopias that did not need retreatment after long-term follow-up. We evaluated 10 years of change in visual acuity and refractive power in eyes with moderate myopia after laser refractive surgery.MethodsWe included patients that had undergone laser in situ keratomileusis (LASIK) or laser-assisted subepithelial keratectomy (LASEK) to correct their myopia and that had at least 10 years of follow-up. We evaluated the stability of visual acuity in terms of safety, efficacy, and refractive changes at examinations 6 months and 1, 2, 5, 7, and 10 years after surgery.ResultsThe study evaluated 62 eyes (36 eyes in LASIK patients and 26 eyes in LASEK patients). In both groups, the efficacy index tended to decrease, and it was consistently higher in the LASEK group compared to the LASIK group over the 10 years of follow-up. The safety index improved over 10 years and was always higher than 0.9 in both groups. The difference between the spherical equivalent at 6 months postoperatively and later periods was statistically significant after 5, 7, and 10 years in both groups (LASIK, p = 0.036, p = 0.003, and p < 0.001, respectively; LASEK, p = 0.006, p = 0.002, and p = 0.001, respectively). Ten years after surgery,26 eyes (66.7%) in the LASIK group and 19 eyes (73.1%) in the LASEK group had myopia greater than 1 diopter. In comparison with the thickness at 6 months postoperatively, central corneal thickness was significantly increased after 5, 7, and 10 years in both LASIK and LASEK groups (LASIK, p < 0.001, p < 0.001, and p < 0.001, respectively; LASEK, p = 0.01, p < 0.001, and p < 0.001, respectively).ConclusionsModerately myopic eyes showed progressive myopic shifting and corneal thickening after LASIK and LASEK during 10 years of follow-up. We also found that early refractive regression may indicate the long-term refractive outcome.     

LASEK versus LASIK for the correction of moderate myopia.

PURPOSE: To compare the results of laser subepithelial keratomileusis (LASEK) and laser in situ keratomileusis (LASIK) for the correction of moderate myopia. METHODS: We performed a retrospective, single-masked, interventional study of 80 consecutive eyes. Forty eyes that had undergone LASEK to correct myopia of -2.0 to -6.0 D were compared with age and refraction matched patients treated with LASIK. All eyes had been operated by the same experienced surgeon using the same laser (Technolas 217). Mitomycin C was not used in any patient. RESULTS: Eighty eyes were reviewed (40 treated with LASEK, 40 treated with LASIK). The preoperative mean sphere was -3.8 D (range -2 to -6D) and mean cylinder was -0.7 D (range 0 to -2 D) in both groups. Postoperative uncorrected visual acuity was worse in LASEK eyes 1 and 7 days postoperatively (p = 0.0001), although the difference 7 days postoperatively ( 0.05). CONCLUSIONS: LASEK and LASIK seem to be similar in terms of safety and efficacy for the correction of moderate myopia. Nevertheless, a trend toward overcorrection was found in the LASEK group in correlation with a higher preoperative refractive error.