薄瓣LASIK术后中央角膜厚度的变化分析

目的:探讨薄瓣LASIK术后6mo内中央角膜厚度(central corneal thickness,CCT)及屈光度的变化规律.方法:使用非接触式角膜内皮细胞计追踪观察158例302眼近视眼行LASIK手术患者术前及术后1d;1wk;1,3,6mo时CCT的变化,同时记录患者的年龄,预计激光角膜切削值、术中手术光区的大小,术后预计屈光度以及实际屈光度的改变等.结果:术前平均CCT为531.6±24.3μm.术后第1d平均CCT迅速下降,术后1wk平均CCT继续下降,1mo后角膜厚度开始增厚.术前和术后第1d CCT差值与预计激光角膜切削值呈强相关性(r＝0.916,P<0.01).术后6mo和术后1d时CCT的差值,即6mo内CCT的增厚值与患者年龄、术眼屈光度和术中手术光区均呈显著负相关性(r＝ -0.180,P＝0.026;r＝-0.187,P<0.01;r＝-0.171,P＝0 137).术后6mo时,实测平均等效球镜与术前预期值接近(术前等效球镜预期值平均为0.34±0.30D).所有病例随访6mo,无1例发生屈光回退,6mo时裸眼视力均≥0.8,平均视力为1.3±0.2.结论:薄瓣LASIK术后CCT和屈光状态的稳定大约需要6mo时间.术后6mo内CCT增厚值与术前患者年龄、屈光度及术中手术光区大小均呈显著负相关性.术后6mo时实测平均等效球镜值与术前预期值接近.薄瓣LASIK手术治疗近视眼具有良好的预测性和稳定性.     

SBK治疗近视临床观察

目的:探讨准分子激光前弹力层下角膜磨镶术(subBowman’s keratomileusis,SBK)治疗近视的临床疗效。方法:回顾2009-12/2010-06间采用SBK治疗近视患者71例142眼的术前及术后6mo的视力、屈光度和角膜前后表面高度的变化。结果:术后6mo患者裸眼视力0.8~1.5,平均1.14±0.17,所有患者UCVA均≥0.8,UCVA≥1.0者136眼(95.8%),UCVA≥1.2者64眼(45.1%);术后6mo最佳矫正视力(BCVA)除2例3眼较前下降1行外,其余与术前相同或提高,BCVA均≥0.8,BCVA均≥1.0者136眼(95.8%),BCVA≥1.2者70眼(49.3%),术后6mo64眼(45.1%)UCVA≥术前BCVA。屈光度:术后6mo等效球镜(SE)为-0.65~+0.97(平均0.15±0.41)D。SE均≤±1.00D,92.8%≤±0.5D。术后6mo观察角膜前后表面高度变化大致相同。结论:SBK治疗近视有良好的预测性、准确性及安全性。     

Epi-LASIK和LASIK治疗近视散光的早期疗效对比观察

目的:探讨分析角膜微型刀上皮瓣下准分子激光原位角膜磨镶术(epipolis laser in situ keratomileusis,Epi-LASIK)和准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)治疗近视散光的疗效。方法:近视散光行Epi-LASIK治疗的患者32例64眼,LASIK治疗的患者63例126眼,将患者根据柱镜度数分为2组:Ⅰ组(柱镜-0.25～-2.75D,Epi-LASIK 20例、LASIK 48例)、Ⅱ组(柱镜-3.00～-5.00D,Epi-LASIK 12例、LASIK 15例)。随访6mo观察两种术式的疗效。对比两组患者的术后裸眼视力(uncorrected visual acuity,UCVA)、最佳矫正视力(best corrected visual acuity,BCVA)、残余散光度、角膜愈合情况、眼压及角膜地形图等。结果:术后6mo,Ⅱ组中UCVA较术前明显提高,EpiLASIK为21眼(87.5%),LASIK为19眼(63.3%),两术式相比较差异有显著性(χ2=4.055,P<0.05);残余散光度Epi-LASIK为-0.41±0.30D,LASIK为-0.74±0.36D,两术式相比较差异有显著性(t=2.672,P<0.05);角膜散光Epi-LASIK为0.63±0.34D,LASIK为0.81±0.52D,两术式相比较差异有显著性(t=2.234,P<0.05)。结论:Epi-LASIK治疗≥-3.00D散光与LASIK相比具有更好的效果和预测性。     

TOSCA治疗复杂屈光不正的临床疗效观察

目的:评价角膜地形图引导的个体化切削术治疗复杂屈光不正的临床疗效。方法:选择接受TOSCA治疗的复杂屈光不正患者共59例113眼。其中近视度数相对高角膜厚度相对薄67眼,角膜形态不规则8眼,角膜散光大33眼,PRK/LASIK术后偏心切削6眼,PRK/LASIK术后再近视5眼。术前等效球镜为平均-1.25～-13.88(平均-6.87±2.86)D。观察术后裸眼视力(uncorrected visual acuity,UCVA)、最佳矫正视力(best-corrected visual acuity,BCVA)、等效球镜、角膜曲率、角膜厚度、高阶像差及偏中心切削等。结果:UCVA术前为0.13±0.12,术后6mo为0.94±0.22,差异有统计学意义(P<0.05)。术后6mo时的平均等效球镜为(-0.45±0.48)D,在±0.5D以内。角膜曲率术前为(43.01±1.56)D,术后6mo为(37.99±1.69)D,术后与术前比较显著降低,差异有统计学意义(P<0.05)。术中平均切削厚度为(88.30±28.86)μm,比按照其相同屈光度和切削直径的传统LASIK/LASEK手术的切削厚度(117.93±32.72)μm节约了约(27.77±23.24)μm,差异无统计学意义(P>0.05)。术前总高阶像差、水平彗差、垂直彗差及球差值分别为0.50±0.23,0.10±0.08,0.14±0.12,0.12±0.09,术后6mo时分别为0.68±0.25,0.21±0.22,0.32±0.18,0.38±0.14,差异有统计学意义(P<0.05)。术前6例因PRK和LASIK术后造成的偏中心切削,其偏中心切削距离均>1.0(平均1.33±0.45)mm,术后偏中心切削平均为(0.49±0.22)mm,差异有统计学意义(P<0.05)。结论:TOSCA治疗复杂屈光不正术后有较好的安全性、有效性和预测性,且可以在一定程度上节约角膜厚度。     

玻璃体切除手术后对人工晶状体度数计算的影响

目的:评估玻璃体切除手术对人工晶状体计算的影响。方法:通过测量玻璃体切除手术术前、术后角膜曲率、眼轴长等指标测算预装晶状体残留屈光度,并与术后3mo验光实测等值球镜屈光度的偏差比较验证。结果:患者玻璃体切除手术术前后角膜曲率、眼轴长无明显差异。玻璃体切除手术术前、术后预测残留屈光度和术后3mo验光实测残留屈光度分别为-0.21±0.09D,-0.36±0.08D和-0.42±0.14D,P>0.05,差异不显著。结论:玻璃体切除手术不影响对人工晶状体精确测定。     

预留不同屈光度对LASIK手术患者的影响

目的:评价术前预留不同屈光度对LASIK手术患者的影响。方法:对486眼近视LASIK手术患者进行回顾性分析。按预留屈光度不同分成3组:Ⅰ组(全矫组)219眼,Ⅱ组(预留-0.25D组)215眼,Ⅲ组(预留-0.50D组)52眼。观察术前、手术后1,3和6mo裸眼远视力和等值球镜屈光度。结果:术后裸眼视力:各组术后各时间段与术前矫正视力间无显著差异。术后等值球镜屈光度:各组1mo与3mo,1mo与6mo比较有显著差异(P<0.05)。术后3,6moⅢ组和Ⅰ组、Ⅱ组间比较有显著差异(P<0.05)。结论:术前预留-0.25D以内屈光度6mo内对近视LASIK手术患者裸眼远视力和屈光无明显影响,术前预留-0.50D术后3mo开始影响患者术后屈光,达到预防老视的目的。     

ICL植入术矫正超高度近视的临床效果观察

目的:评估有晶状体眼后房型人工晶状体(ICL)矫正超高度近视的疗效及安全性。方法:对超高度近视患者20例40眼接受普通型ICL或散光型后房型人工晶状体(TICL)治疗,术前屈光度球镜-10.0～-18.0D,柱镜-0.25～-3.00D,等效球镜-15.32D,术后随访12mo,观察指标包括UCVA,BCVA、角膜地形图、主观和客观验光、角膜内皮细胞计数、眼压测量、裂隙灯检查。结果:术后12mo,裸眼视力≥0.8者占80.0%(32眼)。30.0%(12眼)的术眼BCVA较术前提高1行,15.0%(6眼)的术眼BCVA较术前提高2行。术后12mo术眼屈光度在±0.50D者达70.0%(28眼)。术前患者平均眼压为16±2.8mmHg,术后6mo平均眼压为17±3.4mmHg,术前术后相比较差异无显著性(t=0.518,P=0.776),术前患者角膜内皮细胞计数平均为2823±243.6个/mm2,术后6mo平均为2709±273.2个/mm2,术前术后比较无显著性差异(t=0.794,P=0.422)。未发生继发性青光眼、视网膜脱离及并发性白内障。结论:ICL植入术矫正超高度近视具有良好的疗效和安全性,远期效果有待进一步观察。     

LASIK治疗RK后屈光欠矫临床观察

目的评价准分子激光原位角膜磨削术(LASIK)治疗放射状角膜切开术(RK)术后屈光欠矫的临床效果。方法对34眼(21人)RK术后残余近视、散光患者行LASIK治疗,年龄20～38岁,残余球镜屈光度-2.00～-13.00D(-5.87D±2.65D),柱镜屈光度0～3.5D(-1.15D±0.94D)。结果术后6个月屈光稳定,裸眼视力≥术前矫正视力32眼(94.12％),所有眼屈光度在术前预期矫正±1.00D以内。1眼最佳矫正视力较术前下降l行。无角膜瓣移位、脱失、角膜混浊等并发症。结论LASIK治疗RK后屈光欠矫安全、有效、预测性好。     

微型角膜刀准分子激光角膜上皮瓣下磨镶术矫治薄角膜近视的疗效观察

目的:探讨微型角膜刀准分子激光角膜上皮瓣下磨镶术(Epi-LASIK)矫治薄角膜近视的疗效、安全性、稳定性.方法:对10例(20眼)无法行准分子激光原位角膜磨镶术(LASIK)的相对薄角膜近视患者行Epi-LASIK手术.术前近视球镜为-4.00～-10.25 D,平均(-7.32±1.66)D,柱镜0～-2.50 D,平均(-0.71±0.72)D.术前角膜厚度463～519 μm,平均(491±20)μm.观察术中术后并发症,并对术后1～6 mo裸眼视力、屈光度及上皮下雾状浑浊(Haze)进行随访.结果:术中无严重并发症,术后最佳矫正视力与术前相比无1例下降,术后6mo球镜平均(-0.04±0.18)D,柱镜平均(-0.20±0.44)D.20眼等效球镜均在-0.75～ 0.75D之间,其中17眼(85%)等效球镜在-0.50～ 0.50D之间.角膜厚度平均(412±14)μm.Ⅰ级Haze者为1眼.结论:Epi-LASIK对于薄角膜近视治疗安全有效,可作为薄角膜中高度近视的首选术式.     

两种准分子激光机临床应用的对比研究

目的:通过对VisxStarS4和AllegrettoWavelight激光仪LASIK术后视力、屈光度及角膜厚度的比较,探讨两台激光仪的优缺点。方法:选择等效球镜屈光度≤6.00D的近视和近视散光患者,VisxStarS4为第I组,AllegrettoWavelight为第II组,术前的视力、屈光度和角膜厚度进行比较,术后3mo再对这三项进行比较,同时对两台机器切削深度的精确性进行比较,以期得出较肯定的结论。结果:术前第Ⅰ组的矫正视力(对数视力)为0.71±0.004,第Ⅱ组的为0.71±0.0042;术前I组的屈光度为-4.57±1.20D,术前Ⅱ组的为-4.59±1.15D;术前第Ⅰ组的角膜厚度为538.87±29.99μm,术前第Ⅱ组的为543.48±31.53μm。3组数据间均有可比性。术后第Ⅰ组的裸眼视力(对数视力)为0.707±0.07,第Ⅱ组的为0.71±0.05;术后第Ⅰ组的屈光度为-0.02±0.29D,术后第Ⅱ组的屈光度为0.01±0.22D;术后第Ⅰ组的角膜厚度为481.07±33.11μm,术后第Ⅱ组的为471.77±40.28μm。3组数据中只有视力两组间差异有统计学意义。机器设置的切削深度第Ⅰ组为67.71±16.55μm,实际切削57.61±17.20μm;而第Ⅱ组机器设置的切削深度75.29±17.70μm,实际切削71.60±24.60μm,经统计学分析(PⅠ=0.000,PⅡ=0.250)。结论:VisxStarS4在屈光度矫正方面的预测性较好,并可以保留更多的角膜组织,但术后视力欠理想,角膜切削深度的预测性较差;而AllegrettoWavelight无论是屈光度的矫正还是角膜的切削深度都有良好的预测性,术后视力较好,只是切削的角膜组织比较多,不适合高度近视或角膜薄患者的治疗。     

Wavefront-guided laser in situ keratomileusis with the Bausch & Lomb Zyoptix system

PURPOSE: To evaluate the clinical results of wavefront-guided laser in situ keratomileusis (LASIK) with the Zyoptix system. METHODS: Twelve patients (24 eyes) underwent wavefront-guided LASIK with the Bausch & Lomb Zyoptix system. Uncorrected and best spectacle-corrected visual acuity and manifest refraction were measured at postoperative day 1, week 1, and months 1 and 3. A subjective vision quality questionnaire evaluated light sensitivity, dryness, tearing, glare, halos, ghost images, and difficulties in night driving, preoperatively and 3 months postoperatively. RESULTS: Preoperatively, mean sphere was -3.70 +/- 2.33 D (range -0.50 to -8.00 D), mean cylinder was -0.90 +/- 0.98 D (range 0 to -3.00 D), and mean spherical equivalent refraction was -4.15 +/- 2.16 D (range -1.38 to -8.25 D). Three-month postoperative spherical equivalent refraction was within +/- 0.50 D of emmetropia in 17 eyes (70.8%) and within +/- 1.00 D in 22 eyes (91.7%). At 3 months postoperatively, no eyes lost any lines of BSCVA and eight eyes (33.3%) gained 2 lines. The ratio of postoperative BSCVA to preoperative BSCVA (safety) was 1.05 +/- 0.09 (range 1.00 to 1.20) at 1 month and 1.07 +/- 0.10 (range 1.00 to 1.29) at 3 months. The ratio of postoperative UCVA to preoperative BSCVA (efficacy) was 0.96 +/- 0.12 (range 0.80 to 1.20) at 1 month and 0.95 +/- 0.12 (range 0.8 to 1.2) at 3 months. The subjective vision quality questionnaire revealed less tearing, fewer halos, and less difficulty in night driving after wavefront-guided LASIK. Comparison of higher order optical aberrations before and after surgery was not done. CONCLUSIONS: Wavefront-guided LASIK with the Bausch & Lomb Zyoptix system was safe and effective in correcting low to moderate myopic refractive error.     

Posterior corneal ectasia following LASIK

PURPOSE: To evaluate the cases of posterior corneal ectasia following laser in situ keratomileusis. MATERIAL AND METHODS: Thirteen eyes of 7 patients, that were diagnosed to have posterior corneal ectasia (?0.060 mm) on Orbscan topographic system following LASIK, were identified. The parameters evaluated were uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), refraction, contrast sensitivity, glare, corneal topography, keratometry and pachymetry. The preoperative and postoperative data at day 1, 1 week, 1 month, 3 months, 6 months and 1 year were retrospectively analyzed. RESULTS: The mean UCVA of the patients before LASIK surgery was 0.032 +/- 0.04. It was 0.320 +/- 0.159 in follow-up of LASIK surgery after 1 year. The mean Pre-LASIK BCVA was 0.59 +/- 0.11. There was no change in mean BCVA at 1 year. The mean preoperative spherical equivalent was -14.25 +/- 2.91 D except in 2 hyperopic eyes in which the mean spherical equivalent preoperatively was +5.75 +/- 0.35 D. The mean postoperative spherical equivalent after 1 year of LASIK surgery in last follow-up (+/- enhancement) was - 3.45 +/- 2.08 in the myopic eyes and + 1.0 +/- 0.70 in the two hyperopic eyes. The mean preoperative posterior corneal elevation was 0.022 +/- 0.011 mm, which at the end of 1 week following LASIK was 0.067 +/- 0.009 and at 1 year/ last follow-up following LASIK, it was 0.068 +/- 0.006 mm. CONCLUSIONS: Higher amplitudes of refractive correction may lead to the occurrence of posterior corneal ectasia.     

Corneal wavefront-guided ablation with the Schwind ESIRIS laser for myopia

PURPOSE: To evaluate the outcome of corneal wavefront-guided LASIK for the treatment of myopia and myopic astigmatism. METHODS: This study included 56 myopic virgin eyes of 28 patients with a mean spherical equivalent refraction of -4.40 +/- 1.83 diopters (D) (range: -1.25 to -9.75 D) and astigmatism < 2.50 D. The corneal wavefront aberrations were analyzed using a corneal topography system. The preoperative corneal wavefront aberration data obtained from the above analyses combined with manifest refraction were used to generate a customized ablation profile. The safety, efficacy, and predictability of the correction, contrast sensitivity, and corneal higher order wavefront aberrations were evaluated. RESULTS: At 1-year follow-up, the mean residual spherical equivalent refractive error was -0.15 +/- 0.3 D (range: 0 to -1.25 D) and mean cylinder was -0.54 +/- 0.34 D (range: 0 to -1.50 D). Ninety-five percent of eyes were in the residual refractive error range of +/- 0.50 D and uncorrected visual acuity improved by 1.00 D or better in 94% of eyes. The safety index and efficacy index were 1.13 and 0.92, respectively. After treatment, corneal higher order wavefront aberrations with a 6-mm pupil diameter increased significantly (paired sample t test, P < .01), and contrast sensitivity with glare had small reductions at high spatial frequencies. Changes in spherical-like aberration (R = 0.708, P < .001) and higher order wavefront aberration (R = 0.449, P = .001), except for coma-like aberration (P = .238), were positively correlated with the amount of achieved correction. CONCLUSIONS: Evaluation of clinical results showed that corneal wavefront-guided LASIK for the correction of myopia and myopic astigmatism was safe and effective. There was an increase in all higher order aberrations postoperatively.     

Comparison of higher-order aberrations after wavefront-guided laser in situ keratomileusis and laser-assisted subepithelial keratectomy

PURPOSE: To compare the higher-order aberrations (HOAs) in 70 eyes (38 patients) that had wavefront-guided laser in situ keratomileusis (LASIK) with those in 70 eyes (40 patients) that had wavefront-guided laser-assisted subepithelial keratectomy (LASEK) for the treatment of myopia. SETTING: Department of Ophthalmology, Yonsei University College of Medicine, Myongdong Bal-geun sesang Eye Clinic, and Seran Eye Center, Seoul, Korea. METHODS: In a prospective study, 140 consecutive eyes of 78 patients were treated with wavefront-guided LASIK or LASEK according to the patient's choice after each procedure had been thoroughly explained. The patients were followed for 6 months. Best corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), manifest refraction, and wavefront aberrations were measured at baseline and 1, 3, and 6 months after surgery. RESULTS: There were no significant differences in postoperative BCVA, UCVA, and manifest refraction between groups. The mean root-mean-square wavefront error of HOAs for a scotopic pupil in the wavefront-guided LASIK group was significantly smaller than that in the wavefront-guided LASEK group at 1 month. Analyzing individual Zernike coefficients, the spherical aberration and second coma were significantly smaller in the wavefront-guided LASIK group than in the wavefront-guided LASEK group at 1 month. This difference in HOAs between groups disappeared at 3 and 6 months. CONCLUSIONS: The HOAs in the scotopic condition were not different between the wavefront-guided LASIK and LASEK groups beginning 3 months after surgery. However, the HOAs in the LASIK and LASEK groups had a different time course, especially in the case of spherical aberration. This finding suggests that postoperative changes in aberration contribute to the final outcome of wavefront-guided ablation.     

Corneal wavefront-guided enhancement for high levels of corneal coma aberration after laser in situ keratomileusis

PURPOSE: To evaluate the improvement in visual and optical performance after corneal wavefront-guided laser in situ keratomileusis (LASIK) enhancement in patients with high levels of corneal coma aberration and complaints about quality of vision. SETTING: Vissum-Instituto Oftalmológico de Alicante, Alicante, Spain. METHODS: Corneal wavefront-guided LASIK enhancement was performed in 34 symptomatic eyes of 29 patients aged 26 to 64 years with previous LASIK surgery and a significant level of primary coma aberration. The ablation design was calculated using ORK-CAM software (Schwind eye-tech-solutions). The follow-up period was 6 months. Changes in refraction, corneal aberrometry, and subjective symptoms were analyzed. RESULTS: At 6 months, the mean efficacy index was 0.88 +/- 0.12 and the mean safety index, 1.03 +/- 0.16. The reduction in sphere and cylinder at 1 month was statistically significant (P<.01). Of all eyes, 97.06% had a spherical equivalent within +/-1.00 diopter. At 1 month, statistically significant changes were observed: total (P = .01), and primary coma root mean square reduction (P<.01), and negativization of the primary spherical aberration coefficient (P<.01). At 6 months, patient perception of halos and glare was reduced or eliminated in a high percentage of cases. CONCLUSION: Corneal wavefront-guided enhancements with the ORK-CAM system are a useful tool for the correction of the second order refractive errors and for the reduction of the corneal primary coma induced by previous keratorefractive procedures.     

Safety,efficacy, predictability and stability of laser in situ keratomileusis (LASIK) with a 1000‐Hz scanning spot excimer laser

Purpose: To evaluate the safety, efficacy, predictability and stability of laser in situ keratomileusis (LASIK) with a 1000‐Hz scanning spot excimer laser (Concept System 1000; WaveLight GmbH, Erlangen, Germany). Methods: LASIK was performed on twenty eyes with myopia or myopic astigmatism (mean spherical equivalent refraction: ?3.97 ± 1.72 dioptres (D); mean cylinder: ?0.84 ± 0.77 D) using a microkeratome for flap creation and the Concept System 1000 for photoablation. Patients were examined preoperatively as well as 1, 3 and 6 months after the treatment. Manifest sphere and cylinder, uncorrected (UCDVA) and best corrected (BCDVA) distance visual acuity, corneal topography and pachymetry were analysed. Results: We observed no adverse events that might have been associated with the use of a repetition rate of 1000 Hz. All eyes maintained or had improved BCDVA at 6 months after treatment when compared to preoperative values. Six months after LASIK, UCDVA was 20/20 or better in 85% and 20/25 or better in 100% of the eyes. The spherical equivalent refraction was within ±0.50 D in 95% of the eyes at 6 months after surgery. The refraction stayed stable over time; 95% of the eyes changed <0.5 D postoperatively. Conclusion: LASIK with the prototype 1000‐Hz excimer laser was safe, efficient and predictable. The postoperative refraction was stable over time. There were no specific clinical side‐effects that might be associated with the use of such a high repetition rate.     

飞秒激光制瓣LASIK及TransPRK手术治疗近视对角膜像差的影响

目的 观察飞秒激光制瓣LASIK手术及TransPRK手术治疗低中度近视患者对角膜像差的影响。设计 前瞻性病例对照研究。研究对象 等效球镜度-1.00 ~ -6.75 D的近视患者73例131眼。方法 37例68眼行飞秒激光制瓣LASIK手术,36例63眼行TransPRK手术。均使用阿玛仕准分子激光消像差切削模式。术前及术后1、3、6个月进行视力、屈光度、波前像差仪检查。主要指标 视力、残余屈光度、彗差、球差、总高阶像差。结果 术后1个月,飞秒激光制瓣LASIK组裸眼视力达到或超过术前最佳矫正视力者为75%,TransPRK组为47.62%（P=0.001）。术后3个月及6个月,飞秒激光制瓣LASIK组裸眼视力达到或超过术前最佳矫正视力者分别为86.76%、91.18%,TransPRK组分别为79.37%、90.48% （P=0.26,0.89）。术后残余屈光度,在术后3个月TransPRK组（0.13±0.35 D）较飞秒激光制瓣LASIK组（-0.02±0.41 D）略高,术后1个月及6个月均无显著差别。两组术后高阶像差均较术前提高（P<0.001）。术后1个月角膜彗差在TransPRK组为（0.25±0.10 μm）,较飞秒激光制瓣LASIK组（0.30±0.17 μm）小（P=0.04）;术后3、6个月角膜彗差在TransPRK组分别为（0.28±0.10 μm）、（0.30±0.12 μm）,与飞秒激光制瓣LASIK组（0.31±0.16 μm）、（0.35±0.11 μm）相似（P=0.12,0.13）。术后各时间点两组的球差、总高阶像差差异均无统计学意义。结论 飞秒激光制瓣LASIK手术及TransPRK手术治疗低中度近视患者术后角膜像差均有所提高,术后1个月TransPRK角膜彗差较飞秒激光制瓣LASIK小,术后3个月及6个月两种手术方式对角膜像差的影响相似。（眼科,2015,24：225-229）     

Nomogram considerations with the Technolas 217A for treatment of myopia

PURPOSE: To determine whether surgeon-specific nomogram adjustments are useful when using the Technolas 217A excimer laser for treating myopia and myopic astigmatism. METHODS: We conducted a prospective evaluation of 216 consecutive eyes with 6 months follow-up after treatment of myopia or myopic astigmatism with the Technolas 217A laser. Attempted vs. achieved change in refraction was analyzed with a statistical analysis software program. Factors such as age, corneal thickness (pachymetry), preoperative spherical equivalent refraction, preoperative cylinder, and optical zone were studied to evaluate their role in predicting refractive outcome at 6 months after LASIK. RESULTS: The mean value of attempted spherical equivalent refraction was -5.32 +/- 2.72 D. The mean achieved refractive correction at 6 months was -5.55 +/- 2.78 D, with a mean spherical equivalent of 0.13 +/- 0.54 D. The percent achieved effect at 1 month was 105%, and at 6 months, 103%. Preoperative spherical equivalent refraction and optical zone size were strong predictors of 6-month LASIK outcome. There was a 9% difference in the percent achieved effect between a 4 and 7-mm optical zone. There was no correlation between age, preoperative cylinder, or surgeon and 6-month outcome. CONCLUSIONS: Surgeons using the planoscan software on the Technolas 217A may experience a small initial overcorrection. There may be a benefit to reducing the treatment given with larger optical zones and smaller corrections.     

Photorefractive keratectomy after cataract surgery in uncommon cases: long-term results

AIM: To evaluate the efficacy and safety of the excimer laser correction of the residual refractive errors after cataract extraction with intraocular lens (IOL) implantation in uncommon cases. METHODS: Totally 24 patients with high residual refractive error after cataract surgery with IOL implantation were examined. Twenty-two patients had a history of phacoemulsification and IOL implantation, and two had extra-capsular cataract extraction with IOL implantation. Detailed examination of preoperative medical records was done to explain the origin of the post-cataract refractive errors. All patients underwent photorefractire keratectomy (PRK) enhancement. The mean outcome measures were refraction, uncorretted visual acuity (UCVA), best corrected visual acuity (BCVA) and corneal transparency and follow up ranged from 1 to 8y. RESULTS: The principal causes of residual ametropia was inexact IOL calculation in abnormal eyes with high myopia and congenital lens abnormalities, followed by corneal astigmatism both suture induced and preexisting. After cataract surgery and before the laser enhancement the mean spherical equivalent (SE) was -0.56±3 D ranging from -4.62 to +2.25 D in high myopic patients, instead it was -1±1.73 D ranging from -3.25 to +3.75 D in the astigmatic eyes, with a mean cylinder of -3.75±0 ranging from -3 to +5.50 D. After laser refractive surgery the mean SE was 0.1±0.73, ranging from -0.50 to +1.50 in the myopic group, and it was -0.50±0.57 ranging from -1.25 to +0.50 in astigmatic patients, with a mean cylinder of -0.25±0.75. In myopic patients the mean UCVA and BCVA were 0.038±0.072 logMAR and 0.018±0.04 respectively, both ranging from 0.10 to 0.0. In astigmatic patients, the mean UCVA and BCVA were 0.213±0.132 and 0.00±0.0 respectively, UCVA ranging from 0.50 to 0.22 and BCVA was 0.00. All patients presented normal corneal transparency. No ocular hypertension was detected and no corneal haze was observed. All registered values remained stable also at the end line evaluation. CONCLUSION: The excimer laser treatment of residual refractive errors after cataract surgery with IOL implantation in abnormal eyes resulted in satisfactory and stable visual outcome with good safety and efficacy.     

Wavefront-guided laser in situ keratomileusis with the Alcon CustomCornea and the VISX CustomVue: three-month results

PURPOSE: To evaluate and compare the visual and clinical outcomes of wavefront-guided laser in situ keratomileusis (LASIK) with the Alcon CustomCornea (Alcon Laboratories Inc, Fort Worth, Tex) and VISX CustomVue (VISX, Santa Clara, Calif) systems. METHODS: Ninety-three eyes of 56 patients (50 and 43 consecutive eyes on CustomCornea and CustomVue, respectively) were enrolled in a prospective multisurgeon clinical outcome study. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and manifest refraction were measured at 1 day, 1 week, 1 month, and 3 months postoperatively. Early treatment diabetic retinopathy study (ETDRS) visual acuity and contrast sensitivity were measured at 1 month and 3 months, and wavefront mapping at 3 months. RESULTS: Preoperatively, the CustomCornea group had a mean sphere of -3.90 +/- 1.62 diopters (D) (range -0.50 to -7.25 D), mean cylinder of +0.62 +/- 0.39 D (range 0 to +1.50 D), and mean manifest spherical equivalent refraction of -3.59 +/- 1.54 D. The CustomVue group had a sphere of -3.87 +/- 1.45 D (range -1.75 to -6.75 D), cylinder of +0.49 +/- 0.36 D (range 0 to +1.50 D), and manifest spherical equivalent refraction of -3.62 +/- 1.46 D. At 3 months, 98% of the CustomCornea group and 95% of the CustomVue group were within +/-0.50 D. Ninety-nine percent of eyes did not change >0.50 D (manifest spherical equivalent refraction) between 1 month and 3 months. CustomCornea eyes improved on contrast sensitivity testing and had a better profile than CustomVue for 20/15 Snellen and 20/12.5 ETDRS acuity. Both laser groups had a decrease in higher order aberrations with statistical significance for coma and spherical aberration in the CustomCornea group. CONCLUSION: Wavefront-guided LASIK with both systems is safe and effective.