Laser subepithelial keratomileusis for the correction of high myopia with the Schwind ESIRIS scanning spot laser

PURPOSE: To investigate the efficacy of laser subepithelial keratomileusis (LASEK) for the correction of high myopia with the Schwind ESIRIS scanning spot laser (Schwind eye-tech-solutions Gmbh & Co, Kleinostheim, Germany). METHODS: Fifty-one patients (76 eyes) were treated with a mean preoperative spherical equivalent refraction of -7.55 diopters (D) (range: -6.0 to -10.75 D). All eyes received a LASEK technique using 15% alcohol with a 20-second application. RESULTS: An intact epithelial flap was obtained in 73 (96%) eyes. At 1 week, uncorrected visual acuity (UCVA) was > or =20/30 in 53 (70%) eyes and > or =20/60 in all eyes. At 6 months (n=76), the mean SE was +0.08 D (range: -1.00 to +1.875 D) with 73 (96%) eyes within +/-1.0 D of the intended correction and 60 (79%) eyes within +/-0.5 D. At 12 months (n=46), the mean SE was -0.07 D (range: -1.375 to +2.0 D) with 44 (96%) eyes within +/-1.0 D of the intended correction and 37 (80%) eyes within +/-0.5 D. Myopic cylindrical corrections were attempted in 68 eyes (range: -0.25 to -4.25 D) with vector analysis demonstrating a mean 85% correction. At last follow-up, UCVA was > or =20/20 in 47 (62%) eyes, > or =20/25 in 63 (83%) eyes, and > or =20/40 in 75 (99%) eyes. Three (4%) eyes gained two lines of Snellen decimal equivalent best spectacle-corrected visual acuity compared to preoperative levels, 68 (89%) eyes showed no change or gained one line, and 5 (7%) eyes lost one line. None lost more than one line. Only 2 (3%) eyes at 6 to 12 months had more than +1 axial corneal haze and 50 (66%) showed no evidence of haze on slit-lamp examination. CONCLUSIONS: Laser subepithelial keratomileusis for myopia up to -11.00 D with the Schwind ESIRIS laser provides good refractive and visual outcomes, with acceptable visual recovery and minimal complications.     

Laser epithelial keratomileusis for the correction of hyperopia using a 7.0-mm optical zone with the Schwind ESIRIS laser

PURPOSE: To investigate the efficacy of laser epithelial keratomileusis (LASEK) for the correction of hyperopia using a 7.0-mm optical zone and a 9.0-mm total ablation zone diameter with the Schwind ESIRIS flying-spot laser. METHODS: Forty-seven patients (70 eyes) were treated with a mean preoperative spherical equivalent refraction of +2.32 diopters (D) (range: 0 to +5.00 D). All eyes underwent LASEK using 15% alcohol with a 20-second application. RESULTS: An intact epithelial flap was obtained in 66 (94%) eyes. In 70 eyes at 12 months, the mean spherical equivalent refraction was +0.09 D (range: -0.75 to +1.00 D) with all (100%) eyes within +/- 1.00 D of the intended correction and 60 (86%) eyes within +/- 0.50 D. In 40 eyes with 24-month follow-up, the refractive correction remained stable after 6 months. Hyperopic cylindrical corrections were attempted in 49 eyes (range: +0.25 to +5.00 D) with vector analysis demonstrating a mean 102% correction at 12 to 24 months. In 60 non-amblyopic eyes, uncorrected visual acuity was > or = 20/20 in 47 (78%) eyes. Thirty-three (47%) eyes gained 1 to 2 lines of Snellen decimal equivalent best spectacle-corrected visual acuity, 30 (43%) eyes showed no change, and 7 (10%) eyes lost 1 line. Eight (11%) eyes at 12 to 24 months had grade +/- 1 of paracentral corneal haze and 57 (81%) had no haze. At 12 months (n = 70), the safety index was 1.06 with an efficacy index of 0.95. Analysis of higher order wavefront aberrations showed no significant changes in root-mean-square values post-operatively, except for a significant reduction of fourth order spherical aberration (P < .05). CONCLUSIONS: Laser epithelial keratomileusis for hyperopia up to +5.00 D using a 7.0-mm optical zone with the Schwind ESIRIS laser provides excellent refractive and visual outcomes with minimal complications. In eyes followed for 24 months, the refractive correction remained stable after 6 months.     

WG-LASIK与WG-LASEK治疗中低度近视的临床疗效比较

目的:比较波前像差引导的准分子激光原位磨镶术(wave-front-guided LASIK,WG-LASIK)与波前像差引导的准分子激光上皮瓣下磨镶术(wavefront-guided LASEK,WG-LASEK)治疗中低度近视的疗效。方法:80例患者(160眼)随机分为WG-LASIK组和WG-LASEK组,每组40例(80眼)。术后随访观察上皮愈合时间与疼痛情况,术后2wk;1,2,3,6mo;1a时术后裸眼视力、屈光度数、角膜上皮下雾状混浊(Haze)和高阶像差。术后3,6mo时做视觉质量问卷调查。结果:两组术后眼痛程度,上皮愈合时间,屈光度数及角膜Haze无显著性差异。两组裸眼视力、暗视瞳孔下高阶像差的均方根值有显著性差异,且时间曲线不相同。结论:WG-LASIK与WG-LASEK矫正中低度近视均能取得较好的临床效果,用来矫正中低度近视是安全,有效的。术后裸眼视力、视觉成像质量及视力稳定程度方面,WG-LASEK更优于WG-LASIK。     

Comparison of optical quality parameters and ocular aberrations after wavefront-guided laser in-situ keratomileusis versus wavefront-guided laser epithelial keratomileusis for myopia

Background

To compare optical quality, ocular scattering, and higher-order aberrations (HOAs) after laser in-situ keratomileusis (LASIK) versus laser epithelial keratomileusis (LASEK).

Methods

A total of 47 eyes from 47 participants who had undergone LASIK (group I) or LASEK (group II) procedure at least 6 months prior were enrolled. Ocular aberrations and modulation transfer function (MTF) values measured using iTrace, a ray-tracing type aberrometer, were compared to MTF (modulation transfer function) cut-off values, Strehl ratio, and objective indices of scattering obtained using the Objective Quality Analysis System II (OQAS II).

Results

There was no significant correlation between the postoperative optical quality parameters and the HOAs between both groups. In group I, the MTF cut-off value was significantly correlated with cylinder refraction (p?=?0.037), and the objective scattering index (OSI) was positively correlated with spherical equivalent (p?=?0.023). In group II, there was a statistically significant correlation between the OSI and achieved refractive correction (p?=?0.001). Regression analysis showed that the OSI was the most significant predictor of MTF cut-off values after refractive surgery. Additionally, MTF values measured by OQAS were significantly lower than those measured by iTrace without correlation.

Conclusion

Optical quality after refractive surgery may be influenced by not only ocular aberrations but also by scattering. Even though the accuracies of the machines used in this study to measure optical quality have yet to be proven, this study showed limited correlation among the values measured using the two different machines after refractive surgery. Therefore, for more generalized evaluation of visual function after refractive surgery, more advanced optical devices still need to be developed.     

波前像差引导个体化切削治疗高度近视

目的 观察波前像差引导的个体化切削治疗高度近视患者手术前后视力、对比敏感度、眩光以及波前像差的变化,评价其对视觉质量的影响.方法 回顾性病例研究.对2007年10月至2008年10月在武警河南总队医院眼科就诊,选取屈光度为-6.0≤球镜≤-10.0D,柱镜≤-2.0D的高度近视患者200例(380只眼)行波前像差引导的个体化切削,手术治疗区直径均＞6.0mm.检查术前及术后1周、1月、3月及6月患者的裸眼视力、屈光度、对比敏感度和波前像差.统计分析使用SPSS11.0软件包的独立样本进行t检验.结果 波前像差引导的个体化切削患者术后裸眼视力均达到术前矫正视力,部分患者比术前矫正视力提高2行;术后1周高阶像差增加,术后1月和3月逐渐降低,术后3月和术前比较差异仍有统计学意义(P＜0.05);术后1周各空间频率的对比敏感度及眩光敏感度与术前比较均明显下降,差异有统计学意义(P＜0.05),术后3月时各空间频率对比敏感度和眩光敏感度均有恢复,低频率段恢复至接近术前水平,中、高频率段恢复较慢.和术前比较差异仍有统计学意义(P＜0.05).结论 波前像差引导的个体化切削有效地提高高度近视患者的远视力,部分患者可以获得超常视力,但是术后仍有高阶像差的增加和对比敏感度的下降.

Abstract：

Objective To observe the pre and postoperative changes of visual quality, contrast sensitivity (CS), glare contrast sensitivity (GCS) and wavefront aberration in high myopic patients who received wave-front guided customized ablation (WAGCA). Methods It was a retrospective case series. High myopic patients were collected in Henan peoples armed police corps hospital from October,2007 to October, 2008. A total of 380 eyes in 200 high myopic patients with preoperative spherical refraction of -6.0 D to -10.0 D and astigmatism ＜2 D received WAGCA. The ablation zone was ＞6.0mm. The uncorrected visual acuity (UCVA), CS, GCS and corneal wave-front aberrations were analyzed before surgery and at 1 week, 1 month and 3 months postoperatively. Results After WAGCA,uncorrected visual acuity (UCVA) in all of the patients recovered to or better than the preoperative best spectacled-corrected visual acuity (BSCVA). High order aberrations (HOA) increased at 1 week and then decreased slowly at 1 month and 3 months postoperatively. But the statistical difference was still significant at 3 months (P＜0.05). The postoperative CS and GCS of every space frequency decreased after WAGCA. The difference between the preoperative and 1 week after operation was significant (P ＜0.05). At 3 months postoperatively, the low space frequency recovered nearly to preoperative level, but the difference of the medium and high space frequency was still statistically significant (P ＜0.05). Conclusions WAGCA is effective on correcting high myopia and some patients can gain super visual acuity, but the HOA increases and the CS and GCS decrease after WAGCA. The wave-front aberration, CS and GCS measurements combined with usual examination can more effec tively evaluate the changes of visual function after WAGCA.     

Corneal wavefront-guided retreatments for significant night vision symptoms after myopic laser refractive surgery

PURPOSE: To evaluate the results of corneal wavefront (WF)-guided enhancements in patients with night vision symptoms and significantly high positive spherical aberration (SA) after myopic laser refractive surgery. DESIGN: Noncomparative, interventional case series. METHODS: Twenty-eight eyes of 20 patients with significant night vision symptoms and positive corneal SA (Z(4)(0)) higher than 0.5 microm after myopic laser refractive surgery were included in the study at Vissum-Instituto Oftalmologico de Alicante, Spain. Enhancement surgery was planned to remove residual refractive error and corneal SA (Z(4)(0)) in all cases. All patients underwent corneal WF-guided excimer laser retreatments using the ESIRIS/SCHWIND excimer laser system (Schwind Eye Tech Solutions, Kleinostham, Germany). The main outcome measures were visual symptoms, change in corneal SA (Z(4)(0)), and corneal asphericity (Q-value). RESULTS: Subjective reports of night vision symptoms were improved in all patients. Mean corneal SA (Z(4)(0)) decreased from 0.75 +/- 0.19 microm before surgery to 0.43 +/- 0.42 microm after surgery (P < .001). Mean asphericity in the 4.5-mm zone significantly decreased from 1.02 +/- 1.07 before surgery to 0.52 +/- 0.88 after surgery (P = .008), and the mean asphericity in 8 mm did not change significantly (P = .362). The mean spherical equivalent significantly shifted to hyperopia from -0.22 +/- 1.14 diopters (D) before surgery to 0.33 +/- 0.54 D after surgery (P = .025). CONCLUSIONS: Cornea wavefront-guided retreatment was effective in improving subjective night vision symptoms, reducing corneal SA, and decreasing asphericity in eyes that underwent myopic laser refractive surgery.     

Prospective randomized comparison of wavefront-guided and conventional photorefractive keratectomy for myopia with the meditec MEL 70 laser

PURPOSE: To study refractive results and aberrometric changes in myopic patients treated with wavefront-guided photorefractive keratectomy (PRK) in comparison with standard PRK. METHODS: Sixty eyes of 60 patients with myopic astigmatism were randomly divided into two groups. Group 1 included 30 eyes (mean spherical equivalent refraction -4.39 +/- 1.31 D; range -2.50 to -6.50 D) treated with wavefront-guided PRK using the WASCA workstation and the Asclepion Meditec flying spot MEL 70 excimer laser. Group 2 had 30 eyes (mean spherical equivalent refraction -4.33 +/- 1.22 D; range -2.50 to -6.50 D) that underwent conventional PRK using the same laser, and served as the control group. Wavefront analysis of high order aberrations was performed before and 6 months after surgery. RESULTS: Postoperatively, wavefront error increased in both groups (5.0-mm wavefront aperture diameter). Six months after surgery, the eyes that received the WASCA ablation had a smaller increase in root-mean-square (RMS; 70% of increment) compared to the conventional PRK group (139% of increment) (P<.001). In the standard PRK group, all aberrations notably increased; in the wavefront-guided PRK group there was a smaller increase of trefoil and spherical aberrations (P<.001) and a decrease of coma aberrations (P<.001). The smaller increase of wavefront error in the wavefront-guided PRK group compared to the standard PRK group was more evident when preoperative RMS values were higher than 0.4 microm (P<.01). The visual parameters (spherical equivalent refraction, uncorrected and best spectacle-corrected visual acuity) did not show significant differences between the two groups. CONCLUSION: Wavefront-guided PRK induced a smaller increase of postoperative wavefront-error compared to conventional PRK, particularly in patients with higher preoperative higher order aberrations.     

Corneal sensation after laser epithelial keratomileusis for the correction of myopia

Background Subepithelial nerve fibre bundles and stromal nerves are damaged during laser epithelial keratomileusis (LASEK). The aim of this study was to investigate the recovery of corneal sensation after LASEK for the correction of myopia.Methods Corneal sensation was evaluated in 40 eyes of 20 patients using a Cochet–Bonnet aesthesiometer before surgery and 3 days, 14 days, 1, 3 and 6 months after LASEK for the correction of mild to moderate myopia (range –2.5 D to –8.0 D). At every examination corneal sensation was tested in the apex of the cornea and in one point each at the 12, 3, 6 and 9 o clock positions 2 mm from the centre of the cornea.Results Corneal sensation was significantly reduced at 3 days and 14 days after surgery (P<0.01). The loss of corneal sensation was greatest 3 days after surgery and corneal sensation increased during the first month after LASEK. After 1 month, 3 months and 6 months no significant difference was found between preoperative and postoperative sensation. There was no significant difference in sensation between different areas of the cornea after LASEK.Conclusions Corneal nerves are disrupted during LASEK surgery and the procedure results in a significant reduction in corneal sensation. During the first month after surgery the depressed corneal sensation improved and subsequently went back to preoperative values, staying stable 3 months and 6 months after surgery.     

Corneal irregular astigmatism after laser in situ keratomileusis for myopia

AIMS: To quantitatively evaluate the changes in corneal irregular astigmatism after laser in situ keratomileusis (LASIK) in relation to the amount of laser ablation. METHODS: In 189 eyes of 116 patients undergoing LASIK for myopia, corneal topography was obtained before and 1 month after surgery. Using Fourier harmonic analysis of the topography data, corneal irregular astigmatism (asymmetry and higher order irregularity) was calculated. RESULTS: By surgery, asymmetry component significantly increased (p < 0.0001, Wilcoxon signed rank test), while higher order irregularity did not (p = 0.767). The increases in the asymmetry component significantly correlated with ablation depth (Spearman rank correlation coefficient r(s) = 0.440, p < 0.0001). No significant correlation was found between changes in higher order irregularity and ablation depth (r(s) = 0.137, p = 0.074). CONCLUSION: LASIK significantly increases the asymmetry component of the cornea which is dependent on the amount of laser ablation.     

准分子激光角膜表层切削技术研究进展

准分子激光角膜表层切削技术不断发展,安全性更高是其相对于基质深层切削最大的优势.从以PRK为代表的传统表层切削发展到现今以LASEK和Epi-LASIK为主的改进的表层切削,两阶段主要区别在于上皮瓣的去留.而改进的表层切削中上皮瓣的制作方式也各有不同.上皮瓣对切削损伤后角膜的保护及调节作用正日益受到关注.本文就准分子激光角膜表层切削技术的演变和特点及对上皮瓣的研究情况进行综述.     

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.     

Wavefront-guided custom ablation for myopia using the NIDEK NAVEX laser system

PURPOSE: To determine the predictability, efficacy, safety, and stability of LASIK using custom ablation with the NIDEK Advanced Vision Excimer Laser System (NAVEX). METHODS: One hundred twenty eyes underwent LASIK for myopia using the OPDCAT algorithm. Refractive outcomes and the change in higher order aberrations, coma, and spherical aberrations were analyzed. Postoperative follow-up ranged from 6 to 18 months. RESULTS: Mean postoperative spherical equivalent refraction was -0.05 diopters (D) (range: -0.92 to +0.88 D). Uncorrected visual acuity was 1 or better in 109 (91%) eyes and 1.2 or better in 47 (39%) eyes. Postoperative spherical equivalent refraction was within +/- 0.50 D of intended correction in 110 (92%) eyes. Fifty-two (43%) eyes gained 1 or more lines of best spectacle-corrected visual acuity (BSCVA), and no eyes lost more than 1 line of BSCVA. Higher order aberrations root-mean-square increased by 0.053 microm postoperatively. Patients with preoperative higher order aberrations > or = 0.3 microm were less likely to have induced higher order aberrations. CONCLUSIONS: Wavefront-guided OPDCAT treatments with the NIDEK NAVEX system for myopia are safe and effective with excellent visual acuity and refractive outcomes. Eyes with > or = 0.3 microm of higher order aberrations preoperatively will benefit more from OPDCAT treatment than eyes with a smaller amount of higher order aberrations.     

Topographic changes after hyperopic LASIK with the SCHWIND ESIRIS laser platform

PURPOSE: To analyze and compare refractive power changes with topographic changes after hyperopic LASIK using the ESIRIS laser platform. METHODS: Sixty-six consecutive eyes of 37 patients were evaluated retrospectively. Outcomes were evaluated at 3 months. In all cases, standard examinations including pre- and postoperative topographic and corneal wavefront analysis with a Keratron topographer were performed. Preoperative mean spherical equivalent was +/- 2.74 diopters (D) with a mean cylinder of 0.67 D. The ESIRIS excimer laser system was used to perform ablations. Topographic changes of Maloney index, simulated keratometry (sim-K), and K-reading at 5 and 7 mm were evaluated. RESULTS: Ninety-two percent of eyes were within +/- 0.50 D manifest refraction at 3 months postoperatively. Changes in refraction, Maloney indices, and sim-K indices after surgery were strongly correlated with the intended correction. Induction of negative corneal spherical aberrations and increased prolate asphericity was correlated with the achieved defocus correction. No other Zernike mode was significantly correlated. Topographically, an overcorrection within the central 3 mm and a gradual peripheral undercorrection also was observed. CONCLUSIONS: Analyzing the topographic maps, the corneal power change of the Maloney indices correlated with the intended correction. After hyperopic LASIK, an overcorrection was observed in the 3-mm central zone, and progressive undercorrections were observed in the 5- and 7-mm zones.     

Aberration-sensing and wavefront-guided laser in situ keratomileusis: management of decentered ablation

PURPOSE: To clarify the feasibility of aberration-sensing and wavefront-guided laser in situ keratomileusis (LASIK) to manage grossly decentered ablation and to discuss the limitations of the technology. METHODS: Three patients with previous decentrations of the ablation zone between 1.5 to 2.0 mm were scheduled for wavefront-guided LASIK. All patients reported monocular diplopia and halos. Wavefront aberrations were measured with a Tscherning-type aberrometer. Laser ablation was done with a WaveLight Allegretto in a one-step procedure with ablation profiles calculated only from the individual wavefront map. Decentrations were determined from corneal topography. RESULTS: Three months after surgery, patient WM and patient SU had gained uncorrected and best spectacle-corrected visual acuity. The root mean square-wavefront error decreased up to 61% and 33%, respectively, for total and higher order aberrations (Zernike modes of 3rd order and higher). There was significant enlargement of the optical zone determined by corneal topography, and both patients no longer reported diplopia and halos at 3 months postoperatively. The optical aberration of the third patient (RE), after a 5.00-D overcorrection with a 2-mm decentration, was too high for aberration-sensing; retinal images obtained from the wavefront device were too smeared and not of sufficient contrast. In addition, this patient had a residual corneal thickness of 416 microm and thus wavefront-guided LASIK was not done. CONCLUSIONS: Wavefront-guided LASIK offers a new way of managing grossly decentered laser ablations. Unfortunately, there are still patients who have aberrations too large for wavefront sensing or with other clinical limitations such as a residual corneal thickness too thin for further treatment.     

Aspheric wavefront-guided versus wavefront-guided LASIK for myopic astigmatism with the Technolas 217z100 excimer laser

Purpose

To compare clinical outcomes of wavefront-guided LASIK with and without aspheric compensation in myopic eyes.

Methods

In this observational, single-center study, 134 eyes were treated using an aspheric module in combination with wavefront-guided profiles (PTA-algorithm) and compared to 146 eyes treated with the predecessor wavefront-guided software (APT) that has no aspheric compensation. All treatment plans included the Rochester nomogram that accounts for the preoperative manifest refraction and interaction of higher order aberrations. Active eye-tracking (including cyclorotational movements) was utilized during photoablation.

Results

Results at the 3-month follow-up: 67 % of PTA-treated eyes and 39 % of APT-treated eyes achieved an uncorrected distance visual acuity (UDVA) of 20/20 or better. Change in mean higher order aberration root-mean-square (HOA RMS) after PTA treatments was not statistically significant (p?=?0.18). The increase in HOA RMS after APT treatments was statistically significant (p?=?0.003). Change in mean postop spherical aberration (SA) after PTA treatments was not statistically significant (p?=?0.27). The change in SA after APT treatments was statistically significant (p?=?0.001). In both cohorts, mean uncorrected low-contrast visual acuity was statistically not different to preoperative corrected values.

Conclusions

Adding an aspheric compensation to wavefront-guided myopic LASIK statistically improved clinical results in terms of visual acuity and refractive outcomes. Low-contrast visual acuity was not negatively affected in either group. While in APT-treated eyes mean HOA RMS and mean SA were significantly increased postoperatively, PTA-treated eyes showed neither induced HOA RMS nor induced SA.     

波前像差引导的飞秒激光LASIK手术矫正高度近视的效果

目的:探讨波前像差引导的飞秒激光准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)手术矫正高度近视的效果。方法:随机选取2012-10/12在重庆爱尔眼科医院行波前像差引导的飞秒激光LASIK手术的高度近视患者(近视-6.0～-10.0DS,散光≤-2.0DC)32例58眼作为试验组。同期接受飞秒激光LASIK手术的高度近视患者(近视-6.0～-10.0DS,散光≤-2.0DC)28例56眼作为对照组。术后随访6mo,比较两组的裸眼视力(uncorrected visual acuity,UCVA),屈光度数,总高阶像差(high order aberrations,HOA),球差和彗差。结果:术后6mo,所有患者UCVA均≥0.8,其中UCVA≥1.0者波前组91.4%,对照组87.5%,差异无统计学意义(P=0.360);UCVA≥1.2者波前组60.3%,对照组57.1%,差异无统计学意义(P=0.729);UCVA≥1.5者波前组17.2%,对照组12.5%,差异无统计学意义(P=0.477)。波前组的彗差低于对照组,差异有统计学意义(P=0.021)。两组UCVA,等效球镜度,总HOA和球差的比较无统计学差异(P>0.05)。结论:波前像差引导的飞秒激光LASIK手术与常规飞秒激光LASIK手术相比,虽然可以降低术后彗差的产生,但在提高术后UCVA,矫正高度近视度数,降低术后HOA和球差方面没有优势。     

Q值引导与波前引导的LASIK治疗近视的初步研究

目的:观察Q值引导与波前引导的LASIK治疗近视的疗效。方法:接受非球面切削与波前引导的LASIK治疗26例患者(52眼),每名患者的1眼使用Q值引导的切削,另1眼使用波前引导的个性化切削进行LASIK手术,分析2组的治疗效果。结果:术后3mo,2组手术眼视力矫正均满意,其间屈光度无差别(P>0.05);Q值引导组与波前引导组比较其术后角膜更倾向于长椭球形,Q值(0.24±0.32)低于波前引导组Q值(0.53±0.41)(P<0.01),当瞳孔直径为6mm时,两组术后高阶像差RMS均有增加,Q值引导组术后球差增加的幅度小于波前引导组,而彗差增加的幅度大于波前引导组。术后眩光发生率两组无显著性差异(P>0.05)。结论:使用Q值引导与波前引导的LASIK治疗近视及近视散光均是安全有效的,但仍存在不足,需要进一步改进、优化或整合。