LASIK后角膜后表面曲率变化的研究

目的 研究准分子激光原位角膜磨镶术(LASIK)手术前后角膜后表面前凸的变化,探讨手术后应保留角膜的安全厚度.方法 将135例269只眼近视患者依据近视程度分为3组,使用Orbscan裂隙扫描角膜地形图/角膜测厚系统,观察3组LASIK手术前后角膜后表面差值(Diff)的变化.结果 术前3组Diff值1组为(0.023±0.008)mm;2组为(0.024±0.010)mm;3组为(0.024±0.010)mm,平均值为(0.024±0.009)mm,各组间比较,差异无显著性意义(P＞0.05).厚度＞500μm的角膜后表面Diff值为(0.023±0.008)mm,厚度＜500 μm的角膜后表面Diff值为(0.035±0.014)mm,两组相差非常显著(P＜0.001).术后3组Diff值均较术前增大,1组为(0.052±0.014)mm;2组为(0.052±0.018)mm;3组为(0.053±0.018)mm,平均值为(0.052±0.017)mm,术前术后两组比较相差非常显著(P＜0.001).术后根据保留角膜厚度不同分3组,1组保留角膜厚度＞450 μm,Diff值为(0.041±0.008)mm;2组保留角膜厚度为410～450 μm,Diff值为(0.057±0.013)mm;3组保留角膜厚度为＜410 μm;Diff值为(0.080±0.014)mm.3组间比较,差异均非常显著.术后保留角膜床厚度＞280 μm者,角膜后表面前凸值为(0.016±0.005)mm;术后保留角膜床厚度＜280 μm,角膜后表面前凸值为(0.034±0.009) mm;角膜后表面前凸值平均为(0.017±0.006)mm.结论 术前角膜后表面Diff值与近视程度无关,而与角膜厚度有关,较薄的角膜后表面前凸程度较厚的角膜明显.LASIK术后角膜后表面中央部均有不同程度的前凸.保留角膜床厚度和角膜后表面前凸值呈负相关.LASIK后角膜厚度至少应在410 μm,残留角膜床厚度安全值应为280 μm.     

薄角膜的近视散光眼行准分子激光原位角膜磨镶术后角膜生物力学状态长期观察

目的探讨薄角膜(500μm)近视散光眼行准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后长期(≥60个月)的角膜生物力学状态、手术的安全性、有效性及准确性。方法选取1998年9月至2010年9月,行LASIK手术且资料完整的薄角膜患者89例175只眼,观察术前及术后末次的裸眼视力(uncorrected visual acuity,UCVA)、矫正视力(corrected distance visual acuity,CDVA)、球镜度数、散光度数、等效球镜度数(spherical equivalent,SE),以及术前的中央角膜厚度(central corneal thickness,CCT)及术后末次复查时的CCT、角膜瓣厚度与剩余基质床厚度(residual stromal bed thickness,RSBT)及角膜地形图。计算安全指数、有效指数、准确性以及角膜瓣厚度+切削深度)/术前中央角膜厚度(Percent Tissue Altered,PTA)与剩余基质床厚度/术前中央角膜厚度(Percentage stromal bed thickness,PSBT)结果安全指数为1.09,有效指数为0.99,末次复查的SE在±0.50D、±1.00D范围之内的百分比分别为71.2%、87.7%,PTA为20%~55%(40%±6%),PSBT为51%~85%(61%±9%),无术眼发生继发性圆锥角膜。结论 PSBT达到50%及以上时,薄角膜(459~499μm)近视散光眼行LASIK术后角膜生物力学状态长期稳定,且安全有效。     

RTVue傅立叶OCT与超声角膜测厚仪测量LASIK术前角膜厚度的对比研究

 目的 探讨RTVue傅立叶域光学相干断层成像系统(fourier domain optical coherence tomography,FD-OCT)与超声角膜测厚仪(ultrasonic pachymeter,USP)测量LASIK术前患者中央角膜厚度(corneal central thickness,CCT)的差异和可重复性.方法 选取近视患者800例(1600眼),分别应用RTVue-OCT和USP进行CCT测量.按等值球镜屈光度和USP测得角膜厚度不同各分4组,比较两种仪器测量值的差异和相关性.随机选择60例(60眼)用两种仪器依次重复测量CCT3次,对两种仪器重复测量值的标准差均值进行配对t检验.结果 RTVue-OCT和USP测得的CCT平均值分别为(528.47±29.84)μm和(537.89±30.56)μm,差异有统计学意义(P<0.01).OCT与USP测量值呈线性正相关(r=0.921,P<0.001),二者的相关公式为OCT测量值=2.2492×USP测量值0.8678.OCT和USP的CCT重复测量的标准差平均为3.87和6.38,差异有统计学意义(P<0.01).结论 RTVue傅立叶OCT的测厚功能与超声测量具有良好一致性,可重复性好,故可作为角膜厚度测量的工具之一,并可作为LASIK术前、术后综合分析观察的方法.     

LASIK前后非接触眼压计测眼压的临床观察

目的：探讨准分子激光原位角膜磨镶术(LASIK)前后非接触眼压测量值的变化。方法：对LASIK240例(450眼)手术前后采用非接触眼压计测量眼压，随访6个月以上，将术前和术后眼压的平均值及屈光度与角膜切削深度和眼压下降的关系进行比较分析。结果：450眼术前平均眼压16．53mmHg，术后6个月平均眼压9．27mmHg；角膜切削深度35～160μm，平均90μm；平均切削深度为78μm组的平均眼压下降6．4mmHg，平均切削深度为120μm组的平均眼压下降8．3mmHg。结论：LASIK术后眼压测量值比术前明显下降，术后仍应注意防治高眼压和青光眼。     

角膜非球面切削术的基质预留量对角膜形态稳定性的影响

目的观察非球面切削准分子激光原位角膜磨镶术（非球面LASIK）及准分子激光原位角膜磨镶术（普通LASIK）术后患者的临床疗效,探讨角膜非球面切削术的基质预留量对角膜形态稳定性的影响,为临床非球面LASIK预留安全的角膜基质厚度提供理论依据。方法按照患者意愿将患者分为非球面LASIK和普通LASIK两组,每组再按照预留基质多少分为350μm以上、300～350μm及280～299μm三组。不同术式两组术前各项指标均相似,差异无统计学意义。利用博士伦Orbscan II检测术后1周,1个月,1年,3年及5年角膜前曲率及Q值。主要指标统计非球面LASIK与普通LASIK术后第1周,1个月,1年,3年及5年进行复查各组的角膜前曲率及Q值等变化。结果非球面LASIK比普通LASIK术后Q值的变化更小。眼球的角膜曲率变化在两种术式的术后三年检查中均没有显著差异。两组均未发现屈光回退及圆锥角膜的发生。结论与普通LASIK相比,非球面LASIK能保持更好的角膜非球面形态。两组术式在预留基质280μm以上时,均是安全的。     

眼前节诊断系统与超声测量角膜厚度的比较

 目的 探讨眼前节诊断系统(ALLEGRO Oculyzer)与超声角膜测厚仪(ultrasonic pachymeter,USP)测量LASIK术前近视患者中央角膜厚度(corneal central thickness,CCT)的差异和可重复性.方法 选取近视患者232例(464只眼),分别应用Oculyzer和USP测量CCT.结果 Oculyzer和USP测得的CCT平均值分别为(541.09±34.03) μm和(541.07±34.71) μm,二者差异无统计学意义(P＞0.05).Oculyzer与USP测量值呈线性正相关(r=0.96,P<0.001).Oculyzer和USP的CCT重复测量值分别3.97±2.10和5.08±3.14,两者比较差异有统计学意义(P<0.001).结论 Oculyzer眼前节诊断系统的测厚功能与超声测量结果一致,可重复性好,可作为角膜厚度测量的工具之一.     

角膜波前像差引导的个性化LASIK手术后角膜像差变化的临床研究

目的 观察角膜波前像差引导的个性化准分子激光原位角膜磨镶术(LASIK)手术治疗近视后角膜像差变化情况及其与术前预矫屈光度的相关性.方法 按自愿选择非随机原则,将行准分子激光手术治疗的55例101只眼分为两组,其中22例40只眼接受常规小光斑飞点扫描LASIK手术(常规组),另33例61只眼接受基于ORK-CAM软件角膜波前像差引导的个件化LASIK手术(个性化组).记录两组患者术前和术后7d的裸眼视力、最佳矫正视力、残留屈光度;Optikon 2000角膜地形图仪测量术前和术后7 d球差、彗差、总体像差均方根值(RMS).结果 术前常规组平均届光度等效球镜值为(-5.27±2.04)D,个性化组为(-4.48±1.92)D;术后7 d常规组裸眼视力为0.96±0.21,平均残留屈光度为(0.97±0.63)D;个性化组视力为1.02±0.20,平均残留屈光度为(0.86±0.71)D,两组之间差异无显著意义.术前两组角膜球差、彗筹和RSM值差异均无显著意义.术后7 d球差、彗差值增加量在两组间差异有显著意义(P<0.05,P<0.01),RMS差异无显著意义(P>0.05),术后球差、彗差值增加量个性化组均低于常规组.两组术后球差增加量与术前屈光度数呈显著负相关(相关系数分别为r=0.823、-0.876,P<0.01),彗差值增加量与术前屈光度数亦呈负相关(相关系数分别为r=0.310、-0.345,P<0.05),总像差RMS与术前屈光度数在常规切削组呈正相关(相关系数为r=0.348,P<0.05),而在个性化组呈显著正相关(相关系数为r=0.787,P<0.01).结论 角膜波前像差引导的个性化切削LASIK手术后球差、彗差值增加量均小于常规组,与术前预矫屈光度数相关性亦较常规组为佳,具有良好的稳定性和可预测性.     

LASIK术中制作超薄角膜瓣治疗中高度近视的疗效观察

目的 探讨LANK术中制作超薄角膜瓣治疗中高度近视的可行性和疗效.方法 将138例276只眼屈光度为-3.50～-14.25 D的近视患者随机分为A组(常规厚度角膜瓣组)60例138只眼和B组(超薄角膜瓣组)60例138只眼.两组均使用Visx Star s4准分子激光仪进行激光切削.对两组术前最佳矫正视力(BCVA)、术中角膜瓣厚度、术后1周和1、3年裸眼视力(UCVA)及角膜瓣相关并发症进行比较.结果 术前BCVA A组为0.97±0.10,B组为0.95±0.12,差异无显著意义(P＞0.05);术中A超测量角膜瓣厚度A组为(118.12±13.83)μm,B组为(96.75±15.27)μm,差异有显著意义(P＜0.01);术中两组均无游离瓣、纽扣瓣、角膜瓣破裂出现,术后角膜瓣均对位良好,无角膜瓣融解、上皮植入等现象发生;术后1周UCVA A组为1.12±0.20,B组为1.10±0.23,差异无显著意义(P＞0.05);术后1年UCVA A组为1.10±0.24,B组为1.07±0.21,差异无显著意义(P＞0.05);术后3年UCVA A组为1.09±0.25,B组为1.04±0.22,差异无显著意义(P＞0.05).结论 LASIK术中制作超薄角膜瓣治疗中高度近视可行,疗效可靠.     

共焦显微镜对LASIK术后远期角膜组织改变的临床观察

目的应用共焦显微镜在细胞水平观察准分子激光原位角膜磨镶术(LASIK)术后远期角膜组织的形态学改变。方法选择1999年4月~2004年7月行LASIK手术的患者34例(68眼),年龄24·17±5·93岁(18~42岁),术前球镜-6·81±2·88D(-3·0~-16D),于术后39±3个月(6~73个月)时进行共焦显微镜观察。结果LASIK术后远期68眼(100%)中央角膜微皱折、异常颗粒长期存在,且不随时间延长而减少;中央角膜可见低细胞区,其基质深度为44·01±10·67μm。角膜瓣与角膜基质床呈非瘢痕性愈合。中央角膜神经纤维能够达到形态学修复。结论LASIK术后远期角膜稳定性未见明显改变,该术式安全可行。     

准分子激光双面式切削原位角膜磨镶术治疗近视的临床研究

准分子激光原位角膜磨镶术（LASIK）因其术后视力恢复快、屈光状态稳定、矫正范围大、术后疼痛小等优点成为目前临床上应用最广泛的矫正屈光不正的手术方式。但是对于近视度数较高而角膜相对偏薄的患者，LASIK术后有可能出现医源性圆锥角膜，这种并发症表现为进行性的角膜中央膨出。可能的诱发因素有患者的年龄、术前眼内压、角膜厚度、切削深度、切削区直径的大小、矫正的屈光度及手术保留的瓣下角膜厚度等，     

Live integration of comprehensive cardiac CT with electroanatomical mapping in patients with refractory ventricular tachycardia

BackgroundAim of the present study was to verify the feasibility and accuracy of live integration of myocardial fibrosis evaluated at CCT with EAM (electro-anatomical mapping).MethodsWe prospectively enrolled a consecutive cohort of patients with clinical indication to EAM before radiofrequency catheter ablation (RFCA) of refractory ventricular tachycardia (VT) and an absolute contraindication to cardiac magnetic resonance. All patients underwent per protocol CCT for myocardial fibrosis and coronary anatomy evaluation. Diagnostic performance was assessed for myocardial fibrosis evaluation with CCT vs EAM. Live integration feasibility of CCT vs EAM was evaluated for every patients.ResultsA total of 19 patients were included in the present study with 323 myocardial segments analyzed for myocardial fibrosis at CCT. In all patients CCT data were successfully integrated with EAM during RFCA procedure. All patients had myocardial fibrosis correctly identified at CCT vs EAM on a per-patients basis. A diagnostic accuracy on a per-segment basis of 94.1% for detection of any type of myocardial fibrosis at CCT vs EAM was recorded.ConclusionsCCT identification of myocardial fibrosis is feasible and accurate vs EAM in a very selected high risk patients with clinical indication to RFCA of VT and contraindication to CMR.     

Immediate renal tumor involution after radiofrequency thermal ablation

PURPOSE: To retrospectively evaluate solid renal tumor sizes before and after treatment with radiofrequency (RF) thermal ablation to assess for immediate changes on cross-sectional imaging. MATERIALS AND METHODS: Medical records were retrospectively reviewed in consecutive patients who underwent percutaneous image-guided RF thermal ablation for solid renal tumors between December 12, 2000, and December 13, 2006. All patients underwent noncontrast computed tomography (CT) immediately before and after RF ablation. Maximum renal tumor diameters were measured before and after ablation. Statistical analysis of tumor sizes before and after ablation and change in tumor sizes was performed with the paired Student t test with confidence intervals calculated. RESULTS: Seventy-two renal tumors were treated with RF ablation in 66 patients (42 men, 24 women; mean age, 68.4 years; range, 25-88 y). Mean tumor sizes were 27.5 mm (range, 9.8-64.8 mm; 95% CI, 24.9-30.1 mm) before ablation and 22.1 mm (range, 5.3-67.3 mm; 95% CI, 19.4-24.8 mm) immediately after ablation. An average decrease in renal tumor size of 21% (range, -10% to 50%) was identified, with a mean tumor diameter decrease of 5.4 mm (P < .05; 95% CI, 4.4-6.4 mm). No relationship between size or location of tumors and percentage decrease in size after RF ablation was identified. Measurement of tumors on 1-month follow-up CT showed no appreciable change compared with immediate postprocedural measurements. CONCLUSIONS: Renal tumors decrease in size immediately after treatment with RF thermal ablation. Immediate tumor involution after RF ablation should be anticipated and follow-up imaging studies should ideally be compared to a baseline tumor size measured as soon as possible after ablation.     

Multimodality imaging of left atrium in patients with atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia worldwide associated with significant morbidity and mortality and represents a significant health care burden. Goals of AF treatment include prevention of cardioembolic stroke using anticoagulation and device therapy and restoration of sinus rhythm using antiarrhythmic drugs or catheter ablation techniques. A comprehensive assessment of cardiac chamber size and function is often started with echocardiography as a first line diagnostic imaging strategy. Recently, innovations in advanced imaging using cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) provide a detailed characterization of atrial anatomy and have been shown to accurately exclude thrombus and guide left atrial appendage (LAA) closure or catheter ablation (CA) of atrial fibrillation. Compared to echocardiography, CCT offers an uncompromised spatial resolution and a fast dataset acquisition, with the disadvantages of the need of iodine contrast agent and radiation exposure. CMR, conversely, can rely on very high temporal resolution, the unique feature of tissue characterization and the absence of radiation exposure. However, the main drawbacks of this diagnostic tool are long scan times and low availability. This review will illustrate the vital role of multimodality cardiac imaging in the accurate identification of left atrial, pulmonary vein and LAA size and function, discuss advanced imaging techniques to rule out thrombus and highlight novel CMR and CCT techniques to guide catheter ablation of AF and LAA occlusion.     

Image-guided Thermal Ablation of Tumors Increases the Plasma Level of Interleukin-6 and Interleukin-10

PurposeTo identify changes in plasma cytokine levels after image-guided thermal ablation of human tumors and to identify the factors that independently predict changes in plasma cytokine levels.Materials and MethodsWhole-blood samples were collected from 36 patients at three time points: before ablation, after ablation (within 48 hours), and at follow-up (1–5 weeks after ablation). Plasma levels of interleukin (IL)-1α, IL-2, IL-6, IL-10, and tumor necrosis factor (TNF)-α were measured using a multiplex immunoassay. Univariate and multivariate analyses were performed using cytokine level as the dependent variable and sample collection, time, age, sex, primary diagnosis, metastatic status, ablation site, and ablation type as the independent variables.ResultsThere was a significant increase in the plasma level of IL-6 after ablation compared with before ablation (9.6-fold±31-fold, P<.002). IL-10 also showed a significant increase after ablation (1.9-fold±2.8-fold, P<.02). Plasma levels of IL-1α, IL-2, and TNF-α were not significantly changed after ablation. Cryoablation resulted in the largest change in IL-6 level (>54-fold), whereas radiofrequency ablation and microwave ablation showed 3.6-fold and 3.4-fold changes, respectively. Ablation of melanomas showed the largest change in IL-6 48 hours after ablation (92×), followed by ablation of kidney (26×), liver (8×), and lung (6×) cancers. Multivariate analysis revealed that ablation type (P<.0003) and primary diagnosis (P<.03) were independent predictors of changes to IL-6 after ablation. Age was the only independent predictor of IL-10 levels after ablation (P< .019).ConclusionsImage-guided thermal ablation of tumors increases plasma levels of IL-6 and IL-10, without increasing plasma levels of IL-1α, IL-2, or TNF-α.     

Directional Microwave Ablation: Experimental Evaluation of a 2.45-GHz Applicator in Ex Vivo and In Vivo Liver

PurposeTo experimentally characterize a microwave (MW) ablation applicator designed to produce directional ablation zones.Materials and MethodsUsing a 14-gauge, 2.45-GHz side-firing MW ablation applicator, 36 ex vivo bovine liver ablations were performed. Ablations were performed at 60 W, 80 W, and 100 W for 3, 5, and 10 minutes (n = 4 per combination). Ablation zone forward and backward depth and width were measured and directivity was calculated as the ratio of forward to backward depth. Thirteen in vivo ablations were performed in 2 domestic swine with the applicator either inserted into the liver (80 W, 5 min, n = 3; 100 W, 5 min, n = 3; 100 W, 10 min, n = 2) or placed on the surface of the liver with a nontarget tissue placed on the back side of the applicator (80 W, 5 min, n = 5). The animals were immediately euthanized after the procedure; the livers were harvested and sectioned perpendicular to the axis of the applicator. In vivo ablation zones were measured following viability staining and assessed on histopathology.ResultsMean ex vivo ablation forward depth was 8.3–15.5 mm. No backward heating was observed at 60 W, 3–5 minutes; directivity was 4.7–11.0 for the other power and time combinations. In vivo ablation forward depth was 10.3–11.5 mm, and directivity was 11.5–16.1. No visible or microscopic thermal damage to nontarget tissues in direct contact with the back side of the applicator was observed.ConclusionsThe side-firing MW ablation applicator can create directional ablation zones in ex vivo and in vivo tissues.     

Changes in choroidal thickness in myopic children with 0.01% atropine: Evidence from a 12-month follow-up

PurposeTo investigate the changes of low-dose atropine (0.01%) on the choroidal thickness (ChT) of young children with low myopia.MethodsA total of 25 eyes of 25 low myopic children were included. All subjects were prescribed 0.01% atropine eye drops to be applied once per night before bedtime in involving eyes. The ChT and ocular biometry parameters were measured before and after 1 month, 3 months, 6 months and 12 months. The children were followed up for 12 months.ResultsAt 3 months, the ChT under the fovea significantly increased (309.96±70.82 μm) in comparison with the baseline (297.92±66.31 μm, P<0.0001) and was continuous thickening till 12 months after treatments with 0.01% atropine. Similarly, the changes of ChT under the fovea significantly increased from baseline to 3 months in comparison with the baseline to 1 month after treatments (P<0.0001). There was a significant relationship between changes in subfoveal ChT and central cornea thickness (CCT, beta=−1.76, 95% confidence intervals: −3.49 to −0.04, P = 0.045).ConclusionsUsing low dose atropine eye drops significantly increased subfoveal ChT after 3 months in eyes of myopic children. In addition, the changes in subfoveal ChT may be associated with the changes of CCT.     

Comparison of two imaging protocols for acute stroke: unenhanced cranial CT versus a multimodality cranial CT protocol with perfusion imaging

The aim of the study was to validate a multimodality cranial computed tomography (CCT) protocol for patients with acute stroke in the United Arab Emirates as a basic imaging procedure for a stroke unit. Therefore, a comparative study was conducted between two groups: retrospective, historical group 1 with early unenhanced CCT and prospective group 2 undergoing a multimodality CCT protocol. Follow-up unenhanced CCT>48 h served as gold standard in both groups. Group 1: Early unenhanced CCT of 50 patients were evaluated retrospectively, using Alberta Stroke Program Early CT Score, and compared with the definite infarction on follow-up CCT. Group 2: 50 patients underwent multimodality CCT (unenhanced CCT, perfusion studies: cerebral blood flow, cerebral blood volume, mean transit time and CT angiography)<8 h after clinical onset and follow-up studies. Modified National Institute of Health Stroke Scale was used clinically in both groups. Group 1 showed 38 men, 12 women, clinical onset 2-8 h before CCT and modified National Institute of Health Stroke Scale 0-28. Group 2 included 38 men, 12 women, onset 3-8 h before CCT, modified National Institute of Health Stroke Scale 0-28. Sensitivity was 58.3% in group 1 and 84.2% in group 2. Computed tomography angiography detected nine intracranial occlusions/stenoses. The higher sensitivity of the multimodality CCT protocol justifies its use as a basic diagnostic tool for the set-up of a first-stroke unit in the United Arab Emirates.     

DWI应用于兔VX2肝癌模型HIFU治疗的价值

目的研究兔VX2肝癌模型在高强度聚焦超声(HIFU)治疗前后肿瘤扩散的变化。材料与方法 45只兔VX2肝癌模型HIFU治疗前及HIFU治疗后1、3、7、14、21天5个观测点进行磁共振扩散加权成像(DWI),观察术后5个观测点肿瘤与术前表观扩散系数(ADC)值的变化,并与病理结果对照分析。结果兔VX2肝癌模型HIFU术后1、3、7、14、21天,ADC图上呈高信号的肿瘤病理为坏死组织,ADC值较术前相应区域升高(P<0.05);术后3、7、14、21天,ADC图上呈混杂信号的肿瘤,高信号区病理为坏死组织,ADC值较术前相应区域升高(P<0.05);而低信号区病理为肿瘤组织,ADC值较术前相应区域无差异性(P>0.05)。结论磁共振DWI ADC值能够准确反映兔VX2肝癌模型HIFU治疗后的肿瘤坏死组织及存活组织,并能够作为HIFU治疗兔VX2肝癌疗效的重要监测手段。     

准分子激光上皮瓣下角膜磨镶术对晶状体密度的影响

目的探讨准分子激光上皮瓣下角膜磨镶术(LASEK)的激光切削时间、激光切削深度和患者术前屈光度数对晶状体密度的影响。方法 83例患者154只眼行LASEK手术,分为高、中、低3个年龄组,利用Pentacam眼前节分析仪测量患者双眼LASEK术前1 d和术后6个月晶状体密度,并测量患者术前屈光度数、激光切削时间和切削深度,进行t检验和相关性分析。结果三组患者手术前后晶状体密度差异无显著性意义(P>0.05)。低、中年龄组患者激光切削时间、切削深度和屈光度数与晶状体密度改变相关,尤其是低年龄组患者激光切削时间和激光切削深度与晶状体密度改变相关呈显著正相关(P<0.01),低、中年龄组术前屈光度数与晶状体密度改变呈负相关(P<0.05)。而高年龄组患者激光切削时间、深度和术前屈光度与晶状体密度改变无显著相关性。结论虽然激光切削时间、切削深度和屈光度数与晶状体密度存在高度相关性,但LASEK术后短期内对晶状体密度影响不大,说明LASEK手术是一种安全性比较高的手术,但术后的长期安全性仍须进一步研究。