LASIK前后眼压测量方法选择

目的 比较四种常用眼压计在近视准分子激光原位角膜磨镶术(Laserin situ eratomileusis,LASIK)前后的应用,探讨LASIK手术前后眼压测量方式的选择,以做到术前高眼压患者筛查及术后患者青光眼的早期发现.方法 对71例接受LASIK手术近视眼患者按等效球镜分为三组,分别在术前和术后1个月和3个月采用Schiotz眼压计(Schiotztonometer,ST)、Goldmann眼压计(Goldmann applanationtonometry,GAT)、非接触眼压计(non-contacttonometer,NCT)和Tono-Pen眼压计(TP)测量眼压,同时记录手术前后角膜中央厚度.结果 各屈光度组间同时间点相同眼压计测量值差异无统计学意义,术前除GAT、TP外其他眼压计差异有统计学意义,术后各眼压计测量值均降低,TP受角膜变化影响较小,GAT及NCT受影响明显,三者均与术前GAT值相关.ST不受角膜变化影响但其测量值明显偏高且术后与术前GAT无相关关系.结论 术前采用TP或GAT均可,术后应用TP,而NCT可作为术前筛查辅助手段.ST的应用仍有待探讨.     

LASIK术后非接触性眼压测定值的改变

目的:研究准分子激光原位角膜磨削术(laser·in situ keratomileusis,LASIK)术后非接触性眼压计(noncontact tonometer,NCT)测量值的准确性。方法:对180例(256只眼)近视患者行IASIK手术,手术前、后采用NCT测量患者的眼压,并测量角膜厚度和角膜曲率,进行统计学分析。结果:LASIK术后NCT测量值明显低于术前,差异有显著性(P<0.001),术后一年眼压下降(6.54±2.1)mmHg(1 mmHg=0.133 kPa)。术后一年眼压下降值与角膜厚度减少及角膜前表面曲率的降低有关(P<0.01),建立二元回归方程如下:Y=0.355+0.0342X1+0.365X2。Y:术前术后眼压差(mmHg),x1:术前术后角膜曲率差(D),x2:角膜切削厚度(μm)结论:LASIK术后NCT眼压测量值明显低于术前,术后所测量眼压与角膜切削厚度、角膜曲率有关。     

DCT和GAT对LASIK手术前后眼压的比较性研究

目的 评价动态轮廓眼压计(DCT)和Goldmann压平眼压计(GAT)对在准分子激光原位角膜磨镶术(LASIK)手术前后眼压测量值的变化.方法 取71例141只眼近视患者在LASIK术前和术后一周分别进行角膜厚度(CCT)、GAT、DCT测量.结果 ①LASIK手术前后DCT测得值尤显著性差异(P=0.062),GAT测得值有显著性差异(P＜0.001),CCT测得值有显著性差异(P＜0001).②Bland-Altman分析示LASIK手术前后DCT与GAT两种测量方法均呈现高度一致性.术前DCT测量值高于GAT测量值1.1mmHg,95%可信区间为(-0.6,2.8)mmHg;术后DCT测量值高于GAT测量值8.2mmHg,95%可信区间为(5.3,11.1)mmhg.③△GAT与△CCT呈正相关,△DCT与△CCT无统计相关性.结论 DCT测量值不受LASIK手术切削的影响,更适合于LASIK手术前后眼压的测量.     

准分子激光原位角膜磨镶术非接触眼压测量值分析

目的:探讨准分子激光原位角膜磨镶术(laserinsituker-atomileusis,LASIK)后眼压测量值的影响因素。方法:对1100例(2200眼)近视患者行LASIK并随访1a,记录手术前后的眼压值(非接触眼压测量)。结果:LAISK术后3,6,12mo的眼压值,均较术前有明显下降。结论:LASIK术后眼压测量值低于术前。角膜切削深度量的大小是影响术后眼压高低的重要因素。     

动态轮廓眼压计与压平眼压计的比较

目的:评价和比较动态轮廓眼压计和Goldmann压平眼压计测得的LASIK手术后眼压值。方法:接受准分子激光原位角膜磨镶术(LASIK)的近视患者34例68眼,分别于术前和术后3mo使用动态轮廓眼压计(Pascal dynamic contour tonometer,PDCT)和Goldmann压平眼压计(the Goldmann applanation tonometer,GAT)进行眼压测量。比较手术前后两种测量方法测得的眼压值的差异。多元线性相关分析研究GAT,PDCT测量值和角膜曲率及角膜中央厚度(CCT)之间的相关性。结果:LASIK手术后GAT测量值较术前低,而PDCT值和术前比较差异则无统计学意义。角膜曲率、CCT和GAT读数呈线性相关,而与PDCT读数无关。结论:GAT测量得到的眼压低于实际值。PDCT测眼压不受角膜曲率和中央角膜厚度影响。     

动态轮廓眼压计与非接触式眼压计的比较

目的探讨中央角膜厚度和角膜曲率对轮廓动态眼压计以及非接触式眼压计眼压测量结果的影响。方法接受准分子激光原位角膜磨镶术(LASIK)的近视患者27例(54只眼),分别于术前和术后第4周使用非接触式眼压计(NCT)和动态轮廓眼压计(DCT)进行眼压测量。多元线性相关分析研究NCT、DCT测量值和角膜曲率及角膜中央厚度(CCT)之间的相关性。结果LASIK术后NCT测量值降低,而DCT测量值和术前比较差异则无统计学意义。角膜曲率、CCT和NCT读数呈线性相关,而与DCT读数无关。结论DCT测量眼压不受角膜曲率和中央角膜厚度影响,因此更适合于正常眼以及曾经接受角膜屈光手术眼的眼压测量。     

准分子激光角膜原位磨镶术治疗近视术后眼压分析

目的探讨非接触性眼压计测量准分子激光角膜原位磨镶术(LASIK)治疗近视术后眼压变化及影响因素。方法选取-1.50-15.00D近视散光102例(198眼),每例按1眼参与分析,按预矫正等值球镜屈光度分为2组,Ⅰ组-1.50～6.00D56眼,Ⅱ组-6.25—15.0D42眼,用非接触眼压计测量术前及术后1月眼压,并分析术后眼压变化的因素。结果两组术后1月眼压均低于术前(P<0.05),术后随访1月以上显示高度组眼压降低幅度明显高于低中度组(P<0.05)。结论非接触性眼压计测量LASIK术后眼压值要进行修正,尤其在诊断青光眼或高眼压症时应慎重对待。     

准分子激光原位角膜磨镶术后眼压测量值的分析

目的：探讨准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后眼压测量值的影响因素。方法：对238例(473只眼)近视患者行LASIK并随访1年，记录手术前后的屈光度、角膜厚度、角膜曲率和眼压(非接触式眼压计测量)并进行统计学处理。结果：LASIK术后3、6、12个月的屈光度、角膜厚度、角膜曲率及眼压测量值均较术前明显下降，差异有非常显著意义(P＜0．0001)。术前及术后各时期的眼压测量值与角膜厚度、角膜曲率均呈正相关，而与屈光度无关。结论：LASIK术后眼压测量值低于术前，角膜厚度和角膜曲率是影响眼压测量值的两个重要因素。     

Diaton眼压计测量准分子激光原位角膜磨镶术后眼压

目的:通过与非接触式眼压计(non-contact tonometer,NCT)的比较,评价Diaton眼压计(DT)在准分子激光原位角膜磨镶术(laser in situkeratomileusis,LASIK)前后眼压测量中的应用价值。方法:在LASIK术前及术后1mo,分别使用NCT和DT测量患者眼压,使用SPSS13.0统计软件对所得结果进行统计学分析。结果:术后1mo时,NCT眼压测量值较术前下降(5.76±2.31)mmHg,DT眼压测量值则无显著差异(t=0.70,P=0.487);NCT与DT读数测量值差值与术中切削量呈正相关,与术后中央角膜厚度呈负相关。结论:Diaton测量眼压不受角膜厚度的影响,因此更适用于LASIK术后患者的眼压测量。     

PRK、LASIK术后非接触眼压测量值的准确性

目的 :评估准分子激光屈光性角膜切削术 (PRK)和准分子激光原位角膜磨镶术 (LASIK)后非接触眼压 (NCT)测量值的准确性。方法 :对 5 5例 (10 9只眼 )行PRK和 5 7例(113只眼 )行LASIK的近视患者进行回顾性分析 ,手术前、后采用非接触眼压计测量患者的眼压 ,并测量角膜厚度和角膜曲率 ,进行统计学分析。术后随访时间 >1年 ,停用激素至少半年以上。结果 :PRK和LASIK术后NCT测量值都低于术前 ,分别下降 (3.6 7± 1.6 5 )mmHg和 (5 .11± 1.5 1)mmHg ,差异有非常显著意义 (P <0 .0 0 1)。PRK和LASIK术前眼压测量值与角膜厚度均呈高度正相关 (P <0 .0 0 1) ;术后眼压测量值的降低与角膜厚度的减少高度正相关 (P <0 .0 5 ) ,其回归方程分别为 ^Y(手术前、后眼压差 ,mmHg) =1.36 1+0 .0 38X(手术前、后角膜厚度差 ,μm)和 ^Y =1.95 4 +0 .0 4 0X ;眼压测量下降值和角膜曲率的降低无关。结论 :PRK和LASIK术后眼压测量值均低于术前 ,角膜厚度是导致手术后眼压测量值减少的主要因素 ,且眼压测量值随角膜厚度的减少而下降。在临床工作中 ,应避免术后类固醇性青光眼因眼压测量值的下降而被漏诊。     

应用SPSS对近视LASIK术后非接触眼压变化的回归分析及模型验证

目的应用SPSS软件分析建立近视准分子激光原位角膜磨镶术（LASIK）术后非接触式眼压变化的回归模型,并对其进行效能检验。方法前瞻性分析性研究。筛选行近视LASIK的患者235例（470眼）,将左、右眼随机分入A、B 2组,每组各235眼。术前测量各眼的中央角膜厚度、平均角膜曲率、等效球镜度,通过与准分子激光主机相连的计算机计算消融深度、基质床厚度、消融比,术前及术后3个月时采用非接触式眼压计测量非接触式眼压（NCT）。对A组数据采用SPSS分析并建立预估近视LASIK术后眼压变化值的回归公式,将B组数据代入所得的回归公式及Schallhorn回归公式作模型验证及效能检验。结果纳入研究的470眼,术前NCT为（16.9±3.0）mmHg（1 mmHg=0.133 kPa）,术后3个月NCT为（11.6±2.3）mmHg,NCT下降了（5.3±2.5）mmHg。通过A组数据得到3个方程：?譹?訛△NCT=术前NCT×0.572-4.388（R2=0.496,F=229.1,P＜0.001）;?譺?訛△NCT=术前NCT×0.552+消融比×0.158-6.219（R2=0.561,F=148.4,P＜0.001）;?譻?訛△NCT=术前NCT×0.587+消融比×0.168-中央角膜厚度×0.011-1.103（R2=0.573,F=103.5,P＜0.001）。经B组数据检验,运用方程1、2、3所得△NCT预估值与实测值差异无统计学意义,用Schallhorn公式所得△NCT预估值与实测值差异有统计学意义（t=8.981,P＜0.001）。结论近视患者LASIK术后可建立预估△NCT的回归公式;和Schallhorn公式相比,此公式能更有效地预估LASIK术后NCT的变化。     

LASIK对非接触型眼压计测量眼压的影响

目的：分析准分子激光原位角膜磨镶术（ｌａｓｅｒ ｉｎ ｓｉｔｕ ｋｅｒａｔｏｍｉｌｅｕｓｉｓ,ＬＡＳＩＫ）治疗近视眼术后眼压的影响因素。方法：采用ＬＡＳＩＫ治疗２１４只近视眼。用非接触式眼压计测量术前、术后的眼压。对眼压与术前、术后各因素进行相关分析和多元逐步回归分析。结果：ＬＡＳＩＫ术后１月的眼压明显低于术前,差异具有显著性意义（ｓｔｕｄｅｎｔ ｔ检验,Ｐ〈０．０００１）。ＬＳＡＩＫ术后眼压的降     

A predictive model for postoperative intraocular pressure among patients undergoing laser in situ keratomileusis (LASIK)

PURPOSE: The aim of this study was to develop a predictive model based on preoperative variables for estimating postoperative intraocular pressure (IOP) of those eyes undergoing LASIK surgery, to predict the amount of underestimated IOP after LASIK for myopia and myopic astigmatism. DESIGN: Pretest-post-test longitudinal study. METHODS: Both eyes of 193 eligible subjects who underwent LASIK procedures at the Department of Ophthalmology, National Taiwan University Hospital, from July 2000 to December 2002 for myopia and myopic astigmatism were identified to build up the predictive models. IOPs were measured with noncontact air-puff tonometry. Information on age, gender, preoperative central corneal thickness (CCT), preoperative central corneal curvature (CCK), preoperative spherical equivalent refractive error, and ablation depth was collected and applied for predicting postoperative IOP after LASIK based on linear mixed model. RESULTS: Significant predictors for postoperative IOP after myopic LASIK procedures included age, gender, preoperative IOP, ablation depth, preoperative CCT, and preoperative spherical equivalent refractive errors. The linear mixed model, taking into account these significant preoperative correlates and the correlation of IOPs between both eyes of the same patient, explained 91% of the variation of postoperative IOP. CONCLUSIONS: A statistical model was developed for predicting the amount of underestimated IOP after LASIK for myopia and myopic astigmatism, which is of clinical importance to uncover ocular hypertension among patients whose information on postoperative IOP immediately after LASIK is not available.     

Change in intraocular pressure in myopic eyes measured with contact and non-contact tonometers after laser in situ keratomileusis

PURPOSE: To study the change in the intraocular pressure (IOP) after laser in situ keratomileusis (LASIK) for correction of myopia. METHODS: One hundred twenty consecutive myopic eyes (60 patients) were included in a prospective study. All eyes received LASIK with the Nidek EC-5000 excimer laser and the Chiron Automated Corneal Shaper. Baseline refraction, keratometry, pachymetry, ablation depth, and IOP measured by Goldmann applanation tonometry and non-contact air puff tonometry were correlated with the IOP change after surgery. Sixty healthy eyes of 30 subjects served as controls. RESULTS: At 6 months, 108 eyes (90%) were examined. Compared to preoperative values, IOP decreased in 103 eyes (95.4%) when measured with applanation tonometry; it decreased in all eyes when measured with air puff tonometry. Mean change in IOP was -4.3 +/- 2.1 mmHg (range, -10.0 to +1.0 mmHg) with the applanation and -6.1 +/- 2.3 mmHg (range, -12.0 to -1.0 mmHg) with air puff tonometry. The IOP change measured with either instrument correlated significantly with the baseline IOP (P < .001) and the ablation depth (air puff, P < .001, applanation; P = .006). CONCLUSION: Intraocular pressure decreased significantly after LASIK when measured with either Goldmann (mean 4.3 mmHg) or air puff (mean 6.1 mmHg) tonometers. This decrease may delay the diagnosis or affect the management of future glaucoma that may develop in a myopic eye that received LASIK.     

三种眼压计在准分子激光原位角膜磨镶术后的应用比较

目的评价三种不同眼压计在近视准分子激光原位角膜磨镶术后的应用。方法对近视33例66眼和LASIK术后43例86眼分别用非接触眼压计(non—contact tonometer NCT)，Goldmann压平眼压计(Godmann applanalion tonometer，GAT)和Tono-Pen压平眼压计测量眼压(Tono—Pen眼压计测量角膜中央和颞下距角膜缘1．5～2mm处的眼压)，同时测角膜中央及颞下方的厚度。结果用三种方法测得的近视眼LASIK术后的眼压测量值均明显低于正常近视眼。两组均为Tono—Pen和NCT、与GAT测量值呈正相关，LASIK术后中央Tbno—Pen眼压测量值与术前GAT呈正相关。眼压与角膜厚度的关系：近视眼组，NCT与角膜中央厚度呈正相关；GAT和Tono—Pen与角膜厚度无相关性。LASIK术后组，GAT和NCT与角膜厚度呈正相关；Tono-Pen与角膜中央厚度无相关性。结论LASIK术后眼压测量值下降。Tono—Pen测量IOP不受角膜厚度的影响，可应用于LASIK术后等角膜表面不平者。     

The preoperative intraocular pressure level predicts the amount of underestimated intraocular pressure after LASIK for myopia

AIMS: To evaluate the statistical significance of the parameters that affect underestimation of intraocular pressure (IOP) after laser in situ keratomileusis (LASIK) for myopia. METHODS: In this prospective case series study, patient age, axial length, preoperative corneal curvature, preoperative central corneal thickness (CCT), preoperative IOP, and ablation depth were studied to determine whether they affect the underestimation of IOP in the right eyes of 100 consecutive patients who underwent LASIK. RESULTS: The preoperative IOP was the most important parameter for an amount of underestimated Goldmann applanation tonometric IOP (GAT) and non-contact tonometric IOP (ncIOP) at 1 month (r = 0.654, p<0.0001, R(2) = 0.427, and r = 0.694, p<0.0001, R(2) = 0.481, respectively) and 3 months (r = 0.637, p<0.0001, R(2) = 0.406, and r = 0.726, p<0.0001, R(2) = 0.527, respectively). Patient age was statistically significant for underestimating the GAT at 1 month, and both the ablation depth and CCT were statistically significant parameters for underestimating the ncIOP at 1 month and at 3 months by stepwise multiple regression analysis (F>4.000). However, these parameters had small bivariate correlation coefficients, and were considered as minor parameters. CONCLUSION: Preoperative IOP is the most important parameter that affects an underestimation of IOP after LASIK for myopia. Eyes with a higher true IOP have a larger underestimation of the IOP after LASIK for myopia. From these results, the importance of the modulus of elasticity on IOP measurements was discussed.     

Intraocular pressure measurements using dynamic contour tonometry after laser in situ keratomileusis

PURPOSE: Thinning of the corneal stroma by laser in situ keratomileusis (LASIK) results in inaccurate low intraocular pressure (IOP) readings by Goldmann applanation tonometry (GAT). Dynamic contour tonometry (DCT) is a novel measuring technique, designed to measure IOP largely independent of corneal thickness and curvature. The purpose of this study was to compare IOP measurements using GAT and DCT in eyes undergoing LASIK for correction of myopia. METHODS: In a prospective, single-center study, central corneal thickness (CCT) and IOP were measured in patients undergoing first-time LASIK for myopia. IOP was measured before and after surgery using GAT and DCT. The untreated contralateral eyes served as paired controls. RESULTS: There was good concordance between the two tonometers in 62 normal eyes before LASIK. Corneal ablation of 90.0 +/- 49.18 micro m (median +/- SD) reduced IOP readings as measured by GAT by 3.0 +/- 1.9 mm Hg (P < 0.001). In contrast, no significant change in IOP readings was recorded by DCT (-0.2 mm Hg +/- 1.5 mm Hg, P = 0.30). There was no change in IOP in the untreated control eyes as measured by GAT and DCT. CONCLUSIONS: Significant decreases in IOP were recorded by GAT after LASIK for myopia. Measurements by DCT, however, did not reveal any significant changes in IOP.     

Changes in intraocular pressure after laser in situ keratomileusis

PURPOSE: To evaluate changes in intraocular pressure (IOP) measurements by Goldmann applanation tonometry after laser in situ keratomileusis (LASIK) for myopia and myopic astigmatism, and to assess the accuracy of Goldmann applanation tonometry measurements after LASIK in these eyes. METHODS: LASIK was performed on 166 eyes of 93 patients for correction of myopia and myopic astigmatism. Intraocular pressure was measured by Goldmann applanation tonometry at the central and temporal parts of the cornea before and at 1, 3, 6, and 12 months after LASIK. The amount of change in IOP was computed and its relation to different variables was evaluated by regression analysis. RESULTS: Intraocular pressure measured at the center of the cornea was reduced by a mean of 3.69 +/- 1.63 mmHg after LASIK. Multiple regression analysis showed that the decrease in IOP was related to the preoperative IOP and the change in central corneal thickness after LASIK. Measurements of IOP at the temporal part of the cornea were also reduced by a mean of 2.39 +/- 1.71 mmHg. There was wide variability in the amount of difference between the temporal and central measurements after LASIK (temporal measurements were higher than central by 0 to +4 mmHg). CONCLUSION: LASIK for myopia produced underestimation of IOP measured by Goldmann applanation tonometry at the central part of the cornea by a mean of 3.69 +/- 1.63 mmHg. The decrease of IOP was related to preoperative IOP and the change in central corneal thickness after LASIK. Temporal Goldmann applanation tonometry measurements, although decreased after LASIK, were less reliable.