应用GDx VCC检测原发性开角型青光眼视网膜神经纤维层

目的 采用GDx VCC检测青光眼和正常人视网膜神经纤维层厚度(retinal nerve fiber layer,RNFL),并进行对比分析.方法 选择正常人44人44眼,原发性开角型青光眼患者45例45眼行GDx VCC检查.将获取的参数(椭圆平均值、上方平均值、下方平均值、TSNIT标准差、眼间对称性、视神经纤维指征)进行分析.结果 所有参数在正常人组与青光眼组比较中均有统计学意义(P＜0.01).GDxVCC不同参数检测青光眼RNFL缺损敏感性为68.9%～82.2%,特异性84.1%～100.0%.其中下方平均值、视神经纤维指征ROC曲线下面积为0.959、0.964.结论 GDx VCC在RNFL检查中有较高的敏感性和特异性,可客观反应受检者的RNFL情况,对于青光眼的早期诊断有一定的临床价值.     

眼挫伤后视网膜神经纤维层厚度改变的研究

目的观察成人眼挫伤后的视网膜神经纤维层厚度变化。方法采用偏振光激光扫描仪(GDx神经纤维厚度分析仪)可变角膜补偿(VCC)模式分别对16例(16眼)成人眼挫伤后1周和3月进行视网膜神经纤维层厚度测量,并以对侧健康眼作对照。测量参数包括:颞侧、上方、鼻侧、下方、颞侧曲线(TSNIT)平均延迟、上方平均延迟、下方平均延迟、和神经纤维指数(NFI),对数据结果进行统计学分析。结果采用GDx_VCC模式于伤后1周和3月进行测量结果分别是:TSNIT平均延迟、上方平均延迟、下方平均延迟、以及神经纤维指数依次为,伤后1周:56.12±5.25μm,68.77±6.20μm,67.32±4.04μm,18.35±5.66;伤后3月:52.45±5.26μm,61.21±1.11μm,59.51±1.06μm,31.77±2.17。对侧健眼相对应的相关数据为57.45±6.33μm,69.21±2.56μm,68.14±3.06μm,17.27±7.15。结论GDx神经纤维层厚度分析仪的检查对于眼挫伤的随访观察是一个有价值的方法。可用于评估挫伤眼的病情和疗效。     

偏振激光扫描仪联合个体化角膜补偿技术对可疑青光眼的随访研究

目的 对临床可疑青光眼患者进行长期的偏振激光扫描仪联合个体化角膜补偿技术(scanning laser polarimetry with variable corneal compensation, GDx VCC)随访,分析GDx VCC对该类患者的诊断价值.方法 选取门诊可疑青光眼的眼底检查视乳头杯/盘比(C/D)≥0.4,或双眼不对称且C/D差值≥0.2,静态视野检查结果正常患者68例,随访前后均用GDx VCC检查(采用相同的角膜补偿值).如双眼C/D值相同,随机选取1眼,如C/D值不同,则选取C/D值大的1眼,对结果进行t检验统计学分析.结果 随访时间6～30个月,平均(12.5±7.0)个月,眼底C/D值为 0.57±0.17.随访前后GDx VCC 检查:椭圆平均值分别为50.33±7.72和49.66±8.12,上方平均值为58.72±13.56和58.18±12.01,下方平均值为60.71±11.31和59.13±11.95,神经纤维指数为30.85±19.62和33.03±21.22,差异无统计学意义,但从绝对数值上,椭圆平均值、上方平均值和下方平均值变小,神经纤维指数变大.其中7例(10.3%)诊断为青光眼, 21例(30.9%)排除青光眼,40例(58.8%)仍需进一步随访.结论 对临床怀疑青光眼的患者应长期进行随访,GDx VCC随访对青光眼的诊断有一定的价值.(中国眼耳鼻喉科杂志,2009,9:92-94)     

OCT检测视网膜神经纤维层厚度及视盘参数在青光眼早期诊断应用

目的 通过光学相干断层成像术(OCT)检测视网膜神经纤维层(RNFL)厚度及视盘结构参数,结合视野改变,探讨OCT在青光眼早期诊断中的应用价值.方法 采用OCT对34只眼疑似闭角型青光眼(SG)患者、36只眼慢性闭角型青光眼(CACG)早中期患者、10只眼正常人行RNFL及视盘扫描,观察各组的RNFL厚度及视盘结构的图像特征;将各象限RNFL厚度和平均RNFL厚度的均数进行总体比较及任意两组间比较;将视乳头水平、垂直杯盘比及杯/盘面积比的均数进行比较;将平均RNFL厚度与视野指数进行相关分析.结果 三组间各象限RNFL厚度、平均RNFL厚度、视盘参数差异有统计学意义(P<0.05);正常人与SG组下方、上方及平均RNFL厚度差异有统计学意义(P<0.05);正常人与CACG早中期组各象限RNFL厚度及平均RNFL厚度差异均有统计学意义(P<0.05);CACG早中期组与SG组上方、下方、鼻侧及平均RNFL厚度差异有统计学意义(P相似文献   

中央角膜厚度与视网膜神经纤维层厚度关系在正常眼和高眼压患者之间的比较研究

目的通过角膜中央厚度分组,观察正常眼和高眼压患者的角膜厚度和视网膜神经纤维层（RNFL）厚度之间的关系,并通过相干光断层扫描成像（OCT）和偏振激光扫描仪联合个体化角膜补偿技术（GDx-VCC）检查高眼压患者是否存在RNFL的异常,并分析OCT和GDx-VCC测得的RNFL厚度之间的相关性。方法对眼压高于21 mm Hg（1 mm Hg=0.133 kPa）的患者测量其中央角膜厚度（CCT）,根据CCT值对眼压进行校正。OCTOPUS-101自动视野仪检查及视盘观察入选高眼压组患者180只眼,均予OCT、GDx-VCC测量视盘一周视网膜神经纤维层厚度,另设正常人180只眼作为对照,获得数据进行统计学分析。结果高眼压患者的平均CCT为（536.14±35.99）（433～609）μm,正常组患者的平均CCT为（516.68±38.27）（368～598）μm。根据平均中央角膜厚度555μm分组,组间平均视网膜神经纤维层厚度（Average RNFL）、上方（S）、下方（I）的RNFL厚度以及其它参数有显著性差异,高眼压组CCT≤555μm的患者平均视网膜神经纤维层厚度要低于CCT〉555μm的患者。结论高眼压患者RNFL厚度GDx-VCC与OCT的检测值低于正常人。高眼压组CCT与平均视网膜神经纤维层厚度正相关。GDx-VCC与OCT有着较好的一致性。     

青光眼视网膜神经纤维损害激光偏振光扫描测量的价值

目的:探讨青光眼的视网膜神经纤维层缺损特征,评价激光偏振光扫描测量仪(GDxVCC)在青光眼早期诊断方面的应用价值。方法:采用激光偏振光扫描测量仪(GDxVCC,美国)对60例110眼正常人及46例85眼青光眼患者视网膜后极部水平方向40°、垂直方向20°范围进行激光偏振光扫描测量视网膜神经纤维层厚度(RNFL),同时进行中央30°视网膜光阈值检查(Humphrey视野分析仪,Central30-2thresholdtest,美国),并对结果进行统计分析。结果:正常眼RNFL厚度与性别、眼别无关,而与年龄呈负相关;各期青光眼患者的RNFL均值显著低于正常对照组(年龄匹配,P<0.01);早期、进展期、晚期青光眼患者的RNFL厚度均值比较也有显著性差异(P<0.001)。GDxVCC检测RNFL厚度值与Humphrey视野检查指数平均缺损值(MD)具显著正相关性(r=0.795,P<0.001)。青光眼的视网膜神经纤维层图像可表现为局限性变薄或缺损(85.2%)、弥漫性变薄(6.6%)、弥漫性变薄并局限性缺损(8.2%),以鼻上方的局限性变薄或缺损最常见(56.7%)。有23.3%的早期青光眼患者视野检测正常而GDxVCC检测发现有不同程度的视网膜神经纤维层缺损。结论:GDxVCC能准确定量检测RNFL厚度值,视网膜神经纤维层的检测能比视野检测更早地发现青光眼的视神经的损害,因而可作为青光眼患者早期诊断的重要指标之一。随着青光眼患者病情的发展,RNFL厚度逐渐变薄,视野的平均缺损值逐渐增加。GDxVCC联合视野检查对于追踪青光眼患者的病情变化,确立靶眼压的水平,制定个性化的治疗方案有着重要的价值。     

角膜中央厚度与原发性开角型青光眼视网膜神经纤维层厚度的关系

目的:研究原发性开角型青光眼患者的角膜中央厚度(central corneal thickness,CCT)与开角型青光眼严重程度之间的关系。方法:对眼科门诊原发性开角型青光眼患者30例60眼分别进行视野,OCT检查中央角膜厚度及视神经纤维层厚度,并进行统计学分析。结果:研究组中开角型青光眼患者的平均中央角膜厚度为561.8±44.9(483～609)μm。根据同一患者双侧中央角膜厚度分组,组间视野平均缺损(MD),平均视神经层厚度(average retinal nerve fiber layer,Average RNFL)有显著性差异(P=0.034,P=0.012),CCT较薄组MD值及平均视神经层厚度均较低。CCT与MD,平均视网膜神经纤维层厚度正相关(P=0.043,P=0.006)。结论:中央角膜厚度与开角型青光眼视神经损伤有一定相关性。     

近视眼视网膜神经纤维层厚度分析

目的:分析近视眼患者与正常人视网膜神经纤维层厚度的差异,探讨近视程度对视网膜神经纤维层厚度的影响。方法:采用视神经分析仪-GDxVCC(美国激光技术诊断公司生产)测量正常人23例42眼和近视眼患者85例166眼视网膜神经纤维层厚度,近视眼患者按等效球镜屈光度分为低、中、高、超高度近视四组,将所得结果用SPSS11.5统计软件包进行统计分析。结果:视乳头周围2.4～3.2mm的环形区域视网膜神经纤维层平均厚度正常人与低、中、高度及超高度近视组比较无显著性差异,不同程度近视眼组两两之间进行比较无显著性差异;上方120°区域视网膜神经纤维层厚度高度、超高度近视眼组与其他各组进行比较有非常显著性差异(P<0.01),高度与超高度近视组之间进行比较有显著性差异(P<0.01),其他各组两两之间进行比较无显著性差异;下方120°区域视网膜神经纤维层厚度各组之间进行比较无显著性差异;环形区域RNFL厚度平均值的标准差超高度近视组与其余各组之间的差异具有显著性(P<0.05);神经纤维指数高度近视组、超高度近视组与其他各组差异有显著性,且与屈光度呈线性关系(P<0.05)。结论:随着近视程度的增加,近视眼患者上方120!范围内视网膜神经纤维层厚度逐渐变薄,神经纤维指数逐渐增加。     

海德堡视网膜断层扫描仪在开角型青光眼视盘检测中的意义

目的 探讨海德堡视网膜断层扫描仪(HRT)检测开角型青光眼视盘参数与视野损害的关系。评价HRT在早期诊断青光眼中的意义。方法 正常人26例(41只眼)，高眼压11例(16只眼)、原发性开角型青光眼28例(38只眼)。采用Humphrey全自动视野计、HRT分别进行视野、视盘形态检测。比较正常组、高眼压组、青光眼组HRT视盘检测参数．分析青光眼组视野检测的平均缺损(MD)与HRT视盘检测参数的关系。结果 正常组、高眼压组、青光眼组视杯面积、杯／盘面积比、盘沿面积、视杯形态测量指数、视网膜神经纤维层厚度差异有显著性。青光眼组的盘沿面积、杯／盘面积比、视杯形成测量指数、视网膜神经纤维层厚度与视野检测的平均缺损有显著相关。结论 HRT能够反映青光眼视盘改变，为临床早期诊断青光眼提供更多的信息。     

对疑似高眼压症者视神经相关参数的分析研究

目的：研究正常者与疑似高眼压症者眼底视神经相关参数的差异性。

方法：分别对疑似高眼压症组36眼,正常眼压对照组43眼的各部位视网膜神经纤维层厚度(pRNFL)、视盘相关参数、黄斑区神经节细胞复合体厚度(mGCCT)及视野指数进行测定,对其所测结果进行对比分析。

结果：正常组与疑似高眼压症组的平均、上方及下方视网膜神经纤维层厚度,视盘相关参数(盘沿面积,视杯容积,平均杯盘比)相比均有显著性差异(P<0.01),黄斑区上方、下方及平均神经节细胞复合体厚度相比有显著性差异(P<0.01); 鼻侧视网膜神经纤维层厚度差异有统计学意义(P<0.05),颞侧视网膜神经纤维层厚度、视盘面积、平均变异(MD)和模式标准差(PSD)相比无显著性差异(P>0.05)。

结论：疑似高眼压症者的平均、上、下方及鼻侧视网膜神经纤维层厚度,视盘相关参数(盘沿面积,视杯容积,平均杯盘比),黄斑区上方、下方及平均神经节细胞复合体厚度与正常人相比发生了改变。     

GDxVCC系统检测视网膜神经纤维层在青光眼早期诊断中的价值

目的 比较正常人和不同程度青光眼患者GDxVCC系统检测RNFL参数的不同,评价GDx各参数的敏感性、特异性,探讨GDxVCC系统检测视网膜神经纤维层在青光眼早期诊断中的价值.方法 对35例(35只眼)原发性开角型青光眼、33例(33只眼)慢性闭角型青光眼、27例(27只眼)急性闭角型青光眼以及年龄相匹配的36人(36只眼)正常人进行GDxVCC系统和静态视野检查.GDxVCC系统检查,视盘周围视网膜神经纤维层(retinal nerve fiber layer,RNFL)任一参数与系统内所附中国正常人数据库对比概率＜5%或NFI＞30或视网膜神经纤维标准偏差图上连续有10个超级像素概率＜5%定义为具有青光眼性视网膜神经纤维层结构损害,并判断为青光眼.结果 22只正常眼被判断为非青光眼(61.1%),82只青光眼被判断为青光眼(86.3%),RNFL参数椭圆平均值、上方平均值、下方平均值、TSNIT标准偏差、神经纤维指数,标准偏差图诊断青光眼的敏感性分别为48.4%、56.8%、48.4%、50.5%、62.1%,特异性分别为97.2%、100%、97.2%、94.4%、97.2%、61.1%.GDxVCC系统诊断早期、中期、晚期青光眼的敏感性分别为77.36%、95.83%、100%.结论 GDxVCC系统诊断早期青光眼的敏感性和特异性均高,而且RNFL参数中神经纤维指数的敏感性最高.

Abstract：

Objective To evaluate the usefulness of the scanning laser polarimeter with variable corneal compensation (GDxVCC) for glaucoma detection in a Chinese population,and to investigate the retinal nerve fiber layer (RNFL) thickness difference between normal subjects and glaucoma patients.Methods Thirty-six eyes of 36 normal subjects,33 eyes of 33 primary chronic angle-closure glaucoma patients,27 eyes of 27 primary acute angle-closure glaucoma and 35 eyes of 35 primary open-angle glaucoma patients were studied.The glaucoma patients were age-matched with the normal.The thickness of retinal nerve fiber layer was measured with GDxVCC.An eye was diagnosed as glaucoma,ifone of the parameters showed P＜0.05 on the results of the examination reports including four TSNIT parameters (the average of TSNIT,superior,inferior,and TSNIT Std.Dev.),nerve fiber indicator (NFI) ＞ 30,and at least 10 consecutive defects of superpels showed in deviation map (P ＜0.05).Results Of 22 normal eyes (61.1%) were diagnosed as non-glaucoma and 82 glaucomatous eyes (86.3%) were diagnosed as glaucoma by GDxVCC.Sensitivity of the average of TSNIT,superior,inferior,TSNIT Std.Dev.,NFI and the deviation map were 48.4%,56.8%,48.4%,50.5%,62.1% respectively and specificity were 97.2%,100%,97.2%,94.4%,97.2% and 61.1% respectively.Sensitivity of detection early,moderate and progression glaucoma by GDxVCC were 77.36%,95.83%,100% respectively.Conclusions GDxVCC is a valuable technology to detect retinal nerve fiber layer defect in early glaucoma.It is shown that the NFI has highest sensitivity.     

Scanning laser polarimetry with variable corneal compensation and optical coherence tomography in normal and glaucomatous eyes

PURPOSE: To evaluate the relationship between visual function and retinal nerve fiber layer (RNFL) measurements obtained with scanning laser polarimetry with variable corneal compensation (SLP-VCC) and optical coherence tomography (OCT). DESIGN: Cross-sectional analysis of normal and glaucomatous eyes in a tertiary care academic referral practice. METHODS: A commercial GDx nerve fiber analyzer was modified to enable the measurement of corneal polarization axis and magnitude so that compensation for corneal birefringence was eye specific. Complete examination, SLP with fixed corneal compensation (FCC) and variable corneal compensation (VCC), optical coherence tomography (OCT) imaging of the peripapillary RNFL, and automated achromatic perimetry were performed in all subjects. Exclusion criteria were visual acuity less than 20/40, diseases other than glaucoma, and unreliable perimetry. RESULTS: Fifty-nine patients (59 eyes; 29 normal, 30 glaucomatous) were enrolled (mean age, 56.7 +/- 20.3 years, range, 20-91). All eyes with glaucoma had associated visual field loss (average mean defect, -8.4 +/- 5.8 dB). Using SLP-FCC, nine of 12 retardation parameters (75%) were significantly less in glaucomatous eyes. Using SLP-VCC, 11of 12 retardation parameters (92%) were significantly less in glaucomatous eyes. Multiple regression models constructed for each retardation parameter with visual field demonstrated that the following VCC parameters were statistically significant whereas FCC parameters were not: ellipse average (FCC, P =.28, VCC, P =.001), superior average (FCC, P =.38, VCC, P <.001), inferior average (FCC, P =.10, VCC, P =.008), average thickness (FCC, P =.30, VCC, P =.031), and superior integral (FCC, P =.43, VCC, P =.001). Similar results were obtained for multiple regression models constructed with OCT-derived RNFL thickness: ellipse average (FCC, P =.99, VCC, P =.002), superior average (FCC, P =.90, VCC, P <.001), inferior average (FCC, P =.61, VCC, P =.007), and superior integral (FCC, P =.92, VCC, P <.001). CONCLUSIONS: Compared with fixed compensation, mean-based SLP parameters generated with SLP-VCC have greater correlation with visual function and RNFL thickness assessments obtained with OCT.     

GDxVCC检测原发性开角型与可疑青光眼视网膜神经纤维层损害的对比研究

目的采用GDxVCC系统检测正常人、可疑开角型青光眼(suspected open angle glaucoma，SOAG)以及原发性开角型青光眼(primary open angle glaucoma，POAG)患者的视盘周围视网膜神经纤维层(retinal nerve fiber layer，RNFL)厚度，并进行对比分析，探讨GDxVCC系统在青光眼早期诊断中的价值。设计前瞻性对照研究。研究对象42例SOAG，36例POAG以及年龄相匹配的36例正常人参加此项研究。方法所有参加者进行视野与GDxVCC系统检查，选择一眼进行分析。采用方差分析，对SOAG、POAG、正常人的RNFL参数进行两两比较。主要指标GDxVCC检测RNFL厚度。结果POAG组与正常组问所有RNFL参数差异均有极显著意义(P=0．000)；POAG组与SOAG组间所有RNFL参数差异均有极显著意义(P=0．000)；SOAG组与正常组间椭圆平均值差异无统计学意义(P=0．234)，但其上方平均值与下方平均值及神经纤维指数差异均有统计学意义(P=0．044、P=0．045、P=0．035)，TSNIT标准差有极显著意义(P=0．000)。结论GDxVCC系统能更早地发现青光眼性RNFL结构损害，不仅可用于青光眼诊断和随访，亦可用于对可疑青光眼进行追踪。     

The relationship between optical coherence tomography and scanning laser polarimetry measurements in glaucoma

PURPOSE: To investigate the relationship between optical coherence tomography (OCT) and scanning laser polarimetry (SLP) in measuring peripapillary retinal nerve fiber layer (RNFL) thickness in glaucomatous eyes. METHODS: Fifty glaucomatous eyes were evaluated in this study. Evaluations were analyzed two ways. First, parameters of the Stratus OCT (average thickness, superior/inferior average) and GDx VCC (TSNIT average, nerve fiber indicator (NFI), superior/inferior average) were correlated using the Pearson's correlation coefficient (r). Secondly, comparison (r) of these parameters was completed using the mean deviation (MD) of visual field defect. RESULTS: The following parameters were found to be significantly correlated (P < 0.005). TSNIT average/average thickness (r = 0.673), NFI/average thickness (r = -0.742), superior average (r = 0.841), and inferior average (r = 0.736). In the correlation analysis using the severity of visual field defect, all these parameters had statistically meaningful correlations (P < 0.005). CONCLUSIONS: GDx VCC and Stratus OCT are highly correlated in glaucomatous eyes. Therefore, peripapillary RNFL thickness measured by Stratus OCT and GDx VCC may be equally helpful in the diagnosis of glaucoma.     

Intersession reproducibility of retinal nerve fiber layer thickness measurements by GDx-VCC in healthy and glaucomatous eyes

BACKGROUND: To assess intersession reproducibility of retinal nerve fiber layer (RNFL) thickness measurements on scanning laser polarimetry with variable corneal compensation (GDx-VCC) in a sample of healthy subjects and glaucoma patients. METHODS: One eye each from 29 healthy and 29 glaucomatous subjects was selected and underwent RNFL scanning by the same operator at baseline and 1 week later. Glaucoma diagnosis relied on the presence of a reproducible defect on automated perimetry. GDx-VCC parameters considered were those available on page 1 of the printout [TSNIT average and standard deviation (SD), superior and inferior average (SA, IA), Nerve Fiber Indicator]. Reproducibility was assessed by calculating coefficient of variation and intraclass correlation coefficient separately for the two groups and for each parameter. The percentage of eyes with an intersession difference in thickness parameters of more than 5% was also calculated. RESULTS: Coefficient of variation was <6% for TSNIT average, SA and IA in both groups. Corresponding values for TSNIT SD in healthy subjects and in glaucoma patients were 13.7 and 11.4%, respectively, whereas for Nerve Fiber Indicator they were 82.9 and 13.3%. Intraclass correlation coefficient ranged from 0.794 to 0.907 in healthy subjects and from 0.924 to 0.972 in glaucoma patients. In healthy subjects, TSNIT average, SA and IA intersession difference was 5% or less in 55-69% of eyes, whereas the value for TSNIT SD was 34.5%. Corresponding values in glaucomatous eyes ranged from 69 to 79.3% for TSNIT average, SA and IA and was 37.9% for TSNIT SD. CONCLUSIONS: Intersession reproducibility of RNFL thickness measurements on GDx-VCC is high, both in healthy and in glaucomatous eyes. In a few cases, however, intersession variation may be larger than 10%. Caution is necessary while interpreting these changes during follow-up, in order to separate physiological variability from real RNFL thickness variations.     

Scanning laser polarimetry with enhanced corneal compensation and optical coherence tomography in normal and glaucomatous eyes

PURPOSE: To examine the association between scanning laser polarimetry (SLP), using enhanced (ECC) and variable corneal compensation (VCC) with optical coherence tomography (OCT), and to compare their discriminating ability in the diagnosis of glaucoma. METHODS: Normal and glaucomatous eyes enrolled from four clinical sites underwent complete examination, automated perimetry, SLP-ECC, SLP-VCC, and OCT. Eyes were characterized in two groups based on the typical scan score (TSS): Normal birefringence pattern (NBP) was defined as a TSS of 80 to 100 and abnormal birefringence pattern (ABP) as TSS 相似文献   

Correlating structure with function in end-stage glaucoma.

BACKGROUND AND OBJECTIVE: To correlate structure and function in eyes with end-stage glaucoma. PATIENTS AND METHODS: Fifty-six eyes of 48 patients with glaucoma presenting with end-stage glaucoma underwent scanning laser polarimetry (SLP) imaging using a commercially available GDx-variable corneal compensator unit (GDx-VCC; Laser Diagnostics Technologies, Inc., San Diego, CA). End-stage glaucoma was defined by both disc appearance and standard automated perimetry visual field criteria. Standard automated perimetry parameters included: mean deviation, pattern standard deviation, and total deviation plot. GDx parameters included: TSNIT average, superior average, inferior average, TSNIT standard deviation, and nerve fiber indicator. RESULTS: The visual field mean deviation was -26.75 +/- 3.50 dB. The remaining retinal nerve fiber layer measured in this group of eyes was: TSNIT average, 29.76 +/- 5.81 microm; superior average, 30.76 +/- 6.25 microm; and inferior average, 31.14 +/- 7.20 microm. A low structure-function correlation was found when analyzing separately the superior and inferior hemifields (R2 = 0.00001, R2 = 0.0016, respectively). CONCLUSIONS: In eyes with end-stage glaucoma, very thin but existing retinal nerve fiber layer is found on SLP. Such values rarely dropped below 10 to 20 microm. A flattening of the GDx TSNIT pattern was seen, and the correlation between structure and function was not evident.     

The retinal nerve fibre layer thickness in glaucomatous hydrophthalmic eyes assessed by scanning laser polarimetry with variable corneal compensation in comparison with age‐matched healthy children

Purpose: To compare the thickness of the retinal nerve fibre layer (RNFL) in hydrophthalmic glaucomatous eyes in children with age‐matched healthy controls using scanning laser polarimetry with variable corneal compensation (GDxVCC). Methods: Twenty hydrophthalmic eyes of 20 patients with the mean age of 10.64 ± 3.02 years being treated for congenital or infantile glaucoma were included in the analysis. Evaluation of RNFL thickness measured by GDxVCC in standard Temporal‐Superior‐Nasal‐Inferior‐Temporal (TSNIT) parameters was performed. The results were compared to TSNIT values of an age‐matched control group of 120 healthy children published recently as referential values. The correlation between horizontal corneal diameter and RNFL thickness in hydrophthalmic eyes was also investigated. Results: The mean ± SD values in TSNIT Average, Superior Average, Inferior Average and TSNIT SD in hydrophthalmic eyes were 52.3 ± 11.4, 59.7 ± 17.1, 62.0 ± 15.6 and 20.0 ± 7.8 μm, respectively. All these values were significantly lower compared to referential TSNIT parameters of age‐matched healthy eyes (p = 0.021, p = 0.001, p = 0.003 and p = 0.018, respectively). A substantial number of hydrophthalmic eyes laid below the level of 5% probability of normality in respective TSNIT parameters: 30% of the eyes in TSNIT average, 50% of the eyes in superior average, 30% of the eyes in inferior average and 45% of the eyes in TSNIT SD. No significant correlation between enlarged corneal diameter and RNFL thickness was found. Conclusions: The mean values of all standard TSNIT parameters assessed using GDxVCC in hydrophthalmic glaucomatous eyes in children were significantly lower in comparison with referential values of healthy age‐matched children.     

Central corneal thickness correlated with glaucoma damage and rate of progression

PURPOSE: To evaluate whether the amount of glaucomatous optic nerve damage at presentation of the patient and the rate of progression of glaucoma during follow-up are related to central corneal thickness. METHODS: The prospective observational clinical study included 861 eyes of 454 white subjects (239 normal eyes of 121 subjects, 250 ocular hypertensive eyes of 118 patients, 372 eyes of 215 patients with chronic open-angle glaucoma). For 567 eyes (304 patients) with ocular hypertension or chronic open-angle glaucoma, follow-up examinations were performed, with a mean follow-up time of 62.7 +/- 33.2 months (median, 60.8; range, 6.2-124.9). All patients underwent qualitative and morphometric evaluation of color stereo optic disc photographs and white-on-white visual field examination. Central corneal thickness was measured by corneal pachymetry. RESULTS: Central corneal thickness correlated significantly (P < 0.001) and positively with the area of the neuroretinal rim and negatively with the loss of visual field. Development or progression of glaucomatous visual field defects detected in 119 (21.0%) eyes was statistically independent of central corneal thickness, in univariate (P = 0.99) and multivariate Cox regression analyses (P = 0.19). CONCLUSIONS: At the time of patient referral, the amount of glaucomatous optic nerve damage correlated significantly with a thin central cornea. Progression of glaucomatous optic nerve neuropathy was independent of central corneal thickness, suggesting that central corneal thickness may not play a major role in the pathogenesis of progressive glaucomatous optic nerve damage.     

Polarimetric measurement of retinal nerve fiber layer thickness in glaucoma diagnosis

PURPOSE: To evaluate reliability and diagnostic value of polarimetric measurements of the retinal nerve fiber layer (RNFL) thickness in the diagnosis of glaucoma. METHODS: The study included 81 eyes with perimetric glaucoma with glaucomatous changes of the optic disc and visual field defects; 52 eyes with preperimetric glaucoma with glaucomatous optic disc abnormalities and normal achromatic visual fields; and 70 normal eyes. For determination of reliability, four examiners repeated polarimetric measurements five times in ten normal subjects. RESULTS: The polarimetric variables were significantly correlated with increasing mean visual field defect and decreasing neuroretinal rim area. In correlation analyses with visual field defects, correlation coefficients were highest for the variable "superior/nasal ratio" and "the Number," a variable calculated by the neural network of the device. In correlations with neuroretinal rim area, correlation coefficients were highest for measurements of the inferior nerve fiber layer thickness. The preperimetric glaucoma group and the control group differed significantly in the variables "superior/nasal ratio" and "the Number" and, to a smaller degree, in the variables "superior/temporal ratio" and "superior/inferior ratio." The Number variable had a sensitivity of 82% and 58% at a predefined specificity of 80% in separating perimetric glaucoma patients and preperimetric glaucoma patients, respectively, from control subjects. Reproducibility of the polarimetric measurements ranged between 70% and 89%. CONCLUSION: Polarimetric measurements of the RNFL thickness can detect glaucomatous optic nerve damage in patients with visual field loss, and in some patients with preperimetric glaucomatous optic nerve damage. Considering the fast performance, easy handling, and low maintenance costs, RNFL polarimetry may be helpful in glaucoma diagnosis.