兔眼视网膜厚度的光学相干断层扫描测量与组织学检查的相关性研究

目的 探讨兔眼视网膜厚度的光学相干断层扫描(optical coherence tomography,OCT)检测与组织学检查结果的相关性。 方法 采用OCT对16只兔眼视网膜进行扫描,然后对相应部位的视网膜作组织切片检查。OCT成像截面采用人工辅助(需要检查者对反射界面进行人工定位)和电脑自动测量两种方法进行分析。 结果 两种OCT检查法测得的视网膜厚度与组织学检查结果有良 好的相关性。OCT人工辅助检查法(γ＝0.84,P＜0.001)较电脑自动测量方法(γ＝0.66,P＜0.01)的相关性略好。前者测量的误差范围( 95%可信限)较小,在－2．99～5.13μm之间,而后者则高达11.09μm。 结论 OCT能准确定量检测兔眼视网膜厚度;部分OCT成像截面可能因电脑机械测量而产生误差,通过人眼识别给予矫正后能提高检查的准确性。 （中华眼底病杂志,2000,16：71-138）     

频域OCT对正常人和青光眼光感受器细胞层厚度的检测

背景青光眼以视网膜内层的神经节细胞丢失为主要病理特征,但其是否累及视网膜外层尚有争议。部分研究认为青光眼将导致视网膜外层（光感受器）功能的异常,而病理学研究得出了不同的结论。目的用频域OCT测量正常人和青光眼患者光感受器细胞层的厚度,探讨青光眼对光感受器细胞层厚度的影响。方法采用病例对照研究。用频域OCT（SDOCT）对正常人38例38眼和青光眼患者48例48眼的黄斑区进行扫描,由一位检测者采用Sigma图像分析软件盲法测量黄斑中心凹和旁中心凹处（中心凹外1．5mm）视网膜光感受器层的厚度。同时采用时域OCT（Stratus OCT）测量所有检测眼的视盘周围视网膜神经纤维层（RNFL）厚度,比较正常组和青光眼组光感受器细胞核层的平均厚度,分析光感受器细胞层厚度与RNFL厚度的关系。结果正常组和青光眼组在黄斑中心凹光感受器细胞核层厚度分别是（96．7±10．7）μm、（103．7±13．3）μm,差异有统计学意义（P=0．011）;中心凹光感受器内节和外节层厚度分别是（59．3±5．5）μm、（59．5±5．5）μm,差异无统计学意义（P=0．890）。正常组和青光眼组在中心凹外3mm处光感受器细胞核层厚度分别是（70．9±14．0）μm、（68．7±10．7）μm,光感受器内节和外节层厚度分别为（45．2±6．4）μm,（43．6±5．5）μm,差异均无统计学意义（P=0．410,P=0．228）。黄斑中心凹处光感受器细胞核层厚度和RNFL厚度两者有二元线性关系（γ=-0．019X。＋2．73X＋10．34,R^2=0．211,P=0．005）。结论青光眼的黄斑中心凹光感受器细胞核层显著增厚,并随病程的变化而改变。     

频域光学相干断层扫描对C57BL／6小鼠及色素兔眼前后节结构特点的活体观察

背景频域光学相干断层扫描（SD—OCT）可进行活体组织的测量。目前SD—OCT对人眼活体组织测量的研究已有较多报道,但对实验动物眼的活体测量结果少有研究。目的应用SD—OCT活体观察正常C57BL／6小鼠的眼前节结构及色素兔的角膜、视盘及视网膜形态结构。方法利用轴向分辨率为5μm、扫描速度为26000次／s的SD—OCT对4只健康SPF级C57BL／6小鼠8只眼扩瞳前后进行眼前节形态学检查;利用SD—OCT对6只健康SPF级色素兔12只眼进行角膜及视盘、视网膜形态学检查。结果SD—OCT进行眼前节扫描,清晰可见C57BL／6小鼠角膜、虹膜及瞳孔区对应的晶状体结构,而且扩瞳前后晶状体结构形态发生明显改变,角膜SD—OCT扫描断层图与相应的切片图结构相对应,扩瞳前平均中央角膜厚度（CCT）为（96±9）μm,平均前房深度（ACD）为（460-e8）汕m,平均角膜水平直径（wTw）为（2．86±0．41）mm;扩瞳后CCT为（96±8）μm,ACD为（356±20）μm,wTW为（2．87±0．62）mm,C57BL／6小鼠扩瞳前后CCT、wTw测量值的比较差异均无统计学意义（t=0．478,P=0．647;t=0．737,P=0．485）;扩瞳后ACD较扩瞳前明显变浅,差异有统计学意义（t=-13．022,P〈0．001）。色素兔的SD—OCT眼前节检查均可见明显的角膜及视网膜分层,结构分别与相应的组织学切片相对应,扩瞳后角膜最薄点均值为（370±10）μm,视网膜厚度均值为（175：e4）Ixm,水平扫描后手动测量数据视盘深度均值为（1．35±0．51）mm,宽度均值为（4．52±0．82）mm。结论SD—OCT作为一种非接触、非侵人性检查,可清晰呈现C57BL／6小鼠眼前节结构及色素兔相应的角膜和视网膜结构,测量指标可用于实验研究过程中相应组织结构的活体观察。     

高度近视眼黄斑体积的分区测定

目的:应用光学相干断层成像(OCT)技术研究高度近视眼黄斑部视网膜神经上皮层体积的变化。方法:将高度近视眼68例68眼和正常对照者59例59眼分为高度近视组和对照组,OCT测量黄斑中心凹最薄处神经上皮层厚度以及后极部视网膜地形图各个区域体积,比较两组结果的差异性。结果:高度近视眼组黄斑中心凹最薄处神经上皮层厚度145.7±20.2μm,正常对照组为151.9±26.7μm,两者差异无显著性(P=0.276)。高度近视眼组黄斑部视网膜神经上皮层体积为6.761±0.579mm3,正常对照组为7.262±0.508mm3,高度近视眼组黄斑体积明显小于正常组(P=0.006)。结论:OCT能够对黄斑部神经上皮层体积进行分区精确测量,可以作为研究高度近视眼后极部视网膜变化的手段之一。     

高度近视眼黄斑区神经上皮层厚度的OCT检测研究

目的探讨高度近视眼黄斑区视网膜神经上皮层厚度的变化。方法选取200／年5月至2007年12月在我院就诊并行光学相干断层扫描（OCT）检查的高度近视眼患者64例（64只眼）和正常对照者铝例（48只眼），分为高度近视组和正常对照组，测量其黄斑中心凹、中心凹上下方及颞侧、鼻侧各750μm处的视网膜神经上皮层厚度，比较两组有无显著性差异。结果高度近视组的黄斑区视网膜神经上皮层厚度均低于正常对照组，二者差异有显著意义（P〈0．01）。结论高度近视眼黄斑区视网膜神经上皮层厚度明显低于正常眼，OCT能够精确量化测定该厚度变化。     

远视性单眼弱视患者黄斑区视网膜厚度的研究

目的通过检测远视性单眼弱视者弱视眼黄斑区视网膜厚度（MRT）,研究弱视眼视网膜神经上皮层厚度的特征。方法远视性单眼弱视患者42例,正常组单眼远视但无弱视者20例。采用光学相干断层扫描仪（OCT）测量弱视眼和正常眼的MRT。结果弱视眼黄斑中心凹厚度比正常眼厚（P=0．005）,对于黄斑部位的分区测量,黄斑中心区厚度弱视眼比正常眼厚（P=0．010）,而黄斑周围外环及内环各象限弱视眼和正常眼相比差异均无统计学意义（P〉0．05）。不同程度弱视患者问黄斑中心凹及黄斑各分区的视网膜厚度差异均无统计学意义（P〉0．05）。结论远视性单眼弱视眼黄斑中心区视网膜厚度增厚,不同程度弱视眼间的视网膜厚度差异无统计学意义。     

OCT和FFA联合检测对中心性浆液性脉络膜视网膜病变发病机制的研究

背景以往中心性浆液性脉络膜视网膜病变（CSC）的确诊主要依靠荧光素眼底血管造影（FFA）,而光学断层相干扫描（OCT）与FFA的联合应用为CSC的动态观察及评价其发病机制提供了新的途径。目的通过将CSC患者的FFA图像导人OCT中,研究2种检查方法定位病变部位的一致性,探讨CSC的发病机制。方法44例单眼诊断为CSC的患者纳入本研究,包括男36例,女8例;年龄（39．34±5．3）岁,视力0．64±0．27。所有患者均进行了FFA和OCT检查。在Topcon3DOCT1000中导人FFA图像,直接对照OCT病灶与FFA渗漏点,观察二者病变部位的一致性,并用OCT方法测量中心凹神经上皮厚度及其脱离高度。结果OCT显示视网膜色素上皮（RPE）的改变包括RPE脱离34例（77．3％）,RPE小隆起和粗糙10例（22．7％）;在RPE脱离的34眼中OCT与FFA定位一致者占31例31眼（91．2％）,2种结果不一致者为3例3眼（8．8％）。OCT检测CSC患眼中心凹神经上皮层的厚度为（138．5±19．40）μm,与正常眼的（137．35±5．01）μm比较,差异无统计学意义（t=0．39,P〉0．05）;神经上皮层脱离的高度为（263．34±126．7）μm。结论CSC的病理机制为RPE脱离继发黄斑区神经上皮脱离,FFA渗漏点基本与OCT所测RPE脱离的部位相对应。无RPE脱离者可能与RPE通透性改变有关,OCT能精确测量中心凹神经上皮厚度及脱离的高度。     

视网膜中央静脉阻塞黄斑水肿玻璃体腔注射曲安奈德后视网膜电图明视负向反应变化

背景玻璃体腔注射曲安奈德（TA）对于视网膜中央静脉阻塞（CRVO）患者黄斑区水肿的消退以及视力的维持和提高作用较明显,明视负向反应（PhNR）可以反映视网膜内层视网膜神经节细胞（RGCs）及其轴突的功能,两者间是否存在联系是尚待解决的问题。目的比较分析CRVO黄斑水肿患者玻璃体腔内注射TA前后视网膜电图（ERG）的PhNR的变化,探讨PhNR作为治疗过程中监测视网膜功能的价值。方法收集比较CRVO伴黄斑水肿者12例13眼,于玻璃体腔内注射TA（0．1ml,4mg）前1d及注射后4周分别用标准小数视力表、光学相干断层扫描仪（OCT）、德国Roland RETI scan3．15系统检查视力、黄斑区视网膜厚度和PhNR。结果接受TA玻璃体腔注射后4周,12例患者13眼中有12眼视力提高,1眼视力不变。与玻璃体腔注射TA前比较,玻璃体腔注射TA后4周OCT显示黄斑区神经上皮细胞层水肿明显减轻,厚度减小;闪光视网膜电图（F—ERG）显示PhNR在玻璃体腔注射TA后波形明显改善。玻璃体腔注射前后患眼的视力分别为0．32±0．12和0．48±0．09,差异有统计学意义（t=6．325,P=0．000）;玻璃体腔注射后患眼黄斑区神经上皮层厚度与注射前比较明显下降[（459．46±131．31）μmvs（297．54±43．31）μm],差异有统计学意义（t=5．961,P=0．000）,玻璃体腔注射前后患眼的PhNR平均振幅值分别为（61．28±20．16）μV和（80．23±22．96）μV,差异有统计学意义（t=4．438,P=0．001）。玻璃体腔注射TA前后黄斑区神经上皮层厚度与PhNR振幅间均无明显的相关性（注射前：r=0．587,P=0．035;注射后：r=一0．011,P=0．971）。结论CRVO黄斑水肿患者行玻穗蚀日奉内沣射TA后,PhNR可以做为监测患者内层视网膜功能变化的有效指标。     

FD—OCT对原发性急性闭角型青光眼视网膜厚度和体积的测量

背景原发性急性闭角型青光眼（PAACG）大发作后可引起不同程度的视功能损害,了解PAACG发作眼视盘及黄斑区视网膜的结构改变对于判断患眼的预后具有重要的临床意义。傅里叶域OCT（FD-OCT）是测量视网膜结构的有用工具。目的采用FD—OCT对PAACG大发作后视盘区视网膜神经纤维层厚度（RNFLT）、黄斑区厚度以及黄斑区体积的变化进行测量,并与正常眼进行比较。方法采用病例对照临床试验方法。收集2011年4月至2012年2月在温州医学院眼视光医院确诊为PAACG且有一侧眼大发作的患者25例,并纳入同期年龄和性别相匹配的正常志愿者25人25眼为正常对照眼,于PAACG患眼大发作后2周由同一位操作熟练的检查者采用FD—OCT测量患者发作眼、对侧眼和正常对照眼RNFLT、黄斑区厚度及黄斑区体积。结果PAACG发作后2周内发作眼组视盘区平均RNFLT值为（125．72±28．57）μm,明显高于对侧眼组的（108．36±9．31）μm和正常对照眼组的（106．10±10．97）μm,差异均有统计学意义（P〈0．05）;此外,发作眼组视盘上方、下方、鼻侧象限RNFLT值均明显高于对侧眼组和正常对照眼组,差异均有统计学意义（P〈0．05）,而视盘颞侧象限和颞下象限RNFLT值的差异均无统计学意义（P=0．081、0．766）。发作眼组、对侧眼组和正常对照眼组黄斑区视网膜平均厚度分别（283．72±18．33）、（280．28±16．85）和（289．14±10．60）“m,3个组间黄斑区各象限视网膜厚度值差异无统计学意义（FH镕=2．048,P=0．136）,其中对侧眼组视网膜厚度值均明显低于正常对照眼组（P〈0．05）,发作眼组与正常对照眼组间差异无统计学意义（P=0．224）。发作眼组、对侧眼组和正常对照眼组黄斑区总体积分别为（5．589±O．355）、（5．532±0．325）和（5．720±0．241）mm。,黄斑区各象限体积比较差异无统计学意义（F＊。=1．027,P=0．363）。各组外环各象限厚度值均明显小于内环厚度值,内环及外环黄斑区视网膜厚度值均呈鼻侧〉上方〉下方〉颞侧的趋势。PAACG患者发作眼和对侧眼在视盘内环颞侧、上方、鼻侧、下方和外环颞侧、中央区黄斑区厚度值及其体积值均明显低于正常对照眼,差异均有统计学意义（P〈0．05）。结论PAACG发作眼发作2周内视盘区RNFL水肿比黄斑区更明显,发作眼和对侧眼的黄斑区视网膜均比正常对照眼变薄,其黄斑区体积均小于正常对照眼。     

相干光断层扫描观察鼠眼短暂缺血后的视网膜改变

目的 相干光断层扫描（OCT）观察鼠眼短暂缺血后的视网膜改变.方法 选取实验动物12只,随机作为鼠眼短暂缺血组和正常对照组（各6只）,行OCT检查以观察鼠眼短暂缺血与正常鼠眼的视网膜改变.结果 短暂缺血组的6只大鼠鼠眼均显示视网膜厚度增加,神经上皮层的反射性增强;OCT检查显示鼠眼短暂缺血组平均视网膜厚度为（205.50±9.95）.μm,正常鼠眼组为（186.17±3.49）μm,两者差异有统计学意义（t =4.489,P＜0.01）.结论 构建了鼠眼短暂缺血视网膜改变的实验模型,并由OCT观察改变情况,对今后利用动物进行相关研究具有重要意义.     

Comparison of the Diagnostic Ability of Retinal Nerve Fiber Layer Thickness Measured using Time Domain and Spectral Domain Optical Coherence Tomography in Primary Open Angle Glaucoma

 Purpose: To evaluate and compare the diagnostic ability of retinal nerve fiber layer (RNFL) thickness measurements using time domain (Stratus) and spectral domain (Cirrus HD) optical coherence tomography (OCT) in preperimetric and early primary open angle glaucoma (POAG). Methods: A total 62 eyes of 62 normal subjects, 47 eyes of 47 early perimetric damage POAG patients and 30 eyes of 30 preperimetric glaucoma patients were chosen in the study. All the subjects underwent peripapillary RNFL thickness measurements using Stratus OCT and Cirrus HD-OCT on the same day by a single trained operator. The RNFL thickness measured by Stratus OCT and Cirrus HD-OCT was statistically compared using paired t-tests. The relationship between RNFL thickness measured by two OCT instruments was evaluated using Pearson’s correlation coefficient. Areas under the receiver operating characteristic curves (AROC) were calculated and compared. Results: RNFL thickness measured using Stratus OCT was generally thicker than that using Cirrus HD-OCT(P＜0.05). A highly significant correlation between the two OCT instruments measurements was found in four quadrants and average RNFL thickness measurements (P＜0.001). The average RNFL thickness of Cirrus HD-OCT had significantly (P = 0.006) higher diagnostic ability (AROC = 0.951) than that of Stratus OCT (AROC = 0.881) in preperimetric glaucoma. There were no significant differences between the AROCs for other RNFL thickness parameters from Cirrus HD-OCT and Stratus OCT in preperimetric and early glaucoma (P＞0.05). Conclusion: Significant differences and an excellent correlation were noted in terms of RNFL thickness measurements using Stratus OCT and Cirrus HD-OCT. Cirrus HD-OCT presented higher diagnostic ability for preperimetric glaucoma.     

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.     

Comparability of retinal nerve fiber layer thickness measurements of optical coherence tomography instruments

PURPOSE: To compare retinal nerve fiber layer (RNFL) measurements between two ocular coherence tomography (OCT) instruments (OCT 2000 and Stratus OCT; Carl Zeiss Meditec, Dublin, CA) and compare their diagnostic precision. METHODS: One hundred thirty-nine consecutive subjects were imaged (3 x 3.4-mm diameter circular scans) on the same day with each instrument. Thirty-five patients were excluded due to poor-quality images. RNFL thicknesses measured by the two instruments were compared, and receiver operating characteristic (ROC) curves were used to determine diagnostic precision. RESULTS: A randomly selected eye of each of 104 participants (28 with open-angle glaucoma, 40 with suspected glaucoma, and 36 healthy subjects) was analyzed. RNFL thickness measurements generally were thicker with OCT 2000 than with Stratus OCT. The difference in global RNFL thickness between instruments was within 20 microm in 66 (65%) of subjects and within 10 microm (the instrument's limit of resolution) in 25 (25%) subjects. Application of a correction factor to OCT 2000 measurements predicted Stratus OCT RNFL thickness within 10 microm of the observed measurement in 75% of the eyes. For both instruments, highest ROC curve areas (better discrimination between glaucomatous and normal eyes) were found in the inferior sector. Discrimination using global RNFL thickness was better with Stratus OCT than OCT 2000 (P = 0.043). CONCLUSIONS: RNFL thickness measurements measured by OCT 2000 can be approximated to measurements made by Stratus OCT using correction factors calculated by this study. However, there remains considerable variability that exceeds the limits of resolution afforded by the instruments themselves. Therefore comparisons between instruments using these approximations should be interpreted with caution.     

Comparison of retinal nerve fiber layer thickness between Stratus and Spectralis OCT

Purpose

To compare the peripapillary retinal nerve fiber layer (RNFL) thickness of normal patients and those with various glaucoma diseases by time domain (Stratus) and spectral domain (Spectralis) optical coherence tomography (OCT).

Methods

The RNFL thickness as measured by the Stratus and Spectral OCT was compared (paired t-test). The relationship and agreement of RNFL thickness between the two OCT modalities were evaluated by Pearson correlation, Bland-Altman plot, and area under the receiver operating characteristic curve.

Results

Two-hundred seventeen eyes of 217 patients, including twenty-four normal eyes, ninety-one glaucoma suspects, seventy-six normal tension glaucoma cases, and twenty-six primary open angle glaucoma cases (POAG) were analyzed. The peripapillary RNFL thicknesses as measured by Stratus OCT were significantly greater than those measured by Spectralis OCT. However, in quadrant comparisons, the temporal RNFL thickness obtained using Stratus OCT were significantly less than those obtained using Spectralis OCT. Correlations between RNFL parameters were strong (Pearson correlation coefficient for mean RNFL thickness = 0.88); a high degree of correlation was found in the POAG group. Bland-Altman plotting demonstrated that agreement in the temporal quadrant was greater than any other quadrant.

Conclusions

Both OCT systems were highly correlated and demonstrated strong agreement. However, absolute measurements of peripapillary RNFL thickness differed between Stratus OCT and Spectralis OCT. Thus, measurements with these instruments should not be considered interchangeable. The temporal quadrant was the only sector where RNFL thickness as measured by Spectralis OCT was greater than by Stratus OCT; this demonstrated greater agreement than other sectors.     

Stratus OCT与GDxVCC测量正常人与青光眼患者视网膜神经纤维层厚度比较研究

目的 比较相干光断层扫描仪StratusOCT与激光偏振光视网膜扫描仪GDxVCC测量视网膜神经纤维层(RNFL)厚度的相关性及差异,探讨两者测量值与视野的相关性及其对青光眼的诊断效能.方法 84例原发性开角型青光眼(POAG)患者及50名正常人,随机选取一眼进行StratusOCT和GDxVCCRNFL厚度测量及Humphery自动视野计检查.相关分析比较两种仪器测量的全周、上方、下方RNFL厚度;回归分析研究视野的平均偏差与两种仪器测量的RNFL厚度值之间的关系;ROC曲线下面积分析两种仪器诊断青光眼的效能.结果 Stratus OCT测量正常人及POAG患者的全周RNFL厚度分别为(100.00±7.36)μm和(75.12±17.11)μm,GDxVCC对应测量值(57.16±5.05)μm和(48.00.4±8.46)μm.两种仪器测量的RNFL厚度呈线性相关(r>0.75).两种仪器测量的RNFL厚度值与视野的平均偏差呈正相关,三次曲线拟合度较直线相关的拟合度好.对于青光眼诊断,Stratus OCT的最大ROC曲线下面积为0.908,GDxVCC最大ROC曲线下面积为0.842.结论 Stratus OCT与GDxVCC测量RNFL厚度值存在差异,但两者呈线性相关,均与视野的平均偏差呈曲线相关.两种仪器诊断青光眼的效能均较好.     

屈光不正性弱视儿童黄斑中心凹和视神经纤维层厚度测量

目的:利用第三代光学相干断层扫描仪(3D-OCT)对屈光不正性弱视儿童患者黄斑中心凹及视神经纤维层厚度进行定量分析,比较其与正常儿童的差异。方法:选取于我院就诊的屈光正性弱视患者20例40眼,年龄4～10(平均6.15±1.64)岁,等效球镜1.50～7.00D,眼轴22.07±0.97mm;正常对照组25例50眼,年龄4～15(平均8.62±2.42)岁,等效球镜0.57±1.07D;眼轴22.81±0.72mm。利用第三代光学相干断层扫描仪(3D-OCT)分别对其黄斑中心凹和视神经纤维层厚度进行测量,所得数据应用SPSS13.0统计软件进行独立样本t检验、Pearson检验,比较其与正常对照组的差异。结果:弱视眼与正常眼黄斑中心凹厚度分别为132.98±14.99μm和136.60±13.82μm,比较无显著性差异(P>0.05);平均视神经纤维层厚度分别为116.95±9.59μm和110.40±7.63μm,比较有显著性差异(P<0.01);正常对照组平均视神经纤维层厚度与眼轴呈负相关(r=-0.31,P<0.05),弱视组平均视神经纤维层厚度与眼轴无明显相关性(r=0.12,P>0.05)。结论:屈光不正性弱视可能影响视神经纤维层厚度,但具体机制尚需进一步研究。     

Comparison of the influence of cataract and pupil size on retinal nerve fibre layer thickness measurements with time-domain and spectral-domain optical coherence tomography

Background: To investigate and compare the effect of cataract and pupil size on retinal nerve fibre layer (RNFL) thickness measurements using spectral‐domain optical coherence tomography (Cirrus OCT) and time‐domain OCT (Stratus OCT). Design: Prospective, hospital‐based study. Participants: Twenty‐five eyes from 25 normal subjects undergoing cataract surgery. Methods: Three retinal nerve fibre layer (RNFL) thickness measurements were taken before and after dilation, preoperatively and postoperatively, using Cirrus 200 × 200 Optic Disc Scan and Stratus Fast RNFL Scan. Main Outcome Measures: Linear regression, intraclass correlation coefficient (ICC) and coefficient of variation analysis. Results: Cataract removal caused significant increase in RNFL measurements in both modalities (Cirrus P < 0.02; Stratus P < 0.001). There was no significant difference in the increase in measurements between the two machines. Pupil dilation had variable and non‐statistically significant effect in both (P > 0.05). ICC showed excellent reproducibility with Cirrus OCT after mydriasis, preoperatively (ICC = 0.78–0.90) and postoperatively (ICC = 0.90–0.97), but poor reproducibility before mydriasis (P < 0.75). Stratus OCT achieved excellent reproducibility after cataract removal both before (ICC = 0.86–0.96) and after mydriasis (ICC = 0.92–0.95), but poor reproducibility before cataract surgery (P < 0.75). Conclusions: Cataracts, not pupil size, cause significant underestimation of RNFL measurements in both Cirrus and Stratus OCT. The extent of influence exerted does not appear different between the two instruments. Reproducibility of each machine appears to be affected differently. Mydriasis is required to achieve excellent reproducibility with Cirrus OCT, and media clarity is required with Stratus OCT.     

OCT检测青光眼视网膜神经纤维层局部缺损的临床研究

背景传统眼底照相的方法诊断视网膜神经纤维层（RNFL）局部缺损依赖于检查者的主观经验,而光学相干断层扫描（OCT）可以客观判断RNFL的局部缺损,新的频域OCT对RNFI,缺损的显示更直观。目的评价频域OCT、时域OCT对青光眼RNFL局部缺损的诊断价值及其与眼底彩色照相的一致性。方法由2位青光跟专家通过眼底彩色照相一致确认存在RNFL局部缺损的青光眼患者55例55眼和正常对照41名41眼纳入研究,分析眼底彩色照相、频域CirrusHD-OCT、时域Stratus OCT分别检测的RNFL局部缺损的位置和宽度,进行三者检测结果的一致性和相关性研究,评价OCT对RNFL局部缺损的诊断价值。结果确认青光眼患者55眼中共有RNFL局部缺损75处,分别位于颞上和颞下象限。CirrusHD-OCT和Stratus OCT检测RNFL损害的灵敏度分别是88．O％和69．3％,特异度分别是927％和97．6％。CirrusHD-OCT和Stratus OCT检测RNFL缺损的位置均与眼底彩色照相结果的检测值呈高度正相关（r=0．993、r=0．992,P〈0．01）;二者检测的RNFL缺损宽度与眼底彩色照相结果的检测值呈正相关（r=0．420、r=0．432,P=0．019、P=0．002）,CirrusHD-OCT和Stratus OCT检测RNFL缺损宽度与眼底彩色照相的检测值比较差异均无统计学意义（CirrusHD-OCT：P=0．114;Stratus OCT：P：0．074）。CirrusHD-OCT和Stratus-OCT检测RNFL缺损宽度值差异有统计学意义（P：0．002）。结论频域OCT和时域OCT均具有较好的诊断RNFL局部缺损的价值,与眼底彩色照相检测值有较好的一致性。     

Quantification of the retinal nerve fibre layer thickness in normal Indian eyes with optical coherence tomography

PURPOSE: To quantitatively assess the normative values for peripapillary retinal nerve fibre layer (RNFL) thickness with Optical Coherence Tomography (OCT 3) in Indian subjects. METHODS: The peripapillary retinal nerve fibre layer of 146 normal subjects was imaged on OCT 3 in this cross-sectional study. Thickness of the RNFL around the disc was determined with three 3.4 mm diameter circle OCT scan. The RNFL thickness was measured in four quadrants; superior, nasal, inferior and temporal. The data was analysed using SAS commercial statistical software. Influence of age and gender was evaluated on various measured parameters using unpaired t test, one-way analysis variance (ANOVA) and Pearson's correlation coefficient. RESULTS: One hundred and forty six eyes of 146 patients, 84 males and 62 females were studied. The average RNFL thickness in the sample population under study was 104.27 +/- 8.51 (95% CI 87.25-121). The RNFL was thickest in the inferior quadrant, followed by the superior quadrant, and progressively less in nasal and temporal quadrant. The difference between inferior and superior quadrants was not statistically significant. Age had a significant negative correlation with average RNFL thickness (r = -0.321, P = 0.000) and with average superior (r = -0.233, P = 0.005) and average inferior RNFL thickness (r = -0.234, P = 0.004). There was no effect of gender on various RNFL thickness parameters. CONCLUSIONS: RNFL thickness is significantly correlated with age, but not with gender. This normative database of RNFL thickness with OCT in Indian eyes is similar to previously reported values in normal Asian eyes.