Blood flow per unit retinal nerve fibre tissue volume is lower in the human inferior retina

AIM: To determine if perfusion per unit tissue volume of retinal nerve fibre layer and optic nerve head in the inferior sector is lower than in the superior sector. METHODS: Heidelberg retinal tomogram (HRT) for topographic measurement of optic nerve head and retinal nerve fibre layer and Heidelberg retinal flowmeter (HRF) for retinal blood flow were performed on 19 normal healthy subjects. Measurements from the superior and inferior sectors were compared. The perfusion/nerve fibre ratio (PNR); the blood flow per unit retinal nerve fibre tissue volume, was calculated in each sector with a formula; HRF flow measurements divided by HRT measurements. RESULTS: Retinal nerve fibre layer thickness in the inferior retina was significantly higher than in the superior retina (p<0.05). There were, however, no differences in retinal blood flow between the superior and inferior retinal sectors. The PNR in the inferior sector were significantly lower than in the superior sector (p=0.047 for HRF mean flow/rim volume and p = 0.0282 for HRF 75th percentile flow/rim volume). CONCLUSIONS: The inferior sector of retinal nerve fibre layer and optic nerve head may have lower blood flow per unit nerve tissue volume compared to the superior sector. This result suggests that the inferior sector is more vulnerable to elevated intraocular pressure (IOP) and ischaemic insults in glaucomatous optic neuropathy.     

应用海德堡视网膜断层扫描仪检测开角型青光眼的视盘改变

目的探讨海德堡视网膜断层扫描仪(Heidelberg retinal tomography,HRT)检测青光眼性视盘改变是否与视野损害的部位相一致,了解正常眼压性青光眼(normal tension glaucoma,NTG)与原发性开角型青光眼(primary open angle glaucoma,POAG)早或中期视盘形态是否异同.方法对64例(64只眼)仅有半侧视野异常的开角型青光眼(POAG27只眼、NTG37只眼)患者进行HRT检测,将Humphery视野与HRT的检测结果以0°～180°为界,分成上下两部分进行对应分析.结果与正常半侧视野对应的1/2视盘比较,显示异常半侧视野对应的1/2视盘HRT参数中,杯盘面积比、视杯形态测量值显著增大,而盘沿面积、视网膜神经纤维层厚度及视网膜神经纤维层横断面积值显著减少 (t=-2.625～3.025,P=0.003～0.05);NTG眼和POAG眼对应与异常半侧视野的HRT视盘参数差异无显著性(t=-0.98～1.511,P=0.14～0.97).结论 HRT参数能较准确反映与视野损害相一致的视盘变化,其中尤以杯盘面积比、盘沿面积、视杯形态测量、平均视网膜神经纤维厚度及视网膜神经纤维层横断面积测量值较为准确.NTG和POAG眼的视盘形态相似,可能具备某些相似的视神经损害发生机制.     

原发性开角型青光眼视盘及视网膜血流的研究

目的探讨原发性开角型青光眼患者和正常人视盘及其周边视网膜血液供应是否存在差异.方法本研究采用了一种新型共焦扫描激光多普勒血流仪--海德堡视网膜血流仪(heidelberg retina     

视网膜断层扫描仪在青光眼性视神经病变中的诊断价值

目的　评价视网膜断层扫描仪在青光眼性视神经病变中的诊断价值。方法　应用海德堡视网膜断层扫描仪 (HRT)检测 116例 (116只眼 )正常人和 6 3例 (99只眼 )原发性开角型青光眼(POAG)患者的视乳头地形图参数 ,比较两者间各参数的差异 ;将正常人与POAG患者的视乳头地形图参数进行逐步判别分析 ,建立判别函数 ,筛选出诊断POAG的敏感参数并进行回代分析。结果POAG患者的视盘面积 (DA)、视杯面积 (CA)、杯 /盘面积 (C/DAR)、盘沿面积 (RA)、视乳头轮廓线高度变化值 (HVC)、视杯容积 (CV)、盘沿容积 (RV)、平均视杯深度 (MCD)、最大视杯深度 (MxCD)、视杯形态测量 (CSM)、平均视网膜神经纤维层厚度 (mRNFLT)、视网膜神经纤维层截面面积 (RNFLA)与正常人比较差异有显著意义 (P <0 0 0 1) ;对POAG诊断敏感的视盘地形图参数为C/DAR、RA、CSM、CV和MxCD ;判别函数式为Y =- 2 0 83- 4 833×C/DAR - 2 0 379×CSM 2 0 35×RA 3 95 5×CV - 3 70 1×MxCD ;对POAG诊断的敏感性、特异性及诊断符合率分别为 81 8%、86 2 %及 84 2 % ,与HRT自动分析程序相当。结论　POAG患者视乳头地形图与正常人差异较大 ;利用我国人的数据资料建立的判别函数对POAG诊断效能与HRT自动分析程序相当 ,说明HRT自动分析程序在一定程     

A comparison of optic disc topographic parameters in patients with primary open angle glaucoma,normal tension glaucoma,and ocular hypertension

Background Heidelberg Retina Tomograph (HRT) findings have been employed to quantitatively assess the topography of optic discs. We measured topographic parameters of optic discs in patients with primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), and ocular hypertension (OH) using an HRT in order to determine whether HRT topographic parameters can be used to differentiate those conditions.Methods Seventeen eyes in 17 patients with POAG, 23 eyes in 23 patients with NTG, and 15 eyes in 15 patients with OH were examined using an HRT, and the results were analyzed by age, refractive error, and topographic parameters.Results Among the HRT parameters, the mean values for rim area, rim volume, cup disk area ratio, and classification showed significant differences among POAG, NTG, and OH eyes. The mean values for cup area, cup volume, mean RNFL thickness, and RNFL cross section area showed significant differences between POAG and NTG eyes, and NTG and OH eyes, however, not between POAG and OH eyes. Cup shape measure showed significant differences between POAG and OH, and NTG and OH eyes, but not between POAG and NTG eyes.Conclusions Our results suggest that POAG is distinguishable from NTG and OH based on evaluations of rim area and rim volume. Patients with NTG tend to have larger cupping, smaller rims, and thinner retinal nerve fiber layers as compared to POAG and OH patients. Thus, HRT topographic parameters are useful to differentiate patients with POAG, NTG, and OH.     

Papillary blood flow and morphological parameters of the optic nerve head in patients with normal tension glaucoma, primary open angle glaucoma and in healthy volunteers

The aim of the present study was to compare selected morphological parameters of the optic nerve head and papillary blood flow in patients with NTG, POAG and in healthy volunteers, as well as to find any possible correlation between selected morphological parameters and papillary blood flow. 21 glaucomatous and 31 normal eyes were diagnosed using HRT and HRF. Statistically significant differences within many morphological parameters like cup area, cup to disc, cup shape measure, rim volume, RFNL thickness, RFNL cross section and neuroretinal rim blood flow appeared. Nevertheless, in glaucoma patients no statistically significant differences between morphology and flow were found. The conclusion is that blood flow impairment within the neuroretinal rim is connected with glaucoma neuropathy development, nevertheless it is affected by other factors.     

海德堡视网膜断层扫描仪测量正常人视盘参数

目的 :建立正常人群海德堡视网膜断层扫描仪 (Heidelbergretinatomograph ,HRT)视盘参数的正常值 ,明确哪些因素对正常人HRT视盘参数有影响。方法 :选用 10 2例 (13 2只眼 )正常人 ,用HRT进行视盘扫描 ,视盘参数包括视盘面积、视杯面积和容积、盘沿面积和容积、视杯形态、视杯平均深度和最大深度、杯 /盘面积比、沿 /盘面积比、平均视网膜神经纤维层(retinalnervefiberlayer,RNFL)厚度和横截面积、水平C/D和垂直C/D。计算正常人视盘参数范围 ,用直线回归的方法判断视盘大小和年龄对视盘参数的影响。结果 :正常人左右眼和男女间视盘各参数差异无显著意义 (P >0 0 5)。年龄与RNFL厚度及横截面积呈负相关 ,相关系数分别为 -0 2 3 4和 -0 2 3 5,其余各参数与年龄无关。盘沿容积和视杯最大深度不受视盘大小的影响 ,其余各参数均与视盘大小呈线性相关。结论 :HRT可定量检测正常人视盘参数 ;正常人视盘参数变异很大 ,盘沿容积不受视盘大小的影响 ,是一个区分正常与早期青光眼的很好的参数     

高眼压性和正常眼压性原发性开角型青光眼视神经损害特征的比较

目的探讨高眼压性原发性开角型青光眼(POAG)和正常眼压性青光眼(NTG)患者视神经损害的不同特点。方法应用德国Heidelberg公司生产的视网膜断层扫描仪对高眼压性POAG39例(47只眼)和NTG32例(38只眼)进行定量视盘参数和神经纤维层检查,并行眼底立体照相观察视网膜神经纤维层(RNFL)缺损类型,检测静态定量视野,并对检查结果进行比较。结果(1)NTG组视盘总体参数和分区(除颞侧外)盘沿面积、沿/盘面积小于高眼压性POAG组,而C/D大于高眼压性POAG组;平均RNFL厚度和RNFL面积在颞下和颞上小于高眼压性POAG组;总体盘沿容积小于高眼压性POAG组,总体平均视杯深度和颞下视杯面积大于高眼压性POAG组,两组差异均有统计学意义(P<005)。两组颞侧视盘各参数比较,差异无统计学意义(P>005)。(2)RNFL缺损类型高眼压性POAG组RNFL弥漫性缺损占5319%,局限性缺损占426%;NTG组弥漫性缺损占2105%,局限性缺损占5526%。两组RNFL缺损类型构成比比较,差异有统计学意义(P<001)。结论NTG较高眼压性POAG具有较大的C/D值、C/D面积比和窄盘沿面积,RNFL丢失严重。高眼压性POAG患者的RNFL以弥漫性缺损为主,NTG患者的RNFL以局限性缺损为主。两者视神经损害具有不同特点,其损害机制可能不同。(中华眼科杂志,2005,41136140)     

用Heidelberg视网膜断层扫描仪对正常人、大杯和青光眼视乳头形态结构的研究

目的：探讨正常人、大杯和原发性开角型青光眼（ｐｒｉｎａｒｙ ｏｐｅｎ ａｎｇｌｅ ｇｌａｕｃｏｍａ,ＰＯＡＧ）患者之间视乳头结构参数之间的差异。方法：用Ｈｅｉｄｅｌｂｅｒｇ视网膜断层扫描仪（Ｈｅｉｄｅｌｂｅｒｇ Ｒｅｔｉｎａ Ｔｏｍｏｇｒａｐｈ,ＨＲＴ）对正常人（２２例４４眼）、大杯（１７例３４眼）和ＰＯＡＧ患者（１９例３７眼）进行视乳头断层扫描,获得视乳头平均地形图图像和视乳头结构诸参数。结果：     

HRT视盘参数在原发性开角型青光眼早期诊断中的作用

目的:在众多海德堡视网膜断层扫描仪(heidelberg retina tomogragh,HRT)测定的视盘参数中,筛选出最有助于青光眼早期诊断的视盘参数。方法:用HRT测定23例视野损害较轻的青光眼患者和23例正常人的视盘参数(杯盘面积比、盘沿面积、盘沿容积、视杯容积、视杯形态测量、视杯高度变异轮廓和平均神经纤维层厚度)作逐步判别分析。结果:盘沿面积和杯盘面积比对青光眼早期诊断最有帮助,其诊断敏感度和特异度分别为87%和96%。结论:本组资料盘沿面积和杯盘面积比是区分青光眼和正常眼最好的判别因素。     

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。     

Topography and fluorescein angiography of the optic nerve head in primary open-angle and chronic primary angle closure glaucoma.

PURPOSE: The purpose of this study is to correlate optic nerve head topography with fluorescein angiography of the optic nerve head in patients with primary open-angle glaucoma (POAG), chronic primary angle closure glaucoma (CPACG), and normal controls. METHODS: This was an institution-based, cross-sectional, case-control study of 30 consecutive patients each with POAG or CPACG, which were compared with 30 age- and sex-matched controls. The fluorescein angiograms undertaken in one eye of each of the 90 subjects were then analyzed both qualitatively and quantitatively. RESULTS: The mean age of controls (group 1) was 51.73 +/- 9.6 years, patients with CPACG (group II) was 53.26 +/- 9.5 years, and patients with POAG (group III) was 54.5 +/- 10.4 years. The mean deviation and corrected pattern standard deviation on Humphrey visual field analyzer, respectively, were -1.51 +/- 2.01 dB and 2.09 +/- 1.04 dB the in control group, -9.4 +/- 9.3 dB and 5.32 +/- 4.02 dB in the CPACG group, and -11.27 +/- 7.7 dB and 7.57 +/- 5.34 dB in the POAG group. There was no significant difference in the disc areas between the three groups (analysis of variance [ANOVA], p = 0.157). All circulatory parameters were delayed in both glaucoma groups compared with controls with the disc filling time (ANOVA, p = 0.001) and the choroidal filling time being significantly delayed (ANOVA, p = 0.006). The Moorfield regression analysis showed good correlation with the pattern of disc fluorescence in all quadrants in cases of CPACG and POAG. CONCLUSION: The optic nerve head and choroidal circulation was delayed in both patients with POAG and those with CPACG, which correlates with loss of neuroretinal rim and retinal nerve fiber layer on the Heidelberg Retina Tomograph II (HRT). Patients with POAG showed diffuse damage with significant rim loss, whereas patients with CPACG showed marked sectorial abnormalities (superotemporal and the inferior-temporal) on fluorescein angiography and HRT. One possible reason for this discrepancy could be sectorial ischemia occurring in cases of CPACG as a result of a sudden rise of intraocular pressure causing disc and visual field damage.     

Optic nerve head topographic measurements and retinal nerve fiber layer thickness in physiologic large cups

PURPOSE: To evaluate the parameters of optic nerve head (ONH) and retinal nerve fiber layer (RNFL) in patients with large cup/disc ratio (CDR) and normal neuroretinal rim configuration who have normal perimetry (physiologic large cups, LC) and to compare these parameters with those of the normal and early glaucoma patients. METHODS: Using Heidelberg retinal tomography (HRT) and optical coherence tomography (OCT), 30 patients with LC, 29 normal subjects, and 31 early glaucoma patients were examined. One eye from each subject was randomly selected. RESULTS: Significant differences between LC and glaucomatous eyes (GE) were found in parameters indicating loss of nerve fibers, such as rim area, rim volume, and mean RNFL thickness. However, there was no difference between LC and normal eyes (NE) in RNFL thickness, rim area, and rim volume. LC was able to be defined as a normal central excavation with a large disc and large CDR with a normal rim area. CONCLUSIONS: HRT ONH parameters and RNFL thickness obtained with OCT may be useful for differentiating between glaucoma and LC eyes.     

Optic disc topography as measured by confocal scanning laser ophthalmoscopy and visual field loss in Japanese patients with primary open-angle or normal-tension glaucoma

PURPOSE: To determine whether differences in the optic disc topography and those in the relation between the optic disc topography and visual field indices exist between Japanese patients with primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG). METHODS: The study included consecutive Japanese patients with POAG (n = 60) or NTG (n = 60). Using the Heidelberg Retina Tomograph (HRT), we measured disc area, cup area, cup-to-disc area ratio, rim area, cup volume, rim volume, cup shape measure, and height variation contour. Each HRT parameter was measured in the total optic disc and in its four 90 degree quadrants (superior, temporal, inferior, and nasal). The mean deviation for the entire field and the sum of the total deviation values corresponding to each optic disc quadrant were calculated using the Humphrey full-threshold 30-2 program. RESULTS: No significant differences were found between the POAG and NTG groups for any HRT parameter either globally or regionally. There were no significant differences between the two groups in the correlation coefficients between any HRT parameter and the corresponding visual field indices either globally or regionally. CONCLUSION: No significant differences were apparent between Japanese patients with POAG and NTG both in the optic disc parameters as measured by HRT and in the degree of correlation between HRT parameter and the corresponding visual field indices.     

Comparison of optic nerve head between normal and glaucoma subjects with Heidelberg Retina Topograph: to introduce a new diagnostic pattern]

PURPOSE: To compare the differences of optic disc topograph between normal and glaucomatous persons, and to establish the score classification pattern for glaucoma using Heidelberg Retina Topograph (HRT). METHODS: One hundred and sixteen eyes from 116 normal controls, 99 eyes from 63 consecutive primary open angle glaucoma(POAG) patients, and 75 eyes from 42 patients with POAG in early stage were included. All subjects underwent HRT exams. The topograph parameters of optic nerve head obtained from HRT were compared between normal and glaucoma, according to the 50%,95%,and 99% distribution of each parameter defining as score -4, -3, -2, -1, 1, 2, 3, 4. The total value of all parameters in one eye were calculated as a diagnostic index. And the cut-off points were determined by specificity of 95% for certain glaucoma and certain normal, the others were classified into suspects. RESULTS: The differences of optic disc topograph between normals and glaucomatous patients were significant. When consecutive glaucoma data were analyzed by the new score classification pattern, miss-diagnosis ratio was 6.1%, mis-diagnosis was 5.2%, correctly diagnostic ratio was 57.6%, suspects ratio was 36.4%. When POAG in early stage data were analyzed, the miss-diagnosis ratio and mis-diagnosis ratio were 5.2%, 5.2%, respectively; correctly diagnosis ratio is 36%, suspects ratio is 53.3%. CONCLUSIONS: The differences of optic nerve head topograph between normals and glaucomatous patients are significant. The new diagnostic pattern which will classify subjects into normals, suspects, and glaucoma, may be useful to lower miss-and misdiagnosis rate clinically.     

Optic disc blood flow measured by scanning laser-Doppler flowmetry using a new analysis program

PURPOSE: Using a new analysis program for scanning laser-Doppler flowmetry (SLDF) by a Heidelberg retina flowmeter (HRF), we studied the relation between flow and visual field or disc morphology. SUBJECTS AND METHODS: In 42 eyes of 21 patients with normal tension glaucoma (NTG) the mean-flow of the HRF blood flow parameters at the disc rim was measured and analyzed by a new analysis program for perfusion maps (the SLDF analysis tool), to minimize the influence of large vessels or/and artifacts caused by small eye movements. We investigated whether difference of the mean-flow between a pair of eyes had any relation to differences between a pair of eyes in visual field indices and those in disc morphological measurements of the Heidelberg retina tomograph. RESULTS: We found statistically significant correlations between the mean-flow and optic disc parameters (Disk Area, Cup Area, Height Variation Contour, Cup Volume, Rim Volume, Mean RNFL Thickness). We found no statistically significant correlations between the mean-flow and visual field parameters (mean deviation, corrected pattern standard deviation). CONCLUSION: The results suggested that eyes with less flow in the optic disc rim have more advanced glaucomatous morphological changes.     

Relationship between blood flow velocities in retrobulbar vessels and laser Doppler flowmetry at the optic disk in glaucoma patients

The relationship between blood flow velocities in retrobulbar vessels and blood flow at the optic nerve in glaucoma patients was assessed in a prospective study. The Heidelberg retina flowmeter (HRF) was used to assess optic nerve head blood flow in 13 open-angle glaucoma patients. In the same patients, color Doppler imaging (CDI) measurements were obtained from the ophthalmic artery, the central retinal artery and the posterior ciliary arteries. Using data for one randomly selected eye per subject, correlations between HRF recordings and CDI measurements were evaluated by means of Spearman's rank correlation factor. All three HRF parameters correlated with CDI measurements obtained from retrobulbar vessels. The most marked correlations were those of the HRF parameter 'volume' with the end-diastolic velocity in the ophthalmic artery and the medial posterior ciliary artery (R = 0.79, p = 0.0012 and R = 0.81, p = 0.0007, respectively), and the peak systolic velocity in the lateral posterior ciliary artery (R = 0.82, p = 0.0006). The present study suggests that glaucoma patients with altered blood flow in retrobulbar vessels are likely to show an alteration in optic nerve blood flow as measured with the HRF.     

Optic Disc Blood Flow Measured by Scanning Laser-Doppler Flowmetry Using a New Analysis Program

Purpose: Using a new analysis program for scanning laser-Doppler flowmetry (SLDF) by a Heidelberg retina flowmeter (HRF), we studied the relation between flow and visual field or disc morphology.Subjects and Methods: In 42 eyes of 21 patients with normal tension glaucoma (NTG) the mean-flow of the HRF blood flow parameters at the disc rim was measured and analyzed by a new analysis program for perfusion maps (the SLDF analysis tool), to minimize the influence of large vessels or/and artifacts caused by small eye movements. We investigated whether difference of the mean-flow between a pair of eyes had any relation to differences between a pair of eyes in visual field indices and those in disc morphological measurements of the Heidelberg retina tomograph.Results: We found statistically significant correlations between the mean-flow and optic disc parameters (Disk Area, Cup Area, Height Variation Contour, Cup Volume, Rim Volume, Mean RNFL Thickness). We found no statistically significant correlations between the mean-flow and visual field parameters (mean deviation, corrected pattern standard deviation).Conclusion: The results suggested that eyes with less flow in the optic disc rim have more advanced glaucomatous morphological changes.     

Relationship between optic nerve head microcirculation and visual field loss in glaucoma

PURPOSE: To study the relationship between optic nerve head blood flow velocity and visual field loss in patients with primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG). METHODS: This study included 44 eyes of 44 patients with POAG and 44 eyes of 44 patients with NTG. To evaluate optic nerve head blood flow velocity, the square blur rate (SBR) was measured by means of laser speckle flowgraphy. The correlation between SBR and Humphrey visual field indices was evaluated with linear regression analysis. RESULTS: In the NTG group, the average SBR at the superior and inferior temporal neuroretinal rim was positively correlated with mean deviation (MD) (r = 0.349, p = 0.020). The SBR at the superior or inferior temporal neuroretinal rim was positively correlated with the sum of the total deviations in the corresponding hemifields (r = 0.299, p = 0.049; r = 0.354, p = 0.019, respectively). The correlations between SBR and MD did not differ statistically between the NTG and POAG groups; however, no significant correlation between SBR and visual field indices was observed in the POAG group. CONCLUSION: These results suggested that the change in the circulation of the optic nerve head may be related to visual field damage in the NTG group but may be less involved in visual field damage in the POAG group.     

海德堡视网膜断层扫描仪检测青光眼患者视乳头地形图参数的一致性研究

目的 评价不同观察者间和同一观察者不同时间对视乳头地形图参数分析的一致性。方法 应用海德堡视网膜断层扫描仪(HRT)检测14例(24只眼)正常人和16例(26只眼)原发性开角型青光眼患者的视乳头地形图,再由3位青光眼专业医师分别独立描画受检者的视乳头边界轮廓线,其中1位医师于不同时间分别描画3次。用HRT软件(2．01版本)对11个视乳头地形图参数(视乳头面积、视杯面积、视杯／视盘面积、盘沿面积、视杯容积、盘沿容积、平均视杯深度、最大视杯深度、视杯形态测量、平均视网膜神经纤维厚度、视网膜神经纤维层截面面积)进行分析,并分别计算类内相关系数(ICC值)和结果判断一致性(kappa值)。结果 3位不同观察者间检测患者视乳头地形图的各参数基本一致,ICC值为0．976～0．999,kappa值为0．649～0．767,显示三者间检测结果的一致性较好;同一观察者不同时间检测的视乳头地形图各参数基本一致,ICC值为0．983～0．999,kappa值为0．810～0．951,显示同一观察者不同时间检测结果的一致性较好。结论 在具有一定经验的观察者间和同一观察者不同时间,对HRT图像视乳头轮廓线描画的一致性均较好,该方法可用于青光眼的临床诊断和追踪观察。