A Study on the Structure of Human Optic Nerve Lamina Cribrosa

Purpose:To determine the mechanism of nerve fiber damage in glaucoma by studing the structure of hu-man optic nerve lamina cribrosa(LC)in different regions.Methods:15 human eyes of 10cases were stuided.The specimens were prepared for scanning electron microscopy,and numbers and areas of pores in LC were measured by electron image analysis system.Draw a frequency distribution map with each curve represents the tendency of pores distribution in a particular part.The proportion of the connective tissue in respective quadrant can also be calcu-lated.The specimens were also prepared for histological examination.Results:There are many pores of various magnitude and shapes on the surface of LC.There are significantly more large pores(≥3000μm^2)in the superior and in-ferior than those in the nasal and temporal quadrants,especially in the peripheral regions,In terms of area,the percentages of connective tissue in the nasal and temporal quadrants are the highest.Collageous fibers,various in diameter,are arranged in bundles and tangentially around each pore.Conclusion:In normal persons,the percentage of large pores in the superior and inferior peripheral parts is the highest,the density of the connective tissue is the lowest.So,the force received by unit area of the superior and inferior parts is bigger than that of the nasal and temporal sides.therefore,it is susceptible to the impact of high intraocular pressure at the early stage and causing correspond-ing visual edfect.Our study may suggest the mechanism of optic nerve damage of glaucoma,Eye Science 1995;11:147-154.     

Characteristics of Reversal Optic Cupping in Adults Glaucoma after Reduction of Intraocular Pressure

Purpose:According to Quigley‘s hypothesis the dense of connective tissue is the least and the pores of the lamina cribrosa are the largest at the superior and infe-rior poles of the lamina cribrosa,therefore they are the most vulnerable location to be involved in the characteristic glaucomatous optic nerve damage,To get clin-ical evidence for the hypltheses,the reversal of optic cup in adults glaucoma after reduction of intraocular pressure(IOP)was examined.Methods:The stereoscopic flicker comparison on with computerized image sys-tem was used to monitor the optic cup‘s changing,2 serial superposed stereo pairs were displayed alternatively and rapidly and the changing parts appeared moving Under the stereoscopic observation ,hthe changes of 3-dimention optic cup could be seen and the false positive phenomena caused by photographic angle variation,vascular pulsation could be differentiated from the characteristic change of the cup.Stereo fundus photographs were taken from 31eyes with hy-pertension glaucoma before and after treatment of reduction of IOPs which was either diamox administration or trabeculectomy.Results:the result showed that the reversal of optic cups after reduction of IOPs were mostly asymmetrical,especially at the inferior and/or superior poles.By multiple stepwise regression.it is known that the amount of the change is only correlated with the initial elevated IOP.Conclusions:The study indicated that it was the distortion and deformity of the lamina cribrosa leading to shearing stress that results in glaucomatous character-istic damage in structure and function.The individul tolerance of the lamina cribrosa to the high intraocular pressure and the locations of indivdual vulnerable at he optic nerve head are various.Eye Science1995;11:155-160.     

Effect of High Dosage of Methylprednisolone on Rat Retinal Ganglion Cell Apoptosis after Optic Nerve Crush

Traumaticopticneuropathyisanuncommonbutoftendevastatingcauseofpermanentvisuallossafterbluntorpenetratinginjury.Opticnerveiscomposedoftheaxonsofretinalganglioncells(RGC).Opticnerveaxotomycausedrapiddegenerationoftheaxonsandmorethan90%oftheRGCdiedbyapoptosiswithin2weeks[1].AttemptsweremadetopreservetheinjuriedRGCbychangingtheenvironmentorbyupregulatingintrinsicgrowthfactorssurroundingtheRGC[2].Apoptosisisaregulatedprocessunderthecontrolofproteins.TheBcl鄄2genefamilyisoneofthemostimportanta…     

The Comparison Study of Renin and Angiotensin A Ⅱ Levels on Normal Tension GlaucomaPatients and Normal Individuals

PURPOSE: To investigate the levels of renin-angiotension system (RAS) components in normal tension glaucoma patients and normal controls. METHODS: Blood samples were obtained from 11 normal tension glaucoma(NTG)patients and 11 age and sex matched controls. The levels of renin and angiotensin A II of 11 NTG patients and normal controls were examined by radio-immunity test. Statistical analyses were performed by paired t test. RESULTS: The levels of renin of NTG patients and normal controls are (769.085+/-183.217) pg/ml/n and (822.035+/-124.140) pg/ml/n, while the levels of angiotensin A II of NTG patients and normal controls are (37.347+/-10.669) pg/ml and (24.836+/-10.665) pg/ml respectively. No statistically significant differences were observed between the levels of renin and angiotensin among NTG patients and normal controls. CONCLUSION: There were not many abnormalities of the levels of circulating rennin and angiotensin A II of NTG patients in our study.     

原发性开角型青光眼共焦扫描激光多普勒视网膜血流图

目的:探讨原发性开角型青光眼血流动力学障碍机制.方法:应用共焦扫描激光多普勒视网膜血流图对91例173眼原发性开角型青光眼的视乳头和视网膜的血流进行了检测.结果:视乳头平均血容量、流量和红细胞移动速率分别是105.47±47.42,3231.07±1486.06,8.39±2.82;筛板处平均血容量、流量和红细胞移动速率分别是7.88±4.64,122.17±84.07,0.44±0.28;盘沿处平均血容量、流量和红细胞移动速率分别是18.48±14.20,478.18±437.88,1.56±1.17;盘缘外视网膜平均血容量、流量和红细胞移动速率分别是14.15±6.04,268.48±138.50,0.95±0.46;视网膜平均血容量、流量和红细胞移动速率分别是18.09±6.56,352.45±189.63,1.24±0.60;血管、筛板和视网膜的血容量、流速和红细胞移动速率和正常眼比较都有明显下降.结论:原发性开角型青光眼存在着血流动力学障碍.     

Spatio—temporate Expression of P53,Bcl—2 and Fas in the Retina of RD,a

Purpose: To investigate the expression status of p53, Fas and bcl-2 in the developmentof retinal degeneration in C3H, rd and rds mice.Methods: Expression of p53, Fas and bcl-2 in the retina of rd,rds and C3H mice as wellas in normal C3B mice in different periods was examined by immunohistochemicaltechnique.Results: The expression of Fas and p53 was not detected in normal C3B mice. Fas andp53 were expressed in the ganglionic layer in the early stage and then in the innernuclear layer, while the scale and intense increased in the ganglionic layer. There is nodifference of bcl-2 expression between the normal mice and mice with retinaldegeneration.Conclusion: Fas and p53 may be involved in the retinal cell death in rd, rds, and C3B,but bcl-2 may not. It is unknown why p53 and Fas appeared first in ganglion layer butnot in the outer nuclear layer where retinal cells death was noticed in early stage. EyeScience 2000; 16: 158 ~ 162.     

The Study of Influencing Factors on the Growth Characters of Sprague—Dawley Rat Retinal Neurons in Vitro

Purpose: To investigate the influencing factors in culturing Sprague-Dawley (S-D) rats retinal neurons in order to lay foundation for further experimental research. Materials and Methods: Retinal cells were plated on plastic plates and coverslips coated with poly-1-lysine or ethylene imine polymer for primary culture. The cultured cells were divided into following groups: 1. Culture medium changed every 2 to 3 days vs changed only once; 2. Cytosine arabinoside (Ara-C) added to the culture medium vs not added. The cells were observed and pictured under inverted phase contrast microscope. The cells were identified through immunocytochemistry.Results: The immunofluorescence showed that most of the cultured cells were neurons, among them were a few retinal ganglion cells. In the cultured group of which substrata coated with poly-1-lysine and culture medium added with Ara-c, the neurons intended to aggregate into clusters with relatively straight neurites . In the group of which substrata coated with ethylen     

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：     

Variability of Heidelberg Retina Tomograph parameters during exercise

Purpose: The purpose of this study was to determine whether exercise affects the stereometric parameters representing optic nerve head (ONH) topography. Methods: ONH topography, intraocular pressure (IOP) and blood pressure of 30 healthy volunteers were monitored before, during and after dynamic exercise raising systolic blood pressure by a minimum of 30 mmHg. Change in the stereometric ONH parameters was calculated. Results: IOP decreased and blood pressure increased during exercise, resulting in an increase in mean ocular perfusion pressure. Exercise was associated with an increase in variance in 17 of the 18 stereometric ONH parameters. The increase in variance was statistically significant in eight parameters, including rim area, cup/disc area ratio and cup shape measure. There was no statistically significant change in image quality. The absolute change from baseline in rim area, cup area, cup/disc area ratio, rim/disc area ratio and rim volume showed a statistically significant (p < 0.05) correlation with change in mean ocular perfusion pressure. Conclusions: Exercise increases variability in stereometric ONH parameters. To avoid increased variance in the stereometric parameters, ONH imaging should be performed after allowing sufficient time to rest.     

Factors affecting the sensitivity and specificity of the Heidelberg Retina Tomograph parameters to glaucomatous progression in disc photographs

Purpose: To evaluate the factors affecting the sensitivity and specificity of the stereometric optic nerve head (ONH) parameters of the Heidelberg Retina Tomograph (HRT) to glaucomatous progression in stereoscopic ONH photographs. Methods: The factors affecting the sensitivity and specificity of the vertical cup : disc ratio, the cup : disc area ratio, the cup volume, the rim area and a linear discriminant function to progression were analysed. These parameters were the best indicators of progression in a retrospective study of 476 eyes. The reference standard for progression was the masked evaluation of stereoscopic ONH photographs. Results: The factors having the most significant effect on the sensitivity and specificity of the stereometric ONH parameters were the reference height difference and the mean topography standard deviation (TSD), indicating image quality. Also, the change in the TSD and age showed consistent, but variably significant, influence on all parameters tested. The sensitivity and specificity improved when there was little change in the reference height, the image quality was good and stable, and the patients were younger. The sensitivity and specificity of the vertical cup : disc ratio was improved by a large disc area and high baseline cup : disc area ratio. The rim area showed a better sensitivity and specificity for progression with a small disc area and low baseline cup : disc area ratio. Conclusion: The factors affecting the sensitivity and specificity of the stereometric ONH parameters to glaucomatous progression in disc photographs are essentially the same as those affecting the measurement variability of the HRT.     

用Heidelberg视网膜断层扫描仪对正常眼压性青光眼与正常人视盘形态结构的对比研究

目的 比较正常人(本文所指正常人指非青光眼者)和正常眼压性青光眼(Normal Tension Glaucoma，NTG)视盘形态结构参数之间的差异，以指导正常眼压青光眼的早期诊断。方法 用Heidelberg视网膜断层扫描仪(Heidelberg Retina Tomograph Ⅱ，HRTⅡ)对正常人40例(80眼)及NTG30例(60眼)的视乳头进行断层扫描，获得视乳头平均地形图像和视乳头结构诸参数。结果 正常人与NTG视乳头结构各参数中视盘面积、视杯面积、杯盘比、盘沿面积、视杯容积、平均视杯深度、最大视杯深度、平均视神经纤维层厚度及视神经纤维层横截面积存在明显差异。结论 HRT能在活体对视乳头结构进行准确分析，视盘面积可能是青光眼的一个易感因素，对NTG早期诊断具有帮助。     

Comparison of optic nerve head parameters using Heidelberg Retina Tomograph 3 and spectral-domain optical coherence tomography

Background: To assess the agreement between the Heidelberg Retina Tomograph and Cirrus spectral‐domain optical coherence tomography (Cirrus HD‐OCT [Carl Zeiss Meditec, Dublin, CA, USA]) when measuring optic disc parameters. Design: Prospective, cross‐sectional study. Participants: A total of 96 glaucoma patients and 21 normal subjects were analysed. Methods: Optic nerve head measurements, including disc area, rim area, cup‐to‐disc ratio and cup volume were obtained using both the Cirrus HD‐OCT and Heidelberg Retina Tomograph 3 (Heidelberg Engineering GmbH, Heidelberg, Germany). Main Outcome Measurements: Bland–Altman plots were used to evaluate the agreement between each of the optic disc parameters. Results: Although Cirrus HD‐OCT values were smaller than Heidelberg Retina Tomograph 3 values for the disc and rim areas, overall the Cirrus HD‐OCT and Heidelberg Retina Tomograph 3 measurements were highly correlated (r = 0.657 to 0.821). As compared with Heidelberg Retina Tomograph 3, disc and rim areas tended to be minimized by Cirrus HD‐OCT, especially when there were large disc and rim areas, although there was no relationship between the discrepancy and the level of measurement of the cup‐to‐disc ratio. The optical coherence tomography overestimated the Heidelberg Retina Tomograph‐determined cup volume, especially when there were large cup volumes. Conclusions: Bland–Altman analyses revealed that with the exception of the cup‐to‐disc ratio, there was poor agreement between the Cirrus HD‐OCT and Heidelberg Retina Tomograph 3 morphometric measurements. In addition, with the exception of the cup‐to‐disc ratio, the optic nerve head measurements could not be directly compared between the Cirrus HD‐OCT and Heidelberg Retina Tomograph 3.     

Heidelberg Retina Tomograph (HRT3) in Population-based Epidemiology: Normative Values and Criteria for Glaucomatous Optic Neuropathy

Purpose: To establish normative values for Heidelberg Retina Tomograph (HRT3) variables and to develop HRT3-based criteria for glaucomatous optic neuropathy for epidemiological research in a white population.

Methods: Consecutive participants in the Rotterdam Study were examined with HRT and simultaneous stereoscopic fundus photography (ImageNet) in addition to other ophthalmic examinations including intraocular pressure (IOP) measurements and perimetry. Normative values for all HRT3 variables were determined in participants who met all the following criteria: no glaucomatous visual field loss (GVFL), an IOP of 21mmHg or less, no IOP lowering treatment, and a negative family history of glaucoma. Sensitivity was determined in participants with glaucomatous visual field loss at a fixed high specificity of 97.5% ? a value commonly used in population-based epidemiology.

Results: A total of 2516 participants were included in this study of whom 66 had glaucomatous visual field loss in at least one eye and 1680 fulfilled the criteria for contributing to the normative values. The HRT3 linear cup-disc ratio (LCDR) variable, adjusted for disc area, showed the highest sensitivity, 35%, at the required specificity of 97.5%. The 97.5th percentile of the LCDR was 0.67 for small discs (up to 1.5mm²), 0.73 for medium-sized discs and 0.79 for large discs (above 2.0mm²). The HRT3 Glaucoma Probability Score and previously published linear discriminant functions showed a lower sensitivity than LCDR at this specificity.

Conclusions: At the high specificity of 97.5% as is commonly used in population-based epidemiology, the sensitivity of the HRT3 is low ? albeit not lower than that of the vertical cup-disc ratio as assessed with simultaneous stereoscopic fundus photography and analyzed with the ImageNet software. The LCDR variable, stratified for disc area, seems to be the most suitable variable to develop criteria for glaucomatous optic neuropathy for epidemiological purposes.     

青光眼视乳头地形图积分诊断模式研究

目的:对正常人与原发性开角型青光眼(primary open angle glaucoma,POAG)视乳头地形图参数进行比较,建立POAG视乳头地形图积分诊断模式并进行诊断。方法:对116例(116只眼)正常、63例(99只眼)连续性POAG患者和42例(75只眼)早期POAG患者进行海德堡视网膜断层扫描(Heidelberg Retina Tomograph,HRT)检查,进行视乳头地形图参数的比较:根据青光眼和正常人视乳头地形图参数分布的50％、95％和99％分布范围,分别记积分-4、-3、-2、-1、1、2、3、4分,以积分总和为变量进行诊断分析,以95％的特异性分别作出正常人和青光眼的肯定诊断,对不能作出肯定诊断的患者视为可疑青光眼。结果:正常人与青光眼患者视乳头地形图各参数具有显著性差异;运用积分诊断法,对连续病例POAG与正常资料进行判断的漏诊率为6.1％,误诊率为5.2％,确诊率为57.6％,疑诊率为36.4％;对早期青光眼与正常人资料进行的漏诊率为10.7％,误诊率为5.2％,确诊率为36％,疑诊率为53.3％。结论:正常人与青光眼患者的视乳头地形图参数具有明显差异,运用积分法可将受检人群分...     

Clinical and experimental findings in Acanthamoeba keratitis with Heidelberg Retina Tomograph III-RCM.

PURPOSE: To observe Acanthamoeba cysts and trophozoites in the corneal tissue of patients and rabbits with Acanthamoeba keratitis (AK), using the Heidelberg Retina Tomograph III Rostock-cornea-module (HRTIII-RCM). METHODS: Eight eyes of seven patients with clinical and laboratory diagnosis of AK, presenting to the Beijing Institute of Ophthalmology between July and December 2006, were included in this study. The laboratory diagnosis in all cases was established by a cytological analysis and culture of the corneal scraping. The scanning with HRTIII-RCM was performed on all the patients. Acanthamoeba cysts and trophozoites in the corneas of three rabbits were observed with the HRTIII-RCM after a suspension of trophozoites was injected into the corneal stromal layer of the rabbits. RESULTS: Acanthamoeba cysts or trophozoites were observed with the HRTIII-RCM in the corneas of all the patients. The size and shape of Acanthamoeba in the tissue of the rabbit corneas was consistent with that in the patients' eyes. The Acanthamoeba cyst presented a round high-contrast particle, 15-20 microm in diameter, with a double wall. In contrast, the trophozoite presented an irregular high-contrast particle, without an apparent wall, 25-40 microm in diameter and with a round conspicuous nucleus. CONCLUSIONS: HRTIII-RCM is a useful non-invasive clinical technique to help to diagnose and monitor the response of AK to therapy.     

Reproducibility of volumetric macular measurements in diabetic patients with the Heidelberg Retina Tomograph

Aims: To quantify diabetic macular edema by confocal scanning laser ophthalmoscopy and assess its usefulness by determining the reproducibility of topographic measurements at the macula. Methods: The volumes above reference plane bound by a 2 mm diameter circle centred on the fovea were measured by two observers. The reference plane was adjusted to the lowest point of the height variation of the contour line. The reproducibility of this technique was assessed in 20 eyes of 20 diabetic patients of which 8 eyes had macular edema. Three HRT scans of each eye were obtained. The measurements of volume above reference plane of each scan were repeated three times. Results: For all diabetic eyes, the intra scan coefficients of variability measured 14.71% to 21.21%, the inter scan coefficient of variability was 30.46%. The average standard deviations were 0.053 mm³ for one examination per scan, 0.047 mm³ for two examinations per scan and 0.044 mm³ for three examinations per scan. Linear regression demonstrated an increase in standard deviation with greater volumetric measurements (p < 0.001). We found good correlation (r = 0.959, p < 0.001) and strong agreement between the two observer's findings for all 20 eyes. For the 8 eyes with macular edema, the coefficients of variability were similar to those calculated for all 20 eyes. The average SD for one examination per scan were 0.078 mm³, 0.069 mm³ for two examinations per scan and 0.062 mm³for three examinations per scan. We found good correlation (r = 0.945, p < 0.001) and strong agreement between the two observer's findings in eyes with edema. Conclusion: The reproducibility of this technique has been demonstrated in diabetic eyes. This may have useful clinical applications for the quantification of diabetic macular edema and monitoring of laser therapy. This revised version was published online in July 2006 with corrections to the Cover Date.     

Diagnostic accuracy of Heidelberg Retina Tomograph III classifications in a Turkish primary open‐angle glaucoma population

Purpose: This study aimed to evaluate the diagnostic accuracy of Moorfields regression analysis (MRA) and the glaucoma probability score (GPS) in primary open‐angle glaucoma (POAG) and to measure the level of agreement between the two algorithms in classifying eyes as normal or abnormal in a Turkish population. Methods: We prospectively selected 184 healthy subjects and 158 subjects with POAG, who underwent an ophthalmological examination, visual field analysis and imaging with the Heidelberg Retina Tomograph II, using HRT III software, Version 3.0. The diagnostic accuracies of the two classifications were measured when the borderline was taken as either normal (highest specificity criteria) or abnormal (highest sensitivity criteria). The agreement between them was calculated using the unweighted kappa (κ) coefficient. Results: Optic nerve head topographic parameters showed statistically significant differences between the control and POAG groups (p < 0.001). The parameters with the highest area under the receiver operating characteristic curves were global GPS (0.86), cup : disc area (0.85), rim : disc area (0.85) and vertical cup : disc (0.85). According to the highest specificity criteria, MRA had a sensitivity of 67.7% and a specificity of 95.1%, whereas the GPS had a sensitivity of 70.9% and a specificity of 88.0%. According to the highest sensitivity criteria, MRA had a sensitivity of 81.0% and a specificity of 75.0%, whereas the GPS had a sensitivity of 89.2% and a specificity of 57.6%. A moderate agreement of 68% (233 eyes) with a κ coefficient of 0.51 was found between MRA and the GPS. Conclusions: The GPS automated classification showed similar sensitivity to MRA, but considerably lower specificity, when applied in a Turkish population.