原发性开角型青光眼视乳头旁脉络膜萎缩区的双眼对照研究

目的研究单眼视野缺损的原发性开角型青光眼患者双眼间视乳头旁脉络膜萎缩区（PPA）的出现频率和面积大小差异。方法利用计算机图像分析系统对视乳头立体照相进行测量,比较40例单眼视野缺损的原发性开角型青光眼患者双眼间PPA的发生率及大小差异。所有入选患者的屈光度（等效球镜）均在-3．00-＋3．00D之间。结果视野缺损眼的视杯面积、杯盘面积比均大于视野正常眼,差异有统计学意义（视杯面积：t=5．332,P〈0．01;杯盘面积比：t=5．126,P〈0．01）。视野缺损眼的α区面积略大于视野正常眼,差异有统计学意义（t=3．02,P=0．0045）;双眼间β区面积差异无统计学意义（S：13．5,P=0．426）;双眼α区与β区的发生率均存在一致性（α区：Х^2=0．00,P=1．000;β区：Х^2=1．2857,P=0．2568）。结论在排除了-3．00D以上的中高度近视眼人群后,单眼视野缺损的原发性开角型青光眼α区、β区的有无和13区的大小均不能很好地反映双眼间视野缺损的差异。     

眼灌注压对人视乳头微循环的影响

目的 了解眼外负压吸引诱导的眼灌注压改变的条件下，正常人、原发性开角性青光眼(POAG)患者和正常眼压性青光眼患者(NTG)的视乳头微循环的变化，探讨视乳头局部自身调节的幅度。方法正常人8例，POAG患者10例和NTG患者7例，采用眼外负压杯吸引诱导眼压升高，负压增加的幅度为30s50mmHg，同时测量眼压。采用HRF测量视乳头处血流量。将基础状态下视乳头血流值作为基础值，当眼压升高到30mmHg和40mmHg时，分别测量这两点视乳头微循环的血流值，在40mmHg后解除负压吸引，测量负压吸引解除后1min、5min时视乳头微循环的血流值。结果 三组视乳头的基础血流量无明显差异。当眼压升高到30mmHg时，正常组的血流量仍维持稳定，但POAG组和NTG组明显下降，POAG组下降幅度超过25％，NTG组下降幅度超过45％。当眼压升高到40mmHg，正常组视乳头血流量也出现明显下降，其中0NHF下降约30％，POAG组和NTG组下降更明显，POAG组下降幅度超过50％，NTG组下降幅度超过65％。在解除负压吸引后1min，正常组血流量增加的幅度约为31％，POAG组增加约19％，NTG组无明显增加。在负压解除后5min，三组视乳头血流基本恢复到基础状态。结论 正常组视乳头微循环有一定范围的自身调节幅度，可以耐受眼灌注压一定程度的改变，POAG组和NTG组自身调节能力均有不同程度的损害。     

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)     

正常眼压性青光眼患者视盘区血管密度与视野指数和视野损伤形态的关系

目的：研究正常眼压性青光眼(NTG)视盘区血管密度变化与青光眼视野指数(VFI)和视野损伤形态分期的关系。

方法：选取我院2018-12/2020-12 NTG患者106例106眼和原发性开角型青光眼(POAG)患者79例79眼进行横断面研究,其中双眼病变者采用随机数字表选取1眼为样本,同时选取我院健康体检者92名为对照组,三组均完成视盘血管密度、VFI检测和视野缺损形态分期,然后分析视盘血管密度与VFI和视野缺损形态分期的关系。

结果：POAG组眼压明显高于NTG组和对照组(P<0.05); NTG组和POAG组视盘区全区域血管密度、大血管密度和毛细血管密度均明显低于对照组(P<0.05),无血管区密度均明显高于对照组(P<0.05),且NTG组和POAG组各项指标比较有差异(P<0.05); NTG组和POAG组VFI均明显低于对照组(P<0.05),视野平均缺损(MD)明显高于对照组(P<0.05),且NTG组和POAG组VFI和MD比较无差异(P>0.05); 随着视野缺损形态分期增加,NTG患者视盘全区域血管密度和毛细血管密度呈明显降低趋势(P<0.05); NTG患者视盘全区域血管密度和毛细血管密度与VFI呈正相关性,与视野缺损形态分期呈负相关性,无血管区密度与VFI呈负相关性,与视野缺损形态分期呈正相关性(均P<0.05)。

结论：NTG患者视盘血管密度较POAG患者和正常人群明显降低,且与VFI和视野缺损形态分期存在明显相关性,其中以毛细血管密度相关程度最高,可见OCTA对NTG诊断、治疗和随访均具有重要临床意义。     

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旁萎缩弧β区5年变化研究

目的：探讨原发性开角型青光眼(primary open angle glaucoma,POAG)视盘旁萎缩弧β区的变化和POAG进展之间的关系。

方法：本研究为回顾性病例研究。对POAG 44例66眼进行5a的随访,其基线和5a随访时的所拍摄的眼底照片用于视盘形态学的评估。本研究对前后视盘旁萎缩弧β(β区)的变化和青光眼进展进行判断,并且用计算机软件测量了POAG患者基线和随访时盘沿/视盘面积比、β区/视盘面积比、垂直杯盘比。

结果：基线时66眼POAG眼有48眼存在β区,其中β区扩大20眼(42%)。β区扩大组和无变化组之间基线的年龄,屈光,性别,垂直杯盘比,盘沿/视盘面积比,β区/视盘面积比之间无统计学差异。排除屈光度数大于-3.00D的眼后,19例无进展青光眼中β区扩大4例(21%),25例进展青光眼中β区扩大15例(60%),两者之间有显著统计学差异(χ²=6.67,P=0.011)。

结论：POAG中有β区扩大组青光眼进展率大于无扩大组,β区的变化可能对POAG病情的进展有预测作用。     

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。     

不同类型青光眼和正常人视盘旁萎缩弧β区的比较研究

目的 比较正常人和原发性开角型青光眼(POAG)、闭角型青光眼(PACG)之间视盘旁萎缩弧β区发生率的差异以及其与视盘参数的关系.设计 病例对照研究.研究对象 年龄、屈光度数相匹配的正常人、POAG、PACG分别为143例(143眼)、59例(105眼)、50例(87眼).方法 利用Cannon眼底照相机采集受试者30°眼底彩色照片,并用计算机图像分析软件测量β区面积、视盘面积;青光眼患者测量盘沿面积、垂直杯盘比,对青光眼患者β区/视盘面积比和盘沿/视盘面积比、垂直杯盘比进行Spearman相关分析.主要指标 β区发生率、β区面积.结果 正常人、POAG及PACG者β区发生率分别为23.1%、69.5%、50.6%(P=0.000);POAG的β区发生率高于PACG(P=0.007).三组人群β区最多见于水平颞侧区,鼻侧区最少;POAG组β区/视盘面积比与盘沿/视盘面积比呈负相关(r=-0.370),与垂直杯盘比呈正相关(r=0.342).PACG组β区面积/视盘面积比与盘沿面积/视盘面积比和垂直杯盘比之间均无显著性相关.结论 POAG和PACG β区发生率高于正常人,POAG β区发生率高于PACG.PACG和POAG β区与视盘参数之间相关关系的差异可能和两者视神经损伤的机制不同有关.(眼科,2008,17:20-24)     

正常眼压性青光眼、原发性开角型青光眼患者及正常人DCT眼压及OPA的比较性研究

目的探讨在原发性开角型青光眼(PrimaryOpenAngleGlaucoma,POAG)及正常眼压性青光眼(NormalTensionGlaucoma,NTG)患者使用动态轮廓眼压计(DynamicContourTonometer,DCT)测量时的影响因素。方法POAG、NTG及正常对照组各31例,测量了Goldmann压平眼压(GoldmannApplanationTonometer,GAT)、DCT眼压、眼脉动幅度值(OcularPulseAmplitude,OPA)、以及心率(HeartRate,HR)、收缩压(SystolicBloodPressure,SBP)、舒张压(DiastolicBloodPressure,DBP)等指标,评估GAT、DCT两种眼压计测量的一致性,分析测量中的影响因素,并比较三组被检者OPA的差异;结果除HR以外(P=0.130),三组被检者的DCT眼压、OPA、GAT眼压、HR、SBP及DBP均存在显著性差异(P<0.05)。其中,正常对照组OPA为(2.85±1.15)mmHg,NTG组为(1.99±1.04)mmHg,POAG组为(3.00±1.07)mmHg,POAG组与正常对照组比较差异(P=0.568)无显著性意义,与NTG组比较差异有显著性意义(P<0.001),NTG组与正常对照组(P=0.003)比较有显著性意义;结论DCT眼压和GAT眼压表现出良好的一致性,DCT的测量结果可信;POAG、NTG患者和正常人的OPA存在差异。     

慢性闭角型青光眼视野损害的特点

目的　为了了解早中期慢性闭角型青光眼 (chronicangleclosureglaucoma ,CACG)的静态视野损害特点。对象与方法　对象为MD≤ 15dB的慢性青光眼患者 81例 81只眼 ,其中CACG 2 7例 2 7只眼 ,正常眼压性青光眼 19例 19只眼 ,和原发性开角型青光眼 3 5例 3 5只眼。采用Octopus10 1视野计G2程序 ,将视野内 5 9个静点划分为 9个区和中央 1个点 ,通过图中各点的值 ,分别计算每只眼的每个点、区的MD ;再将视野以 0°～ 180°为界 ,分成上下两个半侧视野 ,分别计算和比较上方和下方半侧视野的MD和LV ;最后对中央 9个点 (6°范围 )进行受累情况的判断 ,并进行CACG、POAG和NTG三组组内和组间的比较。结果　CACG组的中央区MD比POAG NTG组要小 (Z =-2 0 69,P =0 0 3 9) ,其余各区和中心点差异无显著性 (Z =-0 0 6～ 1 72 1,P =0 0 9～ 0 95 2 ) ;CACG和POAG上方半侧视野的MD明显比下方的MD要大 (P =0 0 2 4和 0 0 10 ) ,而NTG的上下方视野MD差异无显著性 (P =0 0 77)。CACG、NTG和POAG中央 6°视野的受累率分别是 2 5 9%、5 7 9%和 5 1 9% (P =0 0 40 )。结论　CACG上方半侧视野比下方受损明显 ,与POAG/NTG视野改变模式有所不同的是 ,中央视野比较不易受损。     

开角型青光眼视盘周围脉络膜萎缩与视野缺损的相关性研究

目的:探讨原发性开角型青光眼(primaryopenangleglaucoma,POAG)和可疑开角型青光眼(suspectedopenangleglaucoma,SOAG)视盘周围脉络膜萎缩(peripapillarychoroidalatrophy,PPCA)的发生率及不同分区的面积大小与视野指数平均缺损(Meandefect,MD)之间的相关性。方法:对128只POAG和78只SOAG行静态视野检查及眼底视盘彩色照相,对有PPCA改变的视盘确定其α区和(或)β区,并测出不同分区的面积。结果:POAG组中,PPCA的α和β区的发生率分别为57.03%和39.84%,面积均数分别为(0.54±0.37)mm2和(1.68±1.06)mm2,MD为(8.31±3.66)dB;SOAG组中,α和β区的发生率分别为43.59%和26.92%,面积均数分别为(0.42±0.29)mm2和(1.15±0.67)mm2,MD则为(4.16±2.07)dB。在2组病例中,α区和β区面积值与MD之间均具有显著意义的正性相关(P<0.001)。结论:PPCA不同分区的面积值与MD之间具有显著相关性;β区的发展是辨认青光眼或青光眼性视神经损害是否进展的重要参数,有助于发现及预测青光眼病情的发展。     

Ability of peripapillary atrophy parameters to differentiate normal-tension glaucoma from glaucomalike disk

PURPOSE: To investigate the ability of peripapillary atrophy (PPA) parameters to differentiate normal-tension glaucoma (NTG) from glaucomalike disk (GLD). METHODS: Thirty-three eyes of 33 patients with GLD that had no evidence of visual field defect and retinal nerve fiber layer defect and 33 eyes of 33 patients with NTG, matched with age and intraocular pressure, were enrolled. The participants were selected from the database of patients referred from a routine health checkup because of high cup-to-disk ratio (>0.5). Topographic measurements for the optic disk were performed using the Heidelberg Retina Tomograph (HRT). The extent of PPA (zone beta) was measured with Atrophy Zone Analysis software of HRT. Receiver operating characteristic (ROC) curves (GraphROC version 2.0) were used to compare the new formula including PPA parameters with that of the HRT discriminant analysis formula in differentiating NTG from GLD. RESULTS: The area of zone beta, atrophy-to-disk area ratio, and angular and radial extent of zone beta were significantly larger in NTG (P < 0.01). Multiple logistic regression analysis showed that rim area and corrected radial extent of zone beta are variables that show significant difference between NTG and GLD (P < 0.05). The area under the ROC curve for the new formula including rim area and corrected radial extent of zone beta (0.8655) was significantly larger than that for the HRT discriminant analysis formula (0.7351) (P = 0.0128). CONCLUSION: The PPA measurement obtained by HRT can be a useful additional tool to differentiate NTG from GLD after the first screening by disk photograph in a routine health checkup.     

Open-angle glaucoma clinical presentation and management]

Both primary open-angle and normal-tension glaucoma belong to an identical spectrum of diseases. Clinical presentations of primary open-angle or high-tension glaucoma (POAG) and normal-tension glaucoma (NTG) were studied in an attempt to determine prognostic, clinical factors and define the appropriate management. Clinical data obtained from 826 primary open-angle and normal-tension glaucoma patients were analyzed. In addition, the results of laboratory studies, including the immunological assay of heat shock protein (hsp) and gene analyses which were undertaken to identify risk factors at the molecular level, are discussed. 1. The identified prognostic factors were disk hemorrhage, peripapillary chorioretinal atrophy (PPA), maximum intraocular pressure (IOP), the recovery rate of skin temperature after exposure to cold, family history of glaucoma, systemic systolic channel blood pressure, and oral administration of Ca(2+)-channel antagonists. 2. Disk hemorrhage was observed in 30.5% of NTG patients and 15.4% of POAG patients. Cumulative probability of hemorrhagic events was 16.9% in POAG and 38.4% in NTG patients at the end of a 14.8-year follow-up. 3. The hazard ratio of disk hemorrhage decreased with the increase of IOP(26%/5 mmHg) and was 1.46 times higher in females than in males. Disk hemorrhage was closely associated with PPA: PPA becomes greater in association with the progression of glaucomatous optic neuropathy in both POAG and NTG. No such correlation was noted in primary angle-closure glaucoma. 4. Color Doppler imaging analyses and the hourly determination of ocular perfusion pressure (OPP) indicated a difference in retrobulbar hemodynamics between OPP-mean deviation concordant and OPP-mean deviation discordant patients: a circulatory disturbance causally unrelated to OPP seems to be involved in the OPP-mean deviation discordant patients. 5. The oral administration of Ca(2+)-channel antagonists was shown to favorably influence retrobulbar hemodynamics in NTG patients. 6. Serum antigen titer to hsps(hsp 27, alpha B crystallin, human & bacterial hsp 60) was higher in both POAG and NTG patients than in normal subjects. None of the hsp-antigens was correlated to any morphometric parameters of the optic disk or any global indices of the visual field. 7. Myocilin mutation was noted in only 0.5% of POAG patients and 2.37% of NTG patients. The very low rate of occurrence precludes the value of mutation of the gene as a prognostic factor in open-angle glaucoma(OAG). 8. IOP reduction achieved by mitomycin-C trabeculectomy is effective in maintaining visual function in OAG eyes. 9. Brovincamine fumarate is effective in inhibiting the progression of glaucomatous field loss in NTG.     

Specificity and sensitivity of glaucoma detection in the Japanese population using scanning laser polarimetry.

AIMS: To investigate the usefulness of the scanning laser polarimeter (GDx; GDx Nerve Fiber Analyzer) for glaucoma detection in the Japanese population, and to investigate the difference in the thickness of retinal nerve fibre layer (RNFL) between normal tension glaucoma (NTG) and primary open angle glaucoma (POAG). METHODS: 69 eyes of 69 normal subjects and 115 eyes of 115 chronic open angle glaucoma patients (60 NTG and 55 POAG patients) were studied. The thickness of RNFL was measured with GDx. An eye was diagnosed as glaucomatous, if at least one original GDx variable showed p <5%. The difference in thickness of RNFL between the NTG and POAG groups was then investigated. RESULTS: 46 normal eyes (66.7%) were diagnosed as not glaucomatous (no variables showing p <5%), and 93 glaucomatous eyes (46 NTG and 47 POAG eyes) (80.9%) were diagnosed as glaucomatous. Actual values of average thickness, ellipse average, superior average, and superior integral were significantly lower in the POAG group than those in the NTG group. CONCLUSIONS: New variables which elucidate focal RNFL defects or early changes are needed to improve the moderate detection ability found in this present study. The pattern of the change in RNFL may differ in NTG and POAG groups.     

原发性开角型青光眼HRT视盘结构参数与视野缺损相关性研究

目的探讨出现视野缺损与未出现视野缺损的原发性开角型青光眼视盘结构参数的异同及视盘参数与视野平均缺损（MD）的相关性。方法应用海德堡视网膜断层扫描仪（HRT-Ⅱ）和Octopus101视野G2程序对29例（50只眼）原发性开角型青光眼患者进行检查，对出现视野缺损与未出现视野缺损的原发性开角型青光眼视盘结构参数进行比较，检测结果进行t检验；对出现视野缺损的原发性开角型青光眼组的视盘各参数与视野平均缺损进行简单相关分析。结果视野出现缺损组与未出现缺损组的原发性开角型青光眼患者的视盘参数除视盘面积和轮廓线高度变化值外，其余各视盘参数间差异均有显著性（P〈0．01）；对出现视野缺损的原发性开角型青光眼患者HRT视盘各参数与MD进行相关分析显示，盘沿面积与MD间相关性最强（r=0．65，P=0．001）。结论HRT视盘参数能够较准确反映与视野损害相一致的青光眼性视盘改变，盘沿面积在HRT众多参数中最能反映青光眼的视野平均缺损程度。     

Comparing glaucomatous optic neuropathy in primary open angle and chronic primary angle closure glaucoma eyes by optical coherence tomography

PURPOSE: To comparatively evaluate the optic nerve head (ONH) using Optical Coherence Tomography (OCT) in normal subjects, primary open angle glaucoma (POAG) and chronic primary angle closure glaucoma (CPACG) patients. METHODS: A total of 138 normal eyes (138 subjects) and 139 glaucomatous eyes (139 patients), were evaluated in this cross-sectional observational study. The ONH was imaged on OCT using the optic disc scan. Disc area, cup area, rim area, vertical integrated rim area (VIRA), rim volume (horizontal integrated rim volume), average cup/disc ratio, horizontal and vertical cup/disc ratios, and cup volume were evaluated. Additionally, cup depth and slope of the temporal ONH were also measured. These ONH parameters were compared between normal subjects and eyes with early POAG and CPACG. Correlation of mean deviation and corrected pattern standard deviation on full threshold 30-2 perimetry, with measured ONH parameters was carried out amongst the two groups. RESULTS: There was a significant difference in disc area (2.38 +/- 0.5, 2.77 +/- 0.4, 2.62 +/- 0.4 mm(2), p < 0.01), cup area (0.88 +/- 0.6, 1.99 +/- 0.7, 1.60 +/- 0.7 mm(2), p < 0.01), rim area (1.48 +/- 0.4, 0.86 +/- 0.4, 0.96 +/- 0.4 mm(2), p < 0.01), VIRA (1.64 +/- 0.3, 1.23 +/- 0.3, 1.22 +/- 0.4 mm(2), p < 0.01), rim volume (0.34 +/- 0.2, 0.1 +/- 0.1, 0.15 +/- 0.1 mm(3), p < 0.01) and cup/disc ratio (0.36 +/- 0.2, 0.69 +/- 0.1, 0.63 +/- 0.2, p < 0.01) in normal vs POAG vs CPACG eyes respectively. A comparison of ONH parameters between early POAG and early CPACG showed a significant difference in the disc area (2.85 +/- 0.3, 2.57 +/- 0.4 mm(2), p = 0.03), cup area (2 +/- 0.5, 1.34 +/- 0.5 mm(2), p < 0.01), rim area (0.96 +/- 0.4, 1.21 +/- 0.5 mm(2), p = 0.009), rim volume (0.12 +/- 0.1, 0.18 +/- 0.1 mm(3), p < 0.01) and cup/disc ratio (0.67 +/- 0.1, 0.53 +/- 0.2, p < 0.01). The parameters with the highest area under the receiver operator characteristic (AROC) curves for differentiating normal and early POAG eyes were rim volume, 0.89, VIRA, 0.84, and rim area, 0.76. The AROC values (normal vs early CPACG eyes) were 0.75 for rim volume, 0.72 for VIRA, and 0.66 for rim area. CONCLUSION: OCT may serve as a useful diagnostic modality in distinguishing a normal optic disc from a glaucomatous one, even in the early stages of glaucoma. Rim volume, VIRA and rim area can be used to differentiate normal from early glaucoma (both early POAG and CPACG), and most efficiently early POAG eyes. CPACG eyes have smaller discs, a smaller cup, smaller cup/disc ratio, and a larger rim area when compared with eyes with POAG.