HRT在青光眼诊断和视神经监测中的应用

HRT是一种自动化的电子计算机控制的共焦激光眼底断层扫描仪。利用它可以获取视盘的三维地形图 ,通过对图像的分析处理 ,得到视盘和视网膜神经纤维层厚度的定量描述 ,并且可用于地形图变化的定量分析。本文就HRT的工作原理和技术参数及其在青光眼诊断和视神经损害监测中的应用作一综述。     

HRT在青光眼诊断和视神经监测中的应用

HRT是一种自动化的电子计算机控制的共焦激光眼底断层扫描仪。利用它可以获取视盘的三维地形图，通过对图像的分析处理，得到视盘和视网膜神经纤维层厚度的定量描述，并且可用于地形图变化的定量分析。本文就HRT的工作原理和技术参数及其在青光眼诊断和视神经损害监测中的应用作一综述。     

OCT测量视网膜神经纤维层厚度及视盘参数在青光眼早期诊断中的应用

青光眼是一种进行性视神经疾病,它能引起视神经结构改变,最终导致不可逆的视功能损害。青光眼的早期诊断对保护视功能有重要意义。光学相干断层扫描仪是一种准确性和可重复性高的视网膜神经纤维层厚度和视盘参数检测技术,为早期诊断青光眼,监测视神经损害及指导青光眼的治疗提供了新的思路。我们主要阐述该技术在青光眼早期诊断中的应用。     

视觉电生理技术在青光眼早期诊断中的意义

青光眼是一组威胁和损害视神经及其视觉通路,最终导致视觉功能损害的疾病。青光眼视神经损害以视网膜神经节细胞( retinal ganglion cells,RGCs)及其轴突数目进行性丢失、视盘凹陷、视野缺损为特征。静态自动视野计检查是评估青光眼病程进展的金标准,但其结果往往受到患者主观因素的限制。近年来视觉电生理技术飞速发展,虽还不能代替传统的视野检查,但作为补充,其能在青光眼视野缺损前即出现振幅及潜伏期的改变,为早期青光眼的诊断提供了新的参考思路。本文主要对三种特殊类型的视网膜电图以及多焦视觉诱发电位在青光眼早期诊断中的意义进行综述。     

OCT在病理性近视眼视盘神经纤维层厚度检测中的应用

目的：应用频域光学相干断层扫描成像（optical coherence tomography,OCT）技术研究病理性近视眼视盘神经纤维层厚度的变化特点及其与眼轴、性别和年龄的关系,为病理性近视合并原发性开角型青光眼的早期诊断提供帮助。方法：选取对照组正常眼96眼（眼轴23～24mm）和观察组病理性近视眼153眼（眼轴25～27mm 80眼,〉27mm 73眼）; 应用频域OCT检测视盘神经纤维层的厚度; 比较对照组与观察组视盘神经纤维层厚度的差异; 使用多元线性回归分析观察组视盘全周的平均厚度与眼轴、性别和年龄的关系。结果：观察组视盘神经纤维层的全周平均、上下及鼻侧象限平均厚度值均变薄,与对照组相比均具有统计学意义（P〈0.05）,颞侧象限相比较无统计学意义（P〉0.05）; 观察组视盘神经纤维层的全周平均厚度与眼轴的偏相关系数为-1.31,与性别的偏相关系数为5.21,与年龄的偏相关系数为-0.12。结论：病理性近视眼的视盘神经纤维层厚度较正常眼变薄,眼轴、性别和年龄是病理性近视眼视盘神经纤维层平均厚度的影响因素,对诊断合并病理性近视患者的青光眼视神经损害时应注意排除病理性近视对视盘神经纤维层厚度产生的影响。     

病理性近视视盘及其相关结构的形态学改变

病理性近视眼的视盘及其相关结构的形态学改变,包括视网膜神经纤维层厚度改变、视盘形态改变等,由此可引起相应的视功能改变.病理性近视眼因后巩膜葡萄肿的形成及生物力学特性的改变,可能导致视神经的结构和功能发生异常.这其中一些变化可能与青光眼的发生密切相关,或者对青光眼诊断造成困扰.     

青光眼视神经损害的分级评估方法

青光眼视神经损害的分级对青光眼诊断、治疗方法选择和病情评价等均有重要价值。本文介绍了目前国际上常用的几种青光眼视神经损害分级方法。视盘形态学分级方法包括杯盘比、Shiose法、Richardson法、Nesterov法、Jonas法和视盘损伤可能度等;视网膜神经纤维层评估法包括Quigley分期法、眼底照片参照分级法等。     

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。     

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.     

黄斑内层视网膜厚度测量在青光眼早期诊断和随访中的应用

青光眼是一组以视盘凹陷性萎缩和视野进行性损害为特点的不可逆性致盲眼病。传统视野“金标准”及视网膜全层厚度测量在青光眼诊断中具有一定的滞后性和局限性,而黄斑区内层厚度测量由于其生理优势可能有助于早期青光眼诊断。目前快速发展的OCT技术已经能够分离测量视网膜黄斑内层厚度,至今也已有多篇文献报道黄斑内层厚度测量在早期青光眼中具有较好的诊断效能且发现其基线指标可能对青光眼进展有预测价值。     

Imagings of glaucoma: characteristics of ocular configurations and automated diagnosis

Glaucoma is characterized by the coexistence of structural changes in the fundus and the corresponding functional abnormalities. The advances in imaging devices that reveal structural changes in glaucoma should facilitate reliable diagnosis of early or preperimetric glaucoma and a proper evaluation of glaucoma progression. Moreover, the increase in our knowledge of structural changes in glaucoma will provide a better platform for investigating up to now unknown glaucoma etiologies. In this review, we summarize a series of our clinical investigations of glaucoma imaging technologies. The diagnostic performance of Heidelberg Retina Tomograph (HRT) II and the characteristics of the HRT II parameters in high myopia were studied with population-based data to provide data for nerve head configuration; the correlation of parameters determined by planimetry of optic disc stereophotography with the results of the HRT II was evaluated; optic disc parameters were determined based on spectral-domain optical coherence tomography (SD-OCT); and optic disc configurations were evaluated in eyes with peripapillary atrophy and eyes with superior segmental optic nerve hypoplasia. Peripapillary retinal nerve fiber layer (RNFL) thickness was determined with SD-OCT in normal Japanese eyes; and the diagnostic performance of RNFL thickness was studied. The characteristics of each layer, including retinal nerve fiber layer, ganglion cell layer, and each complex layer in the macular area, and their correlation with the stages of glaucoma were evaluated. Finally, imaging of the anterior chamber angle using ultrasound biomicroscopy (UBM) were studied about the distribution of the UBM parameters in a Japanese population and the factors relating to the presence of peripheral anterior synechia in narrow angle eyes.     

High tech in the diagnosis of glaucoma

Scanning laser tomography (HRT, HRT II), scanning laser polarimetry (GDx nerve fibre analyser, GDx VCC), retinal thickness analyser (RTA) and optical coherence tomography (OCT, stratus OCT) provide objective measurements of the optic disc and the retinal nerve fibre layer suitable for the follow-up of glaucoma patients. Their ability to diagnose early glaucomatous damage is still limited but promising technical advances in this field can be expected in the future. For the moment, clinical examination and fundus photography still remain the gold standard for the assessment of glaucomatous optic disc and retinal nerve fibre layer damage.     

New findings in the evaluation of the optic disc in glaucoma diagnosis

PURPOSE OF REVIEW: Ophthalmoscopical evaluation of the optic disc is a feasible and largely accessible method to diagnose glaucoma. Many qualitative parameters have been described in glaucomatous optic neuropathy. Considering individual variations in the details of topography or tissue components damaged by the glaucomatous process, however, adequate identification of glaucomatous optic disc signs requires training and experience. Without adequate guidelines of optic disc examination, the physician may miss important aspects that could lead to adequate diagnosis or identification of progression in a patient with established glaucoma. This paper presents a systematic approach for the examination of the optic disc and retinal nerve fiber layer to aid the detection of glaucoma. RECENT FINDINGS: Optic disc qualitative parameters are better than quantitative parameters in separating glaucomatous from normal eyes. The sequential evaluation of optic disc size, neuroretinal rim size and shape, retinal nerve fiber layer, presence of peripapillary atrophy, and presence of retinal or optic disc hemorrhages enhances the ability to detect glaucomatous damage and its progression. SUMMARY: Ophthalmologists should be familiar with glaucomatous optic disc signs that can be identified during clinical examination. A simple systematic approach may allow improved diagnosis and management of glaucoma.     

New technologies for diagnosing and monitoring glaucomatous optic neuropathy.

BACKGROUND: Recently, instruments have been developed to provide real-time, quantitative measurements of the optic disc and retinal nerve fiber layer (RNFL) for use in glaucoma management. Our objective is to (1) provide an overview of two of these instruments, the confocal scanning laser ophthalmoscope (Heidelberg Retina Tomograph, HRT) and scanning laser polarimeter (Nerve Fiber Analyzer, NFA) and (2) compare measurements obtained with these instruments to clinical features used in the diagnosis of glaucoma. METHODS: Twenty glaucoma patients, 4 normal subjects and 20 glaucoma subjects were included. All subjects had images obtained with the HRT and NFA, and RNFL and optic disc photography completed within 5 weeks of each other. The HRT results were compared with qualitative evaluation of stereophotographs of the optic disc, and NFA results were compared against a semi-quantitative RNFL photograph severity score. RESULTS: Twenty-five (57%) subjects had thinning of the neuroretinal rim identified by evaluation of stereoscopic optic disc photographs. Despite overlap, HRT measurements of rim volume, rim area, and rim/disc ratio were significantly smaller in eyes with evidence of rim thinning than in eyes with no evidence of rim thinning. Moderate to severe RNFL damage was detected by evaluation of photographs in 25 (57%) of subjects. NFA RNFL thickness measures were smaller in eyes with moderate to severe RNFL damage than in relatively healthy eyes. CONCLUSIONS: Previous studies have documented the reproducibility of these instruments and suggested analytic techniques for improving their ability to differentiate between normal and glaucoma eyes. Our results indicate that despite overlap in values, these instruments provide measurements that reflect clinically relevant features of the optic disc and RNFL. Whether these technologies can improve our ability to detect glaucomatous progression over time needs to be determined with well-designed longitudinal studies and comparison with established diagnostic techniques for evaluating glaucomatous optic neuropathy.     

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。     

视盘倾斜及其相关性研究现状

视盘在垂直和水平轴位上出现的一侧表面抬高被称之为视盘倾斜.倾斜视盘在人群中并不少见,而倾斜的形态对于视盘结构自身以及盘周如神经纤维层厚度、脉络膜厚度等结构的临床测量及视野等结果分析造成困难.视盘倾斜的方向和程度及视盘周围眼部结构与眼病如近视、青光眼等可能具有相关性.对视盘倾斜程度进行量化研究,可确切评估视盘形态和校正其对周围视网膜结构的测量误差.通过准确的视盘倾斜程度的测量,并前瞻性观察视盘倾斜的程度变化,有助于揭示近视、青光眼相关的发病机制,并为分析相关疾病进展提供科研基础以及临床生物学指标.     

高度近视合并青光眼的临床诊断研究进展

众多研究表明高度近视是青光眼性视神经病变的高危因素。然而,由于高度近视本身会引起视网膜和视神经纤维层损伤,所以青光眼相关的结构和功能改变可能会被高度近视掩盖。为了在高度近视患者中早期识别出青光眼性改变,减少漏诊或误诊的可能性,深入了解高度近视合并青光眼的临床特征是非常必要的。本文概括了经典的结构和功能检查在诊断高度近视合并青光眼中的作用以及存在的困难,并针对这一诊断难题提供一些可能的解决措施。     

Is the nasal optic disc sector important for morphometric glaucoma diagnosis?

BACKGROUND/AIM: Since the central retinal vessel trunk usually located in the nasal optic disc sector can render difficult the delineation of the neuroretinal rim and optic disc, the aim of this study was to evaluate whether the nasal region of the optic nerve head is important, or can be left out, for the morphometric glaucoma diagnosis. METHODS: The clinical observational study included 1337 patients with primary or secondary open angle glaucoma and 649 normal subjects. The glaucoma group was divided into 1187 patients with glaucomatous visual field defects ("perimetric glaucoma"), and into 150 patients with optic nerve head changes and normal visual fields ("preperimetric glaucoma"). Colour stereo optic disc photographs were morphometrically evaluated. RESULTS: Highest diagnostic power for the separation between the normal group and the perimetric glaucoma group, and for the differentiation between the normal group and the preperimetric glaucoma group, had the sum of inferotemporal rim area plus superotemporal rim area, the sum of inferotemporal rim area plus superotemporal rim area plus temporal rim area, and the inferotemporal rim area as single parameter. The lowest diagnostic precision had the nasal rim area as single parameter or in combination with rim measurements in other disc sectors. CONCLUSION: Excluding the nasal optic disc sector does not markedly decrease the diagnostic power of morphometric optic disc analysis in glaucoma diagnosis. It may have importance for an automated computerised morphometric detection of glaucomatous optic nerve damage.     

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。