全视网膜光凝术对增生性糖尿病视网膜病变患者黄斑区视网膜功能的影响

目的　观察全视网膜光凝术对增生性糖尿病视网膜病变（ｐｒｏｌｉｆｅｒａｔｉｖｅｄｉａｂｅｔｉｃｒｅｔｉｎｏｐａｔｈｙ,ＰＤＲ）患者黄斑区视网膜功能的影响。方法　选取２０１１年１月至２０１３年１２月我院收治的６０例（７２眼）ＰＤＲ患者作为观察组,同时选取６０例（６０眼）正常志愿者作为对照组。观察组患者均应用全视网膜光凝术进行治疗。两组均行裂隙灯、验光、眼压、眼底等常规眼部检查,利用光学相干断层扫描（ｏｐｔｉｃａｌｃｏｈｅｒｅｎｃｅｔｏｍｏｇｒａｐｈｙ,ＯＣＴ）检查黄斑区视网膜厚度,同时利用多焦视网膜电图（ｍｕｌｔｉｆｏｃａｌｅｌｅｃｔｒｏｒｅｔｉ-ｎｏｇｒａｍ,ｍｆ-ＥＲＧ）检查Ｐ１波、Ｎ１波５环的振幅密度及潜伏期等。结果　观察组患眼术前、术后黄斑中心凹视网膜厚度分别为（３４９．３±１１８．９）μｍ和（２６２．２±２８．２）μｍ,差异有统计学意义（Ｐ＜０．０５）;对照组黄斑中心凹视网膜厚度为（１３６．４±１７．８）μｍ,均显著低于观察组患眼手术前后黄斑中心凹视网膜厚度,差异均有统计学意义（均为Ｐ＜０.０５）。观察组患眼的１环、２环的术后Ｐ１波振幅密度较术前显著提高,差异均有统计学意义（均为Ｐ＜０．０５）,而３环、４环、５环较术前显著降低,差异均有统计学意义（均为Ｐ＜０．０５）。观察组术后Ｐ１波潜伏期较术前均有一定程度的下降,差异均有统计学意义（均为Ｐ＜０．０５）。与对照组比较,观察组术后１环、２环的Ｐ１波潜伏期差异均有统计学意义（均为Ｐ＜０．０５）;３环、４环、５环差异均无统计学意义（均为Ｐ＞０．０５）。观察组术后１环、２环的Ｎ１波振幅较术前显著提高,差异均有统计学意义（均为Ｐ＜０．０５）;术后３环、４环、５环较术前显著降低,差异均有统计学意义（均为Ｐ＜０．０５）。观察组患眼术后３环的Ｎ１波潜伏期与术前比较,差异无统计学意义（Ｐ＞０.０５）,术后１环、２环、４环、５环的Ｎ１波潜伏期均显著低于术前,差异均有统计学意义（均为Ｐ＜０．０５）。观察组术前和术后的Ｎ１波潜伏期均显著低于对照组,差异均有统计学意义（均为Ｐ＜０．０５）。结论　全视网膜光凝术治疗ＰＤＲ患者可显著改善视网膜的感光和传导功能,降低黄斑中心凹视网膜厚度,从而达到部分改善视力的目的。     

中心性浆液性脉络膜视网膜病变PERG和PVEP的研究

目的：观察中心性浆液性脉络膜视网膜病变（中浆）的图形视网膜电图（ＰＥＲＧ）和图形视诱发电位（ＰＶＥＰ）的表现。方法：检查９２例（１２０眼）正常人、５１例（５２眼）中浆患者的ＰＥＲＧ和ＰＶＥＰ。结果；患眼的ＰＶＥＰ的Ｐ１００潜伏期和ＰＥＲＧｂ波潜伏期延长，ＰＶＥＰ的Ｐ１００振幅ＰＥＲＧ的ｂ波振幅降低，中浆病情重，视力下降明显者，ＰＶＥＰ和ＰＥＲＧ的潜伏期改变最明显。结果：中浆患者的ＰＥＲＧ和ＰＶＥＰ     

视网膜色素变性黄斑区视网膜FD-OCT及mfERG观察

目的　利用频域光学相干断层扫描（ｆｒｅｑｕｅｎｃｙｄｏｍａｉｎｏｐｔｉｃａｌｃｏｈｅｒｅｎｃｅｔｏｍｏｇｒａｐｈｙ,ＦＤ-ＯＣＴ）及多焦视网膜电图（ｍｕｌｔｉ-ｆｏｃａｌｅｌｅｃｔｒｏｒｅｔｉｎｏｒｇｒａｍ,ｍｆＥＲＧ）观察视网膜色素变性（ｒｅｔｉｎｉｔｉｓｐｉｇｍｅｎｔｏｓａ,ＲＰ）患者黄斑区视网膜图像特征。方法　选取临床确诊的ＲＰ患者３０例（３０眼）作为ＲＰ组,年龄相匹配的健康人３０人（３０眼）作为对照组。采用ＦＤ-ＯＣＴＲＴＶｕｅ的Ｅ-ＭＭ５扫描模式对５ｍｍ×５ｍｍ范围的黄斑中心视网膜进行检测,获取视网膜厚度及内、外层视网膜容积,同时采用ＲＥＴＩｐｏｒｔ视觉电生理系统测量ｍｆＥＲＧ,对两组测量结果进行比较分析。结果　ＲＰ组视网膜黄斑中心凹厚度为（１４０．８０±１９．２５）μｍ,对照组为（１６５．９１±１４．３９）μｍ,差异无统计学意义（Ｐ＞０．０５）。ＲＰ组黄斑区外层视网膜体积为（３．６１±０．１８）ｍｍ３,低于对照组（４．５９±０．１１）ｍｍ３,差异有显著统计学意义（Ｐ＜０．００１）。ＲＰ组黄斑区内层视网膜体积为（２．２８±０．１０）ｍｍ３,对照组为（２．３０±０．１０）ｍｍ３,两组比较差异无统计学意义（Ｐ＞０．０５）。ＲＰ组ｍｆＥＲＧ各环Ｎ１、Ｐ１波反应密度值均低于对照组,且差异均有统计学意义（均为Ｐ＜０．０５）。ＲＰ组Ｎ１、Ｐ１波３～５环的潜伏期较对照组显著延长,差异均有统计学意义（均为Ｐ＜０．０５）。结论　ＦＤ-ＯＣＴ和ｍｆＥＲＧ相结合可有效评价ＲＰ患者视网膜功能及形态特点。     

结晶样视网膜变性的视觉电生理改变探讨

目的探讨结晶样视网膜变性的视觉电生理改变。方法采用眼电图（ＥＯＧ）和视网膜电图（ＥＲＧ）检测１４例２８眼结晶样视网膜变性患者（病例组）和１５例３０眼正常人（对照组）、观察指标：（１）ＥＯＧ的基值电位（ＢＶＰ）、暗谷电位（ＤＴＰ）、暗谷时间（ＤＴＴ）、光峰电位（ＬＰＰ）、光峰时间（ＬＰＴ）、ＱＡｒ－ｄｅｎ、ＱＧｌｉｅｍ、（２）暗适应和明视ＥＲＧａ、ｂ波振幅、峰时值。采用ｔ检验对上述各项指标做两组间比较分析。结果病例组ＥＯＧ的ＢＶＰ、ＤＴＰ、ＬＰＰ、ＱＡｒｄｅｎＱＧｌｉｅｍ均较对照组明显降低,峰两组间有极显著性差异（Ｐ＜０．０１）;而ＥＯＧ的ＤＴＴ、ＬＰＴ与对照组比无明显改变,两组间无显著性差异（Ｐ＞０．０５）。病例组暗适应和明视ＥＲＧａ、ｂ波振幅、峰时值较对照组均有明显改变,两组间有极显著性差异（Ｐ＜０．０１）;但在２例早期患者中,其ＥＲＧａ、ｂ波振幅、峰时值均在正常范围。结论ＥＯＧ、ＥＲＧ作为客观定量的视功能检查方法,可为结晶样视网膜变性的视网膜功能损害程度提供客观指标。对结晶样视网膜变性早期患者ＥＯＧ可能较ＥＲＧ更具诊断价值。     

中心性浆液性脉络膜视网膜病变PERG和PVEP的研究

目的：观察中心性浆液性脉络膜视网膜病变（中浆）的图形视网膜电图（ＰＥＲＧ）和图形视诱发电位（ＰＶＥＰ）的表现。方法：检查９２例（１２０眼）正常人、５１例（５２眼）中浆患者的ＰＥＲＧ和ＰＶＥＰ。结果：患眼的ＰＶＥＰ的Ｐ１００潜伏期和ＰＥＲＧｂ波潜伏期延长，ＰＶＥＰ的Ｐ１００振幅和ＰＥＲＧ的ｂ波振幅降低，中浆病情重、视力下降明显者，ＰＶＥＰ和ＰＥＲＧ的潜伏期均延长明显，波幅亦下降明显。四个观察指标中，以Ｐ１００潜伏期改变最明显。结论：中浆患者的ＰＥＲＧ和ＰＶＥＰ均有改变，有时较视力更敏锐，可客观反映中浆患者的视功能，检查以ＰＶＥＰ更为简便有效。     

视网膜色素变性的ERGs观察

目的：为研究视网膜色素变性的视网膜电图（ＥＲＧｓ）,测定了７５例１５０眼视网膜色素变性病人的ＥＲＧｓ,分析了其ｂ波振幅情况。方法：用视觉电生理仪测量ＥＲＧｓ的ｂ波振幅。分析从５个月到７０岁的７５例１５０多膜色素变性病人的ＥＲＧｓ的ｂ波振幅情况。结果：（１）ｂ波振重度降低或记录不到波形者１３０眼,占８７％,平均年龄２５岁,其最好视力达１．５,最低右无光感。（２）ｂ波振幅轻度或中度降低者１０例２０眼,     

正常眼和老年黄斑变性眼的局部视网膜电图

以全视野亮背景及４５′视角的红色闪光作刺激，采用带中孔的角膜接触镜电极，记录了局部视网膜电图。测得２２只正常眼的黄斑中心对盲点区的局部ＥＲＧ振幅之比值为３．５４±１．３５，而３１只老年黄斑变性眼的比值是１．３９±０．５４，两者差异显著（Ｐ＜０．０１），两组全视野明适应ＥＲＧ间无意义，表明此法建立的局部ＥＲＧ记录技术对早期老年黄斑变性病人具有一定诊断价值。     

电针对透镜诱导性近视豚鼠闪光视网膜电图的影响

目的　探讨电针对透镜诱导性近视豚鼠闪光视网膜电图（ｅｌｅｃｔｒｏｒｅｔｉｎｏｇｒａｍ,ＥＲＧ）的影响。方法　２４只３周龄健康三色短毛豚鼠随机分为透镜诱导组（１２只）与透镜诱导＋电针组（１２只）。两组豚鼠右眼戴－１０Ｄ透镜,左眼不戴镜作为自身对照。透镜诱导＋电针组在戴镜的同时,电针刺激豚鼠两侧合谷穴与太阳穴。４周后测量２组屈光度、眼轴长度及ＥＲＧ波形的变化。结果　４周后,与自身对照眼比较,透镜诱导眼近视屈光度增加（Ｐ＜０．０１）,眼轴延长（Ｐ＜０．０１）;同时其暗适应振荡电位的ＯＳ２波振幅及总振幅下降（均为Ｐ＜０．０１）,暗适应最大混合反应、明适应视锥细胞反应的ｂ波振幅下降（均为Ｐ＜０.０１）。电针干预后,透镜诱导眼的屈光度和眼轴长度没有变化（Ｐ＞０．０５）;但与透镜诱导组右眼相比,透镜诱导＋电针组透镜诱导眼暗适应振荡电位的ＯＳ２波振幅及总振幅,暗适应最大混合反应、明适应视锥细胞反应的ｂ波振幅均增高（均为Ｐ＜０．０５）,达到与其自身对照眼相似的水平（均为Ｐ＞０．０５）。结论　电针刺激合谷穴与太阳穴影响透镜诱导性近视豚鼠ＥＲＧ,可使其恢复至正常水平。     

黄斑部病变的局部视网膜电图和图形视觉诱发电位

目的观察黄斑病变局部视网膜电图（ｌｏｃａｌｅｌｅｃｔｒｏｒｅｔｉｎｏｇｒａｍ，ＬＥＲＧ）和图形视觉诱发电位（ｐａｔｅｒｎｖｉｓｕａｌｅｖｏｋｅｄｐｏｔｅｎｔｉａｌ，ＰＶＥＰ）的变化，评价二者的临床应用价值。方法对２７例（５４只眼）正常人进行黄斑部视角５°、１０°和１５°ＬＥＲＧ测定，并对２５例（３５只眼）黄斑病变患者进行ＬＥＲＧ和ＰＶＥＰ的测定。结果黄斑病变患者５°、１０°和１５°ＬＥＲＧ的ａ、ｂ波振幅均值较正常对照组均有显著性降低（Ｐ＜０．０１），３６．５′、７３′及１４６′ＰＶＥＰ的Ｐ１波潜伏期及振幅均值分别较正常对照组明显延长和降低（Ｐ＜０．０１）。在ＬＥＲＧ（１５°）与ＰＶＥＰ（１４．８°×１９．０°）刺激野相近的条件下，黄斑病变ＬＥＲＧ异常率为６２．２％、ＰＶＥＰ的异常率分别为４８．５％（１４６′）、５４．５％（７３′）及４８．５％（３６．５′），ＬＥＲＧ和ＰＶＥＰ的异常率差异均无显著性（Ｐ＞０．０５）。结论ＬＥＲＧ与ＰＶＥＰ的异常率相接近。由于ＬＥＲＧ不受视路功能的影响，故认为此项检查是一种较有效和较直接的黄斑功能测定方法     

多焦视网膜电图在糖尿病视网膜病变不同病期诊断的应用

目的：评价多焦视网膜电图（ＭＥＲＧ）在糖尿病性视网膜病变（ＤＲ）不同期诊断的应用价值。方法：对２４名（３５眼）正常人及６３名（９６眼）糖尿病患者分别进行眼科常规检查、眼压测定、眼底荧光血管造影（ＦＦＡ）、Ｏｃｔｏｐｕｓ视野及ＭＥＲＧ检测,并对ＭＥＲＧ与视野进行相关性分析,对比ＭＥＲＧ与其他视网膜功能检查方法的异常检出率。结果：ＭＥＲＧ总反应波的Ｐ１波反应密度在临床未见ＤＲ（ＮＤＲ）的糖尿病患者低于     

Nondetectable S-cone electroretinogram in a patient with crystalline retinopathy

We examined cone and rod electroretinograms to ganzfeld stimuli in a patient with crystalline retinopathy. The 54-year-old man complained of night blindness, blurred vision, and metamorphopsia in both eyes. His visual acuity was 10/200 in the right eye and 10/20 in the left eye; his subjective dark-adaptation threshold was elevated 1 log unit, and he made one tritan error on the Farnsworth Panel D-15. Specular microscopic examinations revealed tiny crystalline deposits in the limbal cornea bilaterally. Ophthalmoscopically, crystalline deposits were found in the posterior fundi. His light-adapted cone electroretinograms to white stimuli were diminished (about 30% of those of normal controls), with normal implicit times. His darkadapted rod electroretinogram amplitudes were 10% of those of normal controls. The S-cone electroretinogram was not detectable to different spectral stimuli with strong white background, while the L-M-cone responses appeared normal in waveforms with reduced amplitude. These ERG results indicated that the patient's S-cone system is more highly impaired than the L-M-cone system, supporting the psychophysical evidence that the S-cone system is more vulnerable than other cone systems in retinal diseases.     

Standard for pattern electroretinography

The pattern electroretinogram (PERG) is a retinal response evoked by viewing an alternating checkerboard or grating. It receives clinical and research attention because it can provide information about inner retinal cells and the macula. However, clinicians may have trouble choosing between different techniques for recording the PERG that have been described in the literature. The International Society for Clinical Electrophysiology of Vision has prepared a standard for a basic PERG recording procedure to aid new users in obtaining reliable responses and to encourage more uniformity among existing users.     

The wide-angle pattern electroretinogram

Pattern electroretinograms (PERGs) were recorded from two normal human subjects in response to various spatial frequencies and stimulus areas. The maximum stimulus area was 75° × 86° which was achieved by using a standard TV monitor and a reduced viewing distance. The amplitude of the PERG increased with area in an approximately logarithmic fashion over the range investigated. The explanation relates to non-linearities of the stimulus, the retinal image and neural processing. The wide-angle PERG may be useful in the assessment of retinal diseases affecting the mid-peripheral inner retina, such as diabetic retinopathy.     

The electrical response of the human eye to patterned stimuli: Clinical observations

Following the first recording of electroretinographic responses in man to a barred pattern by Riggs and associates (1964) in normal and by Lawwill (1973, 1974) in clinical cases, the first striking observation of a complete loss of pattern electroretinogram (PERG) after injurious section of the optic nerve by Groneberg & Teping (1980) has led to the conclusion that the PERG originates from proximal retinal structures different from those responsible for the luminance electroretinogram (LERG). Typical changes of the PERG are seen during branch occlusion of the central retinal artery and vein. In ocular hypertension without visual field loss and glaucoma-related papillary changes the PERG is decreased at intraocular pressures above 26 mm Hg. In cases of primary glaucoma with regulated intraocular tension and without using miotics the amplitude of the PERG reflects the damage to the inner retinal layers. This favorably compares with the P100 latencies of the visual evoked cortical potential (VECP) which in primary glaucoma were partly within, partly outside the normal range. Other retinal diseases showing amplitude changes in the PERG are primary macular dystrophy, diabetic retinopathy, and the acute stage of optic neuritis. In all these cases the Ganzfeld LERG may be normal or nearly normal, whereas the PERG undergoes typical changes. On the contrary a highly preserved PERG can be recorded in cases of retinitis pigmentosa where the electrooculogram light rise and the LERG are already missing. In light of these findings the recording of PERG constitutes a new promising method of clinical electroretinography reflecting the activity of the hitherto omitted innermost retinal layers. It thereby contributes essentially to the location of disturbances within the visual system.     

The multifocal electroretinogram in X-linked juvenile retinoschisis

To measure and compare the multifocal electroretinography in normal control and X-linked juvenile retinoschisis, 13 cases (13 right eyes) of normal control and nine cases (17 eyes) of X-linked juvenile retinoschisis were measured with VERIS Science 4.0. Four cases (eight eyes) out of the nine retinoschisis cases were tested with Ganzfeld ERG at the same day. The results showed statistically significant difference of average response densities and latencies in six ring retinal regions between the normal control and retinoschisis. The trace array and 3-D topography of multifocal ERG showed multi-area amplitude decrease with absence or reduction of central peak amplitude in patients with retinoschisis. The P₁/N₁ ratio of multifocal ERG average response densities in six ring retinal regions was different from the b/a ratio of Ganzfeld ERG. The multifocal ERG and Ganzfeld ERG each had its advantage in the diagnosis of retinoschisis.     

Pattern electroretinogram can be more than the sum of local luminance responses

It is generally accepted that the pattern electroretinogram for very large spatial elements is the result of local luminance stimulation. Responses due to the luminance differences between elements may be assumed to be relatively unimportant because in the case of large elements only few retinal units are stimulated by gradients. With decreasing pattern element size one wonders to what extent the electroretinogram continues to be based on the local luminance stimulation. We investigated this question using 8 Hz checkerboard reversal and compared the pattern recordings with the recordings resulting from the same stimulus field modulated homogeneously (focal electroretinogram). A 100% modulated checkerboard at retinal level may be considerably less modulated because of imperfect optics of the eye. So the pattern electroretinogram should be compared with homogeneous field stimulation of correspondingly lower modulation depth. On the basis of the optical transfer properties of the eye we compared by subtracting the proper focal electroretinogram from the pattern electroretinogram. The difference response was virtually zero for check sizes larger than 120. For checks from 60 down the difference response was of the same order of magnitude as the adjusted focal recording. This difference response for eyes with normal optics is largest around 30; its wave form was found to be rather invariant with check size.     

Diabetes Exacerbates the Intraocular Pressure-Independent Retinal Ganglion Cells Degeneration in the DBA/2J Model of Glaucoma

PurposeGlaucoma is a multifactorial disease, causing retinal ganglion cells (RGCs) and optic nerve degeneration. The role of diabetes as a risk factor for glaucoma has been postulated but still not unequivocally demonstrated. The purpose of this study is to clarify the effect of diabetes in the early progression of glaucomatous RGC dysfunction preceding intraocular pressure (IOP) elevation, using the DBA/2J mouse (D2) model of glaucoma.MethodsD2 mice were injected with streptozotocin (STZ) obtaining a combined model of diabetes and glaucoma (D2 + STZ). D2 and D2 + STZ mice were monitored for weight, glycemia, and IOP from 3.5 to 6 months of age. In addition, the activity of RGC and outer retina were assessed using pattern electroretinogram (PERG) and flash electroretinogram (FERG), respectively. At the end point, RGC density and astrogliosis were evaluated in flat mounted retinas. In addition, Müller cell reactivity was evaluated in retinal cross-sections. Finally, the expression of inflammation and oxidative stress markers were analyzed.ResultsIOP was not influenced by time or diabetes. In contrast, RGC activity resulted progressively decreased in the D2 group independently from IOP elevation and outer retinal dysfunction. Diabetes exacerbated RGC dysfunction, which resulted independent from variation in IOP and outer retinal activity. Diabetic retinas displayed decreased RGC density and increased glial reactivity given by an increment in oxidative stress and inflammation.ConclusionsDiabetes can act as an IOP-independent risk factor for the early progression of glaucoma promoting oxidative stress and inflammation-mediated RGC dysfunction, glial reactivity, and cellular death.     

S-cone, L + M-cone, and pattern, electroretinograms in ocular hypertension and glaucoma

Silent substitution and selective adaptation techniques were used to obtain full field S-cone and L + M-cone electroretinograms from 18 patients with ocular hypertension (OHT), 9 with normotensive glaucoma (NTG), 18 with early primary open angle glaucoma (POAG) and 19 normal controls. Pattern electroretinograms were also recorded, using a reduced check size to increase the contribution of retinal ganglion cells. In the OHT and POAG groups, statistically significant reductions (P = 0.05-0.001) were observed in the amplitudes, most notably in the late negative waves of all three types of ERG compared to the controls. These are thought to reflect ganglion cell activity. The results imply a diffusely distributed loss of activity (20-35%) affecting many retinal pathways to a similar extent in OHT and early POAG, with an additional amount (<5%) in POAG corresponding approximately to the loss associated with local field defects. The electrophysiology indicated that virtually all cases of untreated OHT have greater retinal dysfunction than the least affected cases of POAG. The NTG group showed a different pattern of loss in that the PERG was markedly affected but the S-cone ERG was not significantly reduced.     

The point-spread function of the eye from 0° to 100° and the pattern electroretinogram

In studies on the pattern electroretinogram the quality of the retinal image is a major concern. The use of contact lens electrodes was rejected since a good pattern could not be recorded. This is believed to be due to blurring of the retinal image. As indicator of image quality the patient's visual acuity is often used. We wondered whether this is a sufficient criterion. The retinal image is the product of the whole optical point-spread function of the eye whereas visual acuity refers only to the central portion of this function. On the basis of existing reports it can be estimated that for the young normal eye the outer edges of this function (straylight) causes considerable loss of contrast. The strength of the straylight can be much greater in older eyes. We studied the relation between the point-spread function including straylight and the pattern electroretinogram in normal eyes and some pathological cases. The measurements proved to follow the calculated contrasts on the basis of a local luminance model, with the exception of enhancement (tuning) around 60 checksize for the young normal eye. Because of the considerable differences in straylight in an older population one has to take into account that loss of pattern electroretinogram can be suffered in patients with otherwise good visual acuity.