准分子激光原位角膜磨镶术术后早期角膜空间变化

目的研究和分析近视性准分子激光原位角膜磨镶术(laser in stitu keratomileusis,LASIK)术后角膜空间变化规律。方法采用眼前节扫描系统(ORBSCANⅡ)观察48例(89眼)LASIK术前及术后1~3 d、第1周、第1个月、第3个月、第6个月的角膜前后表面高度和角膜最薄厚度的变化。结果术后角膜前表面高度迅速变平,到第1周时达最大量,此后至术后第6个月缓慢回升;术前等效球面镜度数和角膜基质床厚度与术后第3个月的角膜前表面高度变化呈直线正相关,切削比百分数(切削厚度占最薄角膜厚度比)与之呈直线负相关。LASIK术后角膜后表面即前凸,并达最大量,术后第1周时较快回落,此后至术后第6个月缓慢回落;术前等效球面镜度数、术前最薄角膜厚度、角膜基质床厚度与术后第3个月角膜后表面高度变化呈直线负相关,切削比百分数与之呈直线正相关。术后1~3 d角膜最薄,厚度最小,随着时间延长至术后第6个月均逐渐增厚,但速度逐渐减慢;术后1~3 d的实际角膜最薄厚度平均为(424±65.0)μm,比预计角膜最薄厚度平均值(463.9±42.1)μm低,差异有显著性(t=3.218,0.001相似文献   

准分子激光原位角膜磨镶术后角膜后表面变化及其影响因素

目的 探讨近视眼准分子激光原位角膜磨镶术(LASIK)术后角膜后表面变化规律及影响因素.方法 对72例(141只眼)行LASIK治疗的近视眼患者分别于术前、术后1周、1、3、6个月和12个月进行检查,分别记录视力、屈光度、眼压、角膜厚度、角膜后表面数据,将所得结果进行统计分析.结果 LASIK术前、术后各时期角膜后表面屈光度分别为(-6.60±0.23)、(-7.01±0.30)、(-6.97±0.29)、(-7.08±0.35)、(-7.03±0.29)D及(-7.01±0.31)D;术前与术后各时期比较差异均有统计学意义(F=48.675,P=0.000);术后3个月与术后1周、术后1个月比较差异有统计学意义(均P<0.05);术后角膜后表面屈光力(Y)与术前角膜后表面屈光力(X1)、术后角膜厚度(X2)、术后角膜后表面Diff值(X3)、术前角膜厚度(X4)、术前近视屈光度(X5)建立多元回归方程为Y=-0.915+0.911X1+0.004X2-5.541X3-0.003X4+0.021X5(F=88.041,P=0.000).LASIK术前、术后各时期角膜后表面Diff值分别为(0.032±0.007)、(0.057±0.014)、(0.056±0.015)、(0.060±0.016)、(0.056±0.017)及(0.059±0.048)mm,术前与术后各时期比较差异均有统计学意义(F=28.502,均P=0.000);但术后各时期之间比较差异均无统计学意义(均P>0.05);相关分析显示术后Diff值与术前眼压、近视屈光度和术后角膜后表面屈光力、角膜厚度等因素呈相关性(P均为0.000).结论 LASIK以直接改变角膜前表面屈光力来达到矫正近视目的 ,但也引起了角膜后表面变化,表现为术后角膜后表面前凸负性屈光力降低,这些变化以术后1周最明显,3个月后逐渐趋向稳定;其改变与角膜厚度、角膜切削深度和跟内压等因素相关.     

近视LASIK术后角膜后表面前凸的影响因素

目的:探讨准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后影响OrbscanⅡ中角膜后表面前凸量(后表面Diff值)的主要因素。方法:选取120例240眼近视患者眼行LASIK术,应用Orbscan-Ⅱ角膜地形图于术前和术后1,3,6,12mo分别检测术前和术后角膜后表面Diff值,统计分析影响术后Diff值的主要因素。结果:逐步回归方程分析,切削百分比和术前角膜后表面Diff值是术后各时期Diff值的影响因素,术前眼压也是影响术后1mo时Diff值的因素之一。结论:认为LASIK术前重视角膜后表面前凸量,并在保证手术效果的情况下控制切削百分比,同时在术后严密监测眼压,必要时降低患眼眼压,可以尽量避免术后角膜扩张、屈光回退等并发症的发生。     

传导性角膜成形术后角膜后表面的改变

目的:探讨传导性角膜成形术(conductive keratoplasty,CK)后角膜后表面的改变及其相关影响因素。方法:接受CK的老视患者30例(36眼),术前及术后1mo采用裂隙扫描角膜地形图系统检测角膜后表面的高度及屈光度差异,分析角膜后表面改变的相关影响因素。结果:CK术后角膜后表面平均前凸量为(32.7±20.4)μm,平均屈光度变化为(-0.64±0.40)D,和术前比较差异均有显著性意义。术前中央角膜厚度、眼压及拟矫正屈光度和角膜后表面前凸有关。结论:CK术后角膜后表面存在轻微的前凸。角膜较薄、眼压较高及拟矫正屈光度较大的受试眼术后角膜后表面前凸程度更大。     

准分子激光原位角膜磨镶术后眼压与角膜厚度及角膜屈光力的相关性

目的 :研究准分子激光原位角膜磨镶术后非接触式眼压计 (NCT)测量值的改变情况 ,以及其与术中角膜切削厚度及术后角膜屈光力改变值之间的相关性。方法 :随机选择接受LASIK手术的近视患者 1 77例 337眼 ,对术前、术后 1个月NCT测量值及角膜屈光力分别作配对t检验 ,并对术后眼压改变值与术中角膜切削厚度及术后角膜屈光力改变值分别作相关性分析 ,计算回归方程。结果 :①术后 1个月NCT测量值、角膜屈光力明显低于术前 ,差异有显著性 (P <0 .0 0 0 1 )。②术后眼压下降值 (Y)与术中角膜切削厚度 (X_1)呈正相关 (r =0 .2 4 1 ,P <0 .0 0 0 1 ,Y =2 .571 + 0 .0 2 5×X1)。③术后眼压下降值 (Y)与角膜屈光力下降值 (X2 )呈正相关(r =0 .2 6 1 ,P <0 .0 0 0 1 ,Y =2 .94 7+ 0 .2 85×X2 )。结论 :LASIK术后NCT测量值低于实际值 ,眼压下降与角膜厚度变薄及角膜屈光力下降有关。为避免LASIK术后青光眼的漏诊 ,应对NCT测量值进行矫正。     

准分子激光原位角膜磨镶术术后角膜后表面前凸和屈光力的变化

目的研究准分子激光原位角膜磨镶术(laser insitu keratomileusis,LASIK)术后角膜后表面前凸和屈光力的变化及影响二者变化的相关因素。方法对接受LASIK手术并有术后6个月随访记录、近视屈光度(等效球镜)为(-6.50±2.75)D的52例患者(76眼),于术前及术后第1个月、第2个月和第6个月分别行Orbscan-Ⅱ裂隙光扫描角膜地形图检查,测量角膜后表面前凸值、角膜后表面屈光力,观察其变化。用多元逐级回归法分析术前角膜最薄点厚度,以及眼内压、切削量与术后角膜后表面前凸的相关性。结果术后第1个月角膜后表面前凸值为(38.81±17.87)μm,术后第2个月为(35.61±13.60)μm,术后第6个月为(36.45±14.34)μm;3.0 mm直径角膜后表面屈光力均值术后第1个月为(-6.85±0.23)D,术后第2个月为(-6.83±0.28)D,术后第6个月为(-6.81±0.25)D;5.0 mm直径角膜后表面屈光力均值术后第1个月为(-6.34±0.24)D,术后第2个月为(-6.38±0.21)D,术后第6个月为(-6.39±0.25)D,上述观察值与术前比较差异有显著性(P<0.01),但术后第1个月同术后第2个月、第6个月比较差异无显著性。角膜后表面前凸值与角膜后表面屈光力线性相关(r=0.6,P<0.01)。多元逐级回归分析与术后角膜后表面前凸的变化有关系的变量为切削量(非标准系数B=0.405,P<0.01),角膜最薄点厚度(非标准系数B=-0.109,P<0.01),术前眼内压未进入最后回归方程。结论LASIK术后角膜后表面形态有显著性改变,角膜后表面呈锥形前凸,随术后时间延长角膜后表面形态趋于稳定;角膜厚度越薄、切削量越大则术后的角膜前凸值就越大。     

准分子激光原位角膜磨镶术后屈光度数回退的原因分析

目的　探讨准分子激光原位角膜磨镶术 (laserinsitukeratomileusis,LASIK)后屈光度数回退的原因。方法　将 2 5 0例 (40 8只眼 )近视患者 (- 6 0 0～ - 15 0 0D)按屈光度数分为A组 194只眼 (- 6 2 5～ - 10 0 0D)和B组 2 14只眼 (- 10 2 5～ - 15 0 0D)行LASIK ,记录术后视力、屈光度数、角膜厚度和角膜激光切削区直径 ,并进行统计学分析。术后平均随访时间 1年。结果　 (1)A组 :正常术眼 (术后屈光度数 <- 1 0 0D) 173只眼 (89 2 % ) ,术前平均角膜厚度为 (5 4 9 5± 31 5 ) μm ,术中平均激光切削直径为 (4 96± 0 35 )mm ,术后屈光度数为 +0 5 0～ - 0 75D ;回退术眼 (术后屈光度数≥ - 1 0 0D) 2 1只眼 (10 8% ) ,术前平均角膜厚度为 (5 4 7 5± 37 0 ) μm ,与正常术眼比较差异无显著意义 (P >0 0 5 ) ;术中平均激光切削直径为 (4 6 4± 0 4 1)mm ,与正常术眼比较差异有非常显著意义(P <0 0 1) ;术后平均屈光度数为 (- 1 33± 0 5 8)D。 (2 )B组 :正常术眼 136只眼 (6 3 5 % ) ,术前平均角膜厚度为 (5 6 0 9± 30 9) μm ,术中平均激光切削直径为 (4 5 1± 0 2 8)mm ,术后屈光度数为 +0 5 0～- 0 75D ;回退术眼 78只眼 (36 5 % ) ,术前平均角膜厚度为 (5 38 0± 31 0 ) μm ,     

近视眼准分子激光原位角膜磨镶术后屈光回退的相关因素分析

目的 探讨影响准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)治疗近视眼术后疗效的相关因素.方法 对72例(141眼)近视眼患者进行LASIK治疗.根据术前等效球镜屈光度分为3组:Ⅰ组<-6.00 D.计55眼:Ⅱ组-6.00～-8.75 D,计40眼:Ⅲ组≥-9.00 D,计46眼.分别记录术前和术后第1周、第1个月、第3个月的视力、屈光度、眼压、角膜厚度、角膜地形图检查所得的角膜后表面数据,分析术后裸眼视力与诸多因素之间的关系.结果 术后第3个月,裸眼视力4.4～5.2.平均4.98±0.12,三组间差异有显著统计学意义(P=0.000),有36眼视力<5.0且近视屈光度高于-1.00 D为屈光回退眼,105眼为正常眼.术后各阶段随访时发现,随着术后时间延长.角膜最薄处厚度均有不同程度增加,角膜后表面负性屈光度增大,角膜后表面Diff值增高,屈光回退组各指标不同阶段(术后第1周、第1个月、第3个月)比较,差异均有统计学意义(F分别为30.033、7.739、6.500,均P<0.01);但正常眼组各指标不同阶段比较,除角膜最薄厚度外,余差异均无统计学意义(角膜最薄厚度F=5.485,P<0.01:其余均P>0.05).设术后第3个月的裸眼视力为因变量(Y),X1为术前近视屈光度,X2为角膜切削比,X3为术后第3个月角膜后表面最高点Diff值,X4为术后第3个月和术后第1周角膜厚度差,X5为术后第3个月和术后第1周角膜后表面屈光度差,进行逐步回归分析,建立的多元回归方程为Y=5.09-0.034X1+1.785X2-2.216X3-0.002X4+0.081X5(F=21.474,P=0.000).结论 LASIK治疗近视是一种安全、有效的方法.但欲取得较好疗效,应考虑不同因素,如术前近视屈光度、角膜切削比、术后角膜增殖和术后角膜后表面改变等因素均有可能对LASIK的疗效造成影响,尤其是对高度或超高度近视,必要时采取部分矫正屈光力,以提高角膜切削比值,减少角膜的前突,将剩余屈光度用日后配戴低度眼镜的方法进行处理,避免出现术后并发症及屈光回退.     

影响LASIK术后角膜后表面稳定性的相关因素

目的：探讨影响准分子激光原位角膜磨镶术( laser in situ keratomileusis,LASIK )术后角膜后表面稳定性的相关因素。
　　方法：对来我院行LASIK手术的患者64例64眼分析术后6mo后表面变化与制瓣方式、角膜瓣厚度( flap thickness, FT)、切削厚度( ablation thickness,AT)、术后剩余基质厚度( postoperative residual corneal stroma thickness, RCST )、术前角膜最薄点厚度( preoperative thinnest corneal thickness,CT)、角膜瓣厚度/术前角膜最薄点厚度( flap thickness/ preoperative thinnest corneal thickness, FT/CT )、切削厚度/术前角膜最薄点厚度( ablation thickness/preoperative thinnest corneal thickness, AT/CT )、剩余基质厚度/术前角膜最薄点厚度( postoperative residual corneal stroma thickness /preoperative thinnest corneal thickness, RCST/CT)、术前角膜地形图(前表面高度、后表面高度、后表面diff值)和术前眼压的相关性。
　　结果：本研究表明手术前后角膜后表面diff差值与屈光度(r=0.419,P=0.014),AT(r=0.394,P=0.023),AT/CT(r=0.501,P=0.004),术前角膜后表面diff值(r=0.501,P=0.004),RCST(r=-0.385,P=0.033)和RCST/CT(r=-0.401, P=0.025)相关。手术前后角膜后表面高度差值与屈光度(r=0.520,P=0.002),AT(r=0.504,P=0.003),AT/CT(r=0.442,P=0.013),角膜后表面diff值(r=0.624,P=0.000)和RCST/CT(r=-0.394,P=0.028)相关。
　　结论：AT,RCST,AT/CT,RCST/CT和术前角膜地形图后表面diff值应作为预测术后角膜后表面稳定性的关键性指标,但具体安全限度值有待进一步研究。     

角膜厚度、眼压和屈光度对LASIK治疗近视疗效的影响

目的　了解角膜厚度、眼压、术前屈光度及性别对 L ASIK治疗中高度近视疗效的影响。方法　将 2 98例 (5 90只眼 )近视患者 ,根据术前角膜中央厚度 (CT)与术前眼压 (IOP)的比值进行分组 ,观察术后视力与角膜厚度、眼压、屈光度及性别之间的关系。结果　近视眼屈光度数高低与术前角膜中心厚度无统计学相关 ;角膜中心厚度男、女性患者基本接近 ,差异无统计学意义 ;术前角膜厚度与眼压比值 (CT/ IOP)小于 30 ,术后视力较差。角膜厚度与非接触式眼压进行相关分析 ,为中度相关 ,相关系数 r =0 .36 6 4 ,F值 =31.4 9,P <0 .0 0 0 1,相关具有高度统计学意义 ;术后视力与术前的屈光度存在负相关关系 ,Y=1.4 772 - 0 .0 6 13X(屈光度 )。结论　矫正高度或超高度近视 ,应适度控制激光切削深度和切削量 ,必要时采取部分矫正屈光力的方法 ,剩余屈光度日后配戴低度眼镜 ,以确保手术安全 ,避免出现术后并发症及屈光回退     

Follow-up studies in pattern VECP in demyelinating diseases in children

Spectral sensitivity functions and the transient decrease of sensitivity to short wavelengths after the offset of yellow light (transient tritanopia) were measured by increment threshold techniques in patients suffering from hereditary macular degenerations. Color vision defects were determined by arrangement tests and the anomaloscope. Central areolar choroidal dystrophy was found to produce a mild protan defect and to reduce foveal spectral sensitivity throughout the visible spectrum by a factor of 100; it also abolishes transient tritanopia. Electroretinogram (ERG) was normal, electrooculogram (EOG) subnormal. Stargardt's disease, despite numerous fluorescent macular spots, does not abolish transient tritanopia nor does it reduce spectral sensitivity, although scotopic matches were performed on the Nagel anomaloscope. Only in severe, advanced cases was transient tritanopia reduced and spectral sensitivity found to follow the absorption spectrum of rods. Routine ERGs and EOGs were normal. Vitelliform macular degeneration, despite the ophthalmoscopically pronounced dystrophic macula, produced only very small changes in spectral sensitivity and transient tritanopia, although a widened matching range on the Nagel anomaloscope and electrophysiological abnormalities were found. Apparently damage of the retinal circuit which connects long and short wavelength-sensitive cones, caused by hereditary conditions, is different from that caused by retinotoxic drugs.     

p53 expression in pterygium in two climatic regions in Turkey

Purpose:

To assess accumulation of p53 protein in samples of primary pterygium from people living in two different climatic regions in Turkey.

Materials and Methods:

Group 1 included 101 pterygium specimens from people in Adana located in southern Turkey. Group 2 included 39 pterygium specimens from people in Ankara, located in the middle of Turkey. Climatic conditions throughout the year are sunnier and warmer in Adana than they are in Ankara. The control group (Group 3) included 30 specimens of conjunctiva that had been excised during cataract surgery from 30 patients without pterygium. The pterygial specimens and control conjunctiva were studied by immunohistochemistry using antibodies against p53 protein. Pearson''s chi-square test was used to compare the p53 immunoreactivity.

Results:

The p53 immunoreactivity in Groups 1 and 2 was greater than it was in the control group (P<0.001). There were no differences in p53 immunoreactivity between Groups 1 and 2 (P= 0.060).

Conclusion:

The p53 immunoreactivity was not correlated with ultraviolet irradiation exposure. The p53 immunoreactivity in our pterygium specimens suggests that pterygium could be a result of uncontrolled cell proliferation.     

Changes in Bruch's membrane in experimental hypercholesteremia in rats

PURPOSE: We investigated the effect of high cholesterol diet for the aging changes in Bruch's membrane of rats. METHODS: After feeding a 4% cholesterol diet for 15 weeks to three young rats 3 months old and four aged rats 23 months old, we observed the morphological changes of Bruch's membrane by electron microscopy, and made a comparison with rats fed an ordinary diet. RESULTS: In one young rat fed a high-cholesterol diet, the endothelial basement membrane of the choriocapillaris formed multiple folds separated from the plasma membrane of the endothelium and showed lamellar thickening and crack in some areas. The elastic fiber layer in Bruch's membrane disappeared partly and some new microfibrils appeared. In one aged rat fed a high-cholesterol diet, the endothelial basement membrane of the choriocapillaris showed more lamellar thickening with lumps in some parts. Compared with rats fed an ordinary diet, rats fed a high-cholesterol diet showed thickening of the basement membrane and the changes were more severe. CONCLUSIONS: Our data indicated that high-cholesterol diet might promote age-related changes of Bruch's membrane.     

Trends in Patterns of Anterior Uveitis in a Tertiary Institution in Singapore

Purpose: To report the trends in etiology of patients with anterior uveitis (AU) in Singapore over 6 years.

Methods: A retrospective review of the clinical records of all new patients who presented with anterior uveitis to the uveitis subspecialty clinic from 2005 to 2010 at Tan Tock Seng Hospital, Singapore.

Results: There were 552 new cases of AU. This comprised 59.5% of a total of 928 new patients diagnosed with uveitis from 2005 to 2010. The mean age was 48.0?±?17.2 years. There was a male predominance (62.5%), with a male:female ratio of 1.7:1. The majority were of Chinese ethnicity (69%), followed by Malays (13.2%). Most cases were unilateral (79.5%) and idiopathic (50.4%). Common etiological causes included Fuchs heterochromic iridocyclitis (FHI) (5.6%), ankylosing spondylitis (AS)-related AU (5.1%), herpes simplex virus (HSV) (4.7%), and herpes zoster virus (HZV) (4.5%). There were increasing trends in AS-related AU from 3.2% in 2008 to 6.5% in 2010, and psoriasis-associated AU from 1.7% in 2005 to 4.0% in 2008. There were decreasing trends in the incidence of FHI from 10.6% in 2006 to 4.7% in 2009. No change in incidence of viral etiologies was noted, but cytomegalovirus-related immune-recovery uveitis (IRU) comprised 7.4%. IRU showed an increasing trend from 1.7% in 2005 to 11.9% in 2007, then decreased to 3.3% in 2010. Using the Pearson chi-square test, there was no statistically significant association between ethnicities (Chinese, Malay, Indian) comparing infectious and noninfectious cases (p?=?0.788), idiopathic and nonidiopathic cases (p?=?0.170), or between the various etiologies of uveitis (p?=?0.168).

Conclusions: AU was the predominant form of uveitis seen at our centers. Infectious etiologies (18.5%) are the most common among nonidiopathic cases, with herpes viruses (9.2%) being most prevalent. Despite increased use of polymerase chain reaction (PCR) in the detection of microbial and viral DNA, there was no overall increase in detection of infectious causes for uveitis. The changes in CMV-related immune recovery uveitis from 2005 to 2010 could reflect a change in HIV management in Singapore.     

Orthokeratology practice in children in a university clinic in Hong Kong*

Purposes: The aim of this study was to analyse clinical data of children undergoing orthokeratology (ortho‐k) and to investigate patients’/parents’ perspective on ortho‐k via telephone interviews. Methods: Clinical records of children undergoing ortho‐k from a university optometry clinic were reviewed and the effects of ortho‐k on refraction, vision and cornea were investigated. A telephone interview was conducted to solicit patients’/parents’ perspective of the treatment. Results: One hundred and eight files were reviewed. Median age of the children was nine years (range six to 15); mean (±SD) pre‐treatment refractive sphere was ‐3.56 ± 1.49 D and the median refractive cylinder was ‐0.50 D (range zero to ‐4.25 D). Significant refractive spherical reduction (58 per cent), improvement in unaided vision and corneal topographical changes were noted after only one night of wear. No significant change in astigmatism was found. Corneal staining was the most commonly observed complication with ortho‐k and more than 80 per cent of patients were advised to apply ocular lubricants to loosen the lens before lens removal. Ortho‐k was mainly undertaken for myopic control and about 90 per cent of the respondents reported good/very good unaided vision after ortho‐k and ranked the treatment as satisfactory or very good. Lens binding and ocular discharge were the most frequently reported problems during the treatment. Conclusion: Under close monitoring, overnight ortho‐k is effective and safe for reducing low to moderate myopia and the treatment is well accepted by the children.     

内毒素诱导的大鼠葡萄膜炎的巨噬细胞中Toll样受体4的表达

目的 探讨在内毒素诱导的Wistar大鼠葡萄膜炎中Toll样受体4(TLR4)阳性细胞与虹膜组织中巨噬细胞的动态变化和分布.方法 实验研究.Wistar大鼠50只,用随机数字法随机分为5组,每组10只,分别为正常对照(0 h)组、6 h组、12 h组、24 h组及48 h组.除0 h组外其余各组均足垫部注射霍乱弧菌内毒素200μg,注射后于裂隙灯显微镜下观察双眼前节炎症反应变化.按实验分组于0、6、12、24、48 h处死大鼠.取虹膜一睫状体及脉络膜组织.通过葡萄膜铺片免疫组织化学方法检测TLR4和巨噬细胞的标记CD163的表达.人工计数虹膜中TLR4~+与CD163~+的细胞并计算细胞密度,计算圆形和多形性的CD163~+细胞占所有CD163~+细胞的百分比.进一步采用免疫荧光双标记检测TLR4和CD163共表达的情况.通过单因素方差分析分别对大鼠虹膜内阳性细胞密度以及圆形、多形性CD163~+细胞的百分比进行统计学检验.结果 正常大鼠虹膜睫状体组织不表达TLR4.6 h组有2只大鼠虹膜内可见少量TLR4~+细胞,12～48 h组所有大鼠虹膜内TLR4~+细胞明显增多(F=167.2,P＜0.001),虹膜内TLR4~+细胞密度分别为(506.1±39.5)个/mm~2(12 h组)、(492.3±54.5)个/mm~2(24 h组)及(663.8±150.2)个/mm~2 (48 h组).在注射LPS后12～48 h期间TLR4~+细胞形态无明显变化.0～48 h组大鼠虹膜内均有CD163~+细胞,0 h组圆形和多形性CD163~+细胞百分比为13%,12～48 h组其百分比约为80%,且圆形细胞主要位于虹膜基质层.免疫荧光双标记可见TLR4和CD163的共表达,TLR4位于细胞膜,CD163位于细胞质.5组大鼠脉络膜内均未见TLR4表达.结论 内毒素诱导的大鼠葡萄膜炎中虹膜内TLR4表达增高,部分虹膜固有巨噬细胞表达TLR4.TLR4可能在葡萄膜炎的发生发展中起一定作用.     

弱视眼底光学相干断层扫描的研究进展

弱视是由于视觉发育关键期内各种异常的视觉经验导致单眼或双眼最佳矫正远视力低于正常同龄儿童,而眼部无明显器质性病变。目前普遍观点认为,弱视的发病机理主要源于视皮层。近年来,光学相干断层扫描（OCT）作为一种先进的活体成像技术,促进了对视网膜形态结构的大量研究,同时也被应用到弱视的研究领域。陆续有不同的研究人员利用OCT发现弱视患者眼底视网膜、脉络膜等眼部结构存在改变。笔者将对弱视眼底OCT的研究进展做一综述。     

实验性糖尿病视网膜微血管病变的病理研究

目的：观察糖尿病视网膜病变（diabetic retinopathy,DR）的组织学改变。方法：应用光镜、免疫组织化学、电镜及组织化学电镜等技术,研究在不同时间点Spregue-Dawley(SD)大鼠视网膜毛细血管基底膜中的Ⅳ型胶原蛋白及层黏蛋白和视网膜毛细胞血管基底膜的厚度,以及其负电荷位点数目的变化。结果：随着糖尿病病程的发展,视网膜毛细血管基底膜下不断增厚伴有Ⅳ型胶原蛋白及层黏蛋白的增加,同时负电荷位点数目减少。结论：视网膜毛细血管基底膜增厚,Ⅳ型胶原蛋白及层黏蛋白的增加,负电荷位点数目减少可能是导致DR渗出性病变的病理基础。