Long-term outcomes of drusenoid pigment epithelium detachment in intermediate AMD treated with 577 nm subthreshold micropulse laser: a preliminary clinical study

AIM: To evaluate the long-term anatomical and visual outcomes of drusenoid pigment epithelial detachment (D-PED) in intermediate age-related macular degeneration (AMD) eyes treated with 577 nm yellow subthreshold micropulse laser (SML). METHODS: In this retrospective study, 21 eyes of 16 patients with D-PED in intermediate AMD were consecutively included and assessed. All the eyes were treated with 577 nm SML in several sessions according to D-PED growth status. The logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA) were assessed at the initial visit and after treatment. Spectral-domain optical coherence tomography (SD-OCT) was performed to evaluate the D-PED lifecycle by volumetric calculations. Regression analysis was used to determine the breakpoint, growth, and collapse rate of the D-PED lesions. The progression to advanced AMD was also documented. RESULTS: All the eyes were treated with SML for 2.9±1.0 sessions. The mean follow-up period was 25.3±12.6mo. The BCVA was stable from the baseline to final visit. All the eyes were categorized into two groups according to the anatomical changes of the D-PED lesion: the collapse group (n=6, 28.6%) and non-collapse group (n=15, 71.4%). The change in logMAR BCVA did not differ significantly between the collapse group 0.00 (-0.31, 0.85) and non-collapse group 0.00 (0.00, 0.00; P=1). Regression analysis showed that the growth rate was significantly higher in the collapse group (0.090±0.095 mm3/mo) than in the non-collapse group (0.025±0.035 mm3/mo; P<0.001). One eye (4.8%) developed macular neovascularization at 11mo after SML treatment in the non-collapse group. Three eyes (14.3%) developed geographic atrophy (GA) in the collapse group. CONCLUSION: Compared to the natural course of D-PED reported by previous studies, our results preliminarily show that SML can alleviate visual loss and possibility of progression to advanced AMD in eyes with D-PED in intermediate AMD. A controlled clinical trial needs to further verify the benefit of the intervention.     

兔眼虹膜和视网膜色素上皮细胞移植的形态学观察

目的 比较有色兔虹膜色素上皮及视网膜色素上皮细胞在白兔视网膜下腔的生长状况。 方法 分离培养有色兔的IPE及RPE细胞。采用内路法在8只白兔16眼中进行了IPE和RPE细胞悬液的移植,其中左眼移植IPE细胞,右眼移植来自同一供体兔的RPE细胞。8只兔分别在2周(n=3)、4周(n=3)和6周(n=2)时处死。对眼球壁做光镜和电镜检查。 结果 IPE和RPE细胞在异体视网膜下腔存活,绝大多数贴附在Bruch’s膜上,并具有极性,细胞基底部有大量的皱褶,细胞顶部有一些微绒毛。6周时未见移植细胞周围有炎性细胞浸润。 结论 移植的IPE和RPE细胞可以在视网膜下腔存活,它们的形态均和原先RPE细胞类似。IPE细胞有望替代RPE细胞用于移植。     

Retinal pigment epithelium decompensation. I. Clinical features and natural course

We studied 97 eyes (73 patients) that showed a sharp contrast between the grossly normal appearance of the posterior pole by funduscopy and the fluorescein angiography findings of multiple patches of retinal pigment epithelium (RPE) transmission defect in the early transit, associated with focal areas of RPE staining in the late transit. The staining was located primarily at the superior edge of the RPE defect (63 eyes). The average age of the patients was 52.2 years at the time of diagnosis, and the ratio of men to women was 3.5 to 1. Ocular histories were unremarkable, except for 27 eyes with documented central serous retinopathy. Thirty-two consecutive eyes have been followed for an average of 3.9 years, and 30 of those eyes have shown visual deterioration.     

Macular dysplasia and pigmented paravenous retino-choroidal atrophy

Pigmented paravenous retino-choroidal atrophy (PPRCA) is a rare retinal disease characterized by bilateral patches of pigment and areas of chorioretinal atrophy distributed along the veins. The authors present a 21-year-old male with pigmented paravenous retinochoroidal atrophy and unilateral macular dysplasia. To their knowledge, this is the second reported case of macular involvement. They believe that such association is not occasional, but may be suggestive of a variable expressivity of the disease.     

兔眼视网膜铁锈症的实验观察

在光镜和电镜下观察了25只兔眼植入铁异物1～30天的视网膜变化。结果表明,邻近铁异物的局部视网膜2天即发生变性坏死,7～30天坏死的部分由视网膜色素上皮细胞(RPE)和胶质细胞填充,形成视网膜重度萎缩。在间接铁锈症的轻度萎缩性视网膜病变中,导致感光细胞形态学改变的重要原因,可能是RPE吞噬功能异常增高。观察了RPE转变为吞噬细胞,向玻璃体侧移行的过程。     

Rips of the retinal pigmentepithelium

A rip or rupture of the detached retinal pigment epithelium (RPE) with subsequent retraction of that layer is an often misdiagnosed affection of the posterior pole of the eye. The histologic appearance of this entity has to our knowledge not yet been published, but the fundus aspect and fluorescein angiography show that the focal absence of the pigmentepithelial layer is very likely. A rip is only seen in older age and it always appears in a detached RPE that often exists in combination with other features of a senile macular degeneration. Mostly the rip arises spontaneously but it may develop sometimes directly after laser coagulation of the detached RPE.     

Dissociation of rod and cone sensitivity by acute localized retinal pigment epithelium loss

Purpose: To assess the impact of acute retinal pigment epithelium (RPE) loss on photopic and scotopic sensitivity. Methods: A 68‐year‐old woman who had been followed for drusenoid RPE detachment in age‐related macular degeneration presented with an acute spontaneous retinal pigment epithelium tear. Three months later, she was seen for routine follow‐up and was examined by manual photopic and scotopic threshold perimetry (a static 0.46‐degree‐diameter 660 nm stimulus under photopic conditions; then, following 25 min of dark adaptation, a static 0.46‐degree‐diameter 532 nm stimulus under scotopic conditions). The stimuli were applied over the RPE defect and at reference points of similar eccentricity in the opposite vertical haemifield of the same eye where the RPE remained present. Results: Acute RPE loss was associated with only a marginal reduction of photopic sensitivity (?1.5 dB) but a pronounced loss of scotopic sensitivity (?19.5 dB). Conclusion: Our observations show that RPE is essential for scotopic but not for photopic retinal function, supporting the theory that cone photopigment regeneration occurs within the human neurosensory retina independently of the RPE.     

A Model for the Formation of Ring Mitochondria in Retinal Pigment Epithelium

Purpose:To investigate the mechanism and sequence of formation of ring-shaped mitochondria in retinal pigment epithelial cells of a chick model of gyrate atrophy.Methods: Electron microscopic analysis of the ultrastructure of retinal pigment epithelial (RPE) mitochondria was carried out in chicks injected intravitreally with formoguanamine regularly (every 4 days) over the first 2 weeks or 4 weeks post-hatching. Formoguanamine is a triazine drug which induces hyperor-nithinemic symptoms in the chick eye similar to those seen in human gyrate atrophy.Results: A large population of irregularly shaped mitochondria was observed in the RPE of both peripheral and central retina. They showed extensive morphological changes. At 2 wk,the mitochondria appeared enlarged and abnormal in shape with vacuolisation, partial loss of their double membrane and reduced mitochon-drial cristae. By 4 wk, the mitochondria had assumed a rounder, almost circular profile,many with central holes,so-called ring mitochondria.Conclusi     

兔虹膜和视网膜色素上皮细胞的体外培养比较

目的 观察比较有色素兔虹膜色素上皮(IPE)及视网膜色素上皮(RPE)细胞的体外生长状况。方法 采用酶消化法及酶辅助机械分离法分别分离IPE和RPE细胞。观察培养的两种细胞的生长状况，并对其进行免疫组化鉴定。结果 原代IPE及RPE细胞大多呈圆形或六边形，细胞内充满了黑色素颗粒。随着传代的增加，呈梭形或纤维细胞样生长的细胞增多，细胞中的色素颗粒也逐渐减少。细胞角蛋白免疫组化染色显示IPE及RPE细胞绝大多数呈棕黄色阳性反应。Desmin兔疫组化染色显示IPE细胞中阳性细胞约占5％。结论 分离培养的IPE和RPE细胞纯度很高。IPE细胞中绝大多数为后层IPE细胞。IPE和RPE细胞的形态及体外生长特点类似。     

视网膜色素上皮发育发生学的研究进展

视网膜色素上皮(retinal pigment epithelium,RPE)为一单层排列整齐的六角柱形细胞所组成,位于神经视网膜的光感受器和脉络膜的Bruch's膜之间,在维持光感受器细胞存活和正常功能方面起重要作用。多种先天性视网膜色素上皮疾病的发生与胚胎期的发育发生有着密切的关系。本文对RPE胚胎发育的基本过程、诱导RPE发生发育的信号分子、调控RPE发生发育的基因及维持RPE分化的信号通路等几个方面做一综述。     

视网膜脱离状态下兴奋性氨基酸含量变化对色素上皮作用的实验研究

目的 评价视网膜脱离状态下兴奋性氨基酸含量变化对视网膜色素上皮增殖的影响。方法 在不同时期检测脱离视网膜内兴奋性氨基酸含量并观察视网膜色素上皮的增殖情况。结果 视网膜脱离后8h视网膜内兴奋性氨基酸含量[Glu（4.68±1.22）nmol/mg,Asp（0.53±0.23）nmol/mg]和视网膜色素上皮增殖指数（18.41％±0.22％）明显升高,与对照组相比有显著性差异（P<0.05）。结论 视网膜脱离后早期视网膜内兴奋性氨基酸含量明显增加;脱离后视网膜色素上皮增殖,其机制与兴奋性氨基酸刺激密切相关。     

氧化损伤对体外培养人视网膜色素上皮细胞PEDF的影响

目的研究氧化损伤对人视网膜色素上皮(retinal pigment epithelial,RPE)细胞表达色素上皮细胞衍生因子(pigment epithelium derived factor,PEDF)的影响。方法体外培养人RPE细胞,加入浓度为600μmol.L-1H2O2分别作用不同时间(2h、8h、24h),采用免疫细胞化学法检测PEDF蛋白的表达,逆转录聚合酶链式反应(RT-PCR)法检测PEDF mRNA。结果免疫细胞化学染色对照组即有PEDF的阳性表达,而氧化损伤2h、8h、24h PEDF蛋白阳性表达量逐渐减少,染色由棕黄色变为黄色。各时间段两组结果比较,差异均具有统计学意义(P<0.05)。RT-PCR检测PEDF mRNA量与PEDF蛋白表达变化一致。结论氧化损伤能促使人RPE细胞PEDF表达下调,并在一定范围内与作用时间有关。     

Pattern dystrophies of the retinal pigment epithelium

Three members of a family in one generation were affected by a pattern dystrophy of the retinal pigment epithelium. The patients present typical hyperpigmented macular RPE lesions in a butterfly-shaped to (macro-)reticular pattern, and were all asymptomatic. Examination of 26 family members in 3 generations suggests autosomal recessive inheritance. The family showed some cases of congenital deutanomaly, and a female subject presented both disorders.     

视网膜色素上皮细胞相关细胞因子

很多眼底疾病与视网膜色素上皮 (retinalpigmentepithelium ,RPE)细胞功能改变有关。近期大量研究表明RPE细胞功能异常及分泌多种细胞因子参与这些疾病。检测这些细胞因子可反映RPE细胞的功能状态。对RPE参与的多种眼底疾病的研究和治疗提供了新的思路和手段     

视网膜色素上皮细胞凋亡的研究现状

细胞凋亡是一种由基因控制的程序化的细胞死亡过程，不同的基因参与凋控该过程。目前的研究表明，视网膜色素上皮细胞参与多种玻璃体视网膜病变的发生与发展。阐述了视网膜色素上皮细胞凋亡的概况、相关基因以及在玻璃体视网膜病变过程中所起到的作用，探索通过视网膜色素上皮细胞凋亡预防和治疗这些疾病的新途径。     

双重荧光标记法检测人视网膜色素上皮细胞吞噬的功能

目的:检测人视网膜色素上皮(humanretinalpig-mentepithelium,HRPE)细胞特异性及非特异性吞噬动力学,比较二者的不同之处。方法:用双重荧光标记法检测HRPE细胞吞噬动力学,即分别用红色染料硫氰酸罗达明(sulforho-damine,SR)、绿色荧光染料异硫氰酸酯荧光素(FITC)标记HRPE细胞和视杆细胞外节膜盘(rodoutersegments,ROS)。用1×1010个/L的FITC-ROS及自发绿色荧光的乳胶微球(leatexbeads,LB)于37℃孵育培养的正常HRPE细胞,在孵育的不同时间(5min￣48h)去除孵育物,终止吞噬反应。用配有特殊三通广谱吸收波长,长工作距离镜头的荧光显微镜实时,活体观察并记录结合及吞噬的数量。用扫描电镜及激光共聚焦扫描显微镜证明HRPE细胞对LB及ROS结合与吞噬。结果:孵育0.25h时ROS已结合于HRPE细胞表面,0.5h时可见极少数的ROS被HRPE细胞摄入细胞内;之后的孵育过程中被结合及被吞噬的ROS数目不断增加,至孵育18h对ROS的结合达到饱和,但摄入过程继续进行,至孵育24h,对ROS的吞噬达到饱和。当HRPE细胞与LB孵育时,至1.5h结合方启动,6h摄入开始;在观察的48h内被结合及被吞噬的LB数目随时间延长而呈线性增加。结论:HRPE细胞的特异性及非特异性吞噬动力学明显不同,HRPE细胞对ROS的结合及吞噬比其对LB的结合及吞噬发生得更早,而且结合及吞入过程均具有时间饱和性。     

猫视网膜脱离后视网膜色素上皮细胞的行为观察

目的 观察猫视网膜脱离后，视网膜色素上皮细胞(RPE)的形态学改变及行为变化。方法 28只猫利用微穿刺技术将0．25％Healon注入到视网膜下腔造成视网膜脱离。脱离0．5～90d的视网膜用3％戊二醛固定，加工成组织切片，光镜和电镜下观察RPE细胞形态学变化。结果 视网膜脱离24h，视网膜色素上皮细胞顶端突起被短而均匀的指样突起所取代，RPE细胞顶端表面开始出现耸起。随着脱离时间的延长，细胞表面的这种耸起变得更加明显。脱离14d，RPE细胞开始向视网膜下腔迁移，1～2个月后，在视网膜下腔可以观察到一些小的RPE细胞团簇。结论 视网膜脱离后，RPE细胞的形态发生迅速改变，并且依赖视网膜脱离的时间呈进行性进展。视网膜脱离能诱导RPE细胞形状发生变化，这种形状改变可能与细胞的增殖行为有关。