Autologous translocation of the retinal pigment epithelium and choroid in the treatment of neovascular age‐related macular degeneration

Purpose: To evaluate clinical results of an autologous translocation of retinal pigment epithelium (RPE) and choroid in the treatment of neovascular age‐related macular degeneration (AMD). Methods: Twelve eyes which underwent surgery for neovascular AMD were included into the study, in four eyes moderate or massive submacular haemorrhage was present. The surgical procedure included standard pars plana vitrectomy; cataract surgery in phakic patients; peripheral 180°‐retinotomy; extraction of the submacular neovascular complex and removal of blood if present; preparation of a full‐thickness graft consisting of RPE, Bruch’s membrane and choroid; translocation of the graft to the macular area; and silicone oil endotamponade. Results: Visual acuity (VA) ranged from perception of hand movements (HM) to 20/125 (median, counting fingers (CF)–1/50) before surgery. During follow‐up (FU) mean, 11.1 months, VA increased to a maximum median of 1/10 (range, HM–20/40). At the end of FU, VA had dropped to a median of CF–1/40 (range, HM–20/50). Comparing VA preoperatively and at the end of FU, VA had improved in six eyes, was unchanged in three eyes, and had deteriorated in three eyes. One eye had reading ability. Surgery‐associated postoperative complications impairing the functional outcome occurred in five eyes, including rhegmatogenous retinal detachment and proliferative vitreoretinopathy. Revision surgery had to be performed in four eyes (30%). Three eyes had to be left with permanent silicone endotamponade. Results tended to be better in the subgroup of eyes with massive submacular haemorrhage preoperatively. Conclusion: Functional results of a translocation of RPE and choroid were heterogeneous and rather disappointing in this study. Results may have been influenced negatively by case selection. We found a relatively high rate of adverse events in the postoperative course. In selected cases, e.g. massive submacular haemorrhage or progressive neovascular AMD unresponsive to other treatment options, autologous translocation of RPE and choroid may still be considered.     

脂褐素与年龄相关性黄斑变性

年龄相关性黄斑变性是发达地区老年人最常见的致盲眼病之一,其具体发病机制不清,治疗效果也不明显。近年来,人们发现视网膜色素上皮内脂褐素的增多和年龄相关性黄斑变性的发生有一定关系,我们就2者之间关系的研究情况加以综述。     

脂褐素在年龄相关性黄斑变性发病中的作用

目前年龄相关性黄斑变性是影响老年人视力和生存质量的最重要致盲眼病之一,患病率逐年提高。由于对其确切发病机制不明,故缺乏有效的防治措施。近年来研究证明,脂褐素随年龄的增长沉积于视网膜下,通过慢性光化学作用造成视网膜色素上皮细胞功能异常,光感受器细胞变性增加,脉络膜新生血管形成,导致年龄相关性黄斑变性的发生。     

单次注射康柏西普治疗渗出型AMD患者RPE隆起面积与容积变化

目的　观察单次玻璃体内注射康柏西普治疗渗出型年龄相关性黄斑变性（ａｇｅ-ｒｅｌａｔｅｄｍａｃｕｌａｒｄｅｇｅｎｅｒａｔｉｏｎ,ＡＭＤ）患者的视网膜色素上皮（ｒｅｔｉｎａｌｐｉｇｍｅｎｔｅｐｉｔｈｅｌｉｕｍ,ＲＰＥ）隆起的面积及容积变化,以评价康柏西普治疗ＡＭＤ的短期疗效及安全性。方法　选取渗出型ＡＭＤ患者４０例（４５眼）,所有患者均行玻璃体内注射康柏西普０．０５ｍＬ（０．５ｍｇ）治疗。术前、术后１周、１个月及３个月复诊行Ｃｉｒｒｕｓ５０００ＯＣＴ检查,比较治疗前后最佳矫正视力（ｂｅｓｔｃｏｒｒｅｃｔｅｄｖｉｓｕａｌａｃｕｉｔｙ,ＢＶＣＡ）、黄斑中心凹厚度及ＲＰＥ隆起的面积、容积。结果　术后１周、１个月,ＢＣＶＡ（ｌｏｇＭＡＲ）由术前１．２５±０．７９分别提升至０．９２±０．６６（Ｐ＜０．００１）和０．９４±０．６１（Ｐ＜０．００１）,３ｍｍ圆内ＲＰＥ隆起面积及容积由术前的（２．９１±１．７３）ｍｍ２、（０．５０±０．７３）ｍｍ３分别降至（２．７５±１．８２）ｍｍ２（Ｐ＝０．０２４）、（０．４２±０．７１）ｍｍ３（Ｐ＝０．０２０）和（２．３３±１．８５）ｍｍ２（Ｐ＝０．００２）、（０．３２±０．０９）ｍｍ３（Ｐ＝０．０４６）。术后３个月时ＢＣＶＡ下降至１．３０±０．８２,与术前差异无统计学意义（Ｐ＞０．０５）;３ｍｍ圆内ＲＰＥ隆起面积及容积增加到（２．７３±１．８１）ｍｍ２、（０．５１±０．７９）ｍｍ３,与术前相比差异均无统计学意义（均为Ｐ＞０．０５）。术后１周、１个月、３个月５ｍｍ圆内ＲＰＥ隆起面积及容积与术前差异均无统计学意义（均为Ｐ＞０．０５）。黄斑中心凹厚度仅在术后１个月由术前（２４４．５６±２５．３７）μｍ降至（２３４．９１±２１．５０）μｍ（Ｐ＝０．０４４）。所有患者均未出现严重眼部并发症及全身不良反应。结论　康柏西普短期内治疗渗出型ＡＭＤ可显著提高视力,恢复视网膜结构,具有良好的安全性。     

Relationship between macular pigment and visual acuity in eyes with early age‐related macular degeneration

Purpose: Today the extent to which MP impacts visual function in early AMD remains unclear. This study examines the relationship between macular pigment optical density (MPOD) and high‐contrast visual acuity (HC‐VA) and low‐contrast visual acuity (LC‐VA) in eyes with early age‐related macular degeneration (AMD). Methods: Measurements were made in 22 subjects with early AMD and 27 healthy control subjects. Distance best‐corrected VA was measured using HC (96%) and LC (10%) Bailey‐Lovie logMAR letter charts under photopic luminance conditions. MPOD was determined at the fovea through apparent motion photometry using the cathode ray tube‐based Metropsis psychophysical vision test (Cambridge Research Systems). Results: No significant differences in foveal MPOD were detected between the control eyes (0.30 ± 0.24 log units) and eyes with early AMD (0.27 ± 0.15 log units). Neither were differences detected between the two groups in mean HC‐ and LC‐VA. Foveal MPOD showed significant correlation with both photopic HC‐VA (r = ?0.47, p = 0.0008) and LC‐VA (r = ?0.46, p = 0.0008) such that as MPOD increased, photopic HC‐VA and LC‐VA improved (lower logMAR values). Conclusions: Low MP levels were related to worse visual function in both healthy eyes and eyes with early AMD. Our findings provide direction for future studies designed to improve retinal function through the use of oral supplements known to increase MP levels, especially in eyes with AMD and a low MPOD.     

碘酸钠诱导非渗出型年龄相关性黄斑变性模型的研究

目的：研究10g/L胼酞嗪滴眼液对剂量为35mg/kg的NaIO3诱导的大鼠RPE变性的对抗作用。 方法：经舌下静脉予Brown Norway大鼠分别注射不同剂量的NaIO3及生理盐水,注射3,7,14及28d后测量ERG的a、b、c、FO及LP波,同时进行眼底彩照和眼底荧光血管造影检查。用光学显微镜或自体荧光平片对部分大鼠进行组织学研究。在体外培养RPE-19细胞,观察不同浓度的NaIO3对细胞的影响并测其细胞增殖率。经舌下静脉予BrownNorway大鼠注射剂量为35mg/kg的NaIO3。NaIO3组大鼠注射NaIO3后用生理盐水点眼,10g/L胼酞嗪＋NaIO3组大鼠注射NaIO3后用10g/L胼酞嗪滴眼液点眼,对照组不注射NaIO3,用生理盐水点眼,皆为3次/d,连续点4wk,然后测ERGc波。 结果：注射NaIO3后,高剂量组如30、40和60mg/kgNaIO3组的各种ERG波的振幅明显降低,低剂量组则变化不大。眼底彩照显示注射NaIO3后3d30mg/kg组出现部分视网膜坏死,视网膜坏死程度与注射后时间及注射量呈正相关,低剂量组没有明显改变。平片显示,注射NaIO3后3d30mg/kg组及更高剂量组单层RPE细胞出现坏死。组织学研究提示,注射NaIO330mg/kg组和低剂量组未发现明显变化。体外实验发现,浓度≥30mg/LNaIO3组RPE-19细胞增殖率降低。注射剂量为35mg/kgNaIO3后4wk,和对照组相比,NaIO3组大鼠ERGc波显著降低到对照组的31%（P〈0.01）。10g/L胼酞嗪＋NaIO3组和NaIO3组相比,大鼠ERGc波显著升高到对照组的50%（P〈0.05）。 结论：NaIO3诱导的PRE细胞凋亡受剂量和时间的双重影响。剂量为30-40mg/kgNaIO3适用于非渗出型年龄相关性黄斑变性的体内造模。胼酞嗪可能延缓非渗出型年龄相关性黄斑变性的发展进程,可能用于治疗非渗出型年龄相关性黄斑变性。     

Effects of hydralazine on NaIO3 -induced rat retinal pigment epithelium degeneration

AIM: To study the effects of 10g/L hydralazine eye drops on 35mg/kg NaIO₃ -induced degeneration in rat eyes. METHODS: Various doses of NaIO₃ and/or saline alone were injected into Brown Norway rats from hypoglossal vein. After 3, 7, 14 or 28 days of injection, ERG a-, b-, c-wave, fast oscillation (FO) and light peak (LP) were measured along with retinal colored pictures and fluorescein angiography(FA) taken. Some rats were chosen to study the histology of retinas by light microscopy and autofluorescence of retina flatmounts. Different concentrations of NaIO₃ were given to RPE-19 cells, and cell proliferation rate was measured. For hydralazine study, 35mg/kg NaIO₃ was injected into Brown Norway rat from hypoglossal vein. NaIO_{3 group was treated with saline alone after NaIO3 injection, 10g/L hydralazine+ NaIO3 group was treated with 10g/L hydralazine eyedrops after NaIO3 injection whereas normal group was treated with saline alone without NaIO3 injection. All eyedrops were instilled locally 3 times a day for 4 weeks and ERG c-wave was measured at the end of 2 and 4 weeks. RESULTS: After NaIO3 administration, the amplitude of all ERG waves fell markedly in large dose groups at 30, 40 or 60mg/kg NaIO3. Not many changes were observed in groups treated with <30mg/kg NaIO3. Some retinal necrosis appeared from 3 days post-injection (PI) in 30mg/kg NaIO3 group, which became more serious in larger dose groups or longer treatment time, but no apparent change was found in smaller dose groups. Similarly, on the retina flatmount, RPE monolayer showed necrosis from 3 days PI in the 30mg/kg NaIO3 and larger dose groups. On histological examination, no significant change was seen in 30mg/kg NaIO3 and lower concentration groups. In cell culture experiment, changes were found in RPE-19 cells proliferation rate with a concentration of NaIO3 at 30mg/L or higher. In hydralazine experiments, 4 weeks after injection of NaIO3, ERG c-wave fell markedly in NaIO3 group to 31% of control group(P <0.01). The ERG c-wave of hydralazine +NaIO3 group fell only to 50% of control group (P <0.05). This was a 61% reversal of the c-wave of NaIO3 treated group. CONCLUSION: Retinal pigment epithelium(RPE) degeneration induced by NaIO3 was both dose and time dependent. Around 30 to 40mg/kg NaIO3 would be the optimal to be used as a non-exudative age-related macular degeneration(AMD) rat model. Hydralazine may postpone the development of non-exudative AMD.}     

碘酸钠诱导非渗出型年龄相关性黄斑变性模型的研究(英文)

目的:研究10g/L胼酞嗪滴眼液对剂量为35mg/kg的NaIO3诱导的大鼠RPE变性的对抗作用。方法:经舌下静脉予Brown Norway大鼠分别注射不同剂量的NaIO3及生理盐水,注射3,7,14及28d后测量ERG的a、b、c、FO及LP波,同时进行眼底彩照和眼底荧光血管造影检查。用光学显微镜或自体荧光平片对部分大鼠进行组织学研究。在体外培养RPE-19细胞,观察不同浓度的NaIO3对细胞的影响并测其细胞增殖率。经舌下静脉予BrownNorway大鼠注射剂量为35mg/kg的NaIO3。NaIO3组大鼠注射NaIO3后用生理盐水点眼,10g/L胼酞嗪+NaIO3组大鼠注射NaIO3后用10g/L胼酞嗪滴眼液点眼,对照组不注射NaIO3,用生理盐水点眼,皆为3次/d,连续点4wk,然后测ERGc波。结果:注射NaIO3后,高剂量组如30、40和60mg/kgNaIO3组的各种ERG波的振幅明显降低,低剂量组则变化不大。眼底彩照显示注射NaIO3后3d30mg/kg组出现部分视网膜坏死,视网膜坏死程度与注射后时间及注射量呈正相关,低剂量组没有明显改变。平片显示,注射NaIO3后3d30mg/kg组及更高剂量组单层RPE细胞出现坏死。组织学研究提示,注射NaIO330mg/kg组和低剂量组未发现明显变化。体外实验发现,浓度≥30mg/LNaIO3组RPE-19细胞增殖率降低。注射剂量为35mg/kgNaIO3后4wk,和对照组相比,NaIO3组大鼠ERGc波显著降低到对照组的31%(P<0.01)。10g/L胼酞嗪+NaIO3组和NaIO3组相比,大鼠ERGc波显著升高到对照组的50%(P<0.05)。结论:NaIO3诱导的PRE细胞凋亡受剂量和时间的双重影响。剂量为30~40mg/kgNaIO3适用于非渗出型年龄相关性黄斑变性的体内造模。胼酞嗪可能延缓非渗出型年龄相关性黄斑变性的发展进程,可能用于治疗非渗出型年龄相关性黄斑变性。     

视网膜色素上皮细胞氧化应激相关microRNA的鉴定

目的：应用miRNA表达谱芯片筛选视网膜色素上皮细胞与氧化应激相关的miRNA,为更加全面深入地研究年龄相关性黄斑病变(age-related macular degeneration,AMD)发生的分子机制提供新的思路。

方法：培养D407细胞,分别使用100、200、400μmol/L H₂O₂处理细胞24h后,Trizol试剂抽提细胞总RNA,使用Exiqon miRCURY LNA^TM microRNA表达谱芯片(miRBase 16.0数据库)检测不同浓度处理后D407细胞miRNA的表达差异,并将不同浓度处理后的变化进行聚类分析。使用Stem loop realtime PCR对芯片结果进行验证,并运用生物信息学方法预测差异miRNA调控的靶基因。

结果：芯片所包含的1 425个已知miRNA中,共有367个在不同浓度H₂O₂处理后表达发生变化。通过Treeview软件进行聚类分析发现miR-31等17个miRNA随H₂O₂浓度的升高呈现逐渐降低的趋势,miR-206等7个则逐渐升高。PCR验证显示芯片结果准确性较好。

结论：H₂O₂作用前后RPE的miRNA表达存在明显差异,miRNA作为转录后水平的调节分子,参与了细胞氧化应激反应,可能在AMD的发生发展中起有重要作用。     

Outer retinal cysts in age‐related macular degeneration

Purpose: To describe novel cystic structures (‘outer retinal cysts’ or ORC) found in the outer retina in age‐related macular degeneration (AMD). Methods: One hundred and seventy‐three consecutive eyes of 88 AMD patients were prospectively examined with spectral domain optical coherence tomography (SD‐OCT). The prevalence of ORCs was searched, and their sizes and shapes were determined. Results: SD‐OCT revealed round or ovoid, intraretinal, hyporeflective cystic structures with a hyperreflective border in 60 eyes (56%) with neovascular AMD and in six eyes (21%) with atrophic AMD. These cystic structures were of different sizes and shapes. They remained stable in all the patients after a follow‐up period of 6 months. Conclusions: Outer retinal cyst is a new type of cystic structure recently identified in AMD patients. ORCs should not be confused with intraretinal exudates or cystoid cavities and therefore do not require any treatment. The histopathological nature of ORC remains to be determined. Further studies are necessary to determine their true origin.     

Cultivation of retinal pigment epithelial cells from human choroidal neovascular membranes in age related macular degeneration

A method is described for cultivating retinal pigment epithelial cells from choroidal neovascular membrane (CNV) specimens that were surgically removed in patients with age-related macular degeneration (AMD). CNV specimens of 43 patients were available for cultivation. They were incubated in supplemented DMEM/Ham's F12 cell culture medium on microporous semipermeable filter membranes. Thirty-four specimens gave rise to cell cultures, 28 of which could be subcultivated for up to 15 passages. The membrane type as classified by fluorescence angiography was compared with cellular growth in vitro. Immunocytochemistry revealed a uniform expression of cytokeratin 18 and vimentin, while factor 8, glial fibrillary acidic protein and alpha smooth muscle actin were absent in all 21 cultures stained. The expression of RPE markers cellular retinaldehyde binding protein (CRALBP) and RPE65 was detected by RT-PCR in all cultures tested. An epithelial character of the cultures was supported by the presence of apical microvilli as determined by electron microscopical studies. Therefore, the cell cultures from CNV in AMD bear characteristics of retinal pigment epithelial cells. For the first time, this cell culture system holds the potential to study human RPE cells in the context of neovascular AMD in vitro.     

视网膜色素上皮细胞间紧密连接及其在AMD发病过程中的作用研究进展

年龄相关性黄斑变性(AMD)是引起老年人群不可逆性视力损害的常见眼病。视网膜色素上皮细胞(RPECs)间紧密连接(TJ)是血-视网膜外屏障(oBRB)的重要结构单元。紧密连接在AMD的发病过程中有所缺陷,进而促进oBRB的破坏,加速AMD的发生和进展。本文将对紧密连接与紧密连接蛋白在维持oBRB功能、紧密连接蛋白异常与oBRB破坏在AMD发病过程中的作用研究进行综述,以期为AMD治疗的研究提供新的思路。     

Retinal pigment epithelium tears after intravitreal injection of ranibizumab for predominantly classic neovascular membranes secondary to age‐related macular degeneration

Acta Ophthalmol. 2010: 88: 736–741

Abstract.

Purpose: Retinal pigment epithelium (RPE) tear is an extremely rare complication in patients with classic neovascular membranes without RPE detachment. We evaluate their incidence and functional outcome following treatment with intravitreal ranibizumab. Methods: Observational study of 72 consecutive patients (74 eyes) treated at Jules Gonin University Eye Hospital, Lausanne, with intravitreal ranibizumab 0.5 mg for classic choroidal neovascularization (CNV) between March 2006 and February 2008. Best‐corrected visual acuity (BCVA), fundus examination and optical coherence tomography were recorded monthly; fluorescein angiography was performed at baseline and repeated at least every 3 months. Results: RPE tears occurred in four (5.4%) eyes temporal to the fovea, after a mean of four injections (range 3–6). Mean baseline BCVA was 0.25 decimal equivalent (logMAR 0.67) and improved despite the RPE tear to 0.6 decimal equivalent (logMAR 0.22). Conclusion: RPE tears following intravitreal ranibizumab injections for classic CNV can occur in about 5% of patients, even in the absence of baseline RPE detachment. Nevertheless, vision may improve provided the fovea is not involved.     

Treatment of age‐related macular degeneration

Age‐related macular degeneration (AMD) is the greatest cause of legal blindness in the western world. Established treatments include argon laser photocoagulation of extrafoveal choroidal neovascularisation (CNV) and photodynamic therapy of selected sub‐foveal CNV. Newer approaches are targeting the angiogenic pathway in CNV development. Currently, other treatment modalities, such as radiotherapy and transpupillary thermotherapy do not have a clear role to play. Surgical options are experimental and only available in some centres for selected patients. Prevention of AMD remains elusive. Dietary supplements may have a role, while statins and prophylactic laser photocoagulation of drusen remain experimental. This paper explains the principles behind these approaches.     

脂褐素与年龄相关性黄斑变性

年龄相关性黄斑变性(ARMD)是引起中老年人视力丧失的首要原因,其确切病因尚未明了,故治疗效果不佳。脂褐素随着年龄增长在视网膜色素上皮的积累是眼睛老化的标志,通过光化学作用等影响正常视网膜色素上皮细胞的功能,与ARMD的发生发展有一定联系。本文就脂褐素及其与ARMD的关系进行综述。     

Age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible severe visual loss in the United States in people over 50 years of age. The nonexudative stage includes hard drusen (associated with localized dysfunction of the retinal pigment epithelium [RPE]), soft drusen (associated with diffuse dysfunction of the RPE), and geographic (areolar) atrophy. These fundus changes may predispose the eye to develop the neovascular/exudative stages of AMD. Most patients who develop severe visual loss from AMD have this exudative stage. Treatment for AMD has been shown to be effective for only a small proportion of patients who have a well-defined choroidal neovascular membrane (CNVM) more than 200 microns from the foveal center. Even in successfully treated cases, severe visual loss is postponed only for about 18 months because of the high rate of recurrent CNVMs that extend into the fovea. Thus, despite recent breakthroughs in laser treatment for AMD, most patients who develop the exudative form of AMD will develop central visual impairment. At the present time, the only available treatments for the majority of patients who develop the exudative form of AMD are low vision aids. Investigators are currently evaluating whether treatment is effective for membranes within 200 microns of the foveal center. Future studies need to be directed toward further understanding of the pathogenesis, treatment and prevention of the blinding complications of AMD.     

ACTA‐EVER lecture 2007 The retinal pigment epithelium: friend or foe?

The retinal pigment epithelium (RPE) plays an important role in the physiology and pathophysiology of the vertebrate retina. The RPE absorbs fluid from the retinal extracellular space, via a proton–lactate–water co‐transport mechanism located in the apical membrane of the epithelium. This mechanism can account for the apparent capability of the RPE to absorb water against an osmotic gradient. RPE cells participate in retinal wound healing. We have created a porcine model of experimental choroidal neovascularization (CNV). In this model, the CNV eventually becomes enveloped by seemingly proliferating RPE cells. By means of 5‐bromo‐2‐deoxyuridine (BrdU) labelling, we studied the proliferation of RPE cells in the porcine eye after experimental posterior pole injury. Surprisingly, we found that only the peripheral RPE cells incorporated the BrdU label, indicating that central injury elicits peripheral RPE proliferation. This might suggest the existence of a peripheral pool of RPE stem cells. RPE cell proliferation plays a role in the pathological wound healing known as proliferative vitreoretinopathy. Antiproliferative agents have been tried to treat this condition but with little success so far. We report on a drug delivery system under development where a prodrug of the antimetabolite 5‐fluoro‐uracil (5‐FU) is suspended in the silicone oil used as a surgical device in the treatment of proliferative vitreoretinopathy (PVR). The theoretical advantage of this approach is that it allows for long contact times between therapeutic, and non‐toxic, concentrations of 5‐FU and the RPE.