促红细胞生成素对视神经视网膜的保护作用

促红细胞生成素(Erythropoietin,EPO)主要作用于骨髓巨核前体细胞,刺激红系造血祖组织及早幼红细胞形成成熟的红细胞集落。近年来,大量的研究显示EPO和EPO受体在神经系统上有功能表达,在体外培养及动物试验中都显示了显著的神经保护功能。在眼科,青光眼、视网膜脱离、视网膜色素变性等疾病的共同病理机制是视网膜神经节细胞、光感受器细胞等神经元的凋亡,最终导致视力的丧失。因此,EPO的神经保护作用对治疗这些疾病有一定的实际意义。现总结了EPO的神经保护性质分子机制及信号传导途径,探讨EPO用于青光眼视神经保护治疗的基础和可能性。     

抗VEGF药物在视网膜血管性疾病围手术期的应用

血管内皮生长因子（VEGF）与新生血管性眼病密切相关,是有效的治疗靶点.抗VEGF药物能减少新生血管形成,降低血管通透性,为新生血管性眼病的治疗带来重大变革.目前雷珠单抗在国内已被批准用于湿性年龄相关性黄斑变性的治疗,在美国被批准用于糖尿病性黄斑水肿和视网膜静脉阻塞后黄斑水肿的治疗.抗VEGF药物也作为适应证外治疗药物用于其他新生血管性眼病的治疗,如增生性糖尿病视网膜病变、其他视网膜血管性疾病和新生血管性青光眼等.抗VEGF药物辅助手术治疗显示出明显的疗效,可减少术中、术后的并发症和疾病的复发率.就贝伐单抗和雷珠单抗等抗VEGF药物在视网膜血管性疾病围手术期的应用情况进行综述.     

Iron homeostasis and toxicity in retinal degeneration

Iron is essential for many metabolic processes but can also cause damage. As a potent generator of hydroxyl radical, the most reactive of the free radicals, iron can cause considerable oxidative stress. Since iron is absorbed through diet but not excreted except through menstruation, total body iron levels buildup with age. Macular iron levels increase with age, in both men and women. This iron has the potential to contribute to retinal degeneration.

Here we present an overview of the evidence suggesting that iron may contribute to retinal degenerations. Intraocular iron foreign bodies cause retinal degeneration. Retinal iron buildup resulting from hereditary iron homeostasis disorders aceruloplasminemia, Friedreich's ataxia, and panthothenate kinase-associated neurodegeneration cause retinal degeneration. Mice with targeted mutation of the iron exporter ceruloplasmin have age-dependent retinal iron overload and a resulting retinal degeneration with features of age-related macular degeneration (AMD). Post mortem retinas from patients with AMD have more iron and the iron carrier transferrin than age-matched controls.

Over the past 10 years much has been learned about the intricate network of proteins involved in iron handling. Many of these, including transferrin, transferrin receptor, divalent metal transporter-1, ferritin, ferroportin, ceruloplasmin, hephaestin, iron-regulatory protein, and histocompatibility leukocyte antigen class I-like protein involved in iron homeostasis (HFE) have been found in the retina. Some of these proteins have been found in the cornea and lens as well. Levels of the iron carrier transferrin are high in the aqueous and vitreous humors. The functions of these proteins in other tissues, combined with studies on cultured ocular tissues, genetically engineered mice, and eye exams on patients with hereditary iron diseases provide clues regarding their ocular functions.

Iron may play a role in a broad range of ocular diseases, including glaucoma, cataract, AMD, and conditions causing intraocular hemorrhage. While iron deficiency must be prevented, the therapeutic potential of limiting iron-induced ocular oxidative damage is high. Systemic, local, or topical iron chelation with an expanding repertoire of drugs has clinical potential.     

一氧化氮与眼病的关系

一氧化氮（nitric oxide,NO）是近年来眼科疾病的研究热点.其在体内一氧化氮合酶（nitric oxide synthase,NOS）的催化下生成,作为一种小分子介质调节眼部血流.诸多脉络膜视网膜疾病如葡萄膜炎、青光眼、缺血-再灌注损伤、前部缺血性视神经病变、糖尿病视网膜病变以及视网膜色素变性等发病机制中均发现NO的异常,与NO相拮抗的内皮素-1（Endothelin-1,ET-1）也日益受到关注.对NO合成途径的干预有望成为一种新的眼科治疗手段.     

Assessment of flow dynamics in retinal and choroidal microcirculation

Alterations in ocular blood flow have been implicated in mechanisms that lead to vision loss in patients with various ocular disorders such as diabetic retinopathy, glaucoma, and age-related macular degeneration. Assessment of retinal and choroidal blood flow is also a window to evaluate systemic diseases that affect microvasculature. Quantification and qualification of the blood flow in the retina and choroid help us understand pathophysiology, stratify disease risk, and monitor disease progression in these disorders. Multiple methods are used by researchers for assessment of blood flow, but a gold standard is lacking. We review commonly used methods, both invasive and noninvasive, for evaluation of blood flow, including intravital microscopy, laser Doppler velocimetry, laser Doppler flowmetry, laser interferometry, confocal scanning laser Doppler flowmetry, laser speckle flowgraphy, Doppler optical coherence tomography, blue-field entoptic simulation, retinal vessel caliber assessment, optical coherence tomography angiography, retinal function imaging, color Doppler imaging, and scanning laser ophthalmoscope angiogram. As technology evolves, better evaluation of blood flow in various ocular and systemic diseases will likely bring new perspectives into clinical practice and translate to better diagnosis and treatment.     

青蒿素在眼部疾病中的应用研究进展

青蒿素最初是来自甜艾草的倍半萜内酯家族。过去积累的证据表明,青蒿素及其衍生物在疟疾以外的其他几种疾病中具有保护作用,包括癌症、自身免疫性疾病、炎症性疾病、病毒和其他寄生虫相关感染。这种长期实践验证有效的抗疟药已被证明具有抗氧化、抗炎、抗细胞凋亡和抗兴奋性毒性的特性,这使其成为眼部环境的潜在治疗选择。本文综述了青蒿素在眼部疾病中的应用,包括葡萄膜炎、视网膜母细胞瘤、老年性黄斑变性、糖尿病视网膜病变和眼部新生血管,并强调了它们对各种疾病的潜在治疗可行性。     

Intravitreal drug therapy

The treatment of many ocular disorders is hampered because of poor penetration of systemically administered drugs into the eye. The tight junctional complexes (zonulae occludens) of the retinal pigment epithelium and retinal capillaries are the site of the blood-ocular barrier. This barrier inhibits penetration of substances, including antibiotics, into the vitreous. Over the last 18 years we have evaluated the nontoxic doses of various drugs. These include antibiotics and antifungals for treatment of bacterial and fungal endophthalmitis, antivirals for treatment of viral retinitis (specifically, when medication with these drugs poses the threat of toxicity to other organs). Intravitreal antineoplastic drugs have been studied to prevent cell proliferation in the vitreous cavity after retinal attachment surgery, which can lead to proliferative vitreoretinopathy (PVR). Furthermore, we evaluated the anti-inflammatory action of dexamethasone and cyclosporine A to reduce intraocular inflammation after intraocular surgery or in uveitis. Because these studies had been performed in the presence of the vitreous, which can slow down the diffusion of the drugs toward the retina, it was necessary to reevaluate the concentration of drugs which could be administered intravitreally in the vitrectomized eye. The nontoxic dose of numerous drugs when added to vitrectomy infusion fluid has also been evaluated. Furthermore, the role of vitrectomy in the treatment of bacterial fungal endophthalmitis has been studied and the role of vitrectomy in this ocular disorder is defined.     

雌激素在眼底疾病中的作用：一项值得关注的研究课题

雌激素除了作为性激素在生殖系统具有重要作用外，还影响骨骼、 心血管及神经系统的结构和功能；并且对老年性黄斑变性和视网膜神经变性等各种年龄相关 性眼底疾病的发生发展具有重要影响。雌激素在眼底疾病中的作用是一项值得关注的研究课 题，随着雌激素对眼底疾病的影响以及其 分子水平作用机制的了解逐渐深入，将为具有争议性的激素替代治疗提供新的认识依据。     

我国近五年眼底病诊疗技术进展

近5年来我国眼底病的诊疗水平快速提高,国际上新的诊疗理念、诊疗方法、诊疗设备不断被引入国内,极大地促进了国内眼底病诊疗技术的发展.在诊断方面,频域相干光断层扫描和眼底自发荧光检测技术的应用,不仅为临床诊断提供了更为详尽的图像信息,还有助于更加全面而深入地了解眼底疾病的特征及病理机制,引领我们进入了一个眼底疾病观察的新时代.在治疗方面,我国学者更是积极开展具有创新意义的临床研究,例如组织国内黄斑裂孔视网膜脱离治疗模式的多中心研究,开发具有自主知识产权的全人源抗体类融合蛋白KH902,采用带Bruch膜自体片状视网膜色素上皮移植并治疗年龄相关性黄斑变性、光动力疗法治疗中心性浆液性脉络膜视网膜病变、20G小切口微创玻璃体手术和视网膜中央动脉栓塞手术治疗技术等,有相当数量的眼底病临床研究论文在科学引文索引(SCI)收录的杂志上发表.由此表明我国眼底病临床研究已逐步走向世界并进一步与国际接轨.     

Color Doppler Imaging of Retinal Diseases

Color Doppler imaging (CDI) is a widely used method for evaluating ocular circulation that has been used in a number of studies on retinal diseases. CDI assesses blood velocity parameters by using ultrasound waves. In ophthalmology, these assessments are mainly performed on the retrobulbar blood vessels: the ophthalmic, the central retinal, and the short posterior ciliary arteries. In this review, we discuss CDI use for the assessment of retinal diseases classified into the following: vascular diseases, degenerations, dystrophies, and detachment. The retinal vascular diseases that have been investigated by CDI include diabetic retinopathy, retinal vein occlusions, retinal artery occlusions, ocular ischemic conditions, and retinopathy of prematurity. Degenerations and dystrophies included in this review are age-related macular degeneration, myopia, and retinitis pigmentosa. CDI has been used for the differential diagnosis of retinal detachment, as well as the evaluation of retrobulbar circulation in this condition. CDI is valuable for research and is a potentially useful diagnostic tool in the clinical setting.