Silva R M, Faria de Abreu J R, Cunha-Vaz J G
Servico de Oftalmologia dos Hospitais da Universidade Coimbra, Portugal.
Graefes Arch Clin Exp Ophthalmol. 1995 Nov;233(11):721-6. doi: 10.1007/BF00164677.
Extensive clinical studies on retinal branch vein occlusion have not yet been able to clarify its pathogenesis. A study designed to look at the associated blood-retina barrier changes may contribute to a better understanding of the different forms of evolution of this pathology.
A prospective study was done in seven patients with recent large temporal branch vein occlusion. Vitreous fluorophotometry, fluorescein angiography and retinal colour photography were performed within the 1st week after the onset of symptoms, 1 week later, and at 12 and 24 weeks.
A more marked blood-retina barrier breakdown was found at 1, 2, 12 and 24 weeks in the eyes that later developed extensive capillary nonperfusion.
Our results suggest that the breakdown of the blood-retina barrier may play an important role in the subsequent development of retinal nonperfusion in eyes with large branch vein occlusion. We postulate that the eyes that will present later extensive capillary nonperfusion develop, from the initial stages of the disease, a progressive "ischaemic capillaropathy" characterized by blood-retina barrier breakdown. Retinal pigment epithelium degeneration and arterial lumen narrowing, secondary to the vein obstruction, may help to increase and perpetuate the blood-retina barrier breakdown during the first 6 months after the occlusion.
关于视网膜分支静脉阻塞的广泛临床研究尚未能阐明其发病机制。一项旨在观察相关血视网膜屏障变化的研究可能有助于更好地理解这种病理状况的不同演变形式。
对7例近期发生颞侧大分支静脉阻塞的患者进行了一项前瞻性研究。在症状出现后的第1周内、1周后、12周和24周进行了玻璃体荧光光度测定、荧光素血管造影和视网膜彩色摄影。
在后来出现广泛毛细血管无灌注的眼中，在1周、2周、12周和24周时发现血视网膜屏障破坏更为明显。
我们的结果表明，血视网膜屏障的破坏可能在大分支静脉阻塞性眼病随后发生视网膜无灌注的过程中起重要作用。我们推测，那些随后会出现广泛毛细血管无灌注的眼睛，从疾病的初始阶段就会发展出一种以血视网膜屏障破坏为特征的进行性“缺血性毛细血管病”。继发于静脉阻塞的视网膜色素上皮变性和动脉管腔狭窄可能有助于在阻塞后的前6个月内增加并使血视网膜屏障破坏持续存在。
