MACTEL1

本研究是一项开放标签的初步研究，玻璃体内注射雷珠单抗的参与者与黄斑毛细血管扩张。Genentech将为该试验提供雷珠单抗。本研究将选择5名患有新血管形成的研究受试者。患有双侧黄斑毛细血管扩张的受试者的研究眼将被指定为通过视力测量、荧光素血管造影和OCT结果确定的受累严重程度更高的眼。但是，如果由于不可逆的结构变化（广泛萎缩和色素变性、慢性黄斑瘢痕形成），判断受累较严重的眼睛不太可能从治疗中获益，则可以考虑受累较轻的眼睛。如果双眼等效，研究者和受试者将确定研究眼。 将根据标准治疗对侧眼进行治疗。 由于这种情况的发病机制是未知的，人们只能推测血管内皮生长因子（VEGF）在这种情况下可能发挥的作用。 荧光素血管造影片上所见的渗漏反映了视网膜血管内皮功能障碍，尽管尚不确定这可能是原发性还是继发性疾病。 黄斑毛细血管扩张症的荧光素渗漏类似于糖尿病视网膜病变，其中VEGF已被证明在其发病机制中是重要的。 新生血管形成的发展，通常开始于视网膜内新生血管形成，然后发展成视网膜下和脉络膜新生血管形成，表明VEGF也可能参与该过程。 由于这些原因，我们认为重要的是要测试玻璃体内注射雷珠单抗治疗的可能作用。我们将了解这种治疗的可行性，同时了解任何安全问题。 我们并不完全了解在疾病的早期阶段视力丧失的原因。 很明显，新生血管过程将降低视力，其过程与其他新生血管形成原因（如年龄相关性黄斑变性）的过程相似。

This study is an open-label, pilot study of intravitreal injections of ranibizumab in participants with macular telangiectasia. Genentech will supply the ranibizumab for this trial. Five study participants, with neovascularization, will be selected for this study. The study eye in participants who present with bilateral macular telangiectasia will be designated as the eye with the greater severity of involvement as determined by visual acuity measurements, fluorescein angiography and OCT results. However, in the case where the more severely affected eye is judged to unlikely benefit from treatment due to irreversible structural changes (extensive atrophy and pigmentary change, chronic macular scarring), then the less severely affected eye may be considered. In cases where both eyes are equivalent, the investigator and participant will determine the study eye. The fellow eye will be treated according to standard-of-care. Because the pathogenesis of this condition is unknown, one can only speculate on the possible role of vascular endothelial growth factor (VEGF) in this condition. The leakage seen on fluorescein angiogram reflects on the endothelial dysfunction of the retinal vessels although it is not certain that this may be a primary or a secondary condition. The fluorescein leakage of macular telangiectasia resembles that of diabetic retinopathy where VEGF has proven to be important in its pathogenesis. The development of neovascularization, which often begins as intra-retinal neovascularization, which then develops into subretinal and choroidal neovascularization, suggests that VEGF may also be implicated in this process. For these reasons, we believe it is important to test the possible role of ranibizumab therapy with intravitreal injections of ranibizumab. We will learn about the feasibility of this treatment while we learn about any safety issues. We do not understand fully the cause of vision loss in the early stages of the disease. It is evident that the neovascular process will decrease vision in a similar process as that of other causes of neovascularization such as age-related macular degeneration.