Kozak Igor, Cheng Lingyun, Mendez Tim, Davidson Marie C, Freeman William R
Jacobs Retina Center, University of California at San Diego, Shiley Eye Center, La Jolla, California 92036-0946, USA.
Retina. 2006 Sep;26(7):811-7. doi: 10.1097/01.iae.0000244255.22406.2f.
Subretinal triamcinolone acetonide (TCA) might be a useful adjuvant in the treatment of subretinal neovascularization. The purpose of this study was to test the toxicity of subretinal TCA in the rabbit eye.
Sixteen New Zealand rabbits were vitrectomized and injected with either decanted TCA solution or vehicle. The concentration of injected TCA was 2 mg, and the delivered volume was 10 microL. Rabbits were examined on days 1, 3, and 7 and then once a week up to 3 months after surgery. Optical coherence tomography was performed at months 1, 2, and 3. After the last examination, which included electroretinography, the rabbits were killed, and the eyes were enucleated for histopathologic analysis.
Subretinal TCA appeared as a white circumscribed deposit. As the drug disappeared, areas of hyperpigmentation were seen adjacent to the drug deposit. Electroretinography tracings were normal, indicating no widespread toxic effect. Histologic analysis revealed areas of absence and/or hyperpigmentation of the retinal pigment epithelium and damage to photoreceptors and the outer nuclear layer of the retina.
Subretinal injection of TCA crystals can be toxic to the outer retina and retinal pigment epithelium. Whether the potential beneficial effect of such a high-dose steroid in limiting subretinal inflammation, angiogenesis, and proliferation outweighs toxicity can only be determined from a clinical trial.
视网膜下注射曲安奈德（TCA）可能是治疗视网膜下新生血管形成的一种有用辅助手段。本研究的目的是检测视网膜下注射TCA对兔眼的毒性。
16只新西兰兔接受玻璃体切割术，并注射倾析后的TCA溶液或赋形剂。注射的TCA浓度为2mg，注射量为10微升。在术后第1、3和7天对兔子进行检查，然后每周检查一次，直至术后3个月。在第1、2和3个月进行光学相干断层扫描。在包括视网膜电图在内的最后一次检查后，处死兔子，摘除眼球进行组织病理学分析。
视网膜下TCA表现为白色边界清晰的沉积物。随着药物消失，在药物沉积物附近可见色素沉着过度区域。视网膜电图描记正常，表明无广泛的毒性作用。组织学分析显示视网膜色素上皮存在缺失和/或色素沉着过度区域，以及光感受器和视网膜外核层受损。
视网膜下注射TCA晶体可对外侧视网膜和视网膜色素上皮有毒性。这种高剂量类固醇在限制视网膜下炎症、血管生成和增殖方面的潜在有益作用是否超过毒性，只能通过临床试验来确定。
Zotero 插件