Shiraz School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Retina. 2011 Jan;31(1):154-60. doi: 10.1097/IAE.0b013e3181e096f3.
The purpose of this study was to investigate the effect of intravitreal bevacizumab on an experimental rabbit model of penetrating posterior ocular injury.
The right eyes of 40 white New Zealand rabbits were included in a penetrating posterior ocular injury model that was consisted of a 5-mm circumferential incision placed 8 mm behind the limbus at the supratemporal quadrant. They were randomly divided into two groups. The rabbits in Group 1 (n = 20) received 1.25 mg (0.05 mL) of intravitreal bevacizumab via pars plana injection and those in Group 2 (control group, n = 20) received 0.05 mL of intravitreal balanced salt solution. On Day 28, the eyes were enucleated and evaluated by gross inspection and light microscopy. Clearance time of vitreous hemorrhage, presence of fibrous proliferation or retinal detachment, greatest linear dimension of fibrosis, and grade of fibrous extension were regarded as outcome measures. Nominal variables were evaluated by the chi-square or the Fisher's exact test; continuous variables were evaluated using the Mann-Whitney U test.
At the end of the surgery, all the eyes had moderate (n = 9 and 7 in the case and control groups, respectively) or severe vitreous hemorrhage (n = 11 and 13 in the case and control groups, respectively) (P = 0.52). Average clearance time of vitreous hemorrhage was 3.42 ± 2.71 and 6.47 ± 3.58 days in bevacizumab and control groups, respectively (P = 0.01). The incidence of ophthalmoscopically visible fibrous proliferation was 31.6% in the bevacizumab group and 63.2% in the control group (P = 0.05). The greatest linear dimension of fibrosis was 0.91 ± 1.14 mm in the bevacizumab group and 2.00 ± 1.58 mm in the control group (P = 0.02). Retinal detachment rate was 11% (n = 2, all rhegmatogenous) and 21% (n = 4, 2 rhegmatogenous and 2 tractional) in the bevacizumab and control groups, respectively (P = 0.66). Choroidal congestion, optic disk edema, and macular edema were seen in 1 eye (5.5%) of the bevacizumab group, whereas they were found in 4 (22%), 4 (22%) and 3 (16.5%) eyes of the control group, respectively. These differences, however, did not reach statistical significance.
This study showed that intravitreal injection of bevacizumab may reduce the extent of fibrovascular and/or fibrocellular proliferation and may accentuate the clearance of vitreous hemorrhage after an experimental model of posterior penetrating ocular injury in rabbits. These alterations may affect the long-term anatomical and/or functional success rate of posterior segment surgeries in these eyes.
本研究旨在探讨玻璃体内注射贝伐单抗对穿透性后眼球损伤实验兔模型的影响。
40 只新西兰大白兔右眼纳入穿透性后眼球损伤模型，在颞上象限角膜缘后 8mm 处做一个 5mm 的环形切口。它们被随机分为两组。第 1 组（n=20）通过睫状体平坦部注射 1.25mg（0.05ml）玻璃体内贝伐单抗，第 2 组（对照组，n=20）接受 0.05ml 玻璃体内平衡盐溶液。第 28 天眼球被摘出，通过大体检查和光镜进行评估。玻璃体积血清除时间、纤维增生或视网膜脱离的存在、纤维化的最大线性尺寸和纤维延伸程度作为观察指标。名义变量采用卡方或 Fisher 确切概率法检验；连续变量采用 Mann-Whitney U 检验。
手术结束时，所有眼均有中度（病例组 9 只眼，对照组 7 只眼）或重度玻璃体积血（病例组 11 只眼，对照组 13 只眼）（P=0.52）。玻璃体内出血清除时间平均为贝伐单抗组 3.42±2.71 天，对照组 6.47±3.58 天（P=0.01）。贝伐单抗组纤维增生的检出率为 31.6%，对照组为 63.2%（P=0.05）。纤维化的最大线性尺寸贝伐单抗组为 0.91±1.14mm，对照组为 2.00±1.58mm（P=0.02）。视网膜脱离率在贝伐单抗组为 11%（n=2，均为孔源性），对照组为 21%（n=4，2 例孔源性，2 例牵拉性）（P=0.66）。贝伐单抗组 1 只眼（5.5%）出现脉络膜充血、视盘水肿和黄斑水肿，对照组 4 只眼（22%）出现脉络膜充血、视盘水肿和黄斑水肿，4 只眼（22%）出现黄斑水肿，3 只眼（16.5%）出现黄斑水肿。然而，这些差异没有统计学意义。
本研究表明，玻璃体内注射贝伐单抗可能减少纤维血管和/或纤维细胞增生的程度，并可能加速实验性兔穿透性后眼球损伤模型的玻璃体积血清除。这些改变可能影响这些眼后部节段手术的长期解剖学和/或功能成功率。
