Abstract：
Form deprivation (FD) is a widely employed experimental paradigm, typically used to induce unilateral myopia in animal models. This model is weakened by potential influence upon the FD eye from vision in the freely-viewing contralateral eye, which could be eliminated by imposing FD in both eyes; but while a few previous studies have explored the feasibility of inducing bilateral FD in chicks, substantial discrepancies in treatment outcomes were noted. Consequently, this study aimed to establish a bilateral FD myopia model in chicks, with validation by investigating the associated ocular growth patterns, feeding, and social behavior. Six-day-old chicks were treated with bilateral (n = 21) or unilateral (n = 10) FD for 12 days; the fellow untreated eyes in the unilateral FD group served as controls. Refractive error, corneal power, and ocular axial dimensions were measured at 4-day intervals after the onset of form deprivation, with a Hartinger refractometer, a custom-made videokeratography system, and a high-resolution A-scan ultrasonographer, respectively. Body weight was monitored to assess the chick\'s physical development. Our results showed that birds treated with bilateral FD grew as robustly as the unilaterally form-deprived chicks, with similar or slightly heavier body weights and mortalities. Unilateral FD induced significantly higher myopia in the treated eye, with stronger corneal power, deeper anterior and vitreous chambers, and longer axial length. Moreover, either bilaterally or unilaterally FD eyes developed similar refractive error (bilateral FD, left: -28.03 ± 9.06 D, right: -28.44 ± 9.45 D; unilateral FD: -29.48 ± 8.26 D) and ocular biometric changes; but choroidal thickness was thicker in bilaterally FD eyes, rather than thinner as in unilaterally FD eyes. In addition to the highly synchronized (symmetrical, parallel) development reported previously in bilateral FD, we found in this study that the correlations between bilaterally form-deprived eyes were highest for ocular biometric parameters directly contributing to myopia development, including corneal power (r = 0.74 to 0.93), anterior chamber depth (r = 0.60 to 0.85), vitreous chamber depth (r = 0.92 to 0.94), and axial length (r = 0.90 to 0.96). The remarkably synchronized growth pattern confirmed the feasibility of the bilateral FD paradigm for future research on myopia.
摘要：
形式剥夺(FD)是一种广泛采用的实验范式，在动物模型中通常用于诱导单侧近视。该模型因自由观察对侧眼睛的视觉对FD眼睛的潜在影响而减弱，这可以通过在两只眼睛中施加FD来消除；但是尽管以前的一些研究已经探索了在雏鸡中诱导双侧FD的可行性，研究人员注意到治疗结局存在重大差异.因此,本研究旨在建立雏鸡双侧FD近视模型,通过调查相关的眼部生长模式进行验证，喂养,和社会行为。6天大的雏鸡接受双侧（n=21）或单侧（n=10）FD治疗12天；单侧FD组中未治疗的眼睛作为对照。折射错误，角膜力，和眼轴尺寸在形式剥夺开始后每隔4天测量一次，用Hartinger折射计,定制的视频摄影系统，和一个高分辨率的A-扫描超声波扫描仪，分别。监测体重,评估小鸡的身体发育。我们的结果表明，用双侧FD治疗的鸟类与单方面缺乏形态的雏鸡一样生长强劲，体重和死亡率相似或稍重。单侧FD在治疗的眼睛中引起明显更高的近视，具有更强的角膜力，较深的前房和玻璃体腔，和更长的轴向长度。此外，双侧或单侧FD眼出现类似的屈光不正(双侧FD,左：-28.03±9.06D，右侧：-28.44±9.45D；单侧FD：-29.48±8.26D）和眼部生物特征变化；但双侧FD眼中脉络膜厚度较厚，而不是像单侧FD眼睛那样瘦。除了高度同步（对称，平行)先前在双边FD中报告的发展，我们在这项研究中发现，双侧形态剥夺的眼睛之间的相关性对于直接导致近视发展的眼部生物特征参数最高，包括角膜屈光力（r=0.74至0.93），前房深度（r=0.60至0.85），玻璃体腔深度(r=0.92~0.94),和轴向长度（r=0.90至0.96）。显著同步的生长模式证实了双侧FD范式用于未来近视研究的可行性。
