Bantseev Vladimir, Oriowo Olanrewaju M, Giblin Frank J, Leverenz Victor R, Trevithick John R, Sivak Jacob G
School of Optometry, University of Waterloo, Waterloo, Ont., Canada N2L 3G1.
Exp Eye Res. 2004 May;78(5):925-31. doi: 10.1016/j.exer.2004.01.002.
The main objective of this study was to investigate the effect of in vivo hyperbaric oxygen (HBO) treatment of albino guinea pigs on ocular refractive state and optical properties of the lens in vitro, as well as on the integrity of the mitochondria of the lens. The animals were treated 30-35 times (2.5-3 months) or 70 times (6 months) with HBO. An increased level of lens nuclear light scattering was evident by slit-lamp at 30 treatments, and this increased at 70 treatments. After 30-35 HBO treatments a myopic shift in refractive state of the eye was seen in two separate studies with two different refractionists. Also, the average back vertex distance of the lens was significantly shorter after 35 HBO treatments while spherical aberration (focal variability) increased after 70 treatments. No difference in refractive state was noted after 70 HBO treatments (a reversal of the initial myopic effect). The mitochondrial distribution and morphology of the lens epithelium and the superficial cortical fibre cells were normal after both 35 and 70 HBO treatments, highlighting that HBO treatment does not affect the superficial cortex of the lens. The results of the in vitro lens optical analysis carried out in this study correlate with the myopia observed after 30-35 HBO in vivo treatments. A similar reversible myopia and increase in lens nuclear light scattering is known to occur in humans treated with HBO for extended periods and the results suggest that the myopia was caused by a change in the refractive index of the lens. The significant loss of sharp focus after 70 HBO treatments can be correlated with previous reports of biochemical and morphological changes associated with HBO-induced loss of lens nuclear transparency in mature guinea pigs. The guinea pig HBO model may be a useful approach for the study of lens development and refractive error.
本研究的主要目的是调查对白化豚鼠进行体内高压氧（HBO）治疗，对其眼屈光状态、晶状体体外光学特性以及晶状体线粒体完整性的影响。动物接受HBO治疗30 - 35次（2.5 - 3个月）或70次（6个月）。在30次治疗时，裂隙灯检查显示晶状体核光散射水平增加，70次治疗时这种增加更明显。在两项分别由不同验光师进行的独立研究中，发现经过30 - 35次HBO治疗后，眼睛的屈光状态出现近视性偏移。此外，35次HBO治疗后晶状体的平均后顶点距离显著缩短，而70次治疗后球差（焦点变化）增加。70次HBO治疗后未观察到屈光状态的差异（初始近视效应逆转）。35次和70次HBO治疗后，晶状体上皮和浅层皮质纤维细胞的线粒体分布和形态均正常，这突出表明HBO治疗不影响晶状体的浅层皮质。本研究中进行的晶状体体外光学分析结果与体内30 - 35次HBO治疗后观察到的近视相关。已知长期接受HBO治疗的人类也会出现类似的可逆性近视和晶状体核光散射增加，结果表明近视是由晶状体折射率变化引起的。70次HBO治疗后明显的焦点清晰度丧失可能与先前关于成熟豚鼠中HBO诱导的晶状体核透明度丧失相关的生化和形态学变化的报道有关。豚鼠HBO模型可能是研究晶状体发育和屈光不正的一种有用方法。
