彩色多普勒超声对高度近视眼后巩膜改变相关因素的评价

Correlation factors in changes of rear sclera in high myopia evaluated by color Doppler ultrasound

目的：探讨高度近视眼后巩膜形态改变与眼轴长度、近视程度及血流动力学变化之间的关系。方法：应用ATL超9型APOOGE-800型彩色多普勒超声诊断仪，探头频率5．0—10．0MHz。对26例正常眼，36例轻中度近视眼，51例高度近视眼后巩膜进行观察。并对26例正常眼，17例轻中度近视眼，26例高度近视眼的眼动脉（OA）、视网膜中央动脉（CRA）、睫状后动脉（PCA）进行检测。结果：轻中度近视组、高度近视组的眼轴长度与近视程度呈正相关性。两者之间的直线回归方程Y=-3510．3＋1668．1X，R=0．9432，P〈0．0001。后巩膜形态改变与正常对照组比较差异有显著性意义（P〈0．001）。高度近视眼组、轻中度近视组与正常对照组比较，OA血流参数差异无显著性意义（P〉0．05），而高度近视组的CRA、PCA的收缩期（PSV）、舒张期（EDV）、平均血流速度（AV）均减低，CRA的阻力指数（RI）升高（P〈0．05）。轻中度组与对照组比较差异无显著性意义（P〉0．05）。结论：视网膜血管、睫状血管系统血供不足与后巩膜形态变化的类型、眼轴长度、近视的程度及血流动力学改变密切相关，是引起高度近视眼病理性眼底改变发生和发展的重要因素。

Objective：To explore the morphological changes of rear sclera in myopia and the relation among the length of eye axis and the degree of myopia and hemodynamic changes. Methods： Morphology of rear sclera in 26 cases of normal control （NC）, 36 cases of light and medium myopia （LAMM） and 51 cases of high myopia （HM） were observed by color Doppler ultrasound. And ophthalmic artery （OA）, central retinal artery （CRA） and posterior ciliary artery （PCA） in NC group, 17 cases of LAMM group and HM group were measured. Results：The length eye axis in LAMM group and HM group had positive correlation with the degree of myopia. The linear regression equation between them was Y = -3510.3 ＋ 1668. IX, R = 0.9432, P 〈 0.0001. The morphological changes of rear sclera in both LAMM group and HM group had significant difference compared with that in NC group （ P 〈 0.0001）. The flow parameters of OA in each group had no significant difference compared with that in other groups （ P 〉 0.05）. The systolic, diastolic and mean flow velocity of CRA,PCA in HM group decreased significantly （ P 〈0.05） ,but the resistent index （RI） of CRA in HM group increased significantly （ P 〈 0.05）. The flow parameters in LAMM group had no significant difference as compared with that in NC group （ P 〉 0.05）. Conclusion： The insufficient blood supply to retina is an important factor that contributes to the occurrence and development of the pathological changes of retina in high myopia. The type of morphological changes in rear sclera shows significant correlation with the length of eye axis, the degree of myopia and hemodynamic changes.