巩膜环扎外加压术对角膜前表面屈光性状的影响

目的探讨巩膜环扎外加压术后角膜前表面屈光性状改变的规律.方法采用前瞻性自身对照研究,对30例(30眼)因孔源性视网膜脱离接受巩膜环扎外加压术的患者在术前l d、术后1周、1个月和3个月,分别用OrbscanⅡ角膜地形图仪检测术眼的角膜前表面屈光度、散光度、散光轴向和不规则散光度,并分析不同手术因素对角膜前表面屈光性状的影响.结果巩膜环扎外加压术引起角膜前表面周边部术后1周屈光度显著减小(P＜0.01);中央部散光度显著增加;散光轴向向加压块中点轴向偏移,术后1周中央部与术前比较差异具有显著性(P＜0.05);不规则散光度变化差异无显著性.手术中环扎带的长度和加压块的宽度与各屈光参数的变化有显著相关性.结论巩膜环扎外加压术后的角膜前表面屈光改变以短期为主.医生在手术操作中应尽量减小对角膜形状的改变,以保证术后的视觉恢复.

Anterior corneal topographic changes after scleral buckling surgery

OBJECTIVE: To investigate corneal refractive changes after scleral buckling surgery. METHODS: In a prospective self-controlled clinical study, we investigated the changes of refractive power, astigmatic power, astigmatic axis, and irregular astigmatic power of anterior corneal surface following scleral buckling surgery for retinal detachment in 30 patients (30 eyes). The corneal shapes were detected by Orbscan II topography at 1 day before surgery, and 1 week, 1 month, and 3 months after surgery. The effects of some surgical factors on the anterior corneal refractive changes were analyzed. RESULTS: After surgery, refractive power on corneal anterior surface decreased significantly in peripheral zone at 1 week (P < 0.01). Astigmatic power increased obviously in central zone. The direction of astigmatic axis matched the direction of the buckle, and changed obviously in central zone after 1 week (P < 0.05). Irregular astigmatic power did not change significantly. There was a significant correlation between the encircling length/the buckle width and the refractive changes of corneal anterior surface. CONCLUSION: Refractive changes of corneal anterior surface following scleral buckling surgery was mainly temporary. Changes in the shape of corneal should be minimized to ensure a favorable postoperative visual acuity.