硅油填充眼A超眼轴测算及人工晶状体度数计算

Eye axis measurement with A-ultrasonic scan and the calculation of the power of intraocular lens in silicone oil-filled eyes

目的:评价声速调整法测量硅油眼眼轴、测算人工晶状体度数的准确性。方法:对2003/2008年于我院治疗的24例硅油填充术后并发性白内障患者,采取坐位眼轴测量并改变硅油眼中超声波的传播速度来修正眼轴长度,再将计算所得眼轴长度代入SRKII公式计算拟植入的人工晶状体度数。行硅油取出术联合白内障摘除+人工晶状体植入术。术后3mo测量眼轴及屈光状态。对手术前后眼轴长度进行对比,将术后屈光状态与术前预期值比较。结果:硅油取出术前平均眼轴长度为25.25±0.65mm,术后平均眼轴长度为24.80±0.67mm,取油前后眼轴长度均值差异无统计学意义。手术后屈光度与术前预期值差值平均为1.50±0.40D,差异无统计学意义。结论:通过坐位测量并调整超声波在硅油中的传导速度,可准确测量硅油填充眼眼轴,较传统方法测算人工晶状体度数准确率更高。

AIM： To evaluate the accuracy of modified sound speed for the measurement of eye axis and the power of intraocular lens（IOL） in silicone oil-filled eye. METHODS： Twenty-four cases with cataract after silicone oil tamponade from 2003 to 2008 in our hospital were included. The eye axis length were measured with A-ultrasonic scan and calculated by the sound speed modified formula. The power of IOL were then calculated through SRK II formula. All cases underwent the operation of silicone oil removal combined with phacoemulsification and IOL implantation. 3 months after surgery all eyes were reexamined and the actual axial length were again measured. The eye axis length and the refraction state were compared before and after the operation. RESULTS： The eye axis length was 25. 25 ± 0. 65mm before silicone oil tamponade and 24.80 ± 0.67mm after the operation. And the postoperative eye axis length measurements showed no statistical significance compared with the preoperative measurement. The mean difference of the refraction state before and after the operation was 1.50 ± 0.40D, and the difference was not significant. CONCLUSION： Eye axis lens measurement with Aultrasonic scan by modified sound speed shows better clinical practicability in silicone oil-filled eyes than traditional manual counting method.