摘要
目的 比较SRK T(Sanders Retzlaff KvaffT)和SRK Ⅱ (Sanders Retzlaff KvaffⅡ )公式的特点 ,以提高高度近视白内障患者人工晶状体 (intraocularlens ,IOL)屈光度数计算的准确性。方法 (1)使用相同的生物参数 (眼轴长度和角膜屈光力 )和A常数 ,比较SRK T和SRK Ⅱ公式理论计算值的差异 ;(2 )对 86例 (130只眼 )高度近视白内障患者行超声乳化白内障吸除联合IOL植入术。分别采用SRK T和SRK Ⅱ公式计算IOL屈光度数 ,记录并比较不同眼轴长度患者按照两公式计算结果植入IOL术后实际屈光度数与预期屈光度数的差异。随访时间 3～ 2 4个月。结果 (1)角膜屈光力为 4 3 0 0D时 ,两公式理论计算值比较差异无显著意义 (P >0 0 5 ) ,且两公式计算的屈光度数差值与眼轴长度无相关 (P>0 0 5 ) ;角膜屈光力为 39 0 0、4 1 0 0、4 5 0 0及 4 7 0 0D时 ,两公式理论计算值比较差异均有显著意义(P <0 0 5 ) ,且两公式计算的屈光度数差值与眼轴长度呈中、高度线性正相关 (P <0 0 5 )。(2 )按照SRK T和SRK Ⅱ公式计算结果植入IOL术后 ,术眼实际屈光度数与预期屈光度数差值分别为 0 0 8D和 -0 79D ,差异有显著意义 (P <0 0 5 )。结论 选择IOL屈光度数的计算公式 ,应综合考虑患者的眼轴长度和角膜屈光力等因素 ;
Objective To compare the accuracy of two IOL power formulas (SRK-T and SRK-Ⅱ) in order to improve the accuracy of predicative IOL powers for patients with cataract and high myopia. Methods (1) Patient′s axial lengths of the eye, K-readings and A-constants were input to the SRK-T and SRK-Ⅱformulas. The differences in predicative refraction between the two formulas were compared. (2) Eight six patients (130 eyes) with cataract and high myopia underwent phacoemulsification and posterior chamber IOL implantation were studied. These patients were randomly divided into two groups and received IOL whose power was determined by either SRK-T or SRK-Ⅱ. Three months after IOL implantation, the postoperative refractions were recorded and compared with predictive refractions. Patients were followed-up for 3 to 24 months. Results (1) When K-reading was 43.00 D, there was no statistically significant difference between the results from these two formulas ( P >0.05) and there was no correlation between the difference and the axial lengths ( P >0.05). In eyes with K-reading at 39.00 D, 41.00 D, 45.00 D, or 47.00 D, there was statistically significant difference between the results from these two formulas ( P <0.05). The difference between the two formulas was in proportional to the axial length ( P <0.05). (2) The mean error between the postoperative refraction and predictive refraction determined by SRK-T and SRK-Ⅱ formula was 0.08 D and -0.79 D, respectively. The difference between these two formulas was statistically significant ( P <0.05). Conclusion Selection of IOL power formula should consider the axial length, K-reading and other related factors. SRK-T formula is appropriate for high myopia eyes with axial length longer than 26.0 mm. In this group, SRK-T formula is much more accurate than the SRK-Ⅱ formula.
出处
《中华眼科杂志》
CAS
CSCD
北大核心
2003年第5期290-293,共4页
Chinese Journal of Ophthalmology
