摘要
目的探讨2种不同的角膜曲率(K值)修正方法,对高度近视角膜屈光术后的白内障患者在接受白内障超声乳化及人工晶状体(intraocular lens,IOL)植入术时的IOL屈光度数计算的准确性进行比较。方法自2005年11月至2008年1月,在我院接受白内障超声乳化及IOL植入手术并曾行角膜屈光术的高度近视白内障患者13例(21眼),全部病例均可获得角膜屈光手术前的K值及手术前、后稳定的屈光度。使用临床病史调查法(clinical history method,CHM)及Shammas等得出的K值修正公式(简称S公式)分别对K值进行修正,从而得到K修正值,利用第3代IOL计算公式——SRK/T公式计算IOL的屈光度(预期屈光度值为-0.50D左右),统一采用CHM所得的计算结果实行手术,同时将S公式推算所得的IOL屈光度与实际植入的IOL度数进行比较,从而推算出术后预期屈光度值。根据术后实际屈光度值与CHM、S公式的预期屈光度值相比较,以评价2种方法的准确性。结果21眼视力均明显提高,术后等效球镜度数:-1.00^-0.50D者1眼,-0.50~0.00D者4眼,0.00^+0.50D者13眼,+0.50^+1.00D者3眼。实际屈光度值与CHM所测屈光度值间的误差最小,为-0.50^+1.50D,与S公式差值为+0.50^+3.00D。结论曾行角膜屈光手术的高度近视白内障患者欲行白内障超声乳化手术治疗,计算IOL度数时,应以CHM为首选,若无法获取临床资料,则可酌情使用S公式。
Objective To investigate and compare the accuracy of two different ways for adjusting corneal curvature（K value）in calculating intraocular lens（IOL）diopter at patients,who were with high myopia and developed cataract after corneal refractive surgery,in phacoemulsification and IOL implantation.Methods Thirteen patients（21 eyes）,who were with high myopia and developed cataract after corneal refractive surgery,were taken phacoemulsification and IOL implantation in our hospital from November 2005 to January 2008.All patients were measured the K value before corneal refractive surgery and the stable diopter before and after surgery. Adjustment formula of K value was achieved by clinical history method（CHM） and Shammas（S formula） to correct K value, respectively, and get the allowance of K value. IOL diopter was measured by SRK/T, the third IOL formula, and the predictive diopter was about - 0.50 D. The surgery was taken according to the calculation results by CHM, and IOL diopter calculated by S formula and the actual IOL degree for implantation were compared to get predictive diopter postoperatively. The accuracies of two different ways were evaluated by comparing the predictive diopter by CHM or S formula with actual diopter. Results The visual acuity of 21 eyes were obviously improved. Postop- erative spherical equivalent were - 1.00 D to -0.50 D in 1 eye, -0.50 D to 0 in 4 eyes（ 19.05% ） ,0 to ＋0.50 D in 13 eyes （61.90%） and ＋0.50 D to＋ 1.00 D in 3 eyes（ 14,29% ）. The error between actual diopter and predictive diopter by D/-/M was less with - 0.50 D to ＋ 1.50 D than ＋ 0.50 D to ＋ 3.00 D between acutal diopter and predictive diopter by S fromula. Conclusion CI-IM is the first choice to calculate IOL diopter in patients, who are with high myopia and developed cataract after corneal refractive surgery, in phacoemulsification and IOL implantation. S formula can be taken when the clinical data can＇ t be achieved by CHM.
出处
《眼科新进展》
CAS
北大核心
2009年第12期943-945,共3页
Recent Advances in Ophthalmology
