视网膜计对白内障术后视力预测可靠性评价及相关影响因素分析

目的为了客观评价视网膜计对白内障患者潜视力预测的准确率、找出影响准确率的相关因素和指导其临床应用。方法对拟手术患者600例白内障患者在手术前用视网膜计对患者的潜在视力(手术后可能达到的视力)进行预测,手术后对其视力复查。并以第2周时做验光矫正后所达到的最佳视力为准。结果判定标准:相符:手术后2周所达视力与手术前预测一致或相差一行对数视力者;基本相符:手术后视力与手术前预测相差2行者;不符:手术后视力与手术前预测相差2行以上者。结果600眼中其中手术前预测与手术后实际最佳矫正视力相符者85眼占14.17%,基本相符者339眼占56.50%,不符合者176眼,占29.33%,总体符合率为70.67%。其中107眼超度高近视眼中符合与基本符合相加所占比例高达93.46%。结论视网膜计具有预测方法简便,检查时间短,结果符合率较高,有较高的参考价值,可以作为白内障手术前常规检查项目。影响其准确率的因素主要有:成熟期、IV级以上硬度核白内障因光栅的透过性差而直接影响患者的分辨能力和测试准确度。高龄、弱智、不合作者也是相关因素。

Clinical Assessment and analyse on the Retinometer Prediction of Post-surgical Vision in Patients with Cataracts

Objective Evauate the clinical outcome of the retinometer prediction on the potential best post-surgical vision in patients with cataracts, and identify the common encountered factors which may affect the accuracy of such an examination. Methods Six hundreds of patients with cataracts were examined with retinometer during routine pre-surgical eye examination for the potential best vision after the surgery. The surgical procedures were all based on phacoemulsification cataract extracts plus IOLs implantation. Two weeks opst-surgery, the best corrected visual acuities were compared against the prdeictions. The log E chat was used for recording all the vision. Good prediction was marked if the real post-surgical vision was one line different from the prediction. Fair prediction meant that the difference were two lines. Any prediction which differed from the actual post-surgical vision by three lines and more was considered failure. Results Among the 600 cases, 85 (14.17%) eyes could see as good as the predicted vision before the surgery (good prediction). The majority of the patients (339 eyes or 56.5.%) were in the fair prediction group.These two groups count for 70. 67% out of the patients involved. On the other hand, the prediction in 176 cases (29.33%) failed. In the group of high myopia (107 eyes), the percentage of good prediciton plus fair prediction was significantly higher (93. 46%). The poor predictions were more often in the patients with matured cataract or with a grade IV nuclear density. Conclusion Considering the simple, safe and convenience of Retinometer procedure, as well as its acceptable percentage of the cases involved, the procedure can be included in the routine pre-surgical eye ex- amination for cataract patients. Maturity of cataract, the nuclear density and the length of the eyeball can affect the prediction, and further study should be conducted to get the weight for each of the factors in the prediction.A formula will be generated based on those studies to establish a way to correct the simple prediction so that more cataract patients can be informed ablut the potential post-surgical vision.