视网膜潜视力测定在高度近视白内障患者术前的应用

Examination of preoperative potential visual acuity before operation for cataract patients with high myopia

目的评估高度近视白内障患者术前视网膜潜视力(PVA)测定的可靠性。并与术后3个月的最佳矫正视力(BCVA)作比较。方法高度近视白内障患者95例102眼,术前应用视网膜计检测术眼的PVA。根据PVA值,将患者分为两组:A组,术前PVA≤20/60,45例49眼;B组,术前PVA>20/60,50例53眼。结果术前PVA与术后3个月BCVA基本一致者54眼,一致率为52.9%。术前PVA与术后3个月BCVA差异大者31眼(30.4%):25眼为假阴性,其中16眼晶状体混浊度为Ⅲ～Ⅳ级;6眼为假阳性,其中2眼为视网膜脱离刚复位,3眼为黄斑区色素上皮萎缩灶,1眼为角膜不规则。A组术前PVA与术后3个月BCVA基本一致者18眼(36.7%),差异大者26眼(占53.1%);B组术前PVA与术后3个月BCVA基本一致者36眼(67.9%),差异大者仅5眼(9.4%);A组术前PVA与术后3个月BCVA的偏差显著大于B组(P<0.01)。结论LAMBDA100视网膜计能比较准确地反映高度近视白内障患者视网膜黄斑区的视功能状态,对PVA≤20/60者,应结合其他临床检查作出评价,以减少预测偏差。

Objective To evaluate the reliability of preoperative retinometer in predicting the potential visual acuity （PVA）of cataract patients with high myopia. Methods Using retinometer （LAMBDA100）, we measured the PVA on 102 eyes of 95 patients with high myopia before cataract surgery. Patients were divided into two groups： group A （49 eyes in 45 patients） with PVA ≤20/60; group B （53 eyes in 50 patients） with PVA〉20/60. The PVA was compared with the best corrected visuai acuity （BCVA） 3 months after operation. Results PVA showed good consistence with the postoperative BCVA in 54 eyes （52.90%）. The PVA of 31 eyes （30.4%） were significantly different from their corresponding BCVA; 24 of the 31 eyes were false-negative： 16 eyes had grade Ⅲ or Ⅳ lens opacity. Six of the 31 eyes were false-positive： 2 eyes had retinal detachment surgery just before the study, 3 had RPE atrophy in macular area, and one had irregular cornea. In group B 36 eyes （67.9%） were well consistent with the postoperative BCVA ; only 5 eyes （9.4 % ） showed great difference between PVA and post-operative BCVA. In group A the PVA of 26 eyes （53.1%） were significantly different compared with the postoperative BCVA only 18 eyes （36.7 % ） showed good consistence. The PVA and post-operative BCVA of group A were significantly different from those of group B （P〈0.01）. Conclusion LAMBDA 100 potential acuity is relatively reliable to predict the postoperative visual acuity of cataract patients with high myopia. Patients with PVA less than 20/60 needs further examination to avoid errors.