超声乳化白内障吸除术后泪膜的变化

Tear film changes after phacoemulsification

目的 了解超声乳化白内障吸除术对泪膜的影响。方法 随机抽取行超声乳化白内障吸除术的老年性白内障患者 6 8例 (79只眼 ) ,分别于术前 ,术后 1、2、7、14、30及 180d行泪膜破裂时间(breakuptime ,BUT)、基础泪液分泌试验 (SchirmerⅠtest,SⅠt)、角膜荧光素染色、干眼仪检查及下睑中央泪河高度检查。结果 与术前相比 ,术后 1及 2d ,BUT明显缩短 ,SⅠt、下睑中央泪河高度、角膜荧光素染色程度及干眼仪检查等级明显增高 (P <0 0 1) ;术后 7d时SⅠt,14d时下睑中央泪河高度 ,30d时BUT、角膜荧光素染色程度和干眼仪检查等级恢复至术前水平 ,与术前比较差异无显著意义(P >0 0 5 )。术后 30d ,19 3%的患眼泪膜未能恢复至术前水平 ;术前泪膜正常的患者中 1/9发生干眼。术后 1、7、14及 30d ,术前BUT <10s的术眼BUT <5s的发生率高于术前BUT≥ 10s的术眼(P <0 0 5 ) ;术后 14、30及 180d ,术前角膜荧光素染色评分 >2分的术眼术后角膜荧光素染色评分 >2分的发生率高于术前角膜荧光素染色评分≤ 2分的术眼 (P <0 0 5 ) ;术后 14d ,术前干眼仪检查等级≥Ⅲ级的术眼术后干眼仪检查等级≥Ⅲ级的发生率高于术前干眼仪检查等级 <Ⅲ级的术眼(P <0 0 5 )。结论 超声乳化白内障吸除术可影响泪膜的稳定性 。

Objective To evaluate tear film changes after phacoemulsification Methods This prospective randomized study involved 68 consecutive patients with age related cataract (79 eyes) who underwent phacoemulsification Tear break up time, Schirmer Ⅰ test (SⅠt) value, corneal fluorescein staining, tear film pattern by DR 1 tear interfermetry and the height of tear meniscus were measured preoperatively and 1 day and 2, 7, 14, 30, 180 days postoperatively Results At 1 day and 2 days postoperatively, the mean tear break up time reduced greatly, and the number of patients who showed Ⅲ to Ⅴ tear film pattern, the mean SⅠt value, the height of tear meniscus and fluorescein staining scores increased significantly ( P <0 001 for day 1, P <0 005 for day 2) SⅠt value at 7 days postoperatively ( P =0 831) and the height of tear meniscus at 14 days returned to their preoperative values ( P =1 000) The tear break up time, corneal fluorescein staining scores and the grades of tear film pattern all recovered at 30 days postoperatively ( P >0 05) At 30 days postoperatively, 19 3% of patients showed shorter tear break up time and less SⅠt value than that of preoperative day In addition, 1/9 of the patients with normal preoperative tear film experienced dry eye at 30 days postoperatively The cases with tear break up time <10 seconds compared to patients with tear break up time ≥10 seconds were more easily to show tear instability postoperatively (relative risk 13 5, 8 25, 20 0, 39 0, 8 6, 3 9 at 1 day and 2, 7, 14, 30, 180 postoperative days, respectively) Conclusion Phacoemulsification significantly alters the tear break up time, SⅠt value, corneal fluorescein staining, tear film pattern and the height of tear meniscus Some patients with normal tear film may experience dry eye after surgery Patients with preexisting tear break up time <10 seconds are easily at risk of experiencing the tear film instability postoperatively