角膜厚度与高眼压症及青光眼的眼压

Corneal thickness and intraocular pressure in cases with ocular hypertension and glaucoma

目的 探讨高眼压症、正常眼压性青光眼、原发性开角型青光眼患者及正常人的角膜厚度差异 ,分析角膜厚度与眼压间的关系 ,以及角膜厚度的测定对各型青光眼的诊断意义。方法 用超声波角膜测厚仪检测 73例 (73只眼 )高眼压症、79例 (79只眼 )正常眼压性青光眼、6 1例 (6 1只眼 )原发性开角型青光眼患者与 5 0例 (5 0只眼 )正常人的中央角膜厚度 ,并将其测定结果进行比较。回顾性分析每只青光眼治疗前的最高眼压 (Goldmann) ,包括 2 4h眼压曲线 ,用Ehler法通过中央角膜厚度对眼压进行校正。结果 正常组的中央角膜厚度值变异幅度较大 ,与压平眼压值呈正相关 (r =0 42 3,P =0 0 0 4)。高眼压症组、正常眼压性青光眼组、原发性开角型青光眼组及正常组的中央角膜厚度分别为 (5 82± 32 ) μm、(5 48± 33) μm、(5 5 0± 33) μm及 (5 5 2± 36 ) μm ,高眼压症组的中央角膜厚度值明显高于正常组和各型青光眼组 (P <0 0 0 1) ;各组与正常组比较 ,差异无显著性 (P >0 0 5 )。各组矫正后眼压均低于矫正前眼压。矫正后眼压≤ 2 1mmHg(1mmHg =0 133kPa)的眼数分别占正常人、正常眼压性青光眼、高眼压症及原发性开角型青光眼患者总数的 10 0 %、97%、5 5 %和 5 0 %。

Objective To investigate the relationship between central corneal thickness (CCT) and intraocular pressure (IOP) in patients with ocular hypertension (OH), normal tension glaucoma (NTG), primary open angle glaucoma (POAG) and normal subjects and the importance of CCT in the diagnosis of glaucoma. Methods The CCT was measured in 79 cases with NTG, 61 POAG, 73 OH and 50 normal subjects with an ultrasonic pachymeter. One eye in one subject randomly selected was used for inter-group comparison. The maximum IOP measured by Goldmann applanation tonometer without ocular hypotensive therapy during the follow-up was corrected with CCT by using Ehlers′ method. Results The CCT of OH subjects (582±32) μm was significantly thicker than that of other groups ( P <0.001), while no differences were seen in CCT among normal, NTG and POAG groups, the thickness being (552±36) μm, (548±33) μm and (550±33) μm respectively. The corrected maximum pressure was significantly lower than that in the untreated ones in all the groups, and ≤21 mm Hg in 100%, 97%, 55% and 50% of the eyes in the normal, NTG, OH and POAG subjects, respectively. In the normal subjects, the CCT was positively correlated with the IOP ( r =0.423, P =0.004). Conclusions There is a large variation in CCT of normal subjects, which is significantly positively correlated with IOP. The CCT is significantly thicker in OH subjects, which should be considered as an important variable in follow-up. No significant differences in CCT are shown among NTG, POAG and normal groups. It is suggested that CCT has little influence on the diagnosis of NTG and POAG.