Emara B, Probst L E, Tingey D P, Kennedy D W, Willms L J, Machat J
Windsor Laser Center, Ontario, Canada.
J Cataract Refract Surg. 1998 Oct;24(10):1320-5. doi: 10.1016/s0886-3350(98)80222-8.
To determine the relationship of intraocular pressure (IOP) and central corneal thickness (CCT) in normal myopic eyes and after laser in situ keratomileusis (LASIK).
TLC The Windsor Laser Center, Windsor, Ontario, Canada.
Intraocular pressure measured by Goldmann applanation tonometry and CCT by ultrasonic pachymetry were determined in a group of untreated corneas of 120 patients (203 eyes) and in 50 patients (85 eyes) pre- and post-LASIK. Statistical analyses were performed with the Pearson correlation coefficient and paired Student t test.
In the untreated group of 288 eyes, mean CCT was 544.0 microns +/- 37.3 (SD) (range 461 to 664 microns) and mean IOP, 15.6 +/- 2.7 mm Hg (range 10 to 24 mm Hg). The correlation between IOP and CCT in this group was highly significant (r = 0.44; P < .0001). The slope was 0.032 mm Hg/micron of CCT or an approximate decrease of 1 mm Hg, for a reduction in CCT of 31.3 microns. In the post-LASIK group, mean CCT dropped approximately 73.0 microns to 479.5 +/- 41.2 microns (range 408 to 503 microns) and IOP dropped to a mean of 13.6 +/- 3.3 mm Hg (range 7 to 22 mm Hg). A significant correlation was found between IOP and CCT after LASIK (r = 0.33; P < .002). The difference between the mean pre- and post-LASIK measurements of applanation IOP was 2.5 mm Hg, which was significant (P < .0001). The post-LASIK slope was 0.027 mm Hg/micron, or a decrease of 1.0 mm Hg per 37.8 microns reduction in CCT.
Central corneal thickness is an important variable in the evaluation of applanation IOP and should be included in the assessment of any case of potential glaucoma or ocular hypertension, particularly in eyes with previous photoablative refractive surgery.
确定正常近视眼中眼压（IOP）与中央角膜厚度（CCT）之间的关系，以及准分子原位角膜磨镶术（LASIK）术后二者的关系。
加拿大安大略省温莎市的TLC温莎激光中心。
采用Goldmann压平眼压计测量眼压，超声测厚仪测量120例患者（203只眼）未经治疗的角膜以及50例患者（85只眼）LASIK术前和术后的中央角膜厚度。采用Pearson相关系数和配对t检验进行统计分析。
在288只未经治疗的眼中，平均中央角膜厚度为544.0微米±37.3（标准差）（范围461至664微米），平均眼压为15.6±2.7毫米汞柱（范围10至24毫米汞柱）。该组中眼压与中央角膜厚度之间的相关性非常显著（r = 0.44；P <.0001）。斜率为每微米中央角膜厚度0.032毫米汞柱，即中央角膜厚度减少31.3微米时，眼压大约降低1毫米汞柱。在LASIK术后组中，平均中央角膜厚度下降约73.0微米，至479.5±41.2微米（范围408至503微米），眼压降至平均13.6±3.3毫米汞柱（范围7至22毫米汞柱）。LASIK术后眼压与中央角膜厚度之间存在显著相关性（r = 0.33；P <.002）。LASIK术前和术后压平眼压测量值的平均差值为2.5毫米汞柱，具有显著性（P <.0001）。LASIK术后斜率为0.027毫米汞柱/微米，即中央角膜厚度每减少37.8微米，眼压降低1.0毫米汞柱。
中央角膜厚度是评估压平眼压时的一个重要变量，在评估任何潜在青光眼或高眼压症病例时都应予以考虑，尤其是在既往有屈光性角膜切削手术史的眼中。
