Hamilton Kirsten Elizabeth, Pye David Cecil, Aggarwala Shivani, Evian Sindy, Khosla Joti, Perera Rachithri
School of Optometry and Vision Science, University of New South Wales, Sydney NSW 2052, Australia.
J Glaucoma. 2007 Jan;16(1):29-35. doi: 10.1097/IJG.0b013e31802b350f.
To determine whether there is a temporal relationship between the diurnal variation of central corneal thickness (CCT) and intraocular pressure (IOP) by Goldmann applanation tonometry in young normal human participants in vivo.
Twenty-five eyes of 25 young healthy normal participants were examined in a prospective observational cross-sectional study. IOP, CCT and corneal curvature were measured using standard clinical techniques over a 24-hour period, and the temporal interrelationships between these parameters were examined.
The overnight change in IOP measured by Goldmann tonometry was 3.1+/-2.4 mm Hg (P<0.001), CCT was 20.1+/-10.9 mum (P=0.016), with no statistical change in central corneal curvature (0.05 mm, P=0.477, paired t test with Bonferroni correction). Both IOP and CCT were highest on awakening at 7:00 then dropped rapidly to baseline levels by 9:00 (linear mixed models), and these two parameters were highly correlated (r=0.978, P<0.001). After 9:00, there was no correlation between these parameters (r=-0.453, P=0.260).
The results of this study have highlighted a potential link between the diurnal variation of CCT and the accuracy of Goldmann tonometry estimates of IOP during the first 2 hours after awakening. Clinicians should be wary of using Goldmann tonometry to estimate IOP until the overnight increase in CCT has resolved.
通过Goldmann压平眼压计测定年轻正常人类受试者活体中央角膜厚度（CCT）与眼压（IOP）的昼夜变化之间是否存在时间关系。
在一项前瞻性观察性横断面研究中，对25名年轻健康正常受试者的25只眼睛进行了检查。在24小时内使用标准临床技术测量眼压、中央角膜厚度和角膜曲率，并检查这些参数之间的时间相互关系。
通过Goldmann眼压计测量的眼压夜间变化为3.1±2.4 mmHg（P<0.001），中央角膜厚度为20.1±10.9μm（P=0.016），中央角膜曲率无统计学变化（0.05 mm，P=0.477，采用Bonferroni校正的配对t检验）。眼压和中央角膜厚度在早上7点醒来时最高，然后在9点迅速降至基线水平（线性混合模型），这两个参数高度相关（r=0.978，P<0.001）。9点之后，这些参数之间无相关性（r=-0.453，P=0.260）。
本研究结果突出了中央角膜厚度的昼夜变化与觉醒后最初2小时内Goldmann眼压计眼压估计准确性之间的潜在联系。在中央角膜厚度的夜间增加消退之前，临床医生在使用Goldmann眼压计估计眼压时应谨慎。
