Realini Tony, Weinreb Robert N, Hobbs Gerald
Department of Ophthalmology, West Virginia University, Morgantown, WV, USA.
J Glaucoma. 2009 Feb;18(2):119-23. doi: 10.1097/IJG.0b013e31817d23c7.
To compare intraocular pressure (IOP) values measured by both Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) in both normal and glaucomatous eyes, and to determine the relationship between these parameters and central corneal thickness (CCT).
Forty-seven subjects with primary open-angle glaucoma and 38 normal subjects attended a 12-hour session during which IOP was assessed at 7 time points, every 2 hours, by both GAT and DCT. CCT was also assessed at the same visit. Mean IOP was calculated for each eye of each subject by each method from the 7 diurnal IOP measurements obtained.
Mean IOP was higher when measured by DCT than by GAT in both normal (by 1.1 mm Hg, P<0.0001) and glaucomatous (by 1.6 mm Hg, P<0.0001) eyes. IOP measurements by GAT and DCT were moderately correlated in both normal (r(2)=0.354, P<0.0001) and glaucomatous (r(2)=0.552, P<0.0001) eyes. In normal eyes, there was a weak positive correlation between GAT IOP and CCT (r(2)=0.088, slope=0.022 mm Hg/microm, P=0.009) and no correlation between DCT IOP and CCT (r(2)=0.007, slope=0.005 mm Hg/microm, P=0.468). In glaucomatous eyes, there was no correlation between GAT IOP and CCT (r(2)=0.006, slope=0.007 mm Hg/microm, P=0.473) and a weak inverse correlation between DCT IOP and CCT (r(2)=0.075, slope=-0.021 mm Hg/microm, P=0.008).
Both GAT and DCT are affected by CCT, albeit in different ways. Normal and glaucomatous eyes exhibit different relationships between CCT and IOP measured by either GAT or DCT. The relationships between CCT and transcorneal IOP measurements are complex and incompletely characterized, which limits the clinical interpretation of GAT and DCT measurements of IOP in both normal and glaucomatous eyes.
比较正常眼和青光眼眼中通过Goldmann压平眼压计（GAT）和动态轮廓眼压计（DCT）测量的眼压（IOP）值，并确定这些参数与中央角膜厚度（CCT）之间的关系。
47例原发性开角型青光眼患者和38例正常受试者参加了一个12小时的实验，在此期间，每2小时通过GAT和DCT在7个时间点评估眼压。在同一次就诊时也评估中央角膜厚度。根据获得的7次日间眼压测量值，用每种方法计算每个受试者每只眼睛的平均眼压。
在正常眼（高1.1 mmHg，P<0.0001）和青光眼眼（高1.6 mmHg，P<0.0001）中，通过DCT测量的平均眼压均高于通过GAT测量的平均眼压。在正常眼（r(2)=0.354，P<0.0001）和青光眼眼（r(2)=0.552，P<0.0001）中，GAT和DCT测量的眼压呈中度相关。在正常眼中，GAT眼压与中央角膜厚度之间存在弱正相关（r(2)=0.088，斜率=0.022 mmHg/μm，P=0.009），而DCT眼压与中央角膜厚度之间无相关性（r(2)=0.007，斜率=0.005 mmHg/μm，P=0.468）。在青光眼眼中，GAT眼压与中央角膜厚度之间无相关性（r(2)=0.006，斜率=0.007 mmHg/μm，P=0.473），而DCT眼压与中央角膜厚度之间存在弱负相关（r(2)=0.075，斜率=-0.021 mmHg/μm），P=0.008）。
GAT和DCT均受中央角膜厚度影响，尽管方式不同。正常眼和青光眼眼在中央角膜厚度与通过GAT或DCT测量的眼压之间表现出不同的关系。中央角膜厚度与经角膜眼压测量值之间的关系复杂且特征不完全明确，这限制了在正常眼和青光眼眼中GAT和DCT眼压测量值的临床解读。
