Department of Ophthalmology, Weill Cornell Medical College, 1305 York Avenue, New York, NY 10021, USA.
BMC Ophthalmol. 2012 Sep 25;12:52. doi: 10.1186/1471-2415-12-52.
To better understand the role of corneal properties and intraocular pressure (IOP) in the evaluation of primary open-angle glaucoma (POAG); and to determine the feasibility of identifying glaucomatous optic neuropathy (GON) using IOP corrected and uncorrected for corneal biomechanics.
Records from 1,875 eyes of consecutively evaluated new patients were reviewed. Eyes were excluded if central corneal thickness (CCT) or Ocular Response Analyzer (ORA) measurements were unavailable. Presence or absence of GON was determined based on morphology of the optic disc, rim and retinal nerve fiber layer at the time of clinical examination, fundus photography and Heidelberg Retinal Tomography. Goldmann-applanation tonometry (GAT) in the untreated state was recorded and Goldmann-correlated (IOPg) and corneal-compensated IOP (IOPcc) were obtained using the ORA. Glaucomatous eyes were classified as normal or high-tension (NTG, HTG) using the conventional cutoff of 21 mm Hg. One eligible eye was randomly selected from each patient for inclusion.
A total of 357 normal, 155 HTG and 102 NTG eyes were included. Among NTG eyes, IOPcc was greater than GAT (19.8 and 14.4 mm Hg; p < 0.001) and the difference between IOPcc and GAT was greatest for this subgroup of patients with NTG (p ≤ 0.01). The maximum combined sensitivity and specificity for detection of GON occurred at 20.9 mm Hg for GAT (59%, 90%) and 18.4 mm Hg for IOPcc (85%, 85%) and the area under the curve was greater for IOPcc (0.93 vs. 0.78; p < 0.001).
IOPcc may account for measurement error induced by corneal biomechanics. Compared to GAT, IOPcc may be a superior test in the evaluation of glaucoma but is unlikely to represent an effective diagnostic test.
为了更好地了解角膜特性和眼内压（IOP）在原发性开角型青光眼（POAG）评估中的作用；并确定使用未经角膜生物力学校正和校正的 IOP 来识别青光眼视神经病变（GON）的可行性。
回顾了连续评估的 1875 只新患者的记录。如果中央角膜厚度（CCT）或眼反应分析仪（ORA）测量值不可用，则排除这些眼睛。根据临床检查、眼底照相和海德堡视网膜断层扫描时视盘、边缘和视网膜神经纤维层的形态，确定 GON 的存在或不存在。记录未经治疗状态下的 Goldmann 压平眼压（GAT），并使用 ORA 获得 Goldmann 相关眼压（IOPg）和角膜补偿眼压（IOPcc）。使用 21mmHg 的常规截定点将青光眼眼分类为正常或高眼压（NTG、HTG）。从每位患者中随机选择一只合格的眼睛进行纳入。
共纳入 357 只正常眼、155 只 HTG 眼和 102 只 NTG 眼。在 NTG 眼中，IOPcc 大于 GAT（19.8 和 14.4mmHg；p<0.001），并且在这个 NTG 亚组患者中，IOPcc 与 GAT 之间的差异最大（p≤0.01）。用于检测 GON 的最大综合敏感性和特异性发生在 GAT 为 20.9mmHg（59%，90%）和 IOPcc 为 18.4mmHg（85%，85%），并且 IOPcc 的曲线下面积更大（0.93 对 0.78；p<0.001）。
IOPcc 可能解释了角膜生物力学引起的测量误差。与 GAT 相比，IOPcc 可能是评估青光眼的更好测试，但不太可能代表有效的诊断测试。
