Zareei Athar, Razeghinejad Mohammad Reza, Salouti Ramin
Poostchi Ophthalmology Research Center, Department of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran.
Glaucoma Service, Wills Eye Hospital, Philadelphia, PA, United States.
Med Hypothesis Discov Innov Ophthalmol. 2018 Summer;7(2):68-72.
The correct estimation of Intraocular Pressure (IOP) is the most important factor in the management of various types of glaucoma. Primary congenital glaucoma is a type of glaucoma that can cause blindness in the absence of control of the IOP. In this retrospective observational study, 95 eyes, including 48 healthy eyes and 47 eyes with Primary Congenital Glaucomatous (PCG) were studied. Two groups were matched for age, gender, and Goldman Applanation Tonometry (GIOP). Corneal Hysteresis (CH), Corneal Resistance Factor (CRF), and Goldman intraocular pressure were measured by ORA (IOPg), and corneal compensated Intraocular Pressure (IOPcc) was measured for each patient using the Ocular Response Analyzer (ORA). Central Corneal Thickness (CCT) was measured by ultrasonic pachymetry. For each patient, one eye was selected randomly. Student's t-test and analytical regression were used for statistical analysis. The two groups were matched for age (P = 0.34), gender (P = 0.47), and GIOP (P = 0.17). Corneal hysteresis and CRF were significantly lower in PCG than in normal eyes (P < 0.0001), yet CCT was significantly thicker in PCG than normal eyes (P < 0.0001). The regression equation on the effect of CH, CRF, and CCT on GIOP in the PCG group showed that CH and CRF (P-value = 0.001 and P-value<0.0001) also had a significant effect yet CCT did not (P-value = 0.691). A significant decrease in CH and CRF was found in the PCG group compared to the normal controls. In the PCG group, the CCT was greater than normal. These results showed the usefulness of biomechanical properties (CH, CRF) in order to interpret IOP measurements. Furthermore, GIOP measurement may not be confined to consideration of CCT alone. A low CH and CRF value could be responsible for under-estimation of GIOP in the PCG group, in comparison to the normal controls.
正确估计眼内压（IOP）是各类青光眼治疗中最重要的因素。原发性先天性青光眼是一种若不控制眼内压可导致失明的青光眼类型。在这项回顾性观察研究中，对95只眼睛进行了研究，其中包括48只健康眼睛和47只原发性先天性青光眼（PCG）眼睛。两组在年龄、性别和Goldmann压平眼压计测量值（GIOP）方面进行了匹配。通过ORA测量角膜滞后（CH）、角膜阻力因子（CRF）和Goldmann眼内压（IOPg），并使用眼反应分析仪（ORA）为每位患者测量角膜补偿眼内压（IOPcc）。通过超声测厚法测量中央角膜厚度（CCT）。为每位患者随机选择一只眼睛。采用学生t检验和分析回归进行统计分析。两组在年龄（P = 0.34）、性别（P = 0.47）和GIOP（P = 0.17）方面相匹配。PCG组的角膜滞后和CRF显著低于正常眼睛（P < 0.0001），然而PCG组的CCT显著厚于正常眼睛（P < 0.0001）。PCG组中CH、CRF和CCT对GIOP影响的回归方程表明，CH和CRF（P值 = 0.001和P值<0.0001）也有显著影响，而CCT没有（P值 = 0.691）。与正常对照组相比，PCG组的CH和CRF显著降低。在PCG组中，CCT大于正常水平。这些结果表明生物力学特性（CH、CRF）在解释眼压测量方面的有用性。此外，GIOP测量可能不能仅局限于考虑CCT。与正常对照组相比，PCG组中较低的CH和CRF值可能是导致GIOP低估的原因。
