Comparison of intraocular pressure measurements between Icare PRO Tonometer, Goldmann Applanation Tonometer and non-contact tonometer in healthy and glaucomatous eyes

Abstract Purpose: To validate the comparative measurements of intraocular pressure performed with IcarePRO tonometer (IPT) in relation to Goldmann applanation tonometer (GAT) and non-contact tonometer (NCT), as well as to evaluate the influence of central corneal thickness (CCT) on these values. Methods: This was a prospective and comparative study conducted during 6 months in the Department of Ophthalmology, Hospital de Braga, Portugal. The study population comprised two groups: healthy adults and adults with primary open angle glaucoma (POAG). The IOP values were obtained by the three tonometers and the order of execution was randomly selected. CCT values were obtained by ultrasonic pachymetry. Results: A total of 168 eyes (74 with diagnosis of POAG and 94 healthy) of 84 patients were included in this study. The mean IOP values obtained by IPT, GAT and NCT were 17.36±3.78 mmHg; 14.59±3.32 mmHg; and 17.04±4.01 mmHg, respectively. The comparison between IPT and NCT did not reveal statistically significant differences in the two groups studied. However, statistically significant differences were obtained between IPT and GAT values (p &lt;0.001). The IOP values, recorded by all the tonometers, were significantly and positivily correlated with the CCT (p &lt;0.001). Conclusion: IOP readings measured by IPT are comparable with those obtained by NCT, but higher than those obtained by the GAT. CCT values are correlated with IOP measurements with IPT, as it does in GAT and NCT, and should be always taken into consideration.摘要 研究目的：验证IcarePRO眼压计（IcarePRO tonometer，IPT）与戈德曼压平眼压计（Goldmann applanation tonometer，GAT）、非接触式眼压计（non-contact tonometer，NCT）所测得的眼内压（intraocular pressure，IOP）的可比性，并评估中央角膜厚度（central corneal thickness，CCT）对上述测量值的影响。 研究方法：本研究为前瞻性对照研究，于葡萄牙布拉加医院眼科开展，研究周期为6个月。研究对象分为两组：健康成年人与原发性开角型青光眼（primary open angle glaucoma，POAG）患者。所有受试者的眼内压均通过三台眼压计测量，测量顺序随机选取；中央角膜厚度采用超声角膜测厚法获取。 研究结果：本研究共纳入84例患者的168只眼，其中74只眼确诊为原发性开角型青光眼，94只眼为健康眼。IcarePRO眼压计、戈德曼压平眼压计与非接触式眼压计测得的平均眼内压分别为17.36±3.78 mmHg、14.59±3.32 mmHg及17.04±4.01 mmHg。两组受试者中，IcarePRO眼压计与非接触式眼压计的测量结果均无统计学显著差异；但IcarePRO眼压计与戈德曼压平眼压计的测量值存在显著统计学差异（p<0.001）。三台眼压计所测得的眼内压均与中央角膜厚度呈显著正相关（p<0.001）。 研究结论：IcarePRO眼压计测得的眼内压与非接触式眼压计结果具有可比性，但高于戈德曼压平眼压计的测量值。中央角膜厚度与IcarePRO眼压计、戈德曼压平眼压计及非接触式眼压计的眼内压测量值均存在相关性，临床实践中应始终将其纳入考量。