Accuracy of intraocular pressure measurements between non-contact tonometer and ICare rebound tonometer / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To analyze the accuracy of non-contact tonometer(NCT)and ICare rebound tonometer(RBT)in measuring intraocular pressure in glaucoma patients. <p>METHODS:A retrospective proportional control study. Totally 113 patients(185 eyes)with glaucoma were studied. Intraocular pressure was measured by RBT, NCT and Goldmann Applanation tonometer(GAT)at 9:00 and 16:00 and recorded as two sets of data, respectively. Their accuracy is evaluated by the rank sum test, and the international standard 8621 guide, Bland-Altman consistency analysis analyzed the consistency of the two groups of measurements, and the data were divided into two groups: abnormal intraocular pressure group(<10mmHg or >21mmHg)and normal intraocular pressure group(10-21mmHg). The consistency was analyzed between different groups. The spearman correlation analysis is adopted to analyze the correlation between ophthalmotonometers.<p>RESULTS: There were differences among the GAT, NCT and RBT measurements(<i>P</i><0.01). There was a strong correlation between the intraocular pressure measured value obtained by GAT and measured values obtained by RBT and NCT(<i>rs</i>=0.71, 0.77, <i>P</i><0.001). The measured values of NCT and GAT are close to each other without statistically significant differences(<i>P</i>=0.92). Compared with GAT, RBT has a higher intraocular pressure measured value, and there are significant differences(<i>P</i><0.05). However, compared with GAT, both NCT and RBT have a wide range of limits of agreement, and they are(-6.2-6.0mmHg)and(-5.2-7.6mmHg)respectively. In normal intraocular pressure groups, the ranges of limits of agreement are(-5.9-5.9mmHg)and(-4.3-7.5mmHg)respectively. In abnormal intraocular pressure groups, the ranges of limits of agreement are(-7.3-6.4mmHg)and(-7.5-5.6mmHg)respectively. The evaluation carried out in accordance with ISO 8612 guides indicates that the abnormal values more than the 95% of consistency restriction of NCT and RBT in the three groups are(3.9%, 11.3%, 12.2%)and(26.3%, 11.3%, 12.2%)respectively.<p>CONCLUSION: Both NCT and RBT cannot simply replace the GAT to measure the intraocular pressure of glaucoma patients. In glaucoma patients, with the deviation of the measured value from the normal intraocular pressure range, the measurement error of NCT and RBT also increase.

Comparison of Icare Rebound Tonometer with Goldmann Applanation Tonometry

PURPOSE: To compare Icare rebound tonometer (IRT) and Goldmann applanation tonometer (GAT) and investigate the clinical usefulness of IRT. METHODS: In a retrospective study of 131 eyes with glaucoma and glaucoma suspect, intraocular pressure (IOP) was measured with IRT and GAT. The correlation between IRT and GAT and the influence of refractive error (spherical equivalent; SE) and central corneal thickness (CCT) were analyzed. RESULTS: A distinct correlation between IRT and GAT was found. IOP measured with GAT was 2.23 +/- 3.16 mm Hg higher than with IRT (p or = -5 diopter) was measured relatively lower than in hyperopic eyes (SE < -5 diopter) with GAT (+1.50 +/- 0.68 mm Hg) and IRT (+1.88 +/- 0.75 mm Hg). CONCLUSIONS: IRT showed strong correlation with GAT, but IOP measured approximately 2 mm Hg lower. The IOP tends to measure lower at low CCT and in myopic eyes.

Comparison of intraocular pressure measured by Icare rebound tonometer and Goldmann applanation tonometer / 中华实验眼科杂志

Background As a new tonometer,it is necessary to assess the clinical value of Icare rebound tonometer.Objective This study was to compare the intraocular pressure(IOP)values measured by Icare with that measured by GAT,and discuss the clinical value of leare rebound tonometer. Methods IOP measurement was performed on 152 eyes of 78 subjects with suspicious glaucoma,glaucoma,refractive error and normal examinnee by Icare and GAT respectively.The Icare IOP was measured firstly and then the GAT IOP was carried out with the 3-or 5-minute interval.The IOP values were compared between Ieare and GAT.This study was approved by Ethic Committee of Wuhan General Hospital of Chinese PLA.Written informed consent was obtained from each subject prior to this study. Results The mean IOP values of Icare and GAT were(19.16±5.03)mmHg and(18.41±4.52)mmHg respectively.The differences between Icare IOP and CAT IOP were less than or equal to 1 mmHg in 96 of 105 eyes(63.2%).The positive correlation was found between the Icare IOP and GAT IOP(r=0.940,P<0.01).The Ieare IOP was lower than that of GAT when IOPIcare<16 mmHg,however,the IOP of Icare were higher when IOPIcare≥6 mmHg;the IOP of Icare were higher than that of GAT in the total CCT range.The correlation coefficients of IOP of Icare or CAT with CCT were 0.341(P<0.01)and 0.333(P<0.01),respectively. Conclusion Compared with GAT,Icare is more feasible in clinic because it is practicable and reliable.

Reproducibility and tolerability of iCare rebound tonometer and its agreement evaluation with Goldmann applanation tonometry / 中华实验眼科杂志

Background Goldmann applanation tonometry (GAT) is a gold standard of intraocular pressure measurement.But its utilization iS limited because of its complexity and high requirement of cooperation.iCare rebound tonometer (iCare RBT) is a new type of applanation tonometry,and its accuracy and safety in clinical application need to be evaluated.Objective Present study was to investigate the reproducibility and tolerability of iCare RBT and its measurement agreement with GAT over a wide intraocular pressure (IOP) range. Methods The IOP were measured in bilateral eyes of 36 glaucoma and glaucoma suspect patients by 2 examinees with iCare RBT at the 1-minute interval to assess the interobserver reproducibility.Then the IOP of both eyes from 56 Subjeets and other 52 subjects were separately measured twice for each by two operators with iCare RBT for the evaluation of intraobserver reproducibility.Finally.IOP of 182 eyes of 92 glaucoma and glaucoma suspect patients was obtained by examiner 2 with RBT first and examiner 1 with GAT subsequently at a 2.minute interval in a masked fashion to perform an agreement evaluation of two readings by using Bland-Ahman method.The tolerance of subjects to iCare RBT measurement were surveyed.Oral informed consent was obtained prior to the IOP measurement. Results Concerning the iCare RBT readings.interobserver correlation coefficients were 0.937 in the right eye and 0.887 in the left eye.Intraobserver correlation coefficients of examiner 1 were 0.986 in the left eyes and 0.969 in the fight eyes.And those of examiner 2 were 0.990 and 0.979.Mcan values of iCare RBT readings and GAT were(18.74±8.36)mmHg and(19.33±8.20)mmHg and the mean difference values(iCare-GAT)was(-0.59 4±2.60)mmHg with the 95%confidence interval of -5.80-4.60 mmHg.The correlation coefficient between two modalities of IOP measurement WaS 0.95 1.No severe pain and discomfort were complained in all the subjects during or after measurement of iCare RBT. Conclusion iCare RBT has good interobserver and intraobserver reproducibility and good tolerance.It was proved that this is a good correlation between iCare RBT readings and GAT readings.