Evaluation of rebound tonometer iCare IC200 as compared with IcarePRO and Goldmann applanation tonometer in patients with glaucoma

Abstract

Background This study investigated the agreement between a new rebound tonometer, IC200, and IcarePRO and Goldmann applanation tonometry (GAT). Methods This was a prospective cross-sectional study. We measured the intraocular pressure (IOP) in 145 eyes of 145 glaucoma patients in the sitting position using GAT, IcarePRO, and IC200. IcarePRO and IC200 measurements were also obtained in the supine position. IC200 measurement was performed using two modes: single six (IC200-single) and automatic (IC200-continuous) six-measurements mode. Results All tonometers provided high reproducibility in both positions (all intraclass correlation coefficients > 0.90), although it was highest with GAT, followed by IC200-continuous and IC200-single and then IcarePRO. In the sitting position, the mean (± SD) IOPs of GAT, IcarePRO, IC200-single, and IC200-continuous were 14.5 ± 2.9 mmHg, 13.3 ± 3.2 mmHg, 11.6 ± 3.2 mmHg, and 11.5 ± 3.2 mmHg, respectively. IOPs measured with IcarePRO or IC200 were significantly lower than those with GAT, particularly in patients with low IOP. IOPs measured with all tonometers were significantly elevated in the supine position as compared with the sitting position, but this difference was significantly greater with IC200-single and IC200-continuous compared with IcarePRO. IOP elevation was significant in eyes without bleb versus those with bleb, but this finding was not observed when IOP was measured with IcarePRO. The IOPs of the single and continuous modes of IC200 were interchangeable in both positions. Conclusions GAT, IcarePRO, and IC200 had sufficiently high reproducibility, but measurements with IcarePRO may not be accurate in the supine position. Elevation of IOP in the supine position, especially in eyes with bleb, was more sensitively captured with IC200 than with IcarePRO. Trial registration Japan Clinical Trials Register, No. UMIN000039982.

Difference in Intraocular Pressure between Sitting Versus Supine Positions in Healthy and Glaucomatous Children by Rebound tonometery

“…Moreover, these IOP changes have been associated with an increase in nocturnal IOP and could be related to the progression of glaucoma. 20 In contrast to our results, Nakakura et al 21 , conducted a recent prospective cross-sectional study They used GAT, IcarePRO, and IC200 on 145 eyes of 145 glaucoma patients in the sitting and supine positions, and found no significant variations in IOP values between the sitting (13.3 mmHg) and supine positions (14.5 mmHg) for Icare PRO rebound tonometer, with difference (1.2 mmHg). Uzlu et al 22 , conducted a study on 49 eyes of 49 healthy children.…”

A Comparison of Intraocular Pressure Measurement using SUOER SW-500 Rebound Tonometer and Conventional Reusable Goldmann Prisms

“…Previous studies showed that the mean IOP difference between Icare PRO and GAT was between -0.38mmHg to 0.43mmHg [17][18]. As for the newest model of Icare the IC200, the mean IOP was approximately 3 mmHg lower than that of GAT IOP in a recent study by Nakamura et al [19].…”

Posture-Induced Intraocular Pressure Changes after iStent Inject W Combined with Phacoemulsification in Open Angle Glaucoma Patients

“…ICare IOP values were lower by 3.1–4.0 mmHg than GAT values throughout follow-up points in our study. Several previous reports showed that ICare IOP values were lower by 0.4–3.0 mmHg than GAT values [ 29 , 30 , 31 , 32 ]. Our result is largely consistent with those previous reports.…”