Clinical Evaluation of the New Rebound Tonometers Icare PRO and Icare ONE Compared with the Goldmann Tonometer

Abstract

Purpose: To compare the participant-obtained intraocular pressures (IOPs) using Icare ONE and the clinician-obtained values using Icare PRO, both rebound tonometers, with Goldmann tonometry (GAT) values and analyze the ease of use of Icare ONE. Methods: One hundred fifty participants were included (60 normal controls, 90 patients with glaucoma/ocular hypertension). The participants measured the IOP 3 times using Icare ONE; a clinician measured the IOP once using Icare PRO. The instruments were used randomly. Clinical data were evaluated to analyze the difficulty of the technique, the effect on the results, and the ease of use of Icare ONE. Results: The mean IOPs with GAT, Icare ONE, and Icare PRO were 16.6±4.43, 17.5±5.42, and 16.6±4.77 mm Hg, respectively. The participant-measured IOP values were within +3 mm Hg of the GAT values in 67.1% of eyes with Icare ONE and in 79.6% with Icare PRO. The limits of agreement were higher with Icare ONE compared with Icare PRO. IOP value errors were found with Icare ONE in eyes with low and high GAT-IOP. The areas under the curve to detect IOPs of 21 mm Hg or higher (GAT) exceeded 0.80 with both tonometers. Young participants reported better ease of use with Icare ONE. No other factors were related to the results. Conclusions: Icare ONE may be useful for patients monitoring their IOP values; most individuals can use the device after a short training session. Icare PRO had better results compared with Icare ONE in all IOP ranges.