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Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
[Evaluation of the self-tonometer Icare ONE in comparison to Goldmann applanation tonometry]
1Universitätsaugenklinik Rostock, Doberanerstr. 140, 18057 Rostock. verenawitte@googlemail.com
Objective:
The aim of this clinical study was to demonstrate the practicability of self-measured intraocular pressure and to evaluate the reliability by comparing the data with those obtained by Goldmann applanation tonometry (GAT).
Methods:
A total of 40 patients aged between 44 and 82 years with glaucoma were introduced to the handling of the tonometer. The self-measurements were done for 1-3 days following the medical measurement by GAT. The data were saved as "correct" or in the case of wrong handling as "false". The impressions of the patients were obtained by a questionnaire.
Results:
A total number of 191 single measurements were registered by the Icare ONE and of these there were 97 (50.8%) signed "false". Of the patients 45% reached a maximum difference of ±5 mmHg between GAT and self-measurement in every single measurement. In the subgroup of under 60-year-old patients 70% reached this result. There were no indications of a systematic error. Of the probands 60% considered the handling of the Icare ONE as difficult. Nevertheless, 80% could imagine using the self-tonometer at home.
Conclusions:
The differences between the self-measurements and the GAT were highly fluctuating in some cases. In the group of patients younger than 60 years the agreement was better, so problems with the handling of the Icare ONE may be an important factor. However, the acceptance in the patients tested was high and continuous pressure measurements at home could be reasonable. Advancements in the handling and reliability are needed to improve clinical application of the measured values.
