Comparison of ICare and IOPen Goldmann applanation tonometry according to international standards 8612 in glaucoma patients.

AIM

To compare IOPen and ICare rebound tonometry to Goldmann applanation tonometry (GAT) according to International Standards Organization (ISO) 8612 criteria.

METHODS

Totally 191 eyes (=107 individuals) were included. Criteria of ISO 8612 were fulfilled: 3 clusters of IOP, measured by GAT, were formed. The GAT results were given as mean±standard deviation.

RESULTS

GAT (19.7±0.5 mm Hg) showed a significant correlation to ICare (19.8±0.5 mm Hg) (=0.547, <0.001) and IOPen (19.5±0.5 mm Hg) (=0.526, <0.001). According to ISO 8612 criteria in all 3 IOP groups the number of outliers (of the 95% limits of agreement) exceeded 5% for ICare and IOPen GAT: No.1 (=68) 29.4% and 22.1%, No.2 (=62) 35.5% and 37.1%, No.3 (=61) 26.2% and 42.6%, respectively.

CONCLUSION

The strict requirements of the ISO 8612 are not fulfilled in a glaucoma collective by ICare and IOPen at present. As long as the Goldmann tonometry is applicable it should be used first of all for reproducible IOP readings. ICare and IOPen tonometry should be considered as an alternative tool, if application of Goldmann tonometry is not possible.