eCite Digital Repository

Comparison of the Icare ic100 rebound tonometer and the Goldmann Applanation Tonometer in 1,000 Eyes


Subramaniam, AG and Allen, P and Toh, T, Comparison of the Icare ic100 rebound tonometer and the Goldmann Applanation Tonometer in 1,000 Eyes, Ophthalmic Research, 64, (2) pp. 321-326. ISSN 0030-3747 (2021) [Refereed Article]

Copyright Statement

Copyright 2020 S. Karger AG, Basel

DOI: doi:10.1159/000511455


Background: Measurement of intraocular pressure (IOP) forms a crucial component in the diagnosis and management of glaucoma. Many devices have been developed to measure IOP with Goldmann applanation tonometry (GAT) considered the gold standard for IOP measurement.

Objectives: The objective was to compare the IOP measured using Icare ic100 and GAT.

Methods: This cross-sectional study measured IOP in 1,000 eyes (500 left and 500 right) using the Icare ic100 and GAT. Central corneal thickness (CCT) was measured using a hand-held pachymeter. IOP measurements were investigated in all eyes, by IOP substrata, by CCT group, by number of topical glaucoma medications, and diagnosis.

Results: There was moderate agreement between ic100 and GAT IOP measurements (intraclass correlation coefficient 0.73). Mean IOP was significantly lower when measured by ic100 than by GAT (12.1 vs. 16.2 mm Hg, p < 0.0001). Mean ic100 IOPs were also significantly lower than mean GAT IOPs within each IOP strata ≤12 (7.9 vs. 9.7 mm Hg, p < 0.0001), 13-21 (12.1 vs. 16.6 mm Hg, p < 0.0001), and ≥22 (18.4 vs. 25.2 mm Hg, p < 0.0001) and within each subanalysis.

Conclusions: The Icare tonometer consistently under estimated IOP compared to GAT, irrespective of CCT ranges and other subgroup analyses. The mean difference of 4.2 mm Hg can have significant clinical implications, particularly in the management of glaucoma patients.

Item Details

Item Type:Refereed Article
Keywords:Goldmann applanation tonometer, Icare rebound tonometer, intraocular pressure
Research Division:Biomedical and Clinical Sciences
Research Group:Ophthalmology and optometry
Research Field:Ophthalmology
Objective Division:Health
Objective Group:Clinical health
Objective Field:Treatment of human diseases and conditions
UTAS Author:Subramaniam, AG (Mr Arjun Subramaniam)
UTAS Author:Allen, P (Dr Penny Allen)
ID Code:146577
Year Published:2021
Web of Science® Times Cited:3
Deposited By:Rural Clinical School
Deposited On:2021-09-14
Last Modified:2021-11-23

Repository Staff Only: item control page