ESCRS - POCOR403 - Agreement Of Intraocular Pressure Measurements Obtained With Goldmann Applanation Tonometry, Corvis St, And Icare After Penetrating Keratoplasty.

Agreement Of Intraocular Pressure Measurements Obtained With Goldmann Applanation Tonometry, Corvis St, And Icare After Penetrating Keratoplasty.

Published 2026 - 44th Congress of the ESCRS

Reference: POCOR403 | Type: Free paper | DOI: 10.82333/jaxz-dj21

Authors: A/Prof. Argyrios Tzamalis* 1 , Mrs Tatiana Tziola 1 , Ms Maria Samouilidou 1 , Mr Panagiotis Garitsis 1 , Prof. Nikolaos Ziakas 1

12nd Department of Ophthalmology,Aristotle University of Thessaloniki,Thessaloniki,Greece

Purpose

This study aimed to compare intraocular pressure (IOP) measurements obtained with three different tonometry methods—Goldmann applanation tonometry (GAT), Corvis ST, and iCare—in patients who had undergone penetrating keratoplasty (PK).

Setting

2nd Department of Ophthalmology, Aristotle University of Thessaloniki, Papageorgiou General Hospital, Thessaloniki, Greece

Methods

This observational cross-sectional study prospectively recruited patients with a history of PK. IOP was measured using GAT, iCare, and Corvis ST, including both uncorrected Corvis IOP (CVS-IOP) and biomechanical IOP (bIOP). Agreement between the measurement methods was assessed using Bland–Altman analysis. Secondary analyses evaluated the effects of central corneal thickness (CCT), the number of remaining sutures, corneal donor button size, and the use of topical antiglaucoma medications on IOP readings across the different tonometers.

Results

Twenty-five eyes from 25 patients were included. Bland–Altman analysis demonstrated the narrowest limits of agreement (LoA) between GAT and bIOP (7.5 mmHg). The comparison between iCare and GAT revealed a mean bias of 1.26 ± 3.8 mmHg, with greater variability observed in eyes with a higher number of remaining sutures (p = 0.0079). Increased CCT was moderately associated with lower bIOP values (p = 0.0067); however, CCT did not significantly affect the differences between GAT and the other tonometry methods. No significant differences in IOP measurements were observed in relation to antiglaucoma medication use or corneal donor button size.

Conclusions

Overall, good agreement was observed among iCare, CVS-IOP, bIOP, and GAT measurements, with the closest agreement found between GAT and bIOP. Variability between GAT and iCare measurements appeared to be influenced by the number of sutures at the graft–host junction. Although higher CCT was associated with lower bIOP readings, CCT did not significantly impact the differences between GAT and the alternative tonometry methods.