Tehran University of Medical Sciences

Science Communicator Platform

Stay connected! Follow us on X network (Twitter):
Share this content! By
Assessment of Tonometry Methods in Keratoconic Eyes Following Intracorneal Ring Segments Implantation: A Comparative Study Publisher



S Zarei Ghanavati SIAMAK ; Sm Tabatabaei Seyed MEHDI ; S Gholamhoseinpouromran SAMANEH ; H Hosseinikhahmanshadi HAMED ; S Banan SAEED ; M Aminizade MEHDI ; K Esmaili KOSAR ; E Azaripour EBRAHIM
Authors

Source: Korean Journal of Ophthalmology Published:2025


Abstract

Purpose: To compare intraocular pressure (IOP) readings from corneas with intracorneal corneal ring segments (ICRS) using various methods, including Goldmann applanation tonometry (GAT), Tonopen, corneal-compensated IOP from the Ocular Response Analyzer (ORA), and biomechanically corrected IOP from the Corneal Visualization Scheimpflug Technology (Corvis ST). Methods: This cross-sectional observational study included participants who had undergone ICRS implantation with KeraRing at least 3 months before the study. The mean IOP recorded by different instruments was compared using analysis of variance. Agreement among the methods was assessed with Bland-Altman plots. Results: A total of 54 eyes from 27 participants were enrolled. The mean IOP measured by Tonopen was significantly lower in the center compared to the peripheral quadrants (p < 0.001). IOP measured by GAT was significantly lower than that measured by Tonopen (13.02 ± 2.31 mmHg vs. 14.50 ± 2.91 mmHg, p = 0.021). There were no significant differences between the IOP measurements provided by Tonopen, ORA, and Corvis ST. The corneal-compensated IOP from ORA and biomechanically corrected IOP from Corvis ST had the highest correlation, with a weak intraclass correlation coefficient of 0.38. Conclusions: IOP measurements using Tonopen were significantly lower in the central 5-mm zone compared to other quadrants. GAT measurements were significantly lower than those from Tonopen. Different measurement tools did not show a strong correlation. Corvis ST (biomechanically corrected IOP) tended to present lower readings at higher IOP levels in eyes with ICRS. © 2025 Elsevier B.V., All rights reserved.
Related Docs
View other Related Docs
1. Intrastromal Corneal Ring Segment Implantation (Keraring 355°) in Patients With Central Keratoconus: 6-Month Follow-Up, Journal of Ophthalmology (2015)
2. Visual and Refractive Outcomes and Tomographic Changes After Femtosecond Laser-Assisted Intrastromal Corneal Ring Segment Implantation in Patients With Keratoconus, Journal of Ophthalmic and Vision Research (2018)
3. Complete 360-Degree Intrastromal Corneal Rings With and Without Corneal Cross-Linking in the Management of Keratoconus, Keratoconus: Optical and Surgical Management (2024)
Experts (# of related papers)
View all Related Experts
Masomeh Mohebbi (3)
Akbar Fotouhi (3)
Other Related Docs
4. Additional Intrastromal Corneal Ring Segments in Keratoconus, Cornea (2018)
5. The Association of Central Corneal Thickness With Ocular and General Parameters in a Community Setting: The Yazd Eye Study, Journal of Ophthalmic and Vision Research (2017)
6. Tonometry by Ocular Response Analyzer in Keratoconic and Warpage Eyes in Comparison With Normal Eyes, Journal of Current Ophthalmology (2021)
7. Myoring Implantation With and Without Corneal Collagen Crosslinking for the Management of Keratoconus, Journal of Ophthalmic and Vision Research (2020)
8. Mini-Scleral Contact Lens for Management of Poor Visual Outcomes After Intrastromal Corneal Ring Segments Implantation in Keratoconus, Journal of Ophthalmic and Vision Research (2016)
9. Corneal Profile in Primary Congenital Glaucoma, Acta Ophthalmologica (2017)
10. Evaluation of Corneal Biomechanical Properties in Patients With Thyroid Eye Disease Using Ocular Response Analyzer, Journal of Glaucoma (2016)
11. Comparison of the Myoring Implantation Depth by Mechanical Dissection Using Pocketmaker Microkeratome Versus Melles Hook Via As-Oct, BMC Ophthalmology (2018)
12. Angle Kappa Measurements: Normal Values in Healthy Iranian Population Obtained With the Orbscan Ii, Iranian Red Crescent Medical Journal (2015)
13. Keratoconus Clinical Findings According to Different Classifications, Cornea (2015)
14. Standard and Accelerated Corneal Cross-Linking Long-Term Results: A Randomized Clinical Trial, European Journal of Ophthalmology (2020)
15. Biomechanical Changes in Keratoconus After Customized Stromal Augmentation, Taiwan Journal of Ophthalmology (2024)
16. Corneal Scheimpflug Densitometry in Photorefractive Keratectomy Candidates, Cornea (2020)
17. Intraocular Pressure Trend Following Myopic Photorefractive Keratectomy, International Ophthalmology (2022)
18. Longitudinal Changes in the Intraocular Pressure and Their Related Factors Among Adults Aged 40 to 64 Years, Scientific Reports (2025)
19. Anterior Segment Parameters As Predictors of Intraocular Pressure Reduction After Phacoemulsification in Eyes With Open-Angle Glaucoma, Journal of Cataract and Refractive Surgery (2017)
20. Five Year Changes in Central and Peripheral Corneal Thickness: The Shahroud Eye Cohort Study, Contact Lens and Anterior Eye (2016)