Intereye Asymmetry as a Predictor of Progression in Patients With Untreated Keratoconus: Findings From a Longitudinal Study

Arnalich-Montiel, Francisco PhD*,†; Ortiz-Toquero, Sara PhD*; Kandel, Himal PhD‡,§; Lewis, Noni MD‡,¶; Chiong Hong, Sheng MD‖; Downie, Nicholas MD**; Watson, Adam MBChB††; Abbondanza, Marco MD‡‡; Watson, Stephanie PhD‡,§

Author Information
*Department of Ophthalmology, Cornea Unit, Ramón y Cajal University Hospital, Madrid, Spain;
†School of Medicine, University CEU San Pablo, Madrid, Spain;
‡Faculty of Medicine and Health, Save Sight Institute, The University of Sydney, Sydney, New South Wales, Australia;
§Sydney Eye Hospital, Sydney, New South Wales, Australia;
¶Central Sydney Eye Surgeons, Sydney, New South Wales, Australia;
‖Dunedin Public Hospital, Te Ora Whatu Southern, Dunedin, New Zealand;
**Launceston Eye Doctors, Launceston, Tasmania, Australia;
††Eye Institute, Auckland, New Zealand; and
‡‡Abbondanza Eye Centres, Rome and Milan, Italy.

Correspondence: Francisco Arnalich-Montiel, PhD, Department of Ophthalmology, Ramón y Cajal University Hospital, Carretera de Colmenar Viejo Km 9,100, 28034 Madrid, Spain (e-mail: farnalich@gmail.com).

The Save Sight Keratoconus Registry was provided by Keratoconus Australia, and The Australian Vision Research (formerly known as Ophthalmic Research Institute of Australia, ORIA). Grant numbers: not applicable.

The author declares that there is no conflict of interest.
Cornea ():10.1097/ICO.0000000000003601, June 25, 2024. | DOI: 10.1097/ICO.0000000000003601

Purpose:
The purpose of this study was to evaluate interocular predictors of progression in patients with untreated keratoconus.

Methods:
This is a multicenter longitudinal observational study with real-world data collected through the Save Sight Keratoconus Registry. Patients between the period of June 2000 and September 2022 were included in this study. Parameters such as patient age, sex, ocular history, visual acuity, K2, Max-K, and thinnest corneal thickness pachymetry (TCT) were analyzed.

Results:
There were 4342 untreated eyes from 2171 patients with keratoconus. A total of 333 patients showed progression of either Max-K, TCT, or both, whereas 1838 patients showed stable parameters. Factors associated with a higher incidence of progression in Max-K were younger baseline age (HR 0.96 per year older; 95% CI 0.95–0.98, P < 0.0001) and a higher baseline intereye asymmetry in Max-K (HR 1.02 per higher diopter; 95% CI 1.00–1.04, P = 0.04). A younger baseline age was the only predictor of progression in TCT (HR 0.97 per year older; 95% CI 0.95–0.99, P = 0.001). Conclusions:
Age is the most significant predictor of progression for both corneal thinning and progression of Max-K. Interocular asymmetry in Max-K at baseline could be used as part of an algorithm for determining the risk of keratoconus progression. It is recommended that patients with higher interocular asymmetry in Max-K have a closer follow-up of both eyes as they are at a higher risk of progression.

Origin of the article you can find here