When Fuchs Meets Keratoconus: A Rare Dual Corneal Challenge–Two Case Reports

Introduction

Keratoconus (KC) is a bilateral, progressive, non-inflammatory, asymmetrical ectatic disease characterized by anterior corneal bulging and stromal thinning. Serious complications, such as high levels of astigmatism and corneal scarring, can occur [1].

Fuchs endothelial corneal dystrophy (FECD) is a bilateral, non-inflammatory disease characterized by the loss of corneal endothelial cells and the presence of guttae on Descemetʼs membrane. According to the 2024 update of the International Committee on Classification of Corneal Dystrophies (IC3D), FECD is classified as a primary endothelial corneal dystrophy with genetic heterogeneity [2]. It is the most common cause of corneal transplantation worldwide. The condition that can result in vision loss is a consequence of a multifaceted interplay between genetic and environmental factors [3].

KC and FECD are corneal diseases that are typically studied in isolation. However, some studies have reported the concurrent occurrence of these two diseases in the same eye [4]. This observation has been postulated to have a genetic basis. A study indicated that KC and FECD may share a common genetic basis, and genetic screening and counseling may help identify individuals at increased risk, thereby potentially informing early monitoring or preventive strategies in select cases [5]. Furthermore, studies have indicated that polymorphisms in the LIG3 and RAD51 genes may contribute to the pathogenesis of these diseases, and that these genes can serve as potential markers [6], [7].

This report presents the corneal topography, anterior segment optical coherence tomography (AS-OCT), and in vivo confocal microscopy (IVCM) findings of two patients with KC and FECD.

Publication History

Received: 06 April 2025

Accepted: 18 September 2025

Accepted Manuscript online:
19 September 2025

Article published online:
02 December 2025

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