Study explores corneal layer thickness changes in keratoconus progression
A recent study characterized changes in corneal layer thickness across various stages of keratoconus (KC), providing new insights into disease progression and its underlying mechanisms.
Researchers analyzed data from 164 eyes, including 69 with clinical KC, 32 with topographic KC (no clinical signs), 22 with very asymmetric ectasia with normal topography (VAE-NT), and 41 control eyes. Corneal epithelial, stromal, and total thicknesses were measured using swept-source anterior segment optical coherence tomography (AS-OCT).
Distinct patterns in corneal thickness changes were found. In controls and VAE-NT eyes, the epithelial layer was thicker inferiorly than superiorly. However, while VAE-NT eyes showed stromal thinning in the paracentral inferior and midperipheral temporal areas, their epithelial thickness closely resembled controls.
In contrast, eyes with topographic and clinical KC displayed thinner epithelium, particularly in the inferior-temporal region, accompanied by significant stromal thinning in the central and paracentral areas. These changes were more pronounced as KC severity increased, with the thinnest epithelial points shifting temporally and inferiorly.
The study concluded that stromal changes may precede epithelial alterations in KC progression.
Reference
Koh S, Inoue R, Ambrósio R Jr, et al. Corneal Layer Thickness Mapping With Optical Coherence Tomography in Different Stages Reveals Pathologic Processes of Keratoconus. Cornea. 2024;doi: 10.1097/ICO.0000000000003693. Epub ahead of print. PMID: 39535835.
