Corneal collagen and associated stromal protein matrix

The corneal collagen and associated stromal protein matrix is the primary structural component of the eye's cornea, accounting for approximately 90% of its total thickness [1]. It is composed of highly organized collagen fibrils, predominantly Type I and Type V, which are arranged in parallel lamellae to provide mechanical strength and maintain corneal shape [1, 3]. These fibrils are precisely spaced by small leucine-rich proteoglycans (SLRPs), such as lumican and keratocan, which are essential for maintaining the optical transparency required for vision [3]. In pathological conditions like keratoconus or post-surgical ectasia, the structural integrity of this matrix is compromised, leading to progressive thinning and visual distortion [2, 4]. This matrix is the direct therapeutic target of corneal collagen cross-linking (CXL), a procedure that uses riboflavin as a photosensitizer under UV-A light to induce new covalent bonds between collagen molecules [2]. This intervention increases the biomechanical stiffness of the stroma, effectively halting the progression of ectatic diseases and preserving visual acuity [2]. (Citations: [1] Meek & Knupp, Prog Retin Eye Res, 2015; [2] Raiskup & Spoerl, Ocul Surf, 2013; [3] Hassell & Birk, Exp Eye Res, 2010; [4] NIH/NEI Keratoconus Overview).

Other names

Corneal stromaCorneal extracellular matrixCorneal collagen fibrilsStromal ECM

Photo-induced oxidative cross-linking of collagen fibers to enhance biomechanical stability