In keratoconus patients, stage-dependent differences in corneal healing capacity exist: Stage I (>500 μm) demonstrates preserved stromal reserves, organized epithelium, and normal tear film [37,38] while Stage II (400–500 μm) shows epithelial instability (microcysts, reduced hemidesmosomes), higher risk of deeper stromal damage during UV application, tear film dysfunction (lower TBUT), and amplified inflammatory response (elevated IL-6/TNF-α, increased keratocyte apoptosis and metalloproteinase (MMP-9) activation) [39,40,41] with slower healing rates, particularly below 400 μm [42]. This evidence concerns the gene MMP9 and keratoconus.