Thelansis

  Fuchs endothelial dystrophy (FED) is a primary disorder affecting the corneal endothelium, characterized by progressive corneal edema and subsequent vision impairment. Typically manifesting between the fifth and seventh decades of life, its hallmark features include the gradual accumulation of focal excrescences known as "guttae" and thickening of Descemet's membrane, a collagen-rich layer secreted by endothelial cells. As endothelial cell density diminishes, the cornea's ability to maintain transparency declines, leading to significant visual impairment due to corneal edema. While corneal guttae indicate FED, the development of stromal edema is diagnostic. Symptoms include morning visual blurring and edema of the stroma and epithelium, resulting from decreased tear film osmolality. Mutations in collagen VIII, a crucial constituent of Descemet's membrane, have been implicated in FED pathogenesis. FED progresses through four stages, starting with guttae formati...