Granular dystrophy is a relatively common autosomal dominant condition that is characterized by deposition of hyaline. The hyaline within the stromal tissue stains with Masson Trichrome.
Granular dystrophy manifests during the first decade of life as sharply demarcated, milky, opaque lesions resembling snowflakes or bread crumbs. The lesions are located in the axial portion of the superficial stroma. Between the dense opacities, the intervening cornea is characteristic clear.
Granular Dystrophy Before Treatment
Granular dystrophy does not require keratoplasty as often as the other familial dystrophies because visual acuity may be good if the clear spaces align with the visual axis. Some patients get a beneficial pinhole effect based on the pattern of lesions.
Recurrent erosions may occur when the basement membrane is involved, but this happens less frequently than in lattice dystrophy. If the lesions coalesce and occlude the visual axis, phototherapeutic keratectomy (PTK) or penetrating keratoplasty may be necessary.
Granular Dystrophy After Phototherapeutic Keratectomy
PTK uses the excimer laser to treat corneal surface diseases and scars. PTK is performed by removing the epithelium (or outer skin of the cornea) and then applying the laser to the surface of the cornea. The goal is to produce a smoother and clearer cornea, and not necessarily to reduce dependency upon eyeglasses or contact lenses.
PTK is for those of any age who have corneal surface diseases such as:
• Recurrent epithelial erosion syndrome.
• Shallow corneal scars.
• Corneal dystrophies, such as lattice dystrophy or granular dystrophy.