The central cornea in this condition may be thinned. Significant cornea guttata may be present. The gene responsible for macular dystrophy is located on chromosome 6. The metabolic defect for this condition appears to be an error in the synthesis of keratan sulfate. Two different types of macular dystrophy exist based on the absence or presence of keratan sulfate within the corneal stroma.
Light microscopy reveals glycosaminoglycan deposits within stromal keratocytes.
Deposits in macular dystrophy are composed of glycosaminoglycans, which stain with Alcian blue and colloidal iron. Light microscopy demonstrates glycosaminoglycan deposits within stromal keratocytes. Two different types of macular dystrophy are based on the absence or presence of keratan sulfate within the corneal stroma. Sunglasses are often helpful for severe glare symptoms. PTK works best when the opacities are superficial.