I. Bucherer syndrome type I aliases: ① corneal granular dystrophy syndrome; ② corneal granular dystrophy; ③ corneal nodular degeneration; ④ familial hereditary corneal dystrophy (nodular type); ⑤ familial small nodular corneal degeneration; ⑥ Groenouw’s granular corneal dystrophy syndrome type I; ⑦ Groenouw’s syndrome type I. Summary: Groenouw first reported it in 1890, and then he made detailed pathological histological observations, mostly within 10 years of age with symmetrical onset in both eyes, gradually becoming obvious in adolescence, with the main feature of corneal patchy clouding. Third, the etiology of the pathology: the etiology is unclear, autosomal dominant inheritance. The pathology shows the accumulation of glassy material between the corneal epithelium and the anterior elastic layer, the splitting of the anterior elastic layer, and the breakage of nerve fibers. Ocular features: gray-white patchy or granular irregular clouding in the central parenchymal layer of both eyes, varying in size, with clear borders, sometimes causing some degree of visual impairment, but not invading the parenchymal layer, and the cornea between the spots is transparent. Corneal perception is normal or slightly diminished, there may be intermittent corneal irritation symptoms. V. Systemic features: no special manifestations. Sixth, treatment: no special treatment, low vision to consider corneal transplantation. The cloudy cornea removed during surgery can be pathologically examined.