Online Photo Diagnosis

By Gregory W. DeNaeyer, OD, FAAO

This photograph shows the left eye of a 78-year-old female patient who has central crystalline dystrophy. Her eye underwent two previous phototherapeutic keratoplasty (PTK) treatments in 1990 and 2005, and her current best corrected visual acuity is 20/40. The patient's right eye had significantly worse dystrophy; however, her best corrected visually acuity improved to 20/30 after a penetrating keratoplasty in 2005.

Central crystalline dystrophy or Schnyder's Dystrophy is a rare autosomal dominant corneal dystrophy that develops by the second or third decade of life^1-5. It is characterized by a central, ring-shaped corneal opacity resulting from polychromatic crystal formation that is confined to the anterior stroma and Bowman's layer^1,6-8. By middle age, significant corneal arcus develops. Be sure to test patients who have this condition for hyperlipidemia, which has been linked to central crystalline dystrophy^1,9-12.

For mild-to-moderate cases, patients may benefit visually from PTK. For more severe presentations, a lamellar graft or penetrating keratoplasty may be required to improve visual acuity, although recurrence is possible^4,13.

References

1. Kaufman, HE. Barron, BA. McDonald, MB. The Cornea 2nd Edition. 1998 Butterworth-Heinemann 437-440.
2. Schnyder, WF. Mitteilung uber einen neuen Typus von familiarer Hornhauterkrankung. 1929 Schweiz Med Wochenschr 59:559.
3. Schnyder, WF: Scheibenformige Kristalleinlagerungen in der Hornhautmitte als Erbleiden. 1939 Klin Monatsbl Augenheilkd 103:494.
4. Delleman JW. Winkelman, JE. Degeneratio corneae cristallinea hereditaria: a clinical, genetical, and histological study. 1968 Ophthalmologica 155:409.
5. Weiss, JS. Schnyder's dystrophy of the cornea: a Swede-Finn Connection. 1992 Cornea 11:93.
6. Karseras, A. Price, A. Central crystalline corneal dystrophy. 1970 Br J Ophthalmol 54:659.
7. Ehlers, N. Mattheissen, M. Hereditary crystalline corneal dystrophy. 1973 Acta Ophthalmol (Copenh) 51:316.
8. Grop K. Clinical and histological findings in crystalline corneal dystrophy. 1973 Acta Ophthalmol (Copenh) 120:52.
9. Luxenberg, M. Hereditary crystalline dystrophy of the cornea. 1967 Am J Ophthalmol 63:507.
10. Bron, AJ. Williams, HP. Carruthers, ME. Hereditary crystalline stromal dystrophy of Schnyder. 1972 I. Clinical features of a family with hyperlipoproteinaemia. Br J Ophthalmol 56:383.
11. Kaden, R. Feurle, G. Schnydersche Hornhautdystrophie und Hyperlipidamie. 1976 Albrecht von Graefes Arch Klin Exp Ophthalmol 198:129.
12. Lisch, W. Weidle, EG. Lisch, C. et al. Schnyder's dystrophy: progression and metabolism. 1986 Ophthalmic Paediatr Genet 7:45.
13. Garner, A. Tripathi, RC. Hereditary crystalline stromal dystrophy of Schnyder. 1972 II. Histopathology and ultrastructure. Br J Ophthalmol 56:400.