Bietti’s Crystalline Dystrophy

Eye Parts with LabelsWhat is Bietti’s crystalline dystrophy?

Bietti’s crystalline dystrophy (BCD) is a rare inherited eye disease that causes crystals in the cornea (the clear covering of the eye) and atrophy (shrinkage) of the back layers of the eye. It is named after Dr. G.B. Bietti, an Italian ophthalmologist who first described the condition in the 1930s. BCD tends to be more common in people of Asian descent.

What causes Bietti’s crystalline dystrophy?

BCD is known as an autosomal recessive trait. That means that you need two copies of the BCD gene—one from your mother and one from your father—to develop the disease. Researchers have identified the gene that causes BCD, called CYP4V2, which is located on chromosome number 4. Scientists believe this gene is involved in the production of fatty acids and steroids.

What are the signs and symptoms of Bietti’s crystalline dystrophy?

If you have BCD, a vision exam may show that you have:

  • Crystals on your corneas
  • Yellow, shiny deposits on your retinas
  • Progressive atrophy of the retina, choriocapillaries, and choroid at the backs of your eyes

Lab tests may also indicate that you have crystals in some of your white blood cells.

BCD crystals do not appear to cause harm, but you may notice vision problems such as:

  • Night blindness
  • Impairment of your visual field

Can BCD be treated?

There is no cure or treatment for BCD. Scientists hope to apply the findings of genetic research to developing an effective therapy.