14 Stromal Corneal Dystrophies

Corneal Dystrophy

Broad term for diseases where corneal transparency is reduced d/t the presence of abnormal material

Macular dystrophy

Condition characterized by abnormal accumulation of glycosaminoglycan deposits in corneal stroma

Macular dystrophy pattern of inheritance

Autosomal recessive

Electron microscopy appearance of macular dystrophy

Accumulation of GAG deposits in stroma (stain w/ colloidal iron & alcian blue stains)

Signs of macular dystrophy

Cornea

• stromal opacifications (gray-white, ill-defined, focal)

• Associated w/ diffuse cloudiness of intervening stroma

• Localized from limbus to limbus (central > superficial, peripheral >deep)

Tx/management of macular dystrophy (surgical intervention)

• generally considered d/t high incidence of visually significant opacifications

• Most common consideration is Phototherapeutic Keratectomy

Schnyder Dystrophy (Schnyder central crystallin dystrophy)

condition characterized by cholesterol deposition in central anterior stroma (autosomal dominant; genetic mutations in UBIAD1 gene of chromosome 1p36)

Schnyder Dystrophy associations

Hypercholesterolemia, hypertriglyceridemia, xanthelasma

Signs of Schnyder Dystrophy

Cornea

• stromal opacifications

  • Yellow-white deposit

  • Ring like pattern

  • Crystalline appearance

  • Localized to anterior stroma

• Full-thickness stromal haze (Centrally & in later stages)

• Prominent Arcus lipoides (white-gray ring at corneal periphery, common association)

Tx/management of Schnyder Dystrophy (surgical considerations)

• exciser PTK

  • Utilized to remove superficial crystals in pts w/ severe glare (most likely later in life)

• Corneal transplantation

  • Utilized if severe corneal opacity

  • Most likely later in life

  • Not as common as exciser PTK

Central Cloudy Dystrophy of Francois (Francois Central Cloudy Dystrophy)

Condition characterized by cloudy, polygonal opacities in central cornea (autosomal dominant)

Signs of Central Cloudy Dystrophy of Francois

Cornea

• stromal opacifications (cloudy, gray)

  • Polygonal/rounded separated by clear zones

  • Localized centrally, posteriorly