Corneal Degenerations & Deposits

Corneal Arcus

Bilateral white ring localized to peripheral cornea; very common condition; Argus senilis & Arcus lipoides

Arcus senilis

M. Common; geriatric individuals

Arcus lipoides

Younger individuals; associated w/ hyperlipidemia

Pathogenesis of corneal Arcus

Low density lipoproteins accumulate w/in lumbar capillaries (located at junction of cornea & sclera)

Treatment of corneal Arcus

• none if condition is presumed to be simply involutional

• Managed associated systemic disease

  • High cholesterol (medical intervention; referral to PCP)

  • Carotid artery occlusive disease (surgical intervention; STAT referral to neurosurgeon <reduce risk of stroke>)

White Limbal Girdle of Vogt (Vogt limbal girdle)

Innocuous arc-like whitish bands of chalk-like flecks; common condition; prevalence in women

Crocodile Shagreen

Benign, age-related corneal degeneration characterized by gray-white polygonal opacities which resemble crocodile skin; characterized as bilateral condition

Cornea farinata (floury cornea)

Age-related corneal condition characterized by tiny, dust-like corneal opacities

Signs of cornea farinata

Cornea

• “Flour dust” lipofuscin-like deposits

• Color: grey-white or tan-brown

• Located: deep stroma, near Descemet membrane

• Fine & numerous

• Best seen w/ retroillumination of iris

Polymorphic Amyloid Degeneration

Non-heritable condition characterized by non-progressive amyloid deposition

Band Keratopathy

Band like deposition of calcium salts in subepithelial space, Bowman layer, & anterior stroma

Pathogenesis of band keratopathy

Imbalance in calcium & phosphate metabolism, resulting in deposition of calcium phosphate crystals in the cornea

Signs of band keratopathy

• peripheral interpalpebral plaque of calcium deposition (presents nasally & temporally)

• Progression into centrally involved chalky plaque; contains transparent holes & clefts (Swiss cheese appearance)

• Advanced/end stage lesions > nodular, elevated, thickening of calcium plaques

Salzmann’s Nodular Degeneration

Condition characterized by nodules of hyaline tissue localized anteriorly to Bowman’s layer

Corneal pannus

Superficial vascularization & scarring of peripheral cornea due to inflammation which presents past normal peripheral vascular arcade

What are the 2 types of corneal pannus

Mciropannus (1-2 mm) & gross pannus (>2mm)

Spheroidal Degeneration

Corneal degeneration characterized by the presence of irregular proteinaceous deposits w/in corneal stroma, Bowman’s membrane, & subepithelium

Spheroidal degeneration can also be called

Climatic droplet keratopathy

Signs of spheroidal degeneration

Cornea

• Initial stage: amber, interpalpebral, peripheral granules

• Intermediate stage: coalescence of granules, opacification & central involvement

• Advanced stage: transformation to nodule, associated elevation, surrounding stromal haze

Treatment/management of spheroidal degeneration for mild cases

Observation

Treatment/management of spheroidal degeneration in severe cases

• superficial Keratectomy either w/ blade & excimer laser PTK

• Keratoplasty: lamellar vs penetrating

Lipid keratopathy

Corneal opacification secondary to lipid deposition; can be primary or secondary

Primary lipid keratopathy

• least common

• Described as spontaneous (no clear cause)

Secondary lipid keratopathy

• most common

• Frequently associated w/ herpes simplex keratitis & herpes zoster keratitis

Signs of primary lipid keratopathy

Subepithelial deposit

• focal

• White or yellow color

• Feathery edges

• May be described as appearing crystalline

• Avascular

Signs of secondary lipid keratopathy

Subepithelial deposit

• focal

• White/yellow color

• Feathery edges

• May be described as appearing crystalline

• Associated corneal neovascularization

• Areas of lipid keratopathy usually abutting corneal neovascularization

Corneal verticillata is also called

Vortex keratopathy & whorl keratopathy

Corneal verticillata

Golden-brown opacities localized to epithelium layer; condition where deposits in the basal epithelium travel from limbus to corneal center w/ resultant whorl like pattern

chloroquine

Quinolone used in treatment of certain autoimmune connective tissue disease & prophylaxis/treatment of malaria

hydroxychloroquine

Quinolone used in treatment of certain autoimmune connective tissue disease & prophylaxis/treatment of malaria

amidarone

• most common

• Cardiac anti arrhythmic agent

Indomethacin

NSAID used to relieve symptoms in RA & gout

Tamoxifen

Selective estrogen receptor modulator used for prophylaxis & treatment of breast cancer

Corneal verticillata can be secondary to systemic pharmaceutical agents such as

Chloroquine, hydroxychloroquine, amiodarone, indomethacin, tamoxifen

Corneal verticillata can be caused by topical pharmaceutical agents such as

Rhokinase inhibitors (Nertarsudil used for glaucoma treatment)

Fabry Disease

X - linked recessive lysosomal storage disease caused by a deficiency of the enzyme alpha galactosidase A

Angiokeratomas

Small dark/ purple spots of skin