2-20 - CornealDegen+Dystrophy+Trauma Flashcards
Arcus senilis
- White perilimbal band w/ clear zone
- Deposition of phospholipid/cholesterol at stroma.
- Age-related (but if young patient, may indicate high cholesterol)
- Asymptomatic, no treatment needed
- Common
Arcus juveniles
- Rare
- Can involve only sector of peripheral cornea
- Can be associated w/ genetic high blood cholesterol.
Vogt’s limbal girdle
- Subepithelial degeneration w/ or w/o calcium deposits
- Common
- Age-related
- Asymptomatic, no treatment needed.
Dellen
- Localised thinning of peripheral cornea parallel to limbus
- Dehydrate + compacted stroma
- Due to tear film local instability (common in RGP CLs)
- Fluorescein pools w/o epithelial damage
- If longstanding, scarring and vascularisation possible.
Band keratopathy
- Calcium deposition in subepithelial space, bowman’s layer, and anterior stroma.
Due to either: - Age (idiopathic)
- Chronic ocular inflammation
- Metabolic disturbance
- Hereditary
Symptoms (if any): - Vision affected if central
- Ocular irritation
Signs: - Plaque of calcium deposits (generally nasal/temporal but can extend centrally)
- Small holes or clefts at plaque possible.
Terrien’s marginal degeneration
- Non-inflammatory progressive thinning of peripheral stroma
- Idiopathic
- Epithelium fine
- Asymptomatic early on + slow progression
- Vascularisation associated possible
- Irregular astigmatism can decrease vision.
- Bilateral, rare but more common in young men
Mooren’s ulcer
- Rare type of ulcerative keratitis
- Uni or bilateral
- Autoimmune to stroma?
2 forms: - Aggressive in young african descent
- Less severe in older white men
Symptoms: - Redness
- Pain
- Photophobia
- Vision decrease
Signs: - Progresses circumferentially + centrally
- Epithelial defect
- Healing associated w/ corneal thinning, vascularisaton, and scarring.
Roscaea keratitis
Rosacea:
- Skin disease w/ bufferfly rash pattern
- Itching, flushing of skin
- Common, idiopathic
- Worse w/ sun exposure
- Common to have dry eye + blepharitis
- Mild to severe
Sometimes associated w/
- Marginal keratitis
- Neovasc
Recurrent corneal erosion syndrome
RCES
- Epithelium to BM attachment instable
- Uni/bilateral
- Idiopathic
Either:
- Dystrophic RCE associatd w/ corneal dystrophy
- Post-traumatic RCE – following superficial corneal trauma.
Symptoms:
- Recurrent sharp ocular pain when waking (epithelium rips off BM)
- Variable duration
- Blurred vision
- Lacrimation
- Photophobia
Signs:
- Localised epithelial irregularities (may see detached epithelial pathc)
- Microcysts after healing (maybe raised)
Epithelial basement membrane dystrophy
EBMD
a.k.a. “Map-dot Fingerprint” dystrophy, Cogan’s microcystic dystrophy, or anterior basement membrane dystrophy.
- Due to poor epithelial attachment to abnormal BM
Either:
- Maps - Multilaminar BM extends to epithelium
- Dots – Deep epithelial cells, which normally migrate to surface, are trapped under BM
- Fingerprints – Folds of reduplicated BM within epithelium
- Most common epithelial dystrophy
- Autosomal dominant, but often unaware of family history.
- Asymptomatic, but can affect vision if centre.
- Can be associated w/ (or cause) RCES
Meesmann’s dystrophy
a.k.a. juvenile hereditary epithelial dystrophy.
- Many tiny cysts within epithelium
- Early in life, slow progression
- Autosomal dominant inheritance
- Vision minimal affected
- May develop recurrent erosions.
Symptoms:
- Irritation
- Photophobia
Reis-Bücklers dystrophy
- Damage + scar to bowman’s layer + ant. Stroma
- Irregular bands of collagen progressively replace bowman’s layer in honeycomb pattern
- Sub-epithelial opacities centrally, most dense in mid-periphery
- Rare, bilateral
- Severe, present young
- Hemi-desmosome loss = Recurrent erosion.
Granular dystrophy
- Rare, autosomal dominant
- Small granular deposits of hyaline in central ant. stroma, w/ clear zones between. Peripheral spared, deposits can merge.
- Present within 1st decade
- Decreased vision when opacities merge
- May have recurrent corneal erosions.
Lattice dystrophy
Deposition of amyloid protein in stroma
- Branching refractile lines
- Diffuse ant. stromal haze
- Significant scarring later
Poor epithelial adhesion = painful recurrent erosions
Macular dystrophy
- Central, grey, poorly defined opacities w/ cloudy stroma
- Mucopolysaccharide deposits in stromal keratocytes
- Corneal thinning
- Rare autosomal recessive
- Progessive, vision loss in 1st or 2nd decade w/ needing corneal transplant.
- Does NOT lead to RCES
Fuch’s endothelial dystrophy
- Common, progressive.
- More in women
- Generally autosomal dominant, but recessive possible
- Start at endothelial dystrophy, then becomes Fuch’s dystrophy in 5th/6th decade.
Stage 1 – Corneal Guttata
Stage 2 – Progessivel endothelial loss (due to barrier + active transport breakdown) -> stromal + epithelial oedema.
- Symptoms = Glare, photophobia, blurred vision when waking
- If bullous keratopathy, pain
Stage 3 – Degenerative pannus + scarring + permanent vision loss (requires graft)
Corneal guttata
- Collagen deposits thickens descemet’s membrane (where otherwise would be endothelial cells so endothelial loss)
- Visible under slit lamp w/ specular reflection as “beaten metal”
- Pleomorphism + Polymegathism of endothelium.
Posterior polymorphous dystrophy
- Rare, asymptomatic usually, but if symtpoms, early in childhood.
- Autosomal dominant
- Abnormal endothelial cells (w/ more epithelial phenotype)
- Grouped vesicular/bubble-like lesions on endothelium
- Linear, band-like lesions (snail track appearnace)
- Can cause endothelial compromise -> stormal + eptiehlial oedema
- Endothelial cells can grow into angle -> glaucoma
- Associated w/ iris abonormalities e.g. iridocorneal adehsions.
Acid vs Alkali burns
- Alkali lipophilic so penetrates cornea for more damage
- Alkali kill cell by binding to lipids and disrupting cell membrane
Acute: - Corneal epithelium sloughing, stromal + endothelial necrosis –> stromal oedema.
Long term: - Serious opacification
- Limbal blancing (white) = limbal stem cell loss.
- Poor prognosis
