Block 15: Lectures 4-6 Flashcards
In what age group does keratoconus typically present?
Teens and 20’s
Is keratoconus usually unilateral or bilateral?
Unilateral initially and becomes bilateral over time
What is the cause for blurred vision in keratoconus?
Irregular astigmatism
What is a rupture or tear in Descent’s Membrane that allows a sudden influx of aqueous into the cornea called?
Acute hydrops
What type of reflex is seen upon retinoscopy on a keratoconus patient?
Scissor reflex
What type of reflex is seen upon ophthalmoscopy on a keratoconus patient?
Oil droplet
Define “Vogt Striae” that are commonly seen when examining an individual with keratoconus?
Vertical stress lines deep within stroma that disappear when pressure is applied to globe
What is it called when the cornea takes a “cone-like” appearance that is observable from a side view or against the lower lid in downsize?
(Name the feature/sign, not the condition it may be associated with)
Munson sign
What location/direction does the protrusion or “cone” ultimately progress to on the cornea in keratoconus?
Infero-temporal
If present, where is Fletcher’s ring usually located on a keratoconus patient?
What filter on slit lamp allows best view of this?
Base of “cone”
Cobalt blue filter
What are 2 tests commonly used to confirm keratoconus?
- Keratometry
2. Corneal topography
What is the difference between an individual with keratoconus who has no complaints of plain and another keratoconus individual who has pain and photophobia?
Pain and photophobia signifies a ruptured Descemet’s Membrane (“Acute hydrops”)
Why might corneal cross-linking be used as a treatment strategy in keratoconus?
To stiffen collagen - stabilize and maybe even reverse the ectasia
What day to day motion involving the eye should an individual with keratoconus avoid?
Eye rubbing
What is a common keratometry reading on an eye with keratoconus?
50.00 D and above
What type of intracorneal implants might be used as a treatment/management option for keratoconus?
Ring segments
Which layer of the cornea becomes edematous with Acute Hydrops?
Stroma
How long does it typically take Acute Hydrops to spontaneously heal?
2-4 months
What can be used to draw fluid out of epithelium in Acute Hydrops?
Hypertonic saline drop
What are 3 options that could be used to manage pain and discomfort in acute hydrops?
- Cycloplegia
- Bandage contact lens
- NSAID
What surgical procedure may accelerate recovery and reduce scarring in Acute Hydrops?
Injection of anterior chamber (intracameral) with gas/air
Name the condition that involves peripheral corneal thinning from 4:00-8:00 without apical protrusion.
Pellucid marginal degeneration
What pattern is classically seen on a topography map in an individual with Pellucid Marginal Degeneration?
Butterfly or Kissing Birds
Although surgery is difficult in Pellucid Marginal Degeneration, what is currently the most favored technique?
Peripheral lamellar crescentic keratoplasty followed by central penetrating keratoplasty
What is a key differentiating feature between Keratoconus and Keratoglobus?
The shape of the corneal ectasia - cone in keratoconus and globular in keratoglobus
Where is the corneal thinning and protrusion typically located in Keratoglobus?
Diffuse
Name two conditions that intrastromal ring segments and corneal cross-linking have a helpful benefit.
Name one condition that they are not effective in treating/managing.
Beneficial:
- Keratoconus
- Pellucid Marginal Degeneration
Not Effective:
1. Keratoglobus
Which condition is most difficult to manage/treat?
Keratoconus, Pellucid Marginal Degeneration, or Keratoglobus?
Keratoglobus - spectacles and contact lenses often cannot correct vision and surgery is very difficult and often ineffective
What is a genetic eye disorder in which abnormal material often accumulates in the cornea and is usually progressive? (General term)
Corneal dystrophy
How are most forms of corneal dystrophies inherited?
Autosomal dominant
Are most corneal dystrophies bilateral or unilateral?
Bilateral
What is the international classification of a corneal dystrophy based on?
The affected chromosomal loci and it’s gene and mutation
What is the typical inheritance pattern in Epithelial Basement Membrane Dystrophy?
Sporadic (much more commonly than Autosomal dominant)
Where is the accumulation of material in Epithelial Basement Membrane Dystrophy?
Between basement membrane and Bowman’s layer
“Maps, dots, and fingerprints” are often used to describe signs seen in what condition?
Epithelial Basement Membrane Dystrophy
Where are the intraepithelial cysts most prominent in Meesmann’s Epithelial Dystrophy?
Interpalpebral zone
What is bowman’s layer replaced with in Reis-Bucklers’ Corneal Dystrophy?
Connective tissue bands
What feature of Reis-Bucklers’ Corneal Dystrophy typically spontaneously presents during early childhood?
Recurrent corneal erosions
What is considered a less severe version of Reis-Bucklers’ Corneal Dystrophy?
Thiel-Behnke corneal dystrophy
What treatment option should usually be tried before keratoplasty in Reis-Bucklers’ Corneal Dystrophy?
Laser keratectomy
What makes keratoplasty less ideal and saved for last option in Reis-Bucklers’ Corneal Dystrophy?
Condition can recur on the graft
How do the connective tissue bands appear in Reis-Bucklers’ Corneal Dystrophy?
Coarse grey/white subepithelial deposits
What layer of the cornea are deposits found in Lattice Corneal Dystrophy?
Stroma
What abnormal material accumulates in Lattice Corneal Dystrophy?
Amyloid
What could be the cause of progressively impaired vision in Lattice Corneal Dystrophy?
Filamentous appearance of amyloid deposits across cornea
How is opacification usually treated in Lattice Corneal Dystrophy?
Penetrating or lamellar keratoplasty
What condition is characterized by white deposits resembling sugar granules that gradually coalesce?
Granular Corneal Dystrophy
What substance is accumulated in Granular Corneal Dystrophy?
In what layer of the cornea?
Hyaline
Stroma
What are the two types of Granular Corneal Dystrophy referred to as?
Type 1: Classic
Type 2: Avellino
What feature does Type 2 (Avellino) Granular Corneal Dystrophy have that Type 1 does not?
Hyaline + Amyloid deposits
Type 1 has Hyaline only
What is an example of an autosomal recessive corneal dystrophy that is relatively common in Iceland?
Macular Corneal Dystrophy
What material is accumulated in Macular Corneal Dystrophy?
Glycosaminoglycans
How is Macular Corneal Dystrophy usually treated?
Penetrating keratoplasty
A disorder of _______ metabolism is responsible for the deposits found in Schnyder Corneal Dystrophy?
Lipid
What material accumulates in Schnyder Corneal Dystrophy?
Phospholipids and cholesterol
What treatment is used for Schnyder Corneal Dystrophy?
Excimer/laser keratectomy or keratoplasty
Accelerated endothelial loss is called ______?
Fuchs’ Endothelial Dystrophy
What is the typical inheritance pattern for Fuchs’ Endothelial Dystrophy?
Sporadic
When is the blurred vision typically worse in Fuchs’ Endothelial Dystrophy?
Morning
Specular reflection typically shows the appearance of what sign in earlier phases of Fuchs’ Endothelial Dystrophy?
Guttata
In Fuchs’ Endothelial Dystrophy, “guttata” often progress to what clinical sign?
“Beaten metal” appearance of endothelium
What effect is seen first in Fuchs’ Endothelial Dystrophy, stromal or epithelial edema?
Stromal edema, causing blur
What clinical sign is apparent when Fuchs’ Endothelial Dystrophy has progressed from stromal blur to epithelial?
Microcysts/bullae
What would be the cause of acute pain in later stages of Fuchs’ Endothelial Dystrophy?
Rupturing microcysts/bullae causing exposed nerve endings
Why might a hairdryer be used to manage Fuchs’ Endothelial Dystrophy?
To dehydrate cornea
What two surgical procedures have a high success rate in Fuchs’ Endothelial Dystrophy?
- Posterior lamellar keratoplasty
2. Posterior penetrating keratoplasty
How would cataract surgery affect Fuchs’ Endothelial Dystrophy?
Cataract surgery would make it worse due to loss of more endothelial cells
What is included in a “triple procedure” for a patient with Fuchs’ Endothelial Dystrophy?
- Cataract surgery
- Lens implantation
- Keratoplasty
What are 3 ways to dehydrate cornea in Fuchs’ Endothelial Dystrophy?
- 5% NaCl drops/ointment
- Decrease IOP
- Hairdryer
What cells are abnormally developed in Posterior Polymorphous Corneal Dystrophy?
Endothelial cells
Abnormal endothelial cells have the characteristics of what type of cell in Posterior Polymorphous Corneal Dystrophy?
Epithelial
What two conditions should be watched for in Posterior Polymorphous Corneal Dystrophy?
- Peripheral anterior synechiae
2. Glaucoma
What are 3 appearances the endothelial lesions may have in Posterior Polymorphous Corneal Dystrophy?
- Vesicular
- Band-like
- Diffuse
If opacification occurs in Posterior Polymorphous Corneal Dystrophy, what treatment is preferred?
Deep lamellar keratoplasty
What is an involutional (age-related) change to the eye that tends to affect the peripheral portion of the cornea more than the central? (General term)
Corneal Degeneration
Are corneal degenerations more often unilateral or bilateral?
Unilateral (asymmetric when bilateral)
Lipid deposits in a circumferential stromal band seen in a young patient with dyslipidemia is known as ______? (specific!)
Corneal Arcus - Arcus Juvenilis
Lipid deposits in peripheral stroma in an elderly patient without any predisposing systemic condition is known as ______? (specific!)
Corneal Arcus - Arcus Senilis/Gerontoxon
What is a key difference between corneal lipid deposits in Schnyder Corneal Dystrophy and Corneal Arcus (Sinilis)?
Location of deposits
- Central in Schnyder corneal dystrophy
- Peripheral in Arcus Sinilis
If an elderly patient has unilateral Corneal Arcus with no other known conditions, what should be checked for?
Carotid disease on the uninvolved side
What is the condition that presents in the majority of those over 40 years old as peripheral interpalpebral whitish crescents?
Vogt Limbal Girdle
Vogt Limbal Girdle has histological changes similar to _____?
- Pinguecula
2. Pterygium
Where are the deposits found in Corneal farinata?
Deep stroma, most prominent centrally
What illumination technique is best for observing Corneal Farinata?
Retroillumination
What layer of the cornea is most frequently involved in Crocodile shagreen?
Anterior 2/3 stroma
What condition is characterized by grayish-white polygonal stromal opacities separated by relatively clear spaces?
Crocodile shagreen
What condition is defined by deposits of calcium within and adjacent to Bowman’s layer?
Band Keratopathy
What material is deposited in the cornea in Band Keratopathy?
Which layer of the cornea?
Calcium
Bowman’s Layer
Where does the plaque of calcium typically begin forming in Band Keratopathy? (not referring to layer of cornea)
Nasal and temporal, extending centrally
What are two ways Band Keratopathy could be ocular-caused?
- Chronic inflammation/edema
2. Silicone oil in Anterior chamber
When is treatment indicated in Band Keratopathy?
When decreased vision and pain are present, due to epithelial breakdown
If treatment is needed for Band Keratopathy and the treating doctor uses EDTA during the procedure, what procedure was most likely performed?
Chelation
Other than calcium, what else could be elevated in serum levels if a metabolic defect is the cause of Band Keratopathy?
Phosphate
What forms nodules in Salzmann’s Nodular Degeneration?
Hyaline
A rare autosomal recessive disorder that results in the accumulation of cystine crystals in many organs throughout the body is known as _____?
Cystinosis
What are the three forms of Cystinosis?
- Infantile
- Late-onset juvenile
- Adult
Which form of Cystinosis typically does not involve renal failure?
Adult
What part of the cornea does Cystinosis start and then progress to?
Starts in anterior periphery and extends posteriorly and centrally as it progresses
How might earlier onset forms of Cystinosis affect ocular tissues in ways that late-onset might now?
Pigmentary retinopathy
What treatment is given as soon as possible after diagnosis of infantile or juvenile cystinosis?
Oral cysteamine
A rare autosomal recessive condition involving abnormal deposition of copper in the liver, brain and cornea is known as ____?
Wilson Disease
What is the most common ocular manifestation of Wilson Disease?
Kayser-Fleischer ring
What are two systemic manifestations commonly seen in Wilson Disease?
- Liver dysfunction
2. Parkinsonism
What layer does copper accumulate in with Wilson Disease?
Descent’s membrane - around corneal limbus
Are Kayser-Fleischer rings more commonly present when there is neurologic involvement or liver involvement?
Neurologic (Greater than 90%)
What clinical finding in the lens is also associated with Wilson disease?
Sunflower cataract
What are three systemic treatments for Wilson Disease?
- Penicillamine
- Zinc
- Ammonium tetrathiomolybdate
What is an X-linked recessive disorder in which an enzyme deficiency leads to tissue accumulation of a glycolipid?
Fabry disease
What is an early ocular sign that most patients develop in Fabry Disease?
Vortex keratopathy (Cornea Verticillata or Whorl Keratopathy)
Why is the diagnosis Fabry Disease often overlooked until later in life?
Early signs/symptoms often dismissed as “growing pains”
Episodic pain in hands/feet during childhood
If a diagnosis of Fabry Disease has been missed (when the individual does in fact have it), what may lead to a diagnosis when the patient reaches 30-40?
Kidney or heart problems
What medications can be used to treat Fabry disease?
Pain meds and ERT
A wedge or spoke-shaped posterior cataract is known as ______?
Fabry cataract
