Exam 1 -- Corneal Dysgeneses Flashcards
1
Q
Describe cornea plana
A
- Flat cornea
- Obscure limbus
- Shallow AC
- Associated with other anterior segment abnormalities
2
Q
Describe microcornea
A
• Adult corneal diameter
3
Q
Describe megalocornea
A
- Adult corneal diameter >13mm
- Inherited, X-linked recessive (males > females)
- Non-progressive
- Symmetric
- High myopia and astigmatism
- Associated with congential glaucoma
4
Q
Describe keratoglobus
A
- Resembles megalocornea
- Cornea thin especially in periphery
- Extremely rare
- Bilateral
- Avoid trauma due to risk of rupture
5
Q
Describe posterior keratoconus
A
- Indentation of posterior cornea
- Variable degrees of central stromal haze
- Normal anterior surface
- Acuity near normal
- Unilateral, non-progressive
6
Q
Describe Peter’s anomaly
A
- Rare developmental anomaly
- Lens protrudes forward, irido-corneal-lenticular adhesion
- Glaucoma in 50-70% of patients
- Central corneal opacification, periphery clear
- Abnormal posterior stroma, Descemet’s, endothelium
7
Q
Describe posterior embryotoxin
A
- Anterior displacement of Schwalbe’s line
- Partial or complete ring in iris near limbus
- Best seen with gonioscopy
8
Q
Describe Axenfeld’s Anomaly
A
- Posterior embryotoxin plus iris strands that run across AC and attach to Schwalbe’s line
- May have iris abnormalities (corectopia)
- Glaucoma risk increased 20-50%
- Anomaly = IOPs normal
- Syndrome = elevated IOP
9
Q
Describe Reiger’s Anomaly
A
- Axenfeld’s anomaly plus iris hypoplasia
- Corectopia
- Corneal defects or strabismus possible
- Anomaly: invovles only the eye
- Syndrome: systemic findings (missing teeth, etc.)
10
Q
Which of the corneal dysgeneses are abnormalities or size or curvature?
A
Cornea plana
Microcornea
Megalocornea
Keratoglobus
11
Q
Which of the corneal dysgeneses are mesenchymal in nature?
A
Posterior keratoconus
Peter’s anomaly
12
Q
Which of the corneal dysgeneses are anterior chamber cleavage syndromes?
A
Posterior embryotoxin
Axenfeld’s anomaly (or syndrome)
Rieger’s anomaly (or syndrome)
