14. Eye Development Flashcards
1
Q
A
aniridia
- PAX6 gene mutation
- lack of iris tissue or complete absence of the iris
- defect results from: “arrested development of the rim of optic cup”
- associated with: glaucoma, cataracts, and other eye abnormalities
2
Q
A
congenital cataracts
- opaque lens (gray/white)
- usually bilateral
- fairly common and may result from the following:
- genetics, Rubella virus [lens vulnerable b/w 4-7 weeks], toxoplasmosis, congenital syphilis, Down syndrome (trisomy 21), galactosemia (galactose from mik accumulate in blood and tissues)
3
Q
A
congenital glaucoma
- increased IOP due to abnormal development of the canal of Schlemm, iridocorneal filtration angle, or mechniasm of aqueous humor drainage (scleral venous sinus)
- causes: genetics (mutations in CYP1B1 gene) Rubella infection
4
Q
edema due to increased intracranial pressure
reflected into subarachnoid space, surrounding optic nerve (CNII)
A
papilledema
5
Q
What causes this?
A
persistence of the distal part of the hyaloid artery
*eye may be microphthalmic
6
Q
A
colomboma iridis
- cleft in the iris caused by failure of choroid/optic fissure to close in week 7 of development
- may extend into ciliary body, retina, choroid, or optic nerve
- causes: environmental factor, autosomal dominant
7
Q
eye symptoms for congenital infections: Rubella virus
A
cataracts, microphthalmos, glauoma, pigmented retinopathy
8
Q
eye symptoms for congenital infections: Toxoplasma gondii
A
microphthalmia
9
Q
eye symptoms for congenital infections: Venezuelan equine encephalitis virus
A
microphthalmia
10
Q
eye symptoms for congenital infections: Varicella virus
A
cataracts, microphthalmia, optic atrophy
11
Q
derived from mesenchyme/NCC
A
- sclera
- cornea (stroma)
- choroid
- iris (stroma)
- ciliary body (stroma/ciliary muscle)
12
Q
derived from neural ectoderm
A
- retina (optic cup)
- iris (smooth muscle, pigmented epithelium)
- ciliary body (epithelium)
13
Q
derived from surface ectoderm
A
- lens
- cornea (epithelium)
