Development of eye

Question 1

Eye development

Answer 1

surface ectoderm: lens

neuroectoderm: retina, optic nerve
mesoderm: vascular and connective tissue tunics of the eye, extra ocular muscles

Question 2

Early eye development

Answer 2

begins at day 22
formation of optic sulci -> optic vesicles
the evagination of optic vesicles induce lens placode
optic vesicle -> optic stalk + optic cup

Question 3

Optic cup and optic stalk

Answer 3

Outer layer of optic cup -> pigmented layer of retina
Intraretinal space -> separates pigment layer from neural layer, becomes potential space, common site for retinal detachment
Inner layer of optic cup -> neural layer of retina
Optic stalk -> optic nerve
Mesoderm around stalk -> meninges, pia-arachnoi, dura
Hyaloid vessels -> central artery and vein of retina

Question 4

Optic nerve

Answer 4

tract of diencephalon
not completely myelinated until 3 month after birth
myelinated by oligodendrocytes (not in retina)
not capable of regeneration
invested in meninges

Question 5

Iris

Answer 5

develops from 2 layers of optic cup(neuroectoderm) and choroid(mesoderm)
contains dilator and sphincter pupillae muscles (neuroectoderm)
outer mesodermal layer of iris -> iridopupillary membrane

Question 6

Ciliary body

Answer 6

from anterior 2 layers of optic cup(neuroectoderm) and anterior choroid (mesoderm)
contains ciliary muscle
ciliary processes- produce aqueous humor, zonule fibers

Question 7

Lens

Answer 7

lens placode -> lens vesicle

posterior cells elongate, lose nuclei -> primary lens fibers (secondary lens fibers continuously added to central core)

Question 8

Vitreous body

Answer 8

from mesodermal cells migrating through choroid fissure

contains hyloid artery -> hyloid canal

Question 9

Cornea

Answer 9

surface ectoderm -> anterior epithelium

mesoderm -> substansia propria, corneal epithelium

Question 10

Sclera and choroid

Answer 10

from mesoderm surrounding optic cup
sclera continuous with dura
choroid continuous with pia-arachnoid

Question 11

Canal of Schlemm

Answer 11

in sclerocorneal junction, limbus

drains aquous humor

Question 12

Innervation of iris, ciliary body and cornea

Answer 12

Sphincter pupillae m. - parasympathetic oculomotor
Dilator pupillae m.- sympathetic superior cervical ganglion
Ciliary m. - parasympathetic oculomotor
Cornea - ophthalmic trigeminal

Question 13

Congenital malformations

Answer 13

Coloboma iridis
Congenital cataracts
Congenital glaucoma
Microphthalmia
Anophthalmia
Cyclopia
Retinocele
Retrolental fibroplasia
Persistent iridopupillary membrane 
Detached retina
Papilledema
Retinitis pigmentosa