Embryology

Question 1

Drainage angle

Answer 1

7/40 - neural crest cells from peripheral cornea –> chamber angle
4 mo - Shlemm’s canal
8 mo - drainage angle complete

Question 2

When does the optic fissure close?

Answer 2

Week 7 ( Day 33)

Question 3

Lens Placode

Answer 3

Day 27-29

Question 4

Lens vesicle

Answer 4

Day 30

Question 5

Primary lens fibres

Answer 5

Day 35

Question 6

Embryonic nucleus

Answer 6

Day 40

Question 7

Secondary lens fibres

Answer 7

7 weeks

Question 8

Ciliary body

Answer 8

3rd month in utero

Question 9

Ciliary muscle

Answer 9

7 month in utero

Question 10

Cornea

Answer 10

2 waves of neural crest cells
1st wave - formed between epithelium and lens, forms a double layer of cornea endothelium
2nd wave - between epithelium and endothelium-this zone richly contains hyaluronic acid and collagen fibrils

Question 11

Descemets membrane

Answer 11

4 months IU

Question 12

Bowmans membrane

Answer 12

5 months IU

Question 13

Y lens suture

Answer 13

week 8

Question 14

Optic Groove

Answer 14

Day 22

Question 15

Optic vesicles –> pit

Answer 15

Day 23

Question 16

primordia of superior, inferior, medial rectus and inferior oblique

Answer 16

Day 26

Question 17

Primordial of lateral rectus appears

Answer 17

Day 27

Question 18

Cells destined to become RPE acquire pigmentation

Answer 18

Day 28

Question 19

primordia of superior oblique

Answer 19

Day 29

Question 20

Closure of embyronic fissure

Answer 20

week 6

Question 21

Appearance of ciliary ganglion

Answer 21

Week 6

Question 22

Formation of sclera

Answer 22

Week 7

Question 23

Appearance of anteiror chamber

Answer 23

3 months

Question 24

eyelid folds lengthen and fuse

Answer 24

Month 3

Question 25

differentiation of rods and cones precursors

Answer 25

Month 3

cones fully developed: 6 months

Question 26

Eyelid separation

Answer 26

Month 5

Question 27

photoreceptor differentiation

Answer 27

Month 5

Question 28

Nasolacrimal duct becomes patent

Answer 28

Month 6

Question 29

Rods differentiate, ora serrata formation

Answer 29

Month 7

Question 30

completion of anterior chamber angle formation, hyaloid vessel disappear

Answer 30

Month 8

Question 31

retinal vessels reach temporal periphery, pupillary membrane disappears

Answer 31

Month 9

Question 32

Which vessels are derived from the ventral ophthalmic artery?

Answer 32

Nasal long Posterior ciliary artery

Question 33

Which vessels are derived from the dorsal ophthalmic a?

Answer 33

Temporal long posterior ciliary a
CRA
Short posterior ciliary a

Question 34

When does the eyeball reach its maximum size?

Answer 34

8 years

Question 35

When does myelination of the optic nerve start and finish?

Answer 35

7 month - 1 mo pp