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Flashcards in Embryology Deck (90)
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1

what fibers are included in the fetal nucleus

contains all fibers before birth

2

what type of fibers are in the fetal nucleus

secondary fibers

3

how does the embryonic nucleus form?

posterior epi elongates to fill the lumen
formation of the lens bow

4

what type of fibers are in the embryonic nucleus?

primary lens fibers

5

when do the eyelids fuse and separate?

fuse: month 3
separate: month 5-6

6

lacrimal system: surface ectoderm

nasolacrimal drainage system

7

what is a coloboma?

incomplete closure of fetal fissure in the inferior and nasal aspect

8

when does the optic cup elongates between the lens + cornea

month 3

9

what structures can be involved in an coloboma

optic disc, iris, retina, cb, optic nerve

10

what structures in the iris are formed from neural ectoderm

anterior + posterior iris epi
dilator + sphincter muscle

11

bergmeister papilla

glial tissue persists at ONH
-posterior remnant on lens
-remnants of the fetal hyaloid system
-posterior remnant of the hyaloid system

12

what structure is the retina formed from?

optic cup

13

Mittendorf dot

small, circular opacity on the posterior lens capsule, classically nasal in location, which represents the anterior attachment of the hyaloid artery

14

what is the GCL + INL like at birth?

still thin layer across fovea

15

when are the GCL + INL completely displaced from fovea

4 months post birth

16

what is corneal curvature

-circular + steep (55D) @ birth
-decreases to 40D 6mo after birth

17

what is the first step in corneal development and when does it happen

day 33- corneal epi from surface ectoderm

18

aniridia

absence of iris- altered depth of focus

19

iris: neural crest cells

iris stroma

20

when does myelination reach the chiasm? lamina cribosa?

chiasm: 6 mo

21

what is the horizontal raphe

wraps around mac bundles to get back to optic disc --> brain
-horizontal raphe is temporary

22

when does myelination reach lamina cribosa?

LC: 1-3 mo after birth
-visual implications, foveal displacement, cone development, myelination

23

where does myelination travel from and to

from brain --> eye
LGN --> lamina cribosa

24

horizontal raphe fibers

inferior and superior fibers dont cross
if damage to NFL - VD respects midline

25

inferior damage in horizontal raphe

superior VFD

26

where does maturation of PR occur

fovea + macula

27

what is in hollow eye ball

empty space filled w/ CSF
continuous w/ 3rd V

28

mesenchyme iris

anterior border layer

29

how long can iris darken

6 mo after birth
bc --> blood to cornea

30

hyaloid artery system process

hyaloid artery (ICA branch) enters optic cup through fetal fissure, filling the vitreous cavity, supplies nutrients to lens