07.1 Embryology of the Eye and Ear Flashcards
What forms up the inner ear?
Otic placodes
Auditory vesicles
What forms the middle ear?
1st pharygneal pouch (middle ear cavity + eustachian tube) Arch cartilage (ossicles)
What forms the external ear?
1st pharyngeal cleft forms external auditory meatus
Auricles develop from profilerations within 1st and 2nd pharyngeal arches
Where do the ears move during development?
Initially develop in the neck and then ascend as mandible grows
What can cause middle ear deafness?
1st/2nd pharyngeal arch problems
What can cause inner ear deafness?
Cochlea maldevelopment can result from teratogens, esp. infections agents such as rubella
How does the eye form?
Optic vesicle grows out towards the surface and makes fontact with the optic placode.
Optic placode then invaginate and pinches off.
How does the blood supply to the eye develop embryologically?
Distal hyaloid artery degenerates distally.
proximal portion becomes central artery of retina.
What forms the extraocular muscles?
Preoptic myotomes develop in the eye region to form them
How do the eyes move during development?
Start on the side of the head
Move to the front as the facial prominences grow
What forms when the choroid fissure fails to close?
Coloboma
What can cause congenital cataracts?
Genetic
Rubella
