Emryology of Ear Development Flashcards
Inner ear: auditory placode; auditory pit
Middle ear: tubotympanic recess begins to develop
What week does this take place?
3rd
IE: auditory vesicle (otocyst); semicircular canals begin
What week does this takes place?
4th
OE: primary auditory meatus begins
What week does this take place?
5th
IE: utricle and saccule present; semicircular canals begin
OE: six hillocks evident; cartilage begins to form
What week does this take place?
6th
IE: ductus reunion present; sensory cells in semicircular canals
ME: incus and malleus present in cartilage; lower half of tympanic cavity formed
OE: outer cartiliganeous 1/3 of external canal formed
What week does this take place?
8th
IE: one cochlear coil present; sensory cells in utricle and saccule
OE: auricles move dorsolaterally
What week does this take place?
7th
ME: 3 tissue layers at tympanic membrane are present
What week does this take place?
9th
IE: 2.5 cochlear coils present; nerve VIII attaches to cochlear duct
What week does this take place?
11th
IE: Sensory cells in cochlea; membraneous labyrinth complete; otic capsule begins to ossify
What week does this take place?
12th
ME: cartilaginous stapes formed
What week does this takes place?
15th
ME: ossification of malleus and incus begins
What week does this take place?
16th
ME: stapes begins to ossify
What week does this take place?
18th
IE: maturation of inner ear; inner ear adult size
OE: auricle is adult shape but continues to grow until age 9
What week does this take place?
20th
ME: meatal plug disintegrates exposing tympanic membrane
What week does this take place?
21st
ME: pneumatization of tympanum
OE: external auditory canal continues to mature until age 7
What week does this take place?
30th
