Development of Eye and Ear

1. DEVELOPMENT OF THE
EYE
(Page 185)
Dr.Sherif Fahmy

2. Anatomy of The Eye
Dr.Sherif Fahmy

3. Ciliary body
Iris CorneaLens
Sclera
Choroid
Retina
Anterior
Chamber
Vitreous humour
Optic nerve
Posterior
chamber
Coats: outer,
middle and inner.
Dr.Sherif Fahmy

4. Development of the eye
• -Starts at the beginning of the 4th
week.
• -Bilateral diverticulum from forebrain at level of
diencephalon.
• -This diverticulum forms optic vesicle and optic
stalk.
• -Optic vesicle will be optic cup which form retina,
iris and ciliary body. The mouth of the cup will form
pupil.
• Inner layer of the cup forms nervous layer of retina
while the outer layer forms the pigmented layer of
retina.
• Optic stalk forms optic nerve and invaginated by
hyaloid artery which will be central retinal artery.
Dr.Sherif Fahmy

5. -Lens placode is formed from thickened surface
ectoderm. It becomes invaginated to form lens
vesicle. At 5th
week, lens vesicle loss contact
with surface ectoderm and enters through the
mouth of optic vesicle.
-Cornea is developed from surface ectoderm
and underlying mesoderm.
-Sclera and choroid are developed from
mesoderm around optic cup.
-Vitreous body is developed from mesoderm
that fill optic cup.
-Eyelids are developed from ectoderm and
mesoderm that covers the cornea.
Dr.Sherif Fahmy

6. Lacrimal Apparatus
• Lacrimal gland: Formed from a group of
ectodermal buds that are formed in the upper
lateral angle of conjunctival sac. The buds
fuse together and become canalised.
• Lacrimal sac & nasolacrimal ducts: are
formed from cord of ectodermal cells
between frontonasal process and maxillary
process.
Dr.Sherif Fahmy

7. Dr.Sherif Fahmy

8. Dr.Sherif Fahmy

9. Dr.Sherif Fahmy

10. Dr.Sherif Fahmy

11. Dr.Sherif Fahmy

12. Congenital anomalies of the eye
• 1- anophthalmia. Absence of the eye.
• 2- Microphthalmia: small eye.
• 3- Cyclopia: single eye.
• 4- Congenital cataract: whitening of the
lens.
• 5- Congenital aphakia: absence of the
lens.
• 6- Coloboma iridis: cleft iris.
Dr.Sherif Fahmy

13. THE EAR
• External & middle ears see
pharyngeal apparatus.
• Internal ear is formed by
formation of otic vesicle from
surface ectoderm.
Dr.Sherif Fahmy

14. Dr.Sherif Fahmy

15. Dr.Sherif Fahmy

16. Dr.Sherif Fahmy

17. Dr.Sherif Fahmy

18. Dr.Sherif Fahmy