胚胎

網膜虹睫表神經； 外肌外鞏血內皮。
水晶表角結膜淚； 其它都在神經脊。

七言絕句： 好詩！

---

外胚層 (Ectoderm)

表面外胚層 （Surface ectoderm）
Lens
Corneal epithelium
Cojunctiva
lacrimal glands cells

---

視經外胚層 (Neuroectoderm )

optic nerve
Retina (RPE and neurosensory retina)
ciliary epithelium (pigmented and nonpigmented)
Iris muscle : sphincter and dilator
Iris epithelium

神經外胚層–由後往前：
optic nerve→retina→ciliary epithelium→iris muscle+epithelium

---

神經脊( Neural crest)

sclera（teporal之外的大部份）
choroid
stroma of iris
corneal stroma+endothelium
trabecular meshwork
Ciliary muscle

=> cornea,iris,choroid，stroma都在neural crest！

---

* 中胚層 (Mesoderm)
構成：
眼外肌的muscle fiber （sheath與tendon屬於neural crest）
sclera的temporal portion （sclera的其它部份由neural crest構成）
眼部血管的endothelial lining

---

器官整理：
* cornea
epithelium – surface ectoderm
stroma and endothelium – neurocrest

* sclera
temporal portion–mesoderm
其它部份–neural crest

* optic nerve：neuroectoderm

* extraocular muscle
belly – mesoderm
tendon and sheath – neural crest

---

Uvea

* Iris
 Iris muscle (dilator/sphincter)/epithelium – neuroectoderm
 Iris stroma–neural crest

* Choroid – neural crest

* Ciliary muscle – neural crest
 Melanocyte – neural crest
 Trabecular meshwork – Neural crest

* Lens – surface ectoderm

---

* vitreous–mesoderm + surface ectoderm + neuroectoderm （只差沒有neural crest→因為vitreous沒有 stroma）
* Retina–neuroectoderm
* RPE–neuroectoderm

---

Anterior chambers 的形成是經由Neural crest cells migrate分化而來
第1波：形成corneal endothelium（1內）
第2波：形成iris, 部份papillary membrane（2彩）
第3波：形成Keratocytes（3角）

口訣： 跳土風舞：「前一二三…向內踩腳」… 1內，2彩，3角

---

lens embryology:

22天–optic primordium
25天–optic vesicle
27天–lens plate
29天–lens pit
33天–lens vesicle且同時optic vesicle →2 layered optic cup
40天–來至後方的cells elongated→primary lens fiber(embryonic nucleus)→7週至8個月→來至equator的epithelium分化成secondary lens fiber→fetus nucleus

suture–由於lens由外向內分泌fiber，當前後cells相會時，則形成suture，在8週時可見到前有正立Y，後有倒Y結構（前正後倒）

Tunical vasculosa lentis – 分成：
Ant. vascular capsule
 來自long ciliary a.
 形成pupillary strand
 Capsulopupillary portion
Post. vascular capsule
 來自hyaloid a.
 形成Mittendorf dot

zonular fiber在3個月大時由ciliary epithelium來
congenital aphakia – 分primary (根本沒發育)及secondary(發育後又absorb掉)

---

* Mesenchymal structures of the head, including the eye, are all derived from "a combination of neural crest cells and mesoderm"

* The mesoderm gives rise to all vascular endothelia, all extraocular muscles, and temporal sclera