‹#› Embryology /organogenesis/ Development and teratology of sensory organs Embsmall ‹#› 2 •29. An overview of development of the eye. •30. An overview of development of the external, middle and inner ear. •----------------------------------------------------------- • •Eye and ear start to develop at: • • Sulcus opticus (neuroectoderm) •Day 22 • Otic placode (ectoderm) ‹#› 3 eyedevdiasmall eardevdiasmall pimg_715201164340393 EYE EAR Day 22: sulcus opticus (neuroectoderm) otic placode (ectoderm) ‹#› 4 eyedevdiasmall pimg_715201164340393 EYE Sulcus opticus (1) Optic vesicle – cup (2-3) (week 4) ---------------------------------- Lens placode (2) Lens vesicle (2-3) ‹#› 5 DEVELOPMENT of the EYE NEUROECTODERM: OPTIC GROOVE (evagination of prosencephalon) give rise to OPTIC VESICLE (CUP) develops into retina, EYESTALK of optic vesicle give rise to optic nerve ECTODERM: LENS PLACODE a LENS VESICLE and VENTRAL CORNEAL EPITHELIUMÞ MESENCHYME: all other components of the eye (sclera, choroid, ciliary body, iris, vitreous body, cornea except its Þ ventral epith.) Eye1a pimg_715201164340393 ‹#› 6 Development of the eye Smyslové orgány I - 25 sulcus opticus optic vesicles optic cup + lens placode + lens vesicle ‹#› 7 Smyslové orgány II - 2 Smyslové orgány I - 25 pure23r pure23r sulcus opticus redbutn redbutn optic vesicle lens placode optic vesicle + eyestalk sign Ectoderm: lens placode (lens cristalina) Neuroectoderm: optic vesicle ð retina Prosencephalon redbutn redbutn retina: pigment epith. other layers (2-10) Lens ‹#› 8 Smyslové orgány II - 3 Hyaloid artery and vein in choroidal fissure Lens vesicle Surface ectoderm 2 layers of optic cup Retina Optic stalk nervus opticus ‹#› 9 Smyslové orgány II - 4 ‹#› 10 Smyslové orgány I - 26 ‹#› 11 Smyslové orgány I - 27 ‹#› 12 Smyslové orgány I - 28 ‹#› 13 lens Gray864 eyed2 Lens growth is induced by optic vesicle ‹#› 14 Teratology of the eye •Anophthalmia •Microphthalmia •Aphakia •Coloboma (iris, eyelid) •Congenital cataracta or glaucom •Congenital ptosis of eyelid microphthalmia2 6702840f15th McCann_right_eye 2367860225_0f9888400f eyes1 50021X-fx24 no lens 1_1003_5 ‹#› 15 Smyslové orgány II - 18 auricle external tympanic cavity, inner ear acoustic meatus Eustachian tube mesenchyme the 1st the 1st ectodermal tubercules (6) pharyngeal cleft pharyngeal pouch otocyst ‹#› 16 EAR ECTODERM: Otic placode (1) (day 22) Otic pit (2) Otocyst (3-4) The 1st ECTODERMAL cleft: Meatus acusticus eardevdiasmall The 1st ENDEDERMAL pouch: Auditory tube + Tympanic cavity Inner ear: Utriculus + semic. ducts Sacculus + cochlear duct Tympanic membrane Ossicles ‹#› 17 Smyslové orgány II - 7 Otic placode – thickening of ectoderm Otic pit Otic vesicle = otocyst: epithelium of membranous labyrinth, incl. sensory ep. originate from ectoderm Development of the inner ear ‹#› 18 Smyslové orgány II - 8 Otic pit Þ otic vesicle (otocyst) ‹#› 19 Smyslové orgány II - 9 Differentiation of the otocyst into membanous labyrinth: V E N T R A L L Y D O R S A L L Y ‹#› 20 Hertwig276.jpg Membranous labyrinth utricle + semicircular ducts saccule + cochlear duct ‹#› 21 Smyslové orgány II - 20 Bony labyrinth from mesenchyme Cochlea Vestibulum Canales semicirculares Membranous labyrinth from ectoderm – epithelium from mesenchyme –rest (membrana basilaris, perilymphatic spaces and their epithelium) Ductus cochlearis Sacculus Utriculus Ductus semicirculares Ductus et saccus endolymphaticus ‹#› 22 Smyslové orgány II - 10 ‹#› 23 Smyslové orgány II - 13 Development of the outer and middle ear arrobend arrobend arrobend arrobend the first the first ectoderm endoderm cleft pouch Recessus tubotympanicus „ear-drum“ ‹#› 24 Smyslové orgány II - 15 Development of tympanic membrane and cavity Development of the ear ossicles The 1st and 2nd branchial arch: 1 - cartilago Meckeli ð maleus, incus 2 - cartilago Reicherti ð stapes ‹#› 25 invertedfetus Smyslové orgány II - 14 Development of the outer ear from mesenchyme of the 1st and 2nd arch, covered with ectoderm ð 6 tubercles (3 ventral + 3 dorsal) ‹#› 26 Teratology: congenital malformations of the ear •Anomalies of: • •Outer ear: anotia, macrotia, microtia, preauricular protuberances and sinuses, meatus atresia •Middle ear: congenital fixation of stapes •Inner ear: aplasia –hypoplasia of labyrinth (rubeola in mother), salicyl preparates using during the 1st trimester) •Hypacusia or deafness: • • •conductive • • • • •sensorineural (perceptive) • ‹#› 27 end ‹#› 28 Credit given 10.5.2012 Selected lectures Embryol. teratol. ‹#› 29 VESICLES OPTCUPB OPTCUP4 Eye development ‹#› 30 EYEDEV1 OPTCUP11 OPTNRVXS EYELM2 ‹#› 31 Hertwig268.jpg ‹#› 32 Repetition: sensory organs •An overview of structural units of the retina. •Microscopic structure of the retina, synapses between neurons. •Microscopic structure of the sclera and cornea. •Choroid, corpus ciliare, iris. •Dioptric media of the eye (cornea, aqueous humor, lens and vitreous body). •Accessory apparatus of the eye (palpebra, lacrimal apparatus, conjunctiva, extraocular muscles). ---------------------------------------------------------------------------- •Mickroscopic structure of outer and middle ear. •Microscopic structure of inner ear – the organ of balance. •Microscopic structure of inner ear – the organ of hearing (ductus cochlearis, organ of Corti). ‹#› 33 eye_G02_anatomy_label_600 ‹#› 34 cornea1 stroma 1 2 3 4 5 ‹#› 35 iris.jpg (31824 bytes) iris_lens1.jpg (37052 bytes) ciliary1.jpg (65800 bytes) ciliary2.jpg (68047 bytes) ‹#› 36 end ‹#› 37 HUMB1L