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組織學 Histology 台北醫學大學/解剖學科 教授：邱瑞珍 分機號碼：3261 電子郵件信箱：[email protected]

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組織學 Histology 台北醫學大學/解剖學科 教授：邱瑞珍 分機號碼：3261 電子郵件信箱：Rueijen@Tmu.Edu.Tw 組織學 Histology 台北醫學大學/解剖學科 教授：邱瑞珍 分機號碼：3261 電子郵件信箱：[email protected] 1 Special sense – eye 台北醫學大學/解剖學科 馮琮涵 副教授 分機3250 E-mail: [email protected] 2 學習目的 •希望同學知道視網膜之顯微構造 •希望同學知道眼瞼顯微結構 3 參考資料 • Junqueira's Basic Histology, twelfth edition, text and atlas, Anthony L. Mescher, McGraw-Hill Companies 4 Summary • A) eye ball: – tunica fibrosa – cornea and sclera – tunica vasculosa—choroids, ciliary process, iris – tunica interna—retina – Lens – vitrous body • B) accessory structure: – eyelids – lacrimal gland 5 6 7 8 Eye • Wall of eyeball: tunicatunica fibrosafibrosa – cornea and sclera tunicatunica vasculosavasculosa – choroid, ciliary body & iris tunicatunica nervosanervosa – retina & pigmented layer opticoptic nervenerve & oraora serrataserrata • Contents: lens, aqueous humor & vitreous body 9 10 Cornea cornea – transparent, avascular, sensory innervation (CN V1) •• cornealcorneal epitheliumepithelium : non-cornified stratified squamous epi. •• BowmanBowman’’ss membranemembrane : basement membrane •• stromastroma : laminated collagen fibers; muco-polysaccharide matrix •• DescemetDescemet’’ss membranemembrane: basement membrane • endothelium 11 Cornea 12 Sclera sclera – thick c.t. with parallel collagen fibers, insertion site of extrinsic eye muscles • Epi-scleral tissue: loose vascular c.t., attaches conjunctiva • stroma: parallel collagen fibers Corneo-scleral junction (limbus): • trabecular meshwork, • canal of Schlemm (scleral venous sinus) 13 14 trabecular meshwork 15 Choroid choroid – soft and thin c.t. membrane • Supra-choroid layer : numerous elastic fibers and pigment cells •• vascularvascular layerlayer : pigment cells and vessels • choriodo-capillaris layer : rich in capillaries; nutrient retina •• BruchBruch’’ss membranemembrane (lamina vitrea) : collagen fibrils; support retina 16 17 ciliary body & iris ciliaryciliary bodybody – ciliary processes (aqueous humor) • ciliary epithelium (simple low columnar or cuboidal epi.) + ciliaryciliary musclemuscle (circular)(circular) irisiris – continuous with ciliary body (pupil) • pigmented epithelium • dilator pupillae muscles & sphincter pupillae muscles 18 19 20 • Ciliary processes 21 Aqueous humor circulation aqueous humor from capillary of ciliary body → posterior chamber → pupil → anterior chamber → canal of Schlemn → venous sinus 22 23 24 25 lens lens – biconvex crystalline surrounded by a lenslens capsulecapsule • anterior surface lies the lenslens epitheliumepithelium •• lenslens fibersfibers • attach to ciliary body by zonular fibers (suspensory ligaments) 26 27 28 Retina • pigmented epithelium • segment layer of rods and cones: rod cells (dim-light); cone cells (color) • external limiting membrane : junctional complex between visual cells and sustentacular (Muller) cells • outer nuclear layer : nucleus of visual cells • outer plexiform layer : synapes with dendrites of bipolar neurons • inner nuclear layer : cell body of bipolar neurons, horizontal & amacrine cells • inner plexiform layer : synaptic region • ganglion cell layer : multipolar ganglion cells • nerve fiber layer : axons of ganglion cells • inner limiting membrane : basal lamina * macula lutea and fovea centralis * * optic disc = blind spot * 29 30 31 32 33 34 35 36 37 38 39 40 41 Accessory structures of the eye •• EyelidsEyelids – levator palpabrae superioris, tarsal plate, tasal glands and conjunctiva •• LacrimalLacrimal apparatusapparatus – lacrimal glands, lacrimal canal, lacrimal sac & nasolacrimal duct •• ExtrinsicExtrinsic eyeeye musclesmuscles – superior oblique (by CN IV) lateral rectus (by CN VI) superior rectus, inferior rectus, medial rectus & inferior oblique (by CN III) 42 43 Eyelid 44 Conjunctiva 45 Lacrimal gland 46 47 48.
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