The Bony and the Membranous Labyrinth

Total Page:16

File Type:pdf, Size:1020Kb

The Bony and the Membranous Labyrinth The bony and the membranous labyrinth Zsuzsanna Tóth, PhD Semmelweis University, Department of Anatomy, Histology and Embryology The inner ear semicircular canals of bony labyrinth vestibule vestibulocochlear nerve cochlea middle ear auditory tube Location: In the petrous part of the temporal bone. Functions: Parts: • hearing (cochlea, spiral organ of Corti) • bony labyrinth • balance • membranous labyrinth • spacial orientation • ganglia and final branches of the vestibulocochlear nerve (VIII.) The bony (osseous) labyrinth vestibule semicircular canals cochlear branch of semicircular cochlea oval (vestibular) of bony labyrinth nerve VIII. canals window sagittal α frontal ∙ α ~45° α vestibular vestibulocochlear branch of nerve VIII. nerve (VIII.) round (cochlear) internal vestibule window cochlea acustic meatus promontory (base of the cochlea, medial wall of the tympanic cavity) Left osseous labyrinth, lateral view Bony limbs (crura) of semicircular canals (5): superior (vestibular connections) • 3 ampullary crura ampullary osseus crura • 1 simple crus, common crus • 1 common crus elliptical recess spherical recess apex lateral (cupula) posterior simple crus cochlea fenestra vestibuli ampullary osseus crus base fenestra cochleae Interior of the vestibule Maculae cribrosae: • superior, media, inferior, • perforated areas for entering the branches of the vestibular elliptical recess nerve: ( for the utricle) 1. utriculoampullar nerve, spherical 2. saccular nerve, recess ( for the saccule) 3. posterior ampullary nerve semicircular canals fossa orifice of the vestibular cochlearis vestibular crest aqueduct Interior of the right osseous labyrinth The cochlea I. m: modiolus: • longitudinal canals of modiolus, one bigger and several smaller channels, vessels, spiral canal of cochlea cochlar n. • spiral canal of the modiolus; spiral ganglion m scala vestibuli* m scala * tympani *: perilymph secondary spiral lamina osseous spiral lamina (at the lower part only) cochlear duct (endolymph) spiral foraminous tract- filaments of the cochlear nerve exit (fundus of the internal acustic meatus) The spiral canal stria vascularis vestibular membrane (Reissneri) scala vestibuli spiral osseous spiral spiral limbus scala media prominentia lamina cochlear duct internal spiral external sulcus spiral sulcus nerve fibers Organ of Corti basilar crest basilar membrane scala tympani spiral ligament The cochlea II. : scala vestibuli and tympani meet hamulus of the spiral lamina 23/4 turn osseous spiral lamina spiral foraminous tract spiral ganglion (bipolar neurons) 9mm The membranous labyrinth endolymphatic sac endolymphatic duct (*) anterior semicircular duct ant. semicircular canal dura mater vestibular aqueduct os temporale, helicotrema pars petrosa spherical cochlear duct recess elliptical recess spiral canal amp. cupular cecum posterior semicircular duct saccule scala vestibuli * v. amp. ductus reuniens lateral semic. duct lat. semicircular canal of Hansen scala tympani amp. post. semicircular canal cochlear canaliculus • perilymphatic duct v.: vestibule • vein of cochlear canaliculus • connection o the subarachnoid space cochlear recess ampullary limb of (shunt ) vestibular cecum utriculosaccular semicircular ducts duct ampullary osseus limb AJNR 18:881–887, May 1997 0195-6108/97/1805–0881 The membranous labyrinth endolymphatic sac endolymphatic duct (*) anterior semicircular duct ant. semicircular canal. dura mater vestibular aqueduct os temporale, helicotrema pars petrosa spherical recess cochlear duct amp. elliptical recess cupular cecum posterior semicircular duct saccule scala vestibuli amp. ductus reuniens lateral semic. duct lat. semicircular canal scala tympani amp. post. semicircular canal cochlear canaliculus • perilymphatic duct • vein of cochlear canaliculus fenestra • connection o the subarachnoid space cochleae • (shunt ) fenestra ampullary limb (crista) of secondary tympanic stapes vestibuli semicircular ducts membrane (oval window) ampullary osseus limb Interior of the vestibule Maculae cribrosae: • superior, media, inferior, • perforated areas for entering the elliptical recess branches of the vestibular (utricle) nerve: spherical recess 1. utriculoampullar nerve, (saccule) 2. saccular nerve, 3. posterior ampullary nerve vestibular crest cochlear recess vestibular aqueduct (end of the cochlear duct ) (endolymphatic duct) Interior of the right osseous labyrinth The membranous labyrinth-sensory epithelia, nerves, blood supply vestibular ganglion ( of Scarpa) utriculoampullar n.: superior and inferior-bipolar neurons ant. ampullar n. cristae ampullaris vestibular nerve lat. ampullar n. utricular n. vestibulocochlear nerve cochlear nerve macula utriculi macula sacculi posterior ampullary nerve vestibularis saccular nerve Blood supply: common cochlear artery basilar artery labyrinthine arteries anterior vestibular artery labyrinthine veins, v. of aqueduct of vestibule,v. of aqueduct of cochlea → inf. petrosal sinus → sigmoid sinus The internal acustic meatus facial canal (facial nerve) medial lateral area superior vestibular area facialis (utriculoampullar nerve) cochlear area transverse (falciform) cochlear nerve crest spiral foraminous inf. tract vestib. area saccular nerve foramen singulare (post. ampullary nerve) fundus of the internal acustic meatus The right internal acoustic meatus and its fundus, medial view. The posterior wall has been partially removed. The endo- and perilymph Perilymph: • fills the bony labyrinth protecting the membranous one p • is produced by the microvasculature of the periosteum • is drained by the perilymphatic duct into the e subarachnoideal space p • similar to the extracellular fluid or the CSF fenestra e vestibuli Endolymph: fenestra e rotunda • fills the membranous labyrinth, p • is produced by the stria vascularis (cochlea) and by the dark cells in semicircular duct SV. • is drained by the endolymphatic duct into the dura ST. mater venous sinuses • similar to the intracellular fluid ions: Sound waves in the perilymph, pressure equilibration: bicarbonate base of the stapes→fenestra vestibuli → scala vestibuli perilymph cloride → cochlear duct and helicotrema → scala tympani perilymph → potassium fenestra rotunda → secondary tympanic membrane sodium Special features of the endolymph are necessary for the sensory functions RMP = 0 mV [K+] = 3 mM • endolymph: very high (150mM) K+ and low (1mM) Na + content • endocochlear potential (EP): scala media is +80mV relative to scala tympany • EP is generated by the stria vascularis. • A strong driving force exists for K + to flow into the receptor (hair) cells (120mM K +, -40mV) during stimulus - depolarization. • The large driving force for K + entry contributes to extremely low threshold of auditory hair cells. • A recycling system allows returning of K + to the stria vascularis. • Energy (ATP) saving for hair cells: K + enters end exits the cell according to the concentration gradient. Stria vascularis - generation of the endocochlear potential stria vascularis ZO ZO GJ • epithelial barriers between the endo- and perilymph: potential K+ conc. 1. basal (B) and intermedier cells GJ 2. marginal (M) cells supported by tight junctions (ZO) • communication: gap junctions (GJ) between B, I cells and fibroblasts (F) in the spiral ligament • intrastrial space: an extracellular fluid compartment with a dense capillary network • endocochlear potential generation: B cells, KCNJ10 NKCC1 potasium channels-mutation: EAST syndrome • K+ ion concentration gradient generation: M cells, no further EP generation because of Cl- ion co-transport Production of the endolymph and K+ ion transport in the semicircular ducts light dark cell cell supporting cell light cell There is no potential, only concentration gradient. The vestibular system 1. Cristae ampullares : 2. Maculae staticae: • in the ampullae of semicircular ducts • in the utricle and saccule • the ridge of the crista is always • they lie in a perpendicular plane to each other perpendicular to the long axis of the duct • detect linear acceleration, tilt of the head and gravity • detect angular acceleration of the head. The structure of the macula sensory epithelium: ototih crystals protein, CaCO3 wall of the otolithic membrane gelatinous substance membranous labyrinth: glycoproteins non-sensory hair cells apical cilia, epithelium rest between the supp. cells squamous and don’t reach the l. propria cuboidal cells, dark secondary sensory cells: and light cells no own axons basal afferent nerves lamina peripheral processes of bipolar neurons in the vestibular ganglion lamina propria connective tissue, reticular lamina vessels, nerve fibers supporting cells a cuticle formed by the union of melanocytes, mechanical support and the apical surfaces of trabeculae-fixation nourishment for hair cells, supporting cells - to the bony labyrinth secretion of otolithic tight junctions membrane components Pattern of membrane potential and firing of the hair cells Resting Resting Resting impulse impulse impulse frequency frequency frequency Stereocilia: Kinocilium: • 30-300pcs/ hair cell, • 1pc/ hair cell • large microvilli, • a real cilium: 9 + 2 array • arranged by size, of microtubules • contain actin filaments, • taller then the • contain fimbrin -rigidity. stereocilia Orientation of cilia - a key of sensitivity to multiple directions striola striola (utricle) saccule kinocilium stereocilia Orientation of kinocilia: • kinocilia are oriented in opposite direction on each side of the striola • utricle - kinocilia are facing the striola
Recommended publications
  • ANATOMY of EAR Basic Ear Anatomy
    ANATOMY OF EAR Basic Ear Anatomy • Expected outcomes • To understand the hearing mechanism • To be able to identify the structures of the ear Development of Ear 1. Pinna develops from 1st & 2nd Branchial arch (Hillocks of His). Starts at 6 Weeks & is complete by 20 weeks. 2. E.A.M. develops from dorsal end of 1st branchial arch starting at 6-8 weeks and is complete by 28 weeks. 3. Middle Ear development —Malleus & Incus develop between 6-8 weeks from 1st & 2nd branchial arch. Branchial arches & Development of Ear Dev. contd---- • T.M at 28 weeks from all 3 germinal layers . • Foot plate of stapes develops from otic capsule b/w 6- 8 weeks. • Inner ear develops from otic capsule starting at 5 weeks & is complete by 25 weeks. • Development of external/middle/inner ear is independent of each other. Development of ear External Ear • It consists of - Pinna and External auditory meatus. Pinna • It is made up of fibro elastic cartilage covered by skin and connected to the surrounding parts by ligaments and muscles. • Various landmarks on the pinna are helix, antihelix, lobule, tragus, concha, scaphoid fossa and triangular fossa • Pinna has two surfaces i.e. medial or cranial surface and a lateral surface . • Cymba concha lies between crus helix and crus antihelix. It is an important landmark for mastoid antrum. Anatomy of external ear • Landmarks of pinna Anatomy of external ear • Bat-Ear is the most common congenital anomaly of pinna in which antihelix has not developed and excessive conchal cartilage is present. • Corrections of Pinna defects are done at 6 years of age.
    [Show full text]
  • Organum Vestibulocochleare INTERNAL EAR MIDDLE EAR EXTERNAL EAR PETROSAL BONE- Eq EXTERNAL EAR AURICLE
    EAR organum vestibulocochleare INTERNAL EAR MIDDLE EAR EXTERNAL EAR PETROSAL BONE- Eq EXTERNAL EAR AURICLE The external ear plays the role of an acoustic antenna: auricle the auricle (together with the head) collects and focuses sound waves, the ear canal act as a resonator. tympanic membrane anular cartilage meatus acusticus externus EXTERNAL EAR EXTERNAL EAR AURICLE scutiform cartilage Auricular muscles: -Dorsal -Ventral -Rostral -Caudal EXTERNAL EAR MEATUS ACUSTICUS EXTERNUS auricular cartilage vertical canal auditory ossicles horizontal cochlea canal auditory tube tympanic tympanic eardrum bulla cavity tympanic membrane MIDDLE EAR Auditory ossicles STAPES INCUS Tympanic cavity: (anvil) (stirrup) - epitympanium - mesotympanium - hypotympanium MALLEUS (hammer) auditory vestibular window- ossicles or oval window through which mechanical stimuli (transmitted by the auditory ossicles) enter the epitympanic internal ear for translation recess into nerve impulses auditory tube (Eustachian tube) cochlear window- or round window tympanic cavity bulla tympanica through which the vibration of the perilympha is absorbed MIDDLE EAR MIDDLE EAR GUTTURAL POUCH- Eq MIDDLE EAR AUDITORY OSSICLES head INCUS processus rostralis (stirrup) STAPES processus muscularis (anvil) manubrium short crus body MALLEUS (hammer) Two muscles of the ossicles: long crus m. tensor tympani- n. tensoris tympani ex. n. base mandibularis (footplate) m. stapedius- n. stapedius ex. n. facialis crus The muscles fix the bones and protect the cochlea crus against the harmful effects
    [Show full text]
  • Ear Development Ear Development
    Ear Development Ear Development The ear can be divided into three parts ◦ External Ear Auricle external auditory canal ◦ Middle Ear tympanic cavity auditory tube auditory ossicles malleus, incus, stapes ◦ Inner Ear Cochlea vestibular apparatus semicircular canals Utricle Saccule Development of Inner Ear All of inner ear derivatives arise from ectoderm Late in 3rd week ◦ otic placode (disc) appears next to hindbrain During 4th week ◦ otic placode form: otic pit otic vesicle or otocyst Young neurons delaminate from ventral otocyst Form statoacoustic (vestibulocochlear) ganglion Rhombencephalon region:formation of otic vesicles Derivatives of the 1st & 2nd branchial arches Rhombencephalon region:otic placode , otic pit and otic vesicle Development of Inner Ear epithelial structures of Otic vesicle develops to membranous labyrinth dorsomedial region elongate to form: ◦ endolymphatic appendage endolymphatic sac rest region expanded to: ◦ pars superior Utricle semicircular canals endolymphatic duct ◦ pars inferior Its ventral tip elongate and coil form cochlear duct differentiate to spiral organ of Corti Its rest gives rise to: Saccule connected to cochlea by ductus reuniens Development of the otic vesicle showing a dorsal utricular portion with endolymphatic duct, and a ventral saccular portion Saccule, cochlea & organ of Corti Outgrowth of cochlear duct-spiral fashion 8th wk.- 21/2 turns Cochlear duct conect with saccule through ductus reuniens Sensory cells of Inner Ear specialized mechanotransducers arise in six prosensory regions within developing otic vesicle ◦ In the cochlea organ of Corti ◦ In the saccule and utricle Maculae ◦ in the semicircular canals Cristae All of these sensory regions innervated by the vestibulocochlear nerve Development of the scala tympani & scala vestibuli Note:the auditory nerve and spiral ganglion Scala media - organ of Corti Hair cells Tectorial mem.
    [Show full text]
  • Balance and Equilibrium, I: the Vestibule and Semicircular Canals
    Anatomic Moment Balance and Equilibrium, I: The Vestibule and Semicircular Canals Joel D. Swartz, David L. Daniels, H. Ric Harnsberger, Katherine A. Shaffer, and Leighton Mark In this, our second temporal bone installment, The endolymphatic duct arises from the en- we will emphasize the vestibular portion of the dolymphatic sinus and passes through the ves- labyrinth, that relating to balance and equilib- tibular aqueduct of the osseous labyrinth to rium. Before proceeding, we must again remind emerge from an aperture along the posterior the reader of the basic structure of the labyrinth: surface of the petrous pyramid as the endolym- an inner membranous labyrinth (endolym- phatic sac. phatic) surrounded by an outer osseous laby- The utricle and saccule are together referred rinth with an interposed supportive perilym- to as the static labyrinth, because their function phatic labyrinth. We recommend perusal of the is to detect the position of the head relative to first installment before continuing if there are gravity (5–7). They each have a focal concen- any uncertainties in this regard. tration of sensory receptors (maculae) located The vestibule, the largest labyrinthine cavity, at right angles to each other and consisting of measures 4 to 6 mm maximal diameter (1–3) ciliated hair cells and tiny crystals of calcium (Figs 1–3). The medial wall of the vestibule is carbonate (otoliths) embedded in a gelatinous unique in that it contains two distinct depres- mass. These otoliths respond to gravitational sions (Fig 4). Posterosuperiorly lies the elliptical pull; therefore, changes in head position distort recess, where the utricle is anchored.
    [Show full text]
  • Titel NAV + Total*
    NOMINA ANATOMICA VETERINARIA FIFTH EDITION (revised version) Prepared by the International Committee on Veterinary Gross Anatomical Nomenclature (I.C.V.G.A.N.) and authorized by the General Assembly of the World Association of Veterinary Anatomists (W.A.V.A.) Knoxville, TN (U.S.A.) 2003 Published by the Editorial Committee Hannover (Germany), Columbia, MO (U.S.A.), Ghent (Belgium), Sapporo (Japan) 2012 NOMINA ANATOMICA VETERINARIA (2012) CONTENTS CONTENTS Preface .................................................................................................................................. iii Procedure to Change Terms ................................................................................................. vi Introduction ......................................................................................................................... vii History ............................................................................................................................. vii Principles of the N.A.V. ................................................................................................... xi Hints for the User of the N.A.V....................................................................................... xii Brief Latin Grammar for Anatomists ............................................................................. xiii Termini situm et directionem partium corporis indicantes .................................................... 1 Termini ad membra spectantes .............................................................................................
    [Show full text]
  • Anatomic Moment
    Anatomic Moment Hearing, I: The Cochlea David L. Daniels, Joel D. Swartz, H. Ric Harnsberger, John L. Ulmer, Katherine A. Shaffer, and Leighton Mark The purpose of the ear is to transform me- cochlear recess, which lies on the medial wall of chanical energy (sound) into electric energy. the vestibule (Fig 3). As these sound waves The external ear collects and directs the sound. enter the perilymph of the scala vestibuli, they The middle ear converts the sound to fluid mo- are transmitted through the vestibular mem- tion. The inner ear, specifically the cochlea, brane into the endolymph of the cochlear duct, transforms fluid motion into electric energy. causing displacement of the basilar membrane, The cochlea is a coiled structure consisting of which stimulates the hair cell receptors of the two and three quarter turns (Figs 1 and 2). If it organ of Corti (Figs 4–7) (4, 5). It is the move- were elongated, the cochlea would be approxi- ment of hair cells that generates the electric mately 30 mm in length. The fluid-filled spaces potentials that are converted into action poten- of the cochlea are comprised of three parallel tials in the auditory nerve fibers. The basilar canals: an outer scala vestibuli (ascending spi- membrane varies in width and tension from ral), an inner scala tympani (descending spi- base to apex. As a result, different portions of ral), and the central cochlear duct (scala media) the membrane respond to different auditory fre- (1–7). The scala vestibuli and scala tympani quencies (2, 5). These perilymphatic waves are contain perilymph, a substance similar in com- transmitted via the apex of the cochlea (helico- position to cerebrospinal fluid.
    [Show full text]
  • Auditory Pathway Inner Hair Cell Afferent Axon 3 500 Efferent Axon 1 Row Contact with Bipolar Cells
    Zdeněk Fík Foramen rotundum myrinx Auris media Auris interna Auris externa A Meatus acusticus externus B Membrana tympani C Cavum tympani D Cochlea E Canalis semicircularis ant. F Tuba auditiva Pinna Elastic cartilage – missing in lobulus Perichondritis Cauliflower deformity -piercing – wrestling fighter compliaction Otapostasis Auricular acupuncture Frank sign Sign of early degeneration of elastic fibres in the skin and vessels. Indicates possible damage of coronary arteries. Griffing G. N Engl J Med 2014;370:e15. Nanda, A., et al. (2011). "Implant-supported auricular prosthesis." Indian J Dent Res 22(1): 152-156. Ear canal Meatus acusticus externus CT horizontal section cavum tympani caput mandibulae cochlea meatus meatus acusticus int acusticus externus celullae mastoideae Ear canal atresia atresia Tragi – hair in the ear canal (adults) • Radchakanta Bažpaj and his 13 cm long tragi – Guinness world record Ear canal irrigation Earwax removal Glandulae ceruminosae Wide and straight ear canal Eardrum 1 - stria mallearis 7 – pars tensa Eardrum - adult 2 – plica mallearis ant membranae 3 3 – plica mallearis post tympani 4 4 – pars flaccida 8 - reflex 6 2 membranae tympani 7 1 5 – umbo Otoscopic view 5 6 - prominentia mallearis 8 Eardrum - child Normal otoscopic view Pathologic otoscopy view Paracentesis RE Hair? neck nape Myringostomy – ventilation tube • Secretory otitis media Pars flaccida Pars tensa Tympanic paraganglioma Middle ear Tympanic cavity stapes malleus incus paries membranaceus paries labyrinticus paries tegmentalis paries jugularis fenestra membrana paries caroticus rotunda tuba paries mastoideus tympani Eustachi Tympanic cavity Fossa cranii media Canalis semicircularis Recessus lateralis epitympanicus M I N. facialis Fenestra ovalis - S vestbuli Membrana tympani Promontory – 1.
    [Show full text]
  • Histology of Ear
    Histology of Ear Histology Department Medical Faculty University of Sumatera Utara 2008 References: Gartner LP, Hiatt JL. Color textbook of histology. 2 nd ed. Philadelphia. WB Saunders company. 2001 Kierszenbaum AL. Histology and cell biology, an introduction to pathology. 2 nd ed. Philadelphia. Mosby Elsevier. 2007 Ear 1. External Ear 2. Middle Ear 3. Inner Ear External Ear Pinna (Auricle) Irregularly shaped plate o/t elastic cartilage covered by thin skin Meatus acusticus externa The canal that extends f/t pinna into the temporal bone to the external surface o/t tympanic membrane Superficial portion is composed of elastic cartilage, which is continuous with the cartilage o/t pinna. Temporal bone replaces the cartilage as support in the inner 2/3 o/t canal Is covered with skin containing hair follicles, sebaceous glands, ceruminous glands (modified sweat glands) Pinna Meatus Acusticus Externus Ceruminous glands Modification of apocrine sweat gland Tubular glands; Produce cerumen (earwax) Myoepithelial cells surrounded the secretory portion of ceruminous glands Middle Ear Tympanic membrane Tympanic cavity Auditory ossicles malleus (hammer) incus (anvil) stapes (stirrup) Auditory (Eustachian) tube Muscle Tensor tympani muscle Stapedius muscle Tympanic membrane External surface is covered by epidermis; Collagen and elastic fibers, fibroblasts interposed btw 2 epithelial layers Internal surface is covered by simple squamous to cuboidal epithelium Tympanic cavity Is an air filled space located i/t petrous portion o/t temporal bone Posterior: mastoid air cell Anterior: auditory (eustachian) tube Medial wall: oval window and round window Lateral wall: tympanic membrane Bony ossicles spans the distance btw tympanic membrane and the membrane o/t oval window .
    [Show full text]
  • Tympanic Membrane (Membrana Tympanica, Myrinx)
    Auditory and vestibular system Auris, is = Us, oton Auditory and vestibular system • external ear (auris externa) • middle ear (auris media) • internal ear (auris interna) = organum vestibulo- cochleare External ear (Auris externa) • auricle (auricula, pinna) – elastic cartilage • external acoustic meatus (meatus acusticus externus) • tympanic membrane (membrana tympanica, myrinx) • helix Auricle – crus, spina, cauda – (tuberculum auriculare Darwini, apex auriculae) • antihelix – crura, fossa triangularis • scapha • concha auriculae – cymba, cavitas • tragus • antitragus • incisura intertragica • lobulus auriculae posterior surface = negative image of the anterior one ligaments: lig. auriculare ant., sup., post. muscles – innervation: n. facialis • extrinsic muscles = facial muscles – mm. auriculares (ant., sup., post.) – m. temporoparietalis • intrinsic muscles: rudimentary – m. tragicus + antitragicus – m. helicis major+minor – m. obliquus + transversus auriculae, m. pyramidalis auriculae cartilage: cartilago auriculae - elastic skin: dorsally more loosen, ventrally firmly fixed to perichondrium - othematoma Auricle – supply • arteries: a. temporalis superficialis → rr. auriculares ant. a. carotis externa → a. auricularis post. • veins: v. jugularis ext. • lymph: nn.ll. parotidei, mastoidei • nerves: sensory – nn. auriculares ant. from n. auriculotemporalis (ventrocranial 2/3) – r. auricularis n. X. (concha) – n. occipitalis minor (dosrocranial) – n. auricularis magnus (cudal) motor: n. VII. External acoustic meatus (meatus acusticus
    [Show full text]
  • Radiology 101 for Audiologists
    8/20/2019 Important Note* Why the ‘eyes are the liars’ Images in this presentation are used with permission from the sources or as set out Relevance of the AVNS in in the rules of use Patient Care and Management They are not to be reproduced without in whiplash & mTBI Patients permission or used for distribution Referencing and acknowledgment of these copyrights are provided Brenda E. Berge, Au.D. , F-ADA Doctor of Audiology, Fellow ADA Membranous Labyrinths Anterior (superior) semicircular canal and duct Ampullae Dura mater Posterior semicircular Endolymphatic sac canal and duct Endolymphatic duct in Common crus and duct vestibular aqueduct Lateral semicircular Utricle canal and duct Saccule Stapes in oval (vestibular) window Helicotrema of cochlea Incus Ductus reuniens Scala vestibuli Malleus Cochlear duct Tympanic cavity Scala tympani External acoustic meatus Tympanic membrane Cochlear aqueduct Round (cochlear) window (closed by Vestibule secondary tympanic membrane) Vestibulocochlear Nerve: Schema Auditory (Eustachian) tube 1 8/20/2019 Inner Ear Superior division of vestibular nerve (from Anterior (superior) utricle and anterior and lateral ampullae) semicircular duct Anterior membranous ampulla Utricle Lateral membranous ampulla Cochlear duct (basal turn) Common membranous Cochlear nerve duct Lateral semicircular duct Vestibulocochlear nerve (VIII) Posterior semicircular duct Vestibular nerve Saccule Posterior Vestibular ganglion membraneous ampulla Endolymphatic duct Inferior division of vestibular nerve (from saccule and posterior ampulla 2 8/20/2019 Axial T2 MRI Cochlea http://www.emedicine.com/ent/images/Large/597REVD622Ccloseupnorm_2.jpg http://www.emedicine.com/ent/images/Large/664698FIG11.JPG Superior Canal Dehiscence http://www.emedicine.com/ent/images/Large/21472147SCDS.jpg 3 8/20/2019 Auriculotemporal Nerve 4 8/20/2019 Muscles of Neck: Anterior View 5 8/20/2019 VCR VSR VESTIBULOCOLLIC VESTIBULO- REFLEX SPINAL REFLEX ACTS ON THE MUSCLES SENDS DESCENDING IN THE NECK TO MOTOR CONTROL STABLIZE THE HEAD.
    [Show full text]
  • Anatomical Studies of Canine Vascular and Ligamentous Ear Structures with Revelance to Acute-Onset Deafness" (2012)
    Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2012 Anatomical studies of canine vascular and ligamentous ear structures with revelance to acute- onset deafness Cathryn Kay Stevens-Sparks Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Medicine and Health Sciences Commons Recommended Citation Stevens-Sparks, Cathryn Kay, "Anatomical studies of canine vascular and ligamentous ear structures with revelance to acute-onset deafness" (2012). LSU Doctoral Dissertations. 1397. https://digitalcommons.lsu.edu/gradschool_dissertations/1397 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. ANATOMICAL STUDIES OF CANINE VASCULAR AND LIGAMENTOUS EAR STRUCTURES WITH RELEVANCE TO ACUTE-ONSET DEAFNESS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Interdepartmental Program in Veterinary Medical Sciences through the Department of Comparative Biomedical Sciences by Cathryn Kay Stevens-Sparks B.S., Louisiana State University, 1993 M.S., Louisiana State University, 1999 August 2012 DEDICATION Many years of undergraduate and post-graduate education have led to the culmination of this work, which would never have been possible without the love and support of my family. This dissertation is dedicated to my late husband, Michael F. Stevens, who was my chief supporter throughout my undergraduate and part of my post-graduate education.
    [Show full text]
  • The Bony and the Membranous Labyrinth
    The bony and the membranous labyrinth Zsuzsanna Tóth, PhD Semmelweis University, Department of Anatomy, Histology and Embryology The inner ear semicircular canals of bony labyrinth vestibule vestibulocochlear nerve cochlea middle ear auditory tube Location: In the petrous part of the temporal bone. Functions: Parts: • hearing (cochlea, spiral organ of Corti) • bony labyrinth • balance • membranous labyrinth • spacial orientation • ganglia and final branches of the vestibulocochlear nerve (VIII.) The bony (osseous) labyrinth vestibule semicircular canals cochlear branch of semicircular cochlea oval (vestibular) of bony labyrinth nerve VIII. canals window sagittal α frontal ∙ α ~45° α vestibular vestibulocochlear branch of nerve VIII. nerve (VIII.) round (cochlear) internal vestibule window cochlea acustic meatus promontory (base of the cochlea, medial wall of the tympanic cavity) Left osseous labyrinth, lateral view Bony limbs (crura) of semicircular canals (5): superior (vestibular connections) • 3 ampullary crura ampullary osseus crura • 1 simple crus, common crus • 1 common crus elliptical recess spherical recess apex lateral (cupula) posterior simple crus cochlea fenestra vestibuli ampullary osseus crus base fenestra cochleae Interior of the vestibule Maculae cribrosae: • superior, media, inferior, • perforated areas for entering the branches of the vestibular elliptical recess nerve: ( for the utricle) 1. utriculoampullar nerve, spherical 2. saccular nerve, recess ( for the saccule) 3. posterior ampullary nerve semicircular canals
    [Show full text]