Auditory and vestibular system Auris is Us oton

Auditory and vestibular system Auris, is = Us, oton

Auditory and vestibular system external ear (auris externa) n middle ear (auris media) n internal ear (auris interna) = organum vestibulocochleare n

External ear (Auris externa) n auricle (auricula, pinna) n elastic cartilage external acoustic meatus (meatus acusticus externus) n tympanic membrane (membrana tympanica, myrinx) n

Auricle n helix n n n antihelix n n n crura, fossa triangularis scapha concha auriculae n n crus, spina, cauda (tuberculum auriculare Darwini, apex 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 n extrinsic muscles = facial muscles n n n mm. auriculares (ant. , sup. , inf. ) m. temporoparietalis intrinsic muscles: rudimentary n n n 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 -

Auricle – supply arteries: rr. auriculares ant. a. temporalis superficialis a. auricularis post. a. carotis externa n veins: v. jugularis ext. n lymph: nn. ll. parotidei, mastoidei n nerves: sensory n nn. auriculares ant. from n. auriculotemporalis (ventrocranial 2/3) n r. auricularis n. X. (concha) n n. occipitalis minor (dosrocranial) n n. auricularis magnus (cudal) n

External acoustic meatus (meatus acusticus externus) n n n n porus acusticus externus oblique ventromed. again oblique ventromed. (totally converging ventrally 160º and convex descending, length about 22 mm) outer 2/3 – hyalinne cartilage opened ventrally and caudally (incisurae Santorini), lamina tragi (ventrally) transition – the narrowest point (isthmus) – foreign bodies !!! inner 1/3 – osseous – incisura tympanica Rivini glandulae ceruminosae + sebaceae cerumen – protection tragi (after age 30) skin adheres firmly to perichondrium – little

External acoustic meatus (meatus acusticus externus) supply arteries: similar to auricle + a. auricularis prof. a. maxillaris n veins: v. temporalis superficilais, v. auricularis post. n lymph: nn. ll. parotidei, mastoidei n nerves: r. auricularis n. X. (dorsocaudal part), n. auriculotemporalis r. meatus acustici externi n

Tympanic membrane (Membrana tympanica, Myrinx)

Tympanic membrane structure sulcus tympanicus, incisura tympanica Rivini n 9 x 10 mm, thickness 0, 1 mm, surface 55 mm 2 n anulus fribrocartilagineus n outer surface - thinned epidermis (ectoderm) n layer of dense connective tissue (mesenchyme) n inner surface – simple cuboid epitlelium (endoderm) n

Tympanic membrane Otoscopy Ø umbo m. t. Ø stria mallearis Ø prominetia mallearis Ø plica mallearis ant. + post. Ø light reflex – trigonum Wilde (= cone of light, light reflex, Politzer's luminous cone) Bezold‘s trias: prominentia + stria + reflex pars flaccida Shrapnelli (5 mm 2) x pars tensa - declination (50º sagitally) - inclination (45 º transversally)

Tympanic membrane - supply arteries: n a. auricularis prof. a. maxillaris (outer surface) n aa. tympanicae (inner surface) n lymph: nnl. l. mastoidei, parotidei n nerves: n a. auricularis n. X. n n. auriculotemporalis r. membranae tympanicae n

Střední ucho (Auris media) n n n Středoušní dutina (Cavitas tympani) Středoušní kůstky (Ossicula aditus) Středoušní klouby (Articulationes ossiculorum auditus) Středoušní svaly (Musculi ossiculorum auditus) Sluchová trubice (Tuba auditiva Eustachii)

Tympanic cavity (Cavitas tympani) paries tegmentalis n paries jugularis: prominetia styloidea n paries mastoideus: aditus ad antrum mastoideum, prominetia canalis semicircularis lat. + n. VII. , eminetia pyramidalis, fossa incudis, apertura tympanica canaliculi chordae tympani, antrum mastoideum (+ cellulae mastoideae) n paries caroticus n paries membranaceus n

Tympanic cavity paries labyrinthicus promontorium – first thread of cochlea n sulcus promontorii – plexus tympanicus n fenestra vestibuli (= ovalis) – basis stapedis + membrana stapedia n fenestra cochlae (= rotunda) – membrana n

Tympanic cavity - supply arteries: 4 aa. tympanicae, rr. caroticotympanici n veins: do plexus pterygoideus + sinus petrosus sup. n lymph: nn. ll. parotidei, mastoidei, cervicales profundi, retropharyngei n nerves: n n. tympanicus (n. IX) – sensory + parasympathetic (ganglion tympanicum) n r. pharyngeus (n. V 2) for cartilagineous part of auditory tube n nn. caroticotympanici (sympathetic) n

Auditory ossicles (Ossicula aditus) Malleus (Hammer) n caput n collum n manubrium n processus lateralis n processus anterior

Auditory ossicles (Ossicula aditus) Incus (Anvil) n corpus n crus longum n n processus lenticularis crus breve Stapes (Stirrup) n caput n (collum) n crus ant. + post. n basis

Junctures and articulations (Articulationes ossiculorum auditus) art. incudomallearis (saddle-shape) n art. incudostapedia (ball and socket) n syndesmosis tympanostapedialis otosclerosis – ossification n sometimes both joints are replaced with

Ligaments (Ligg. ossiculorum auditus) n n n lig. mallei ant. (spina o. s. )+ sup. + lat. lig. incudis sup. (fossa i. ) + post. membrana stapedialis (fenestra vestibuli) lig. anulare stapediale (fenestra vestibuli) membrana tympani secundaria (fenestra cochleae)

n Muscles of auditory ossicles m. tensor tympani n n n semicanalis m. t. t. processus cochleariformis manubrium mallei inervace: n. V 3 n m. stapedius n n eminetia pyramidalis collum stapedis innervation: n. VII n. stapedius z pars mastoidea canalis nervi facialis

Tympanic cavity n n n n shape of hourglass– 2 mm at level of tympanic membrane (= mesotympanon) recessus epitympanicus (= atticus, epitympanon, epitympanum) – 6 mm recessus hypotympanicus (hypotympanon) – 4 mm plicae malleares ant. , post. recessus ant. , sup. , post. (= Prussak‘s space) plica chordae tympani, incudialis, stapedialis mucosa – simple cuboid epitlelium (various height) mucous cells olny close to the ositum tubae auditivare !!!

n n Mastoid antrum aditus ad antrum mastoideum (Antrum mastoideum) cellulae mastoideae (developing postnatally – 6 th year of age) n pneumatic type n diploic type n sclerotic type cellulae tympanicae n simple flat epithelium n closely related to sinus sigmoideus n n mastoidectomy

Pharyngotympanic / auditory tube (Tuba auditiva) Tuba auditoria, tuba pharyngotympanica, salpinx, tuba Eustachii n ostium tympanicum n pars ossea (= semicanalis t. a. ) – cellulae pneumaticae n pars cartilaginea – cartilago (lamina med. + lat. , lamina membranacea) – tonsilla tubaria Gerlachi located under the mucosa n in hypertorphy of tonsilla pharyngealis ventilation disturbance (mainly in children) mesotitis n ostium pharyngeum (at level of meatus nasi

Pharyngotympanic / auditory tube (Tuba auditiva)

Pharyngotympanic / auditory tube (Tuba auditiva) Tuba auditoria, tuba pharyngotympanica, salpinx, tuba Eustachii equalizes pressure in pharynx and in tympanic cavity n width 2 mm, length 40 mm n transition of pseudostrstified columnar epithelium into simple columnar n glandulae tubariae, mucous cells – in cartilagineous part n in children: more, horizntal, shorter and wider n

Pharyngotympanic / auditory tube(Tuba auditiva) opening: • m. tensor tympani • m. salpingopharyngeus ? role of m. levator veli palatini unclear ? • Ostmann‘s fat pad

Internal ear (Auris interna) n n organum vestibulocochleare osseous labyrinth (labyrinhtus osseus) n n n vestibule (vestibulum) semicircular canals (canales semicirculares) cochlea internsl acoustic meatus (meatus acusticus internus) spatium perilymphaticum membranous labyrinth (labyrinthus membranaceus) n n labyrinthus vestibularis labyrinthus cochlearis

n Osseous labyrinth (labyrinthus osseus) vestibule (vestibulum) recessus ellipticus (utricularis) n n n crista vestibuli (pyramis vestibuli) recessus sphericus (saccularis) recessus cochlearis n n apertura int. canaliculi vestibuli macula cribrosa superior macula cribrosa media macula cribrosa inferior

Membranous labyrinth(Labyrinthus membranaceus) Vestribular labyrinth (Labyrinhtus vestibularis) utricle (utricuus) n saccule (sacculus) n semicircular ducts (ductus semicirculares) n n ampullae, crura ductus utriculosaccularis, reuniens n macula utriculi, sacculi – membrana statoconiorum (statoconium, striola) n crista ampullaris (sulcus, cupula) n

Otolithic organs saculus et utriculus macula n hair cells n supporting cells n gelatinous layer n otoconia – crystal of Ca. CO n 3 n (otoliths – term for crystal in reptiles)

Osseous labyrith (Labyrinhtus osseus) Semicircular canals (Canales semicirculares) Canalis semicircularis anterior (parallel with axis of petrosal bone) – eminentia arcuata n Canalis semicircularis posterior (perpendicular) n Canalis semicircularis lateralis (horizontal) – prominentia c. s. l. n ampulla ossea (3)

Semicircular canals and ducts membranous ducts in bony canals n receptors in ampullae n cristae ampullares n n n perpendicular to axis of canal gelatinous mass hair cells supporting cells

Hair cells n two types n apical surface: n n n 1 kinocilia more stereocilia basally – synapsis with nerve fibers

Osseous labyrinth (Labyrinhtus osseus) Cochlea cupula, basis (2 and ¾ thread) n scala vestibuli helicotrema scala tympani n canalis spiralis cochleae n n lamina spiralis ossea n lamella vestibularis + spiralis n hamulus l. s. (ends in helicotrema) lamina spiralis secundaria (in first thread only) n apertura interna canaliculi cochleae n

Osseous labyrinth (Labyrinhtus osseus) Cochlea Modiolus basis n lamina n canalis spiralis – ganglion cochleare n canales longitudinales – n. cochlearis n

Osseous labyrinth (Labyrinhtus osseus) Internal acoustic meatus (Meatus acusticus internus) n porus acusticus internus n fundus m. a. i. n crista transversa + verticalis n area n. VII. n area cochlearis – tractus spiralis foraminosus n area vestibularis sup. + inf. n foramen singulare

Membranous labyrinth (labyrinthus membranaceus) Cochlear labyrinth (Labyrinthus cochlearis) scala media = ductus cochlearis n paries vestibularis: membrana vestibularis Reissneri n paries externus: stria vascularis, prominentia spiralis, vas prominens, lig. spirale n paries tympanicus (= membrana spiralis): crista basilaris, lamina basilaris, vas spirale n limbus spiralis: labium limbi tympanici, labium limbi vestibularis, (dentes acustici) n membrana tectoria n Organum spirale Corti

Cochlea

Scala media contains endolymph n lamina basilaris with Corti‘s organ n membrana tectoria covers Corti‘s organ n osseous lamina spiralis n ligamentum spirale n

Corti‘s / spiral organ (Organum spirale) n hair cells external (3 -4 rows) and internal (1 row) n stereocilia on surface n n ends n n inserted in membrana tectoria Nuel‘s space in between supporting cells pillar cells (Corti ) – lay the internal tunnel n phalangeal (Deiters) – cover hair cells n outer supporting – columnar (Hensen) and cuboid (Claudius) n

Endolymph and perilymph endolymph: similar to intracellular fluid stria vascularis scala media ductus endolymphaticus saccus endolymphaticus (blind) veins n perilymph: similar to CSF canalicus cochleae is connected with subarachnoid space n

Internal ear – vascular supply arteries: a. basilaris a. inf. ant. cerebelli a. labyrinthi veins: n vv. labyrinthi sinus petrosus inf. n v. aqueductus vestibuli, v. aqueductus cochleae lymph: replaced with endolymph and

Internal ear - nerves nervus vestibularis – ggl. vestibulare Scarpae n pars superior n n n. utriculoampullaris pars inferior n n n. saccularis n. ampullaris posterior nervus cochlearis – ggl. cochleare Corti !!! bipolar neurons !!!

VIII. - Nervus vestibulocochlearis examination n n tuning-fork examination (Rinné, Weber, Schwabach) examination of nystagmus (9 direction – Hering classification) Romberg – stand with closed eyes Hautant – sit, strecht arms forwards and close eyes Unterberger – close eyes and march on site for 30 s

VIII. - Nervus vestibulocochlearis irritation / palsy n affection of hearing (= hypacusis anacusis ) n deafness (= surditas) tinnitus – humming, screeching , ringing… n dizzines (= vertigo) n involuntary eye movement (= nystagmus) = alternating smooth pursuit in one direction and saccadic movements in the other direction. n n slow-phase – stronger side suppresses the weaker one fast-phase – compenstory movements back – serve for description of nystagmus disorders of stand gait (= ataxia)

Auditory tract I. n n n projection → ascending → sensory 4 -neuron-tract decussated and partly non-decussated 1 st neuron: bipolar cell in ganglion cochleare Corti in shape of spiral n. cochlearis n. VIII splits into two fasciculi nucleus cochlearis ant. + post.

Auditory tract II. 2 nd neuron: pons cells in nucleus cochlearis posterior (depth of tones) et anterior (intensity of tones) – separated with pedunculus cerebellaris inferior → decussatio → lemniscus lateralis → colliculus inferior collateral to: nucleus olivaris superior ( inhibited collaterally from ncl. corporis trapezoidei) → learning of auditory space orientation

Auditory tract

Auditory tract III. 3 rd neuron: mesencephalon cells in colliculus inferior → brachium colliculi inferioris tonotopic arrangement commissura colliculi inferioris 4. neuron: diencephalon - metathalamus cells in corpus geniculatum mediale → lobus temporalis - gyrus temporalis transversus Heschli, area 41, 42

Sluchová dráha – 3 D

Vestibular tract I. • projection → ascending → sensory • 3 -neuron-tract, decussated 1 st neuron: bipolar cell in ganglion vestibulare Scarpae → n. vestibularis → n. VIII • some fibers run as tractus vestibulocerebellaris directus to cerebellum without interpolation 2 nd neuron: cells in nuclei vestibulares pontis → axons into various structures of CNS

Vestibular tract II. – where? n n n cerebral cortex cerebellum RF → fascilitating descending system spinal cord nuclei of oculomotor nerves via paramedian pontine RF n reflex hhad-eye n

Vestibular tract III. – to cortex 3 rd neuron: cells in nuclei ventrales thalami → cerebral cortex • lobus parietalis - gyrus postcentralis (area 2) – primary cortex • parieto-insular cortex (gyrus insularis longus) + lobus temporalis - gyrus temporalis transversus Heschli (area 41, 42)

Vestibular tract III. – to cerebellum tractus vestibulocerebellaris directus vestibulum → corpus juxtarestiforme (via PCI) → nodulus + uvula (ipsilat. ) n tractus vestibulocerebellaris indirectus vestibulum → ncl. vestibulares → corpus juxtarestiforme (via PCI) → lobulus flocclulonodularis + vermis (bilat. ) n

Vestibular tract III. – to spinal cord n ncl. fastigii cerebelli → ncl. vestibularis lat. Deitersi (bilat. ) → tr. vestibulospinalis lateralis → alfa + gama-motoneurons for extensors ncl. vestibularis medialis + inferior → fasciculus longitudinalis medialis → interneurons (+ a -) in cervical spinal cord reflex head-eye n

Examination n otoscopy, otomicroscopy – tympanic membrane n n n n paracentesis, grometes tuning fork examinations vestibuloocular reflex – nystagmus vestibulospinal reflexes (Romberg‘s, Unterberger‘s test) X-ray (Stenvers‘ projection– meatus acusticus internus, Schüller‘s – proc. mastoideus), CT, angiography audiometry BER/BERA (ERA, AEP, ABR) otoakustické emise (z vnějších vláskových buněk)

Symptoms and diseases ear pain = otalgie n dizziness = vertigo n spontaneous ringing and buzzing in ears = tinnitus n nystagmus = rhythmic, oscillating motions of eyes n hypacusis n deafness= surditas n morbus Menière – ions dysbalance n atherosclerosis of a. lybyrinthi n meningitis – most frequent cause of acquired n

Development of vestibulocochlear system 3 sources+ nerve fibers n 1 st pharyngeal pouch, cleft and membrane n mezenchyme of 1 st and 2 nd pharyngeal arch n surface ectoderrm of head n fibers from mesencephalon

Development of external ear n meatus acusticus externus 1 st phryngeal cleft n short in birth (beware of injury!) n n pinna 6 auriculr tubercles (mesenchyme) n mainly from 2 nd pharyngelaarch n n with n contribution of 1 st one as well appendices preauriculares

Development of external ear

Development of middle ear n 1 st pharyngeal pouch n n tuba auditiva et cavum tympani 1 st pharyngeal arch malleus, incus n lig. mallei anterius n m. tensor tympani n n 2 ndst pharyngeal arch stapes n m. stapedius n

Development of middle ear n antrum mastoideum n cellulae mastoideae are not developed at birth n appear at 2 nd year of age n pneumatization finished in 6 th year of age

Development of membrana tympani n outer epithelium from 1 st pharyngeal cleft n inner epithelium from 1 st pharyngeal pouch n mesenchyme from 1 st and 2 nd pharyngeal arch

Development of internal ear beginning of 4 th week – otic placod (ectoderm) n auditory pitch n auditory vesicle (otocyst) n process for ductus + saccus endolymphaticus n dorsal part - utricular n ventral part - saccular n

Development of internal ear n utricular part → : discoid processes → ductus semicirculares n rozšíření v ampulu a vznik krist n n saccular part →: diverticulum ductus cochlearis (getting spiral) n ductus reuniens appears n Corti‘s organ (from wall of ductus cochlearis) n ganglion cochleare appears n

Development of internal ear n surrounding mesenchyme changes into cartilagineous capsula otica n cavities appears inside the capsula → perilymphatic spaces n Week 20 -22: ossification of cartilagineous walls

Case-report 1 male, 28 let n returned back fron holiday in Egypt n otalgia for 3 days n palpation painful n objective examination: tragus sensitive in palpation n otoskopic examination: swollen reddish external acoustic meatus with white matter of n

Case report 1 - diagnosis otitis externa n disease of summer months and bathing n n complications: mainly in diabetes mellitus perichondritis or even destruction of temporal bones

Case report 2 female, 3 years n during night sleep severe pain of right ear, weeping, cannot be calmed, blowing her nose for 2 days n vomitting during examination n temperature 38, 3°C n n otoscopic examinatio: tympanic membrane dark red, without contours, convex

Case report 2 diagnosis n mesotitis (otitis media) acuta l. dx. treatment: paracentesis complications: n perforation of tympanic membrane n mastoiditis thrombosis of sinus sigmoideus n labyrinthitis grometa n (chronic mesotitis)

Case report 3 female, 34 years n feeling of pressure in left ear, sudden hypoacusis, buzzing tinnitushu, rotation vertigo, vomitus n vertigo disapeared, other symptoms persist n objective examination: harmonic vestibular phenomens (signaling prevailing one labyrinth) n audiometry: perceptive hypacusis with n

Case report 3 - diagnosis n Menièr‘s disease n hydrops of labyrinth n pacient will return in one month with same symptoms n dif. dg. : circulation disorders, atherosclerosis, sclerosis multiplex, acoustic neurinoma