Cranial nerves Flashcards

Question

ORBIT (ORBITA)

Answer 1

Contents of the orbit: • eyeball (bulbus oculi) • accessory visual structures: - retrobulbar fat (corpus adiposum orbitae), - fascial sheath of eyeball (vagina bulbi), - partly eyelids (palpebrae) and conjunctiva (tunica conjunctiva) - lacrimal apparatus (apparatus lacrimalis), - extra-ocular muscles - CN2-6 only n.ophthalmicus with branches (n. lacrimalis, n. frontalis, n. nasociliaris), n. zygomaticus and n. infraorbitlais (n. maxillaris) - ganglion ciliare - a. ophthalmica with branches (a. centralis retinae, a. lacrimalis, aa. ciliares posteriores, aa. musculares, a. ethmoidalis anterior et posterior) - a. infraorbitalis - v. ophthalmica superior, v.ophthalmica inferior Communications of the orbit: 1. canalis opticus communicates with fossa cranii media; it transmits n. opticus, a. ophthalmica 2. fissura orbitalis superior - communicates with fossa cranii media; it transmits n.ophthalmicus, n. oculomotorius, n. trochlearis, n. abducens, v. ophthalmica superior and partly v. ophthalmica inferior 3. foramen ethmoidale anterius is between the medial wall and the roof of the orbit (between the frontal bone and the ethmoidal bone); it communicates with fossa cranii anterior and transmits n. ethmoidalis anterior, a. et v. ethmoidalis anterior 4. foramen ethmoidale posterius is between the medial wall and the roof of the orbit (between the frontal bone and the ethmoidal bone); it communicates with cavitas nasi and transmits n. ethmoidalis posterior, a. et v. ethmoidalis posterior 5. canalis nasolacrimalis – canal is between the upper jaw, lacrimal bone and inferior nasal concha; it communicates with cavitas nasalis ossea (meatus nasi inferior); it transmits ductus nasolacrimalis 6. canalis infraorbitalis through foramen infraorbitale leads to facies anterior maxillae; it transmits n. infraorbitalis, a. infraorbitalis 7. fissura orbitalis inferior - communicates with fossa pterygopalatina and fossa infratemporalis - transmits n. zygomaticus, n. infraorbitalis, a. infraorbitalis, v. ophtalmica inferior

Answer 2

- sensory fibres - Before entering the sinus cavernosus, gives off 1. ramus tentorius for tentorium cerebelli (separates cerebellum from hemispheres) (locates in the lateral wall of sinus cavernosus below nervus trochlearis) --> enters the orbit through fissura orbitalis superior and divides into three nerves: 1. n. lacrimalis - runs along w/. a. lacrimalis on the LATERAL wall - communicating branch with n. zygomaticus (from n. maxillaris) - supplies lacrimal gland, conjuctiva, skin at the lateral upper corner of the eye 2. n. frontalis on the UPPER wall a. n. supraorbitalis - larger, passes through foramen supraorbitalis - supplies skin of forehead and upper eyelid b. supratrochlearis - smaller, runs through incisura frontalis - supplies conjuctiva, skin of the forehead; nose root; medial eye, upper eyelid 3. n. nasociliaris - MEDIAL WALL above m. rectus medialis - terminates as *n. infratrochlearis - -> supplies lacrimal sac, conjuctiva and skin of medial angle of the eye - gives off side branches: a. n. ethmoidalis posterior - through foramen ethmoidale posterius - supplies mucous membrane of the nasal cavity, cellulae ethmoidales posteriorres and sinus sphenoidales b. n. ethmoidalis anterior - through foramen ethmoidale anterius to the anterior cranial fossa --> gives off ramus meningeus - descends through lamina cribrosa to the nasal cavity --> rami nasales interni supplies the mucous membrane of the nasal cavity, cellulae ethmoidales, sinus frontalis - terminal: ramus nasalis externus; it pierces the nasal bones and supplies the skin of the dorsum and apex of nose c. n. ciliares longi - b. sclera (fibrous) and choroid (vascular layer) and supplies them - sympathetic fibers from the superior cervical ganglion to musculus dilatator pupillae (some in breves too) d. sensory root for parasympathetic ganglion – radix sensoria ganglii ciliaris – to ganglion ciliare.

Answer 3

sensory - in the middle cranial fossa the nerve gives off * ramus meningeus to supply the meninges of this fossa - from sinus cavernosus through foramen rotundum, enters fossa pterygopalatina 1. n. infraorbitalis – runs through fissura orbitalis inferior to the orbit, passes along sulcus et canalis infraorbitalis, then through foramen infraorbitale emerges on the anterior surface of the maxilla - supplies the skin of the face between the eye and mouth openings by small branches: Pes anserina minor or small goose foot a) r. palpebrales inferiores – skin and conjunctiva of the lower eyelid, b) r. nasales externi – skin of the cheek and lateral surface of the nose, c) r. labiales superiores – skin of the cheek, nasal wing and upper lip d) rr. alveolares superiores anteriores – descend along the anterior wall of sinus maxillaris and supply dentes incisivi, dentes canini, sinus maxillaris - participate in formation of plexus dentalis superior. Plexus dentalis superior lies on arcus alveolaris, supplies the mucosa of sinus maxillaris and gives off rr. dentales superiores and rr. Gingivales superiores for the upper teeth and gums - nn. alveolares superioriores forming e) r. alveolaris superior medius – descends along the lateral wall of sinus maxillaris and supplies dentes premolares and mucosa of sinus maxillaris; it takes part in formation of plexus dentalis superior 2. r. alveolares superiores posteriores – they arise directly from the maxillary nerve, descend along tuber maxillae, run through foramina alveolaria and canales alveolares to form plexus dentalis superior; they supply superior dentes molares 3. n. zygomaticus - passes through fissura orbitalis inferior to the orbit, runs along its lateral wall - communicating branch with n. lacrimalis to glandula lacrimalis; carries postganglionic parasympathetic fibers from ganglion pterygopalatinum, that stimulate fluid secretion from the lacrimal gland --> The sympathetic fibers originate from the superior cervical ganglion and run via n. caroticus internus along BV to inhibit fluid secretion from the lacrimal gland - leaves the orbit through foramen zygomaticoorbitale - divides into 2 branches: a) r. zygomaticofacialis - emerges at the zygomatic region through foramen zygomaticofaciale and supplies the skin over the cheek b) r. zygomaticotemporalis - emerges through foramen zygomaticotemporale - supplies the skin at the anterior part of the temporal region 4. sensory root for parasympathetic ganglion – radix sensoria ganglii pterygopalatini – to ganglion pterygopalatinum. N. Palatinus major - pass through the canalis palatinus major and innervate mucosa of the palatinum durum Nn. Palatini minores - canalis palatini minores and mucosa of the palatinum molle Last one: - pass through foramen sphenopalatinum —> nn. Nasales posterior superioris : lateralis and medialis —> innervates the posterior part of the nasal cavity (lateralis) —> and septum nasii (medialis) —> medialis passes through obliquely along septum nasi and reach canalis incisivus —> n. Nasopalatinus innervates anterior palatum durum

Answer 4

mixed: motor are derivates of the 1st pharyngeal arch - largest division of the trigeminal nerve - leaves the cranial cavity through foramen ovale, enters fossa infratemporalis and passes between m. tensor tympani (medial) m. pterygoideus lateralis (lateral) - arise: a. ramus meningeus – S - returns into the cranial cavity through foramen spinosum (with a. Meningee media and supplies the meninges of fossa cranii media) b. n. pterygoideus medialis – contains motor fibers, goes through ganglion oticum and supplies m. pterygoideus medialis - gives off n. musculi tensoris veli palatini and n. musculi tensoris tympani to supply corresponding muscles (nervus tensor veli palati is the only muscle of the palate not innervated by plexus pharyngeus) c. sensory root for parasympathetic ganglion – radix sensoria ganglii otici – to ganglion oticum - then divides into a small anterior and large posterior trunk

Answer 5

CN1 n. olfactorius

Answer 6

CN2 n. opticus, fossa cranii media

Answer 7

``` CN3: r. superior/inferiorr CN4 CN5a n. opthalamicus: n. nasolacrimalis/lacrimalis/frontalis CN6 Radix sympathica ganglii ciliaris ```

Answer 8

CN5b n. maxillaris

Answer 9

``` CN5c n. mandibulae ganglion oticum below in fossa interpeduncularis n. mandibularis n. petrosus minor plexus venosus foraminis ovalis ```

Answer 10

Vagus group: CN9 CN10 CN11

Answer 11

CN7 CN9 1. n. petrosus major - leaves canalis facialis through hiatus canalis nervi petrosi majoris, enters the middle cranial fossa, - pierces cartilage of foramen lacerum and then through canalis pterygoideus reaches fossa pterygopalatina. The nerve forms parasympathetic root for the parasympathetic ganglion – ganglion pterygopalatinum 2. n. tympanicus (CN9) - terminal part is n. petrosus minor; contains preganglionic PS fibres, leaves the tympanic cavity through hiatus canalis nervi petrosi minoris, enters the middle cranial fossa, then goes through foramen lacerum and forms parasympathetic root for parasympathetic ganglion – ganglion oticum

Answer 12

A: 3M & 1S 1. n. massetericus – pierces musculus masseter from inner side and supplies it 2. nn. temporales profundi – usually are two nerves; pass above crista infratemporalis upward to fossa temporalis and reach m. temporalis to supply it 3. n. pterygoideus lateralis – is short nerve and supplies m. pterygoideus lateralis 4. n. buccalis – S - runs between M. masseter / buccinator - supplies the skin of the cheek and angle of the mouth and mucous membrane lining the inner surface of the cheek

Answer 13

3S - 3M - supply the M. mylohyoideus and venter anterior m. digastrici 1. n. auriculotemporalis - starts by 2 roots surrounding a. meningea media - runs back- and upward, curves collum mandibulae, goes between art. temporomandibularis and meatus acusticus externus - lies in glandula parotis, is accompaning a. temporalis superficialis - terminates by r. temporales superficiales which supply skin of the posterior part of the temporal region, the temporomandibular joint - gives off side branches: a) n. meatus acustici externi – to the skin of the upper part of meatus acusticus externus b) r. membranae tympani – to the tympanic membrane c) r. parotidei – to glandula parotis; they receive postganglionic PS fibres and postganglionic symphatetic fibers from ganglion oticum d) nn. auriculares anteriores – to the skin of the anterior part of auricula, tragus and helix 2. n. lingualis - passes b. m. pterygoideus medialis and ramus mandibulae, then laterally to m. styloglossus and m. hyoglossus - crosses ductus submandibularis and terminates in the tongue by rami linguales - supply the mucous membrane of dorsum linguae from apex to sulcus terminalis and papillae filiformes - The beginning part of n. lingualis has communication with chorda tympani (CN7) and receives from it sensory taste fibers and PS preganglionic fibres. - has side branches: a) nervus sublingualis – supplies the mucous membrane of the mouth cavity and gums b) rami isthmi faucium – supply arcus palatoglossus and tonsilla palatina c) sensory root for parasympathetic ganglion – radix sensoria ganglii submandibularis – to ganglion submandibulare 3. n. alveolaris inferior - descends through foramen mandibulae into canalis mandibulae; it emerges through foramen mentale as n. mentalis and terminates by: a) rami mentales – supply skin of the chin b) rami labiales supply skin of the lower lip c) rami gingivales – supply the gums - In canalis mandibulae the nerve forms plexus dentalis inferior, from which arise: * rami dentales inferiores * rami gingivales inferiores for the lower teeth and gums - before foramen mandibulae motor fibres separate as n. mylohyoideus; it lies in sulcus mylohyoideus and supplies muscles – derivates of the 1st branchial arch on the neck – m. mylohyoideus and venter anterior musculi digastrici.

Answer 14

1. r. meningeus – S fibres - from ganglion superius - passes through foramen jugulare and returns into the cranial cavity - supplies the meninges of the posterior cranial fossa 2. r. auricularis – S fibres - from ganglion superius - supplies the skin of the P part of the auricle and external acoustic meatus, inner Portion of the auricle ``` Cervical part: 3. r. pharyngeus – contains S, M and PS fibres - at the level of ganglion inferius - joins with ramus internus of the accessory nerve; the branch forms *plexus pharyngeus to supply muscles of the palate (except m. tensor veli palatini), muscles of the pharynx (except m. stylopharyngeus) and the mucous membrane in the lower part of the pharynx ``` 4. n. laryngeus superior – contains S, M and PS fibres - level of ganglion inferius - descends along the pharynx and divides into 2 branches: a) r. externus – it contains M fibres and supplies m. cricothyreoideus with a. Thyroidea superior b) r. internus – it contains S and PS fibres - descends along membrana thyreohyoidea, pierces it and supplies the mucous membrane of the larynx from the aditus laryngis to the true vocal folds, mucous membrane of vallecula epiglottica and recessus piriformis (SVA give taste sensation from vallecula epiglottica *taste pathway 5. rr. cardiaci cervicales superiores 6. rr. cardiaci cervicales inferiores - the last two groups contain S and PS fibres, descend along arteria carotis communis and with sympathetic fibers of truncus sympathicus form plexus cardiacus for the heart 7. n. laryngeus recurrens contains S, M and PS fibres, arises in the thoracic cavity. - n. laryngeus recurrens dexter arise at the level of arteria subclavia, but n. laryngeus recurrens sinister arise below arcus aortae. Both nerves ascends to the larynx behind the thyroid gland and between the trachea and the oesophagus - supplies the mucous membrane of the larynx from the true vocal folds to the trachea - supplies together with the accessory nerve muscles of the larynx (except musculus cricothyreoideus), glandula thyroidea and glandula parathyroidea - gives off side branches: a) rr. tracheales - contain s and PS fibres to supply mucous membrane, glands and smooth muscular tissue of the trachea b) rr. oesophagei - contain M, S and PS fibres - supply the upper third of the oesophagus – the mucous membrane, glands and striated muscular tissue 8. rr. cardiaci thoracici – contain S and PS fibres for the heart 9. rr. bronchiales – pass along radix pulmonalis to the lung and form plexus pulmonalis - supplies the mucous membrane, glands and smooth muscular tissue of the bronchi and lungs and also the visceral pleura

Answer 15

1. n. petrosus major contains preganglionic PS fibres; it leaves canalis facialis through hiatus canalis nervi petrosi majoris, enters the middle cranial fossa, pierces cartilage of foramen lacerum and then through canalis pterygoideus reaches fossa pterygopalatina - forms PS root for the PS ganglion – ganglion pterygopalatinum 2. chorda tympani contains sensory and preganglionic PS fibres - leaves canalis facialis through canaliculus chordae tympani - passes through the tympanic cavity, lies b. malleus and incus, then through fissura petrotympanica leaves the cavity - Further travels together with n. lingualis - -> Sensory fibres (SVA) continue to the tongue to supply papillae fungiformes et papillae foliatae and give taste sensation from anterior 2/3 of the tongue * taste pathway - Preganglionic ps fibres run to the PS ganglion – ganglion submandibulare and form the PS root for the ganglion

Answer 16

ganglions of the head (sympathetic parts) lies below basis cranii at the level of C2 - C3; it has: 1. rr. vasulares – supply vessels of head and neck; the main important of them are: a. n. caroticus internus – forms plexus caroticus internus; structures of the plexus: i. fibres along a. ophthalmica form radix sympathica ganglii ciliares - -> supply m. dilatator pupillae ii. n. petrosus profundus – forms radix sympathica ganglii pterygopalatini - -> supplies glandulae nasales and glandulae palatinae iii. nn. caroticotympanici,run to plexus tympanicus - -> supply cavitas tympani, tuba auditiva, cellulae mastoideae b. nn. carotici externi – form plexus caroticus externus, some sympathetic fibres form i. radix sympathica ganglii otici ii. radix sympathica ganglii submandibularis c. n. jugularis 2. rr. viscerales a. rr. laryngopharyngei b. n. cardiacus cervicalis superior descends to form plexus cardiacus

Answer 17

n. phrenicus sympathetic part Ganglion cervicale medium lies C5 - C6; gives off: 1. rr. vasculares: a. n. subclavius 2. rr. viscerales a. rr. thyroidei b. rr. parathyroidei c. n. cardiacus cervicalis medius – it descends to form plexus cardiacus Ganglion cervicale inferius - Sometimes fuses with the ganglia thorcica superiusto form ganglion cervicothoracicum s. ganglion stellatum - Lies C8 – Th1 - Interganglionic fibres b. this and the previous ganglion surround a. subclavia to form ansa subclavia. 1. rami vasulares: a. plexus subclavius b. n. vertebralis forms plexus vertebralis 2. rami viscerales: a. n. cardiacus cervicalis inferior forms plexus cardiacus

Answer 18

``` bulbus olfactorius chiasma opticus ganglion trigeminale ganglion spirale ganglion vestibulare ganglion superius (CN9-10) ganglion inferius (CN9) ``` 1. Ganglion geniculi (n. intermedius), at 90’ curve 2. Ganglion cochleare (n. cochlearis), in cochlea 3. Ganglion vestibulare (n. vestibularis), in meatus acusticus internus 4. Ganglion superius (CN9-10), above foramen jugulare 5. Ganglion inferius (CN9-10), below foramen jugulare

Answer 19

Ganglion ciliare sensory root - radix sensoria ganglii ciliaris of nervus nasociliaris (CN5) - innervate the fibrous (sclera) and vascular (choroid) coats of the eyeball Ganglion pterygopalatinum sensory root - formed by radix sensoria ganglii pterygopalatini of n. maxillaris (CN5) - innervate the mucosa of palate, nasal cavity and nasopharynx Ganglion submandibulare sensory root - formed by radix sensoria ganglii submandibularris of n. lingualis (CN5) - gives off branches that supply sublingual and submandibular glands Ganglion oticum sensory root - formed by radix sensoria ganglii otici of n. mandibularis (CN5) - -> gives off branches that join n. auriculotemporalis (r. parotidei) to supply the parotid gland - There are more branches from the otic ganglion that supply also mucosa of the cheeks, the lips, the fauces and the root of the tongue.

Answer 20

Ganglion ciliare parasympathetic root - nucleus accessorius nervi oculomotorii - fissura orbitalis superior in content of CN3 - via r. inferior n. oculomotorii - supply m. sphincter pupillae and m. ciliaris Ganglion pterygopalatinum parasympathetic root - arise in nucleus salivatorius superior - n. petrosus major (CN 7) and through canalis pterygoideus --> some become n.zygomaticus - > join n.lacrimalis - supply glandulae palatinae, glandulae nasales, glands of nasopharynx and glandula lacrimalis; - Some of the postganglionic PS fibres become components of n. zygomaticus Ganglion submandibulare parasympathetic root - arise in nucleus salivatorius superior - travel within chorda tympani (CN7) - > enter cavitas tympani - > leave it via fissura petrotympanica - -> fossa infratemporalis join to n. lingualis - -> reach the ganglion to synapse with the PS cells Ganglion oticum parasympathetic root - arise in nucleus salivatorius inferiorior - n. tympanicus --> n. petrosus minor (CN9)

Answer 21

``` Ganglion ciliare sympathetic root --> ganglion cervicale superius - n. caroticus internus -> along the BV enter the orbit - innervate m. dilatator pupillae and the smooth muscles of blood vessels ``` Ganglion pterygopalatinum sympathetic root - ganglion cervicale superius - via n. caroticus internus along the BV - > through canalis pterygoideus as n. petrosus profundus - n. petrosus major and n. petrosus profundus within the pterygoid canal form n. canalis pterygoidei - innervate smooth muscles of the BV The PS fibres (n. petrosus major/zygomaticus) and sympathetic fibres (n. petrosus profundus) enter branches of the maxillary nerve (below) and reach along them mucosa of the palate, mucosa of the nasal cavity, mucosa of the nasopharynx – n. palatinus major; descends in canalis palatinus major and through foramen palatinum majus enters oral cavity to supply mucosa of palatum durum and glandulae palatinae --> arise rr. nasales posteriores inferiores to mucosa of nasal cavity – nn. palatini minores - descend in foramina palatina minora, reach the soft palate, innervate it and mucosa of tonsilla palatina - rr. nasales posteriores superiores laterales et rami nasales posteriores superiores mediales from fossa pterygopalatina through foramen sphenopalatinum enter the nasal cavity to supply it. The largest of the nasal branches is – n. nasopalatinus; it runs obliquely downward and forward along septum nasi and then through canalis incisivus enters the oral cavity to supply anterior part of the hard palate • n. pharyngeus – a small branch, arising from the posterior part of the pterygopalatine ganglion; it passes backward and is distributed to mucosa of the nasopharynx, behind the auditory tube Ganglion submandibulare sympathetic root - ganglion cervicale superius - > via n. carotici externi along a. facialis Ganglion oticum sympathetic root - > ganglion cervicale superius - via n. carotici externi along a. meningea media go through

Answer 22

n. infraorbitalis n. zygomaticus fossa pterygopalatina --> fossa infratemporalis

Cranial nerves Flashcards

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