Cranial Nerves (VII-XII) PDF

CRANIAL NERVES (VII-XII) Prof. Dr. Selda Önderoğlu Faculty of Medicine Department of Anatomy FACIAL NERVE (CN VII) Facial n.(CNVII) Contain FIBERS: Motor, Sensory (taste+general sensation-skin), parasymp. NUCLEI: all at PONS level Motor Nucleus (motor) Solitary tract Nucleus...

CRANIAL NERVES (VII-XII) Prof. Dr. Selda Önderoğlu Faculty of Medicine Department of Anatomy FACIAL NERVE (CN VII) Facial n.(CNVII) Contain FIBERS: Motor, Sensory (taste+general sensation-skin), parasymp. NUCLEI: all at PONS level Motor Nucleus (motor) Solitary tract Nucleus (taste+gen.sensation) superior salivatory Nucleus(psymp.) CN VII Leaves brain stem from: pontobulbar Sulcus Motor fibers of VII innervate: Mm of expression Stapedius m. (middle ear) Stylohyoid m. (neck) Post. Belly of Motor nucleus is Digastric m.(neck) located at lower pons  Solitary Tract Nucleus (taste+general Sensation) Located at pons(upper part of solitary tract nucl) Intermediate n. (taste, general sensation (pain,heat etc.) Cell body is at the:Genicular Ganglion carriesTaste sensation (from anterior 2/3 of tongue, soft palate) intermediate n. is the name of the sensory part of facial n.  Superior Salivatory Nucleus At Pons Psymp. Nucleus of VII innervate: Sublingual gland Submandibular Gland Lacrimal Gland Nasal Glands Small salivary glands in mouth Course of Facial n. and Intermediate n Pontobulbar Sulcus internal acustic Meatus Facial Canal (in temporal bone) Genu, genicular ganglion Brs in canal: greater petrosal N+ n. to Stapedius m + chorda tympani CN VII:Exit from skull:from Stylomastoid Foramen Brs after exit: posterior auricular n. Digastric branch,stylohyoid br Enters Parotid Gland :brs in Genicular ganglion: gland:temporal, zygomatic, sensory gang of facial n. buccal, mandibular, cervical  Branches of Facial N. (in Facial Canal ) greater petrosal n. N. To stapedius Chorda tympani Greater Petrosal nerve N. Of pterygoid canal Pterygopalatine Ganglion Innervates: Lacrimal Gland Nasal Glands Small Salivary Glands  Chorda Tympani(taste+psymp.) Courses within lingual n. Carries taste from ant. 2/3 of tongue Genicular gang. intermediate n. Solitary tract&nucl. Psymp:preganglionic psymp. submandibular ganglion Postsynaptic fibers innervate submandibular&Sublingual glands Brs of Facial N(after its exit from Stylomastoid Foramen) posterior auricular (occipital br, auricular br) Digastric br, stylohyoid br Temporal brs, Zygomatıc brs, buccal brs, marginal mandibular br, cervical br ( remember: these nn.branch in the parotid gland)  central facial paralysis Seen in supranuclear levels of facial n. The signs are seen:Below the level of the eye, on the contralateral side Paresis especially in perioral muscles The mouth is pulled to the healthy side Why contralateral?  facial nerve damage (Bell’s Palsy) The result in the patient is different according to the place of the damage. Example: At its exit from brainstem 1-paralysis of the mm. Of expression on the lesion side(lower motor neuron type), 2-hyperacusis, 3-loss of cornea reflex, 4-function of lacrimal& salivary glands impaired, 5-loss of taste sensation on the ant. 2/3 of tongue BELL’S PALSY(damage to CNVII in facial canal) psymp taste VESTIBULOCOCHLEAR NERVE (SPECIAL SENSORY)  SSA Vestibular n. (balance) Cochlear n. (hearing) Exit from brain stem:Pontobulbar sulcus Course: temporal bone  cochlear nerve (hearing) Begins from:Organ of Corti Spiral Ganglion (Located in the inner ear) Cochlear n Reaches the nuclei (at pons) ant. Cochlear Nucl. post. cochlear Nucl.  Vestibular nerve (balance) inner ear Semicircular Ducts , utricule, saccule Vestibular Ganglion Vestibular N. Vestibular Nuclei(4 in no) passThrough:inf. Cerebellar peduncle Reach:Cerebellum Vestibular Nerve (balance) GLOSSOPHARYNGEAL NERVE (CN IX)  GLOSSOPHARYNGEAL NERVE Fibers: Sensory+motor+psymp. Nuclei: Nucleus ambiguus(motor) inf. Salivatory Nucleus(psymp.) solitary tract Nucleus(taste) Exit br.stem: from retrooliv. Sulcus Leaves skull: jugular Foramen Has 2 sensory ganglia: superior Gang. +Inferior Gang. SENSORY GANGLIA of glossopharyngeal n.  Types of Fibers of glossopharyngeal nerve General sensory (post.1/3 part of tongue, soft palate, pharynx, tonsils) taste (from post 1/3 of tongue) General Sensory (post part of concha of auricle) Motor (stylopharyngeus m) psymp (parotid gland)  Psymp. fibers of cr 9 Tympanic plexus Inf. Salivatory nucl. Tympanic n Tympanic Plexus Lesser (superficial) inf.saliv.nuc l petrosal n Otic Gang. Auriculatemporal N. Parotid gland  Other brs. Of 9 Pharyngeal brs. Br. To Stylopharyngeus m. Br. To carotid sinus(sinus n.) Tonsillar brs. Lingual brs. Fiber types of 9 VAGUS NERVE (CN X ) Fibers types: Vagus nerve Sensory,motor,psymp Nuclei: Nucleus ambiguus Dorsal Nucleus of vagus solitary tract Nucleus Exit from brain stem:Retroolivary Sulcus Exit from skull: Jugular Foramen Has 2 sensory ganglia: superior Gang. +inferior gang.  Course and branches of CN X in the neck region in the neck: courses Bw.int carotid a., int. Jugular v. Branches that exit inferior to sup. Gang. Meningeal br. Auricular br. ınferior to inferior Gang. Pharyngeal br. superior laryngeal n. Cervical cardiac brs.(sup., inf.) recurrent laryngeal n. Branches of X In thorax and abdomen Pulmonary Plexus, Oesophageal plexus, ant. Vagal trunk post. Vagal trunk ant, post. Gastric brs Hepatic brs Coeliac brs Renal brs So up to left colic flexure  Fiber types of CN X Psymp. (dorsal motor nucl. of vagus) inn. organs up to left colic flexure motor (nuc. ambiguus) pharynx, larynx, mm of soft palate (except tensor veli palatini & stylopharyngeus mm) Sensory-taste (solitary nucl. tract) (Region around epiglottis)  General sensation : -from pharynx, larynx, soft palate, concha of auricle - reaches to solitary tract and nucl. After solitary tract:general sensation fibers reach trigeminal Nucleus  ACCESSORY NERVE (CN XI) has only motor fibers -Has 2parts: cranial+spinal Fibers:only Motor Nuclei: cranial root (nuc. ambiguus) spinal root (spinal nucl.of accessory n.- upper 6 cervical segments of spin. cord)-courses up&enters skull through for.magnum -in the skull:Two roots unite Form a trunk Leave skull from:Jugular foramen İnn. Stclmastoid+trapezius mm. HYPOGLOSSAL NERVE (CN XII)  Fibers: only motor( innervate mm. Of tongue) Nucleus: Nucleus of hypoglossal (medulla oblongata) Anterolateral Sulcus hypoglossal canal Innervates tongue mm. +gives a br. To Ansa cervicalis (descending br. Of hypoglossal n) Ansa cervicalis Thank you for your patience!!