Cranial Nerves I-VI PDF

CRANIAL NERVES 1, II, O, IV, T, VI Prof Dr MT CRANIAL NERVE MODALITIES Olfactory n-SSA Optic n-SSA Oculomotor n-GSE, GVE Trochlear n-GSE Trigeminal n-GSA, SVE Abducent n-GSE Facial n-GSA, GVE, SVA, SVE Vestibulocochlear n-SSA Glossopharyngeal n-GSA, GVE, GVA, SVA, SVE Vagus n-GSA, GVA, GVE, S...

CRANIAL NERVES 1, II, O, IV, T, VI Prof Dr MT CRANIAL NERVE MODALITIES Olfactory n-SSA Optic n-SSA Oculomotor n-GSE, GVE Trochlear n-GSE Trigeminal n-GSA, SVE Abducent n-GSE Facial n-GSA, GVE, SVA, SVE Vestibulocochlear n-SSA Glossopharyngeal n-GSA, GVE, GVA, SVA, SVE Vagus n-GSA, GVA, GVE, SVE Accessory n-SVE SSA:special somatic afferent Hypoglossus n-GSE SVA:special visceral afferent SVE:special visceral efferent (motor fibers to branchial muscles) GSA:general somatic afferent GVA:general visceral afferent GVE:general visceral efferent GSE:general somatic efferent CRANIAL NERVE I Olfactory Nerve Olfaction SSA In the mucous membrane of the nasal cavity; sup nasal concha and the adjacent part of the nasal septum Olfactory nerves Olfactory bulb Olfactory tract Lateral olfactory stria —primary olfactory tract Medial olfactory stria Anterior commissure —contralateral olfactory structures  Olfactory nerves Efferent fibers from the opposite side (to the Olfactory bulb inner nuclear cells; these Olfactory tract cells are excited by the mitral cells while inhibited by the tufted Lateral olfactory stria cells) —primary olfactory tract Medial olfactory stria Anterior commissure —contralateral olfactory structures !"#$%&'(&)%*+(,-'+,%*+  Mitral and tufted cells (2nd order neurons) Primary olfactory bipolar neurons (1st order neurons) Brodmann 28 & Primary olfactory cortex (entorhinal area) CRANIAL NERVE II Optic Nerve Vision SSA Optic nerve (SSA) Ganglionic layer of retina (innermost layer)>converge on the optic disc. 4cm long directed backwards and medially through the optic canal>cranial cavity>optic chiasma Lateral geniculate body (receives fibers only from the opposite sides of the visual fields) Calcarine sulcus (primary visual cortex) (Area 17, secondary visual area 18, 19) CRANIAL NERVE III Oculomotor Nerve Eye movements Eye reflexes (pupilla, lens reflexes+accommodation convergence) GSE, GVE Motor fibers to all of the extrinsic eye mm except the sup oblique and rectus lateralis muscles PS fibers to sphinchter pupilla and ciliaris muscles ( through the ciliary ganglion) Oculomotor n. Originating from the midbrain; innervates the sup, inf, med rectus mm, inf oblique and levator palpebrae mm In the interpeduncular fossa the nerve is between the posterior cerebral and superior cerebellar arteries.  Lacrimal Near the sup. orbital fissure it divides into Frontal superior and inferior divisions. Trochlear Oculomotor-sup Abducens Oculomotor-inf Superior division-GSE: innervates all extrinsic muscles of eye except the superior oblique and lateral rectus mm LR6 SO4 REST3 Inferior division-GVE Edinger-Westphal Nucleus preganganglionic fibers>ciliary ganglion postganglionic /postsynaptic fibers>short ciliary nn>constrictor pupillae m of iris and the ciliary m  CRANIAL NERVE IV Trochlear Nerve Eye Movement GSE Vertical Diplopia Vertical Diplopia Controls eyeball movement-turns it downwards and laterally CRANIAL NERVE V Trigeminal Nerve Ophthalmic Nerve (V1): GSA (eyeball, lacrimal gl, conjunctiva, nasal mucosa, skin of nose, eyelids, skin of forehead, scalp) Maxillary Nerve (V2): GSA (lower eyelid, nasal cavity, nasal alar skin, teeth and gums of maxilla, skin and mucous membranes of cheek and upper lip) Mandibular Nerve (V3): GSA + SVE (teeth and gums of the mandibula, skin of temporal region, part of auricle, lower lip, lower part of face, and muscles for biting, chewing, and swallowing)  Trigeminal nerve (GSA+SVE) § Spinal tract&spinal nucleus (medulla oblongata) § Principal sensory nucleus (pons) § Mesencephalic nucleus (mesencephalon) § Motor nucleus (pons) Branches of CNV Ophthalmic n (superior orbital fissure) Maxillary n (foramen rotundum) Mandibular n (foramen ovale)  V1 Sensory branches to the V2 face and scalp V3 Ophthalmic n (GSA, GVE) 1- Frontal n (GSA) supraorbital n supratrochlear n 2- Lacrimal n (GSA) 3- Nasociliary n (GSA) long ciliary n (GSA+GVE) GVE fibers: Sympathetic fibers from the sup cervical gang. to dilator pupilla mm (just giving a ride, not functionally involved) posterior ethmoidal n anterior ethmoidal n infratrochlear n  Maxillary n (GSA) (named as infraorbital n as it enters the infraorbital canal) Meningeal br (in the cranium) Ganglionic br (ptplf) Zygomatic n (ptplf) (ps fibers- ptp ganglion- to the lacrimal gl) Posterior superior alveolar n (ptplf) Superior Middle superior alveolar n (ioc) alveolar nn Anterior superior alveolar n (ioc) Palpebral (on the face) Nasal (on the face) Superior labial (on the face) Mandibular n (GSA, SVE) Meningeal br Anterior trunk: Nn to mastication mm Buccal n Posterior trunk: Auriculotemporal n Lingual n Inferior alveolar n Parasympathetic fibers transported by V2 and V3 Pterygopalatine Ganglion Functionally connected with the facial n and closely related to the maxillary n (topographically) Postganglionic fibers are carried with the zygomatic branch of the maxillary n to supply secretomotor fibers to the lacrimal gland Otic Ganglion is topographically related to the mandibular n, but functionally related to the glossopharyngeal n Preganglionic fibers carried by tympanic branch of the tympanic plexus and the lesser petrosal n (from the CN IX-glossopharyngeal n) and the postganglionic fibers pass to the auriculotemporal n to reach the parotid gland (secretomotor fibers) CRANIAL NERVE VI Abducens Nerve Lateral Eye Movements GSE *Location of the structures passing through the cavernous sinus WHICH OF THE CNs DOES NOT STOP BY THE THALAMIC NUCLEI? Which nerve damages cause symptoms appeared in the square heads? You can do it! Can you figure how the partial and total blindness (showed in the visual fields-filled with red lines) is possible resulted due to the lesions labeled at the A,B,C,and D locations to the optic nerve? Dropped eyelid: which nerve damage can cause it?..when I said cavernous sinus..and structures passing through it… Name the names! Nu t in a she ll !