Question

For each of the cranial nerves create a Table/Chart showing: 1. cranial nerve number 2 cranial nerve name 3  type: motor/sensory/mixed 4. name/location of cranial nerve nucleus (-ei) 5. function(s) 6. possible clinical consequences of a unilateral lesion of the left cranial nerve 7. topographical landmark on the brain surface that allows you to identify that specific cranial nerve

Answer 1

Cranial nerve : 12 pairs nerves that emerge directly from brain and relay information between brain and other body parts. the cranial nerves are considered as peripheral nervous system (nervous system which consists of nerves and ganglion outside the brain )

number of cranial nerve	name of cranial nerve	type	name/location of cranial nerve nuclei	functions	clinical consequence of unilateral lesion of left nerve	topographical landmark on brain to identify
i	olfactory	sensory	olfactory bulb	identify smells	reduced smell and taste sensation	olfactory bulb is the topographical landmark of olfactory nerve on brain
ii	optic	sensory	lateral geniculate nucleus	vision or eye sight	visual field defects,visual losses ,blindness,(mainly left eye)	supirior colliculus( lying roof of midbrain )and lateral geniculate nucleus of thalamus(part of mid brain) the topographical landmark of optic nerve
iii	oculomotor	motor	edinger westphal nuclei of midbrain	it is' eye mover'.it moves eyeball,eyelid, and adjust the lens,pupil	fixed dilated pupil (mainly left eye)	it enters the orbit via superior orbital fissure. its nucleus located ventral to the cerebral aqueduct and passes between supirior cerebellar artery and posterior cerebral . and it splits into two braches .these are the topographical landmark .
iv	trochlear	motor	nuclei of midbrain	moves eyeball	weakness of downward and inward eye movement (mainly left eye as left unilateral lesion)	have greatest intracranial length and it is the only nerve that exits from dorsal aspect of brainstem .it emerges from caudal mesencephalon ,just bellow inferior colliculus .it runs on the lateral wall of cavernous sinus these are the topographical landmarks.
v	trigeminal	mixed	nucleus of pons	sensory action - all type of sensation of forehead,scalp,upper eyelid,side of nose,teeth motor action-movement of jaw muscle for chewing	reduced sensation over forehead,scalp,eyelid,nose. weakness of jaw movement (mainly left side)	splits into three branches .this is the main landmark to identify trigeminal nerve .trigeminal ganglion located in Meckel's cave is also topographical landmark of these nerve .
vi	abducens	motor	nucleus of pons	maintain the rotation of eyeball	inability to look laterally	these nerves leaves the brainstem at the junction of pons and medulla and enters subarachnoid space .it runs through Dorello's canal.these are the topographical landmark .
vii	facial	mixed	nucleus of pons	sensory action- identify taste motor action- maintain facial expression ,control secretion of tear and saliva chewing,movement of neck,regulate tension on ear ossicle	facial weakness,facial muscle destruction ,problem in secretion of tear and saliva	facial nerve exit skull through stylomastoid foramen it is the landmark . tragal pointer is also a landmark .
viii	auditory or vestibulocochlear	sensory	nucleus of pons	hearing and maintain body equilibrium	unilateral sensorineural deafness (mainly left as left unilateral lesion occurs )	it runs between the base of pons and medula oblongata .cerebellopontine angel is the topographical landmark of these nerve .
ix	glossopharyngeal	mixed	nuceus of medulla	sensory action- identify taste and touch on tongue,soft palate, monitors blood pressure,level of O2, CO2 motor action- control the movement of tongue,pharynx helps in swallowing	unilateral lessions do not affect usually .bilateral lession affects .	possessing sheath of dura mater .passes beneath the styloid process and exits the brainstem out from the side of upper medulla just anterior to vagus nerve these are the topographical landmark .
x	vagus	nixed	spinal accessory nucleus of medulla	movement of muscle of vocal cord lungs, controls respiratory reflexes, peristaltic movements, stimulate voluntary muscle to control speech,swallowing,coughing secretion of gastric gland and slow down of heart beat	unilateral nerve lesion is very rare. palatal weakness,nasal speech ,nasal regurgitation of food i.e bringing swallowed food up again through nose	passes between internal jugular vein and internal carotid artery ,passes through jugular foramen,part of carotid sheath . nodose sensory ganglion ,jugular ganglion are the topographical landmark of vagus nerve.
xi	accessory (spinal aceessory)	motor	medulla	movement of muscles of pharynx larynx, vocal cord , governs movement of neck,shoulder,head also helps in swallowing	weakness of muscles of pharynx,larynx,vocal cord,shoulder,neck	originate from the junction of medula oblongata and spinal cord travels through jugular foramen .it is notable for both enter and exit the skull. these are the topographical landmark .
xii	hypoglossal	motor	hypoglossal nucleus of medulla	movement of muscles of tongue,neck helps in swallowing and speech	problem in swallowing ,partial paralysis of tongue .	hypoglossal trigone is the topographical landmark of these nerve on brain .

12 Cranial Nerves olfactory smell optic vision oculomotor eye movement and pupil reflex trochlear eye movement trigeminal face sensation and chewing abducens eye movement facial face movement and taste vestibulocochlear hearing and balance glossopharyngeal throat sensation, taste, and swallowing vagus movement, sensation, and abdominal organs accessory neck movement hypoglossal movement, sensation, and abdominal organs