Cranial Nerve Examination Flashcards
Describe the route which the olfactory nerve takes from the olfactory cells to the brain?
Olfactory cells of the nasal mucosa then the olfactory bulbs and then travels to the pyriform cortex
What structures/signs should be examined when testing the optic nerve?
Opthalmoscope Pupillary responses Visual acuity Visual field Blind spot
Where is the nucleus of the oculomotor nerve?
Motor nucleus is the oculomotor nucleus in the midbrain
Parasympathetic nucleus is the edinger-westphal nucleus in the midbrain
Which muscles do the oculomotor nerve innervate?
Inferior oblique
Superior rectus
Medial rectus
Inferior rectus muscles
Where is the nucleus of the trochlear nerve?
Inferior colliculus of the midbrain
Which muscle is innervated by the trochlear nerve?
Superior oblique muscle
Which cranial nerve has the longest intracranial course?
Trochlear nerve
Which muscle is innervated by the abducens nerve?
Lateral rectus muscle
What is the internuclear ophthalmoplegia?
A disorder of conjugate gaze where there is failure of adduction of the affected eye with nystagmus on lateral gaze in the contralateral eye.
What conditions is. highly associated with internuclear ophthalmoplegia?
MS
What are the signs/symptoms of Horner’s syndrome?
Mitosis
Ptosis
Anhidrosis
Apparent enopthalmos
What are the possible causes. of Horner’s. syndrome?
Congenital Brainstem stroke Cluster ehadache Apical lung tumour MS Carotid artery dissection Cervical rib fracture Syringomyelia
What are the functions of the trigeminal nerve?
Sensory input from the face and anterior 2/3 of the tongue
Innervates muscles of mastication
Where are the nuclei of the trigeminal nerve situated?
Sensory nuclei in pons and medulla
Motor nuclei in pons
How is herpes zoster opthalmosis treated?
Oral acyclovir
What is the function of the facial nerve?
Innervates muscles of facial expression
Provides sensation of the anterior 2/3 of the tongue
Innervates the salivary glands
Where are the nuclei of the facial nerve situated?
Motor nuclei in pons
sensory and parasympathetic nuclei in the medulla
Which nerves are involved in the corneal reflex?
Afferent CN5
Efferent CN7
What are the functions of the glossopharyngeal nerve?
Sensation of posterior 1/3 of tongue, pharyngeal wall
Carotid sinus blood pressure receptors
Swallowing and gag reflex
Innervates parotid glands
What are the functions of the vagus nerve?
Chemoreceptors in carotid bodies
Pain receptors in respiratory and digestive tracts
Sensation of external. ear, larynx and pharynx
Controls heart rate and stroke volume, smooth muscles of the digestive tract and bronchial tubes, swallowing
What is the function of spinal accessory nerve?
Innervates sternocleidomastoid and trapzieus muscles
What is the function of hypoglossal nerve?
Innervates the tongue to control speech and swallowing
If there is a lesion fo CN 3, 4, 5 (1+2), and 6, which structure is likely the location of the lesion?
Cavernous sinus
If there is a lesion fo CN 3, 4, 5(1), and 6, which structure is likely the location of the lesion?
Superior orbital fissure
