Cranial Nerves Flashcards
CN I
Olfactory
CN II
Optic
CN III
Oculomotor
CN IV
Trochlear
CN V
Trigeminal
CNV1,2,3
V1: Ophthalmic
V2: Maxillary
V3: Mandibular
CN VI
Abducens
CN VII
Facial
CN VIII
Vestibulocochlear
CN IX
Glossopharyngeal
CN X
Vagus
CN XI
Accessory
CN XII
Hypoglossal
Which CN come directly off the forebrain?
I and II
Which CN come out through the orbital fissure?
CN III, IV, V1, and VI
CN II comes out through where?
Optic canal
Which CN comes out through the ethmoid bone (cribiform plate)?
CN I
Where does CN V2 come through?
Round foramen-Rostral alar foramen
Which CN comes out through the oval foramen?
CN V3
Where does the Facial and Vestíbulocochlear n exit out through?
Internal acoustic meatus
Which CN are involved in skeletal mm of the eyeball?
3, 4, 6, 12
Which CN is involved in constricting the pupil?
CN III
The skeletal muscles of the tongue are controlled by which CN through GSE fibers?
CN XII
Where does the optic nerve begin?
Optic disk
Where do the axons of the CN I synapse?
Neurons within olfactory bulbs
What binds odorant molecules?
Cilia of the dendrites in olfactory receptor cells
Which type of neurons are olfactory receptor cells?
Bipolar neurons
Which test can be used to determine CN II function?
Menace response
Which movement of the eye is primarily involved with the CN III?
Medial movement and pupillary constriction
Where does the optic nerve begin?
Optic disk
Where are the ganglion cells of CN II located?
Ganglion cell layer of retina
Describe how CN II runs
Enters optic foramen, passes through optical canal and extends through thalamus
What type of innervation is CN II?
Special somatic senses
What type of innervation is CN I?
Chemical senses
Through which innervation does CN III move the eye medially?
General somatic efferent
Pupillary constriction through CN III is what type of innervation?
Parasympathetic (General Visceral Efferent)
The dorsal oblique muscle is innervated by which CN?
CN IV - Trochlear
Lateral deviation and retraction of globe of the eye is innervated by which CN ?
CN VI - Abducens (General somatic efferent)
Parasympathetic GVE innervation of the CN III goes to the sphincter or dilator pupillae?
Sphincter pupillae
Dilator pupillae muscle is innervated through CN III via what type of innervation?
Sympathetic and Post ganglionic
If a dog has an unresponsive left pupil but normal menace responses bilaterally with slight ptosis in L eye and poor adduction, what is the diagnosis?
L Oculomotor N dysfunction with complete GVE (ANS) neural deficit and partial somatic deficit
In development, a nerve is assigned to each ________________________
Pharyngeal arch
The 1st pharyngeal arch is associated with what action and thus which nerve?
Mastication (CN V3)
Facial expression/CN VII is associated with what pharyngeal arch?
2
Which nerves are associated with pharyngeal arches 1-4?
Lingual (CNV3, CN VII, CN ΙΧ, CN XII)
The larynx and CN X is associated with which arch?
Pharyngeal arch 6
What are the 3 components of CN V?
1- ophthalmic
2- mandibular
3- maxillary
Which CNV components are sensory strictly?
V1 and V2
Which CN V has both sensory and motor components?
CN V3
CN V1 innervates which areas?
Eyes/eyelids/scalp/forehead/horn
The maxillary nerve goes through which fissure ?
Round foramen, alar canal, Rostral alar foramen
Sensory innervation to nasal mucosa, upper teeth, gum, lip, nose is via the CN V__
2
Which CN V division goes through oval foramen?
CN V3
What is innervated sensory by the CN V3?
Ear/face/ cheek/ tongue/lower teeth/gum/lip (Buccal, Lingual, inf alveolar, Mental Rostral/caudal, auriculotemporal - BLIMA)
The motor component of CN V3 innervates ?
The Muscles of mastication
Describe paralysis of the Mandibular N
Temporalis/Masseter mm wasting, prominent zygomatic arch
Which test is used to determine Facial Nerve function (along with CNV 1,2)
Palpebral reflex and Vibrissae response (touching upper lip)
If there is injury to to one or more branches of CN VII, what is a possible clinical sign?
Neuropraxia
The CN VIII leaves the petrous temporal bone via the _____________________.
Internal Acoustic Meatus
The minor petrosal nerve is part of which CN?
IX
Is the minor petrosal nerve parasympathetic and sympathetic?
Parasympathetic
To which ganglion does the minor petrosal nerve carry PSNS fibers?
Otic ganglion
true or false: CN X is sympathetic?
False, it is parasympathetic
Define the pharyngeal reflex
gag reflex - throat contraction that happens when something touches the roof of the mouth, back of the tongue/throat or the areas around the tonsils
Which nerve along with CN X innervates the larynx and pharynx?
CN XI - Accessory
Which root of CN XI innervate trapezius and sternocephalicus muscle?
Spinal root
- dorsal : trapezius
- ventral : sternocephalicus
The sole motor supply to the intrinsic and extrinsic muscles of the tongue is CN _____.
CN 12
