Cranial Nerve Review

Question 1

Contents in Anterior Cranial Fossa

Answer 1

Crysta Galli - attachment of falx cerebri
Cribiform Plate of ethmoid - olfactory nerves
Foraeman Caecum - junction of cribiform and frontal bone
Allows passage of emissary vein from nose into sagittal sinus
Posterior and Anterior ethmoidal canals - branches of naso-cilliary nerve and ophthalmic artery

Question 2

Contents in Middle Cranial Fossa

Answer 2

Optic groove- leads to optic canal
Sella turcica-houses pituitary gland
Superior orbital fissure - communicates with orbit
Hiatus for greater and lesser petrosal nerves
Trigeminal impression - home of the trigeminal ganglion, located on the petrous temporal bone
Tegmen tympani (roof of middle ear)

Question 3

Openings in MCF

Answer 3

Superior orbital fissure
Foramen rotundum
Foramen Vesalian (Emissary sphenoidal foramen)
Foramen ovale
Canaliculus innominatus (occasionally transmits lesser petrosal N)
Foramen spinosum

Question 4

Contents in PCF

Answer 4

Foramen magnum - Medulla, spinal root of accessory nerves, vertebral arteries; apical ligament of dens, tectorial membrane of dens

Hypoglossal canal -Hypoglossal N and meningeal a & n

Jugular foramen - inferior petrosal sinus; Glossopharyngeal (CNIX), vagus(CN X) and accessory(CN XI); sigmoid sinus continues as internal jugular vein

Internal acoustic meatus -Vestibulocochlear(CN VIII),Facial (CN VII), Internal auditory A from basilar A

Question 5

Optic canal

Answer 5

Optic nerve & ophthalmic A

Question 6

Superior orbital fissure

Answer 6

Superior ophthalmic vein, Inferior ophthalmic vein

Nerves: lacrimal, frontal, Trochlear (CN IV) Nasociliary, oculomotor (CN III) and abducent (CN VI)

Question 7

Foramen rotundum

Answer 7

Maxillary nr.

Question 8

Foramen ovale

Answer 8

Mandibular N; and lesser petrosal nerve

Question 9

Foramen spinosum

Answer 9

Middle meningeal. A

Question 10

Foramen lacerum

Answer 10

NOTHING passes through but ICA runs in its floor. Covered by a plate of cartilage in life

Question 11

SVA

Answer 11

15(2)7910

GI Tract
Special Senses of Taste & Smell

Question 12

SSA

Answer 12

28

Special sences of vision, hearing and balance

Question 13

GVA

Answer 13

5(1)910

Sensory (pain or reflex sensations) from internal organs, glands and blood vessels

Create referred pain at point of intersection with general somatic afferent

Question 14

GVE

Answer 14

3791011

Part of ANS - Symp or Parasymp

Motor innervation to smooth muscle, cardiac muscle and glands

Question 15

SVE

Answer 15

5791011

Provide motor to muscles of the pharyngeal arches (larynx & pharynx)

Question 16

GSE

Answer 16

345712

Motor Neurons

• Alpha motor - MSK contractions
• Gamma motor - Sense degree of contractions

Cranial nerves have to GSE to ocular muscles and muscles of tongue

Question 17

GSA

Answer 17

910

Sensory for pain, touch, and temperature from surface of body

Muscle, tendon and joint sense in deeper structures

Present in all spinal nerves, dorsal roots associated