Skull and meninges Flashcards
Which structures pass through the superior orbital fissure?
Trochlear n. Abducens n. Occulomotor n. Ophthalmic branch of trigeminal n.
Which structures pass through the optic canal?
Optic nerve and ophthalmic artery
Which structure passes through foramen rotundum?
Maxillary branch of trigeminal nerve
Which structure passes through foramen ovale?
Mandibular branch of trigeminal nerve
Which skull foramen does the optic nerve pass through?
Optic canal
Which skull foramen does the trochlear nerve pass through?
Superior orbital fissure
Which skull foramen does the abducens nerve pass through?
Superior orbital fissure
Which skull foramen does the occulomotor nerve pass through?
Superior orbital fissure
Which skull foramen does the ophthalmic branch of the trigeminal nerve pass through?
Superior orbital fissure
Which skull foramen does the maxillary branch of the trigeminal nerve pass through?
Foramen rotundum
Which skull foramen does the mandibular branch of the trigeminal nerve pass through?
Foramen ovale
Which skull foramen does the middle meningeal artery pass through?
Foramen spinosum
What passes through the foramen spinosum?
Middle meningeal artery
What passes through the jugular foramen?
Glossopharyngeal, vagus and spinal accessory nerves
What passes through the foramen magnum?
Medulla oblongata, vertebral arteries, spinal accessory nerve,
What Sx will a lesion of the olfactory nerve cause?
Ipsilateral anosmia
Which hemiretina decussates?
Nasal
Which hemiretina remains ipsilateral?
Temporal
A lesion of the right optic nerve will cause what problem with the pupillary light reflex?
Bilateral loss of reflex to light shined in ipsilateral eye. No change to reflex when light shined in contralateral eye.
A lesion of the right occulomotor nerve will cause what problem with the pupillary light reflex?
Loss of pupillary reflex of ipsilateral eye to light shined in either eye
Name 5 signs of a lesion to the occulomotor nerve?
Ipsilateral ptosis, lateral strabismus, dilated pupil (mydriasis), fixed pupil (loss of papillary reflex), diplopiadouble vision
Define mydriasis
Dilated pupil
How do we say ‘dilated pupil’?
Mydriasis
Define miosis
Constricted pupil
How do we say ‘constricted pupil’?
Miosis
Which muscles does the occulomotor nerve supply?
Superior, inferior and medial rectus, inferior oblique and superior levator palpebrae
Which nuclei are associated with the occulomotor nerve?
Occulomotor nuc and Edinger-Westphall nuc.
At what level of the brainstem is the trochlear nucleus?
Inferior colliculus
Which muscle does the trochlear nerve supply?
Superior oblique
What movement of the eye does the trochlear nerve cause?
Depression of the eye when adducted
What type of strabismus will a lesion of the trochelar nerve cause?
Supero-medial
How may a person with a trochlear lesion compensate?
Tilt head to contralateral shoulder
Which nuclei are associated with the trigeminal nerve?
Spinal trigeminal nucleus. Chief/principal sensory nucleus. Mesencephalic motor nucleus. Trigeminal motor nucleus.
What symptoms will a lesion of the trigeminal nerve cause?
Loss of touch, pain and temperature from face. Pain or parasthesia from ipsilateral face. Loss of blink reflex. Flaccid paralysis of muscles of mastication.
Which regions does the principal sensory nucleus receive input from?
DCFNOS
Dura, cornea, face, nasal cavity, oral cavity, scalp
What type of deficit will a lesion of the abducens cause?
Medial strabismus
What Sx will a lesion of the facial nerve cause?
Facial paralysis. Loss of blink reflex. Loss of taste. Dry mouth. Loss of lacrimation. Noises sound louder on ipsilateral side.
What is the course of the facial nerve through the skull?
Exits through internal acoustic meatus and leaves through stylomastoid foramen
Which nuclei are associated with the facial nerve?
Solitary nucleus. Spinal trigeminal nucleus. Facial motor nucleus.
What part of the body does the facial nerve convey pressure, pain and temperature?
Ipsilateral external ear
Which nuclei are associated with the glossopharyngeal nerve?
Nucleus ambiguus. Solitary nucleus. Spinal trigeminal nucleus.
What Sx would be caused by a lesion of the glossopharyngeal nerve?
Loss of gag reflex. Loss of taste from posterior 1/3 of tongue. Uvula deviates to contralesional side. Dysphagia
What nuclei are associated with the vagus nerve?
Nucleus ambiguus. Solitary nucleus. Spinal trigeminal nucleus. Dorsal motor nucleus of vagus.
Which nuclei are associated with the spinal accessory nerve?
Spinal accessory nucleus
Which muscles are innervated by the spinal accessory nerve?
Sternomastoid and trapezius
What is a Sx of hypoglossal nerve palsy?
When deviated, tongue deviates to ipsilesional side. Ipsilesional wasting/atrophy.
Which nerves are associated with the nucleus ambiguus?
9 and 10
Which nerves are associated with the solitary nucleus?
7, 9 and 10
Which nerves are associated with the spinal trigeminal nucleus?
5, 7, 9 and 10
A lesion of facial corticobulbar fibres will cause what kind of facial weakness?
Lower face only (ie forehead spared)
A lesion of the facial nucleus or nerve will cause what kind of facial weakness?
Upper and lower face (ie forehead affected)
Facial weakness of the entire face implies what level of lesion?
Facial nucleus or nerve
Facial weakness of the lower face with sparing of the forehead implies what level of lesion?
Cortical or corticobulbar
What are the 5 layers of the scalp?
SCALP
Skin. Connective tissue. Aponeurosis. Loose connective tissue. Periosteum.
What are the 2 layers of dura mater?
The endosteum of the skull vault and the true meningeal layer of dura
What is the middle layer of the skull called?
Diploe
What are the 3 layers of the skull?
Internal plate, diploe, external plate
Which 4 bones form the pterion?
Frontal, parietal, greater wing of sphenoid, squamous temporal bone
What is the line of demarcation between the two parts of the frontal bone?
Supraorbital margin
What is the name of the dural reflection that covers sella turcica?
Diaphragma sella
How many mls of CSF are there in the brain?
150ml
How is cerebral perfusion pressure calculated?
MAP - ICP
