Neurosurgery Flashcards

1
Q

What foramen does the oculomotor nerve pass through?

A

Superior orbital fissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What cranial nerves pass through the jugular foramen?

A

Glossopharyngeal (CN IX)
Vagus (CN X)
Accessory (CN XI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What cranial nerves pass through the internal acoustic meatus?

A

Facial Nerve (CN VII)
Vestibulocochlear Nerve (CN VIII)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What foramen does the middle meningeal artery pass through?

A

Foramen Spinosum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Name the 7 foramina that the cranial nerves pass through?

A

Optic Canal (II)
Superior Orbital Fissure (III, IV, V1, VI)
Foramen Rotundum (V2)
Foramen Ovale (V3)
Internal acoustic meatus (VII, VIII)
Jugular Foramen (IX, X, XI)
Hypoglossal Canal (XII)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name the 4 cranial nerves that pass through the superior orbital fissure?

A

Occulomotor
Trochlear
Trigeminal - ophthalmic branch
Abducens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What foramina are part of the sphenoid bone?

A

Optic canal
Superior Orbital Fissure
Foramen Rotundum
Foramen Ovale
Foramen Spinosum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What sinuses join together to form the internal jugular vein?

A

Inferior Petrosal Sinus and Sigmoid Sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What nerve supplies the stapedius muscle?

A

Facial Nerve (CN VII)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which nerve can be damaged during carotid surgery?

A

Hypoglossal Nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What structures pass through the foramen ovale?

A

O - Otic ganglion
V - V3 (mandibular nerve)
A - Accessory meningeal artery
L - Lesser petrosal nerve
E - Emissary veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What structures pass through the superior orbital fissure?

A

Oculomotor Nerve (CN III)
Trochlear Nerve (CN IV)
Ophthalmic Nerve (CN V1) - Lacrimal, frontal and nasociliary branches
Abducens Nerve (CN VI)
Recurrent Meningeal Artery
Superior Ophthalmic Vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which nerves are at risk of damage during a carotid endarterectomy?

A

Hypoglossal nerve
Greater auricular nerve
Superior laryngeal nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which of the cranial venous sinusus is unpaired?

A

Superior sagittal sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What blood vessel is most commonly ruptured in an extradural haematoma and where does it originate?

A

Middle meningeal artery <- Maxillary artery <- External Carotid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which branches of the external carotid artery are responsible for blood supply to the scalp?

A

Posterior auricular - superior and posterior to ear
Occipital - back of scalp
Superficial temporal arteries - frontal and temporal regions

Also supplied with blood by ophthalmic artery which is the first branch of the internal carotid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Trauma to which part of the scalp causes middle meningeal artery rupture?

A

Pterion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where does the internal carotid artery enter the cranium?

A

Carotid canal in the petrous part of the temporal bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

A lesion of what structure causes a homonymous hemianopia?

A

Optic tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What visual field defect does compression of the optic chiasm result in?

A

Bitemporal hemianopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What visual field defect does a lesion in the parietal lobe result in?

A

Inferior homonymous quadrantaopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What visual field defect does a lesion in the temporal lobe result in?

A

Superior homonymous quadrantaopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Causes of optic chiasm compression

A

Pituitary tumour - compression of the inferior part of the optic chiasm and results in a more significant defect in the superior quadrant

Craniopharyngioma - compression of the superior part of the optic chiasm and results in a more significant defect in the inferior quadrant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What nerve runs very closely to the base of the middle meningeal artery?

A

Auriculotemporal nerve - branch of Mandibular nerve (CN V3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which nerve is most likely to be damaged due to raised ICP?

A

Abducens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which layer is the danger area of the scalp and why?

A

Loose areolar connective tissue - it contains emissary veins. These are valveless veins that connect the extracranial veins with intracranial sinuses and are potential cause for spread of infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which 3 branches of the external carotid artery supply the scalp with blood?

A

Superficial temporal
Posterior auricular
Occipital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What branch of the internal carotid artery supplies the scalp with arterial blood?

A

Supratrochlear and supraorbital branches of the ophthalmic artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the venous drainage of the deep temporal skull?

A

Pterygoid venous plexus

30
Q

Why do scalp lacerations bleed profusely?

A
  • The pull of the occipitofrontalis muscle prevents the closure of the bleeding vessel and surrounding skin.
  • The blood vessels to the scalp are adhered to dense connective tissue, preventing the vasoconstriction that normally occurs in response to damage.
  • The blood supply to the scalp is made up of many anastomoses, which contribute to profuse bleeding.
31
Q

Which cranial nerve provides innervation to the scalp?

A

Trigeminal CN V

32
Q

What causes the pupil to become fixed and dilated following head injury?

A

Increased intracranial pressure - > transtentorial herniation
3rd CN compression

33
Q

What is the surgical procedure to decrease intracranial pressure following head injury?

A

Parieto-temporal craniotomy

34
Q

What type of drug is given in SAH when there is no increase in ICP? and why?

A

CCB - it reduced vasospasm

35
Q

What is the cushings reflex?

A

Physiological response to increased ICP - Hypertension and bradycardia.
It is also associated with wide pulse pressure and irregular breathing.
Hypertension occurs as ICP is greater than MAP so in order to maintain cerebral perfusion, MAP has to increase.

36
Q

What does CN IV do and how does a 4th nerve palsy present?

A

Supplies innervation to superior oblique muscle
Vertical diplopia
Head tilts away from affected side
Unable to look down and medially

37
Q

Which type of intracranial bleed causes sudden loss of consciousness and collapse without traumatic event?

A

SAH

38
Q

How soon after the traumatic event do symptoms need to start in order for the sub dural haemorrhage to be classified as acute?

A

<72 hours

39
Q

Which patient group is most likely to have an intraventricular haemorrhage?

A

Neonates

40
Q

A 28 year old man falls and hits his head against a wall. There is a brief loss of consciousness. When assessed in accident and emergency he is alert and orientated with a GCS of 15, imaging shows no fracture of the skull. What is his risk of having an intracranial haematoma requiring removal?

A

1 in 6000

41
Q

What is a signature fracture?

A

Depressed skull fracture where the impression resembles the source of impact

42
Q

Which nerve accompanies the labyrinthine artery?

A

Facial nerve (CN V) and vesticulocochlear nerve (CN VIII)

43
Q

What artery does the posterior inferior cerebellar artery arise from?

A

Vertebral

44
Q

What are the contents of the cavernous sinus?

A

Occulomotor nerve (III)
Trochlear nerve (IV)
Ophthalmic nerve (V1)
Maxillary nerve (V2)
Carotid artery (internal)
Abducens nerve (VI)

O TOM CAT

45
Q

What are the non-terminal branches of the facial nerve?

A

Intracranial:
Greater petrosal nerve
Nerve to stapedius
Chordatympani
Extracranial:
Posterior auricular nerve
Nerve to digastric
Nerve to sylohyoid

46
Q

What are the branches of the facial nerve that arise within the parotid and what muscles do they innervate?

A

Temporal - frontalis, orbicularis oculi and corrugator supercilii
Zygomatic - orbicularis oculi
Buccal - orbicularis oris,levator anguli oris, buccinator and zygomaticus
Mandibular - depressor labii inferioris, depressor anguli oris and mentalis
Cervical - platysma

47
Q

ipsilateral hyperacusis (hypersensitive to sound), is due to damage to which nerve?

A

Nerve to stapedius, branch of the facial nerve

48
Q

What are the features of a glioblastoma?

A

Traverses the midline
Central necrosis
Extensive oedema

49
Q

Which cranial nerves are autonomic?

A

III
VII
IX
X

50
Q

What is the most common brain tumour in children?

A

Astrocytoma

51
Q

What is the choroid plexus?

A

a network of blood vessels in each ventricle of the brain, producing the cerebrospinal fluid

52
Q

What is the total volume of CSF?

A

100-150ml

53
Q

What is the normal pressure of CSF?

A

10-15mmHg

54
Q

Where does the cerebral aqueduct lie

A

between 3rd and 4th ventricles

55
Q

What are the 3 types of nerve injury?

A

Neuropraxia - Nerve intact but electrical conduction affected eg crush injury
Axonotmesis - Axon damaged, myelin sheath intact. Wallerian degeneration occurs.
Neurotmesis - Both axon and myelin sheath are damaged. Wallerian degeneration occurs.

56
Q

What is wallerian degeneration?

A

Axonal degeneration distal to the site of injury.
Typically begins 24-36 hours following injury.
Axons are excitable prior to degeneration occurring.
Myelin sheath degenerates and is phagocytosed by tissue macrophages.

57
Q

At what rate does nerve repair occur?

A

1mm/day

58
Q

What type of cell type do gliomas derive from?

A

Neuroglial cells

59
Q

What does CSF pass through to get from the 3rd ventricle to the 4th ventricle?

A

Aqueduct of sylvius

60
Q

What structures do the foramen of munro, magendie and luschka lie between?

A

Munro - lateral ventricles to third ventricle
Magendie and Luschka - fourth ventricle to cisterna magna

61
Q

What is the most common childhood brain tumour?

A

Astrocytoma

62
Q

What structure suspends the spinal cord in the dural sheath?

A

Denticulate ligaments - continuation of the pia mater

63
Q

What is an Ependymoma?

A

Arises from the 4th ventricle and grows through the foramen of Luschka and Magendie
Accounts for 1/3 tumours in children <3 years

64
Q

What is Klumpke’s paralysis?

A

Caused when a baby is delivered with it’s arm extended
Damage to C8-T1
Features:
- Claw hand (MCP joints extended and IP joints flexed)
- Loss of sensation over medial aspect of forearm and hand
- Horner’s syndrome
- Loss of flexors of the wrist

65
Q

What is orbital apex syndrome?

A

Damage to occulomotor (CN III), trochlear (CN IV), abducens (CN VI) and ophthlamic nerves (CN V1) secondary to trauma to the orbital apex and therefore the superior orbital fissure.
Optic nerve also involved.
Symptoms include:
- Complete ophthalmoplegia
- Ptosis
- Ipsilateral vision loss
- Altered cutaneous sensation from the forehead to the vertex

66
Q

What lesion is most likely to occur at the cerebellar pontine angle and what nerve is most likely to be affected?

A

Acoustic neuroma
CN 5 Trigeminal

67
Q

What constitutes lateral medullary syndrome?

A

Nystagmus, ataxia, dysphagia, facial numbness and cranial nerve palsy

WITH CONTRALATERAL HEMISENSORY LOSS

68
Q

What is cushing’s triad?

A

Widening of the pulse pressure
Respiratory changes
Bradycardia

69
Q

Which cranial nerves carry parasympathetic nerve fibres?

A

3
7
9
10

70
Q

Which part of the brain do the cranial nerves originate from?

A

CN1-2 = Cerebrum
CN3-4 = midbrain
CN5-8 = pons
CN9-12 = medulla

71
Q
A