Brain

Question 1

What is an Arnold Chiari Malformation?

Answer 1

A condition affecting the brain. Consists of a downward displacement of the cerebellar tonsils through the foramen magnum causing non-communicating hydrocephalus as a result of obstruction of CSF outflow

Question 2

Where do meningioma arise from?

Answer 2

The arachnoid “cap” cells of the arachnoid villi in the meninges

Question 3

What structures do meningioma’s lie between

Answer 3

Falx and cerebral hemisphere

Question 4

What are of the body is represented on the medial side of the motor area?

Answer 4

Lower limbs (feet nearest the midline)

Question 5

What area is located in the pre-central gyrus of the brain?

Answer 5

The primary motor cortex

Question 6

Which layer of meninges is a meningioma attached to?

Answer 6

The dura

Question 7

What type of contrast is used for an MRI brain

Answer 7

Gadolinium

Question 8

What is meant by ring enhancement?

Answer 8

An abnormal radiological sign on MRI or CT using radiocontrast.
On the image there is an area of increased density surrounded by a bright rim from concentration of the enhancing contrast dye
This enhancement may represent breakdown of the blood brain barrier and the development of an inflammatory capsule

Question 9

What are the differential diagnoses for ring enhancement?

Answer 9

Metastasis
Abscess
Glioblastoma
Infarct (subacute phase)
Contusion
Demyelinating disease
Radiation necrosis or resolving haematoma

Question 10

What is the aggressive form of glioma

Answer 10

Glioblastoma multiforme

Question 11

How does CSF circulate

Answer 11

Produced by the choroid plexuses within the lateral ventricles > Interventricular foramen (Foramen of Monroe) > Third ventricle > aqueduct of sylvius > fourth ventricle > Foramen of Luschkam and Magendie > Subarachnoid space > arachnoid villi > superior sagittal sinus

Question 12

What is the circle of Willis?

Answer 12

An anastomosis between the internal carotid arterties and vertebral arteries on the inferior surface of the brain

Question 13

What is the circle of Willis formed from?

Answer 13

Anterior communicating artery
Anterior cerebral artery
Internal carotid artery
Posterior communicating artery
Posterior cerebral arteries and the termination of the basilar artery

Question 14

What are the features of the vertebral arteries?

Answer 14

Enter the cranial canal via the foramen magnum
Lie in the subarachnoid space
Ascend on anterior surface of the medulla oblongata
Unite to form the basilar artery at the base of the pons

Question 15

What are the branches of the vertebral arteries?

Answer 15

Posterior spinal artery
Anterior spinal artery
Posterior inferior cerebellar artery

Question 16

What are the branches of the basilar artery?

Answer 16

Anterior inferior cerebellar artery
Labyrinthine artery
Pontine artery
Superior cerebellar artery
Posterior cerebellar artery

Question 17

What are the branches of the internal carotid artery?

Answer 17

Posterior communicating artery
Anterior cerebral antery
Middle cerebral artery
Anterior choroid artery

Question 18

What is the entry of the vertebral artery into the skull?

Answer 18

Vertebral artery enters the skull through the foramen magnum
It crosses transversely across the posterior arch of the atlas

Question 19

What is the course of the vertebral artery?

Answer 19

Inside the skull, the 2 vertebral arteries pass upwards, forwards and medially in the subarachnoid space to reach the anterior aspect of the medulla oblongata, then they unite together at the lower border of the pons to form the basilar artery

Question 20

What do the Vertebral and basilar arteries supply within the brain?

Answer 20

The vertebrobasilar artery system supplies the medulla, cerebellum, pons, midbrain, thalamus and occipital cortex

Question 21

Which vein drains the dangerous area of the face?

Answer 21

Inferior ophthalmic vein

Question 22

Where does the ICA enter the skull and what is it’s course?

Answer 22

Enters the skull via the carotid canal in the petrous part of the temporal bone

Question 23

What branch is given off the ICA before the anterior and middle cerebral arteries?

Answer 23

Ophthalmic artery

Question 24

What condition does a berry aneurysm lead to?

Answer 24

Subarachnoid haemorrhage

Question 25

What are the signs of an MCA infarct?

Answer 25

Hemiplegia of the lower 1/2 of the contralateral face
Hemiplegia of the upper and lower extremities
Aphasia if in the dominant hemisphere

Question 26

What is the anterior attachment of tentorium cerebelli?

Answer 26

Superior angle of the petrous part of temporal bone

Question 27

Which blood vessel supplies the inner table of the temporal bone?

Answer 27

Middle meningeal artery

Question 28

If there is a tumour in the precentral gyrus which bone should be penetrated to get to the tumour?

Answer 28

Parietal bone

Question 29

Relationship between ICP and oculomotor nerve?

Answer 29

An increase in ICP leading to a oculomotor nerve palsy which leads to a dilated pupil

Question 30

What are false localising signs?

Answer 30

Neurological signs which reflect dysfunction distant or remote from the expected anatomical locus of pathology. They occur in two major contexts - as a consequence of raised ICP or with spinal lesions

Question 31

Which muscles are supplied by the oculomotor nerve?

Answer 31

Levator palpebrae superioris
Superior rectus
Inferior rectus
Medial rectus
Sympathetic fibres to Muller’s muscle
Inferior oblique
Sphincter pupillae

Question 32

Paralysis of the oculomotor nerve leads to

Answer 32

THe eye being displaced downwards and outwards

Outward because the lateral rectus maintains muscle tone in comparison to the paralyed medial rectus as it is supplied by CN VI

Downwards because the superior oblique is un-anatgonised by the paralysed superior rectus, inferior rectus and inferior oblique

They will also have ptosis and mydriasis

Question 33

What is the structure on which the oculomotor nerve is pressed against?

Answer 33

Petrous part of the temporal bone, attached border of the tentorium cerebelli