Neurosurgery

Question 1

What is the effect of anterior facing herniation?

Answer 1

Suppression of the anterior cerebral artery

Leg weakness

Question 2

What is the effect of herniation into the infraorbital fissure?

Answer 2

CN III damage
4 of 6 extraocular muscles
Parasymp nerve

Question 3

Treatment of raised ICP from CSF:

Answer 3

Drainage

Chronic decrease in production using carbonic anhydrase

Question 4

Treatment of raised ICP from blood:

Answer 4

Bed at 30 degrees to increase venous return
Decrease PCO2
Decrease inflow, increase outflow
Evacuate clot

Question 5

Treatment of raised ICP from brain:

Answer 5

Decrease CMRO2 (oxygen consumption)
Steroids acutely reduce vasogenic swelling from tumour
Remove tumour
Hypertonic solution (e.g. saline 3%)

Question 6

How do you test for brainstem death?

Answer 6

Pupil response
Corneal reflexes
Oculovestibular reflexes
Apnea test

Question 7

Indications for brainstem death:

Answer 7

Hypothermia
Circulatory disturbances
Electrolyte and endocrine disturbances
Lack of reflexes

Question 8

Decorticate posture:

Answer 8

Arm adduction
Elbow flexion
Hand flexion
Plantar flexion

Question 9

Decerebrate posture:

Answer 9

Arm adduction
Elbow extension
Forearm supination
Hand flexion
Plantar flexion

Question 10

How do space-occupying lesions present?

Answer 10

Focal deficits
Seizures
Raised ICP

Question 11

Signs of raised ICP in a neonate?

Answer 11

Head circumference
Fontanelle
Dilated scalp veins
Loss of upgaze
Irritability, vomiting, reduced conscious level

Question 12

MRI modalities:

Answer 12

T1 for contrast (tumours)

T2 for anatomy

Question 13

Communicating causes of hydrocephalus:

Answer 13

Post-haemorrhage

Post-infection

Question 14

Non-communicating (obstructive) causes of hydrocephalus:

Answer 14

Aqueduct stenosis
Obstructed outlets of the 4th ventricle
Foramina of Monro
Tumour
Blood, infection
Membranes and cystic lesions

Question 15

Difference between communicating and non-communicating hydrocephalus:

Answer 15

Communicating = outflow obstruction outside of the ventricles (flow between the ventricles)
Non-communicating = outflow obstruction in the ventricles

Question 16

Triad of features in normal pressure hydrocephalus:

Answer 16

Dementia or bradyphrenia (slowness of thought)
Urinary incontinence
Gait difficulties (similar to Parkinson’s)

Question 17

Imaging of normal pressure hydrocephalus:

Answer 17

Hydrocephalus with enlarged 4th ventricle

Absence in sulcal atrophy

Question 18

Treatment for normal pressure hydrocephalus:

Answer 18

Ventriculoperitoneal shunting

10% experience serious complications such as seizure, infection and intracerebral haemorrhage

Question 19

Most common solid tumour in children/2nd most common cancer in children to leukaemia?

Answer 19

Posterior fossa brain tumour

Question 20

Effect of pineal tumour?

Answer 20

Can cause hydrocephalus by compressing the aqueduct

Question 21

History of aneurysm?

Answer 21

Crescendo over seconds to a really bad headache

Question 22

Risk factor for aneurysms:

Answer 22

Connective tissue disorders

Question 23

Poor prognostic factor in aneurysm:

Answer 23

Vasospasm

Give nimodipine

Question 24

Extradural tumour:

Answer 24

Metastases from prostate cancer

Question 25

Intradural tumours:

Answer 25

Meningioma | Neurofibroma

Question 26

Intramedullary tumours:

Answer 26

Astrocytoma Ependymoma Haemangioblastoma Cavernoma

Question 27

Presentation of hydrocephalus in older children/adults:

Answer 27

Headaches N+V Visual blurring +/- loss of upgaze Drowsiness, reduced conscious level

Question 28

Imaging in hydrocephalus:

Answer 28

US in neonates | Need higher resolution before intervention like CT or MRI to observe flow

Question 29

Temporary treatment of hydrocephalus:

Answer 29

Extra-ventricular drain Ventriculosubgaleal shunts (drains to under scalp) Resevoir

Question 30

Definitive treatment of hydrocephalus:

Answer 30

Shunt ETV Fenestrations Stents

Question 31

Head injury severity by GCS:

Answer 31

``` Mild = 13-15 Moderate = 9-12 Severe = 3-8 ```

Question 32

What causes subdural haematomas?

Answer 32

Rupture of bridging veins or burst lobes in severe head injury

Question 33

What causes extradural haematomas?

Answer 33

Fracture lacerating dural artery MMA Venous sinus injury May have lucid interval

Question 34

What are multiple small contusions (petechial haemorrhages) a sign of?

Answer 34

Diffuse axonal injury

Question 35

Management of DAI pre-surgery?

Answer 35

Insertion of ICP probe to monitor

Question 36

Management of brain tumours:

Answer 36

Initially steroids to reduce swelling AEDs if needed MRI of whole neuraxis and CT CAP Surgery

Question 37

Management of glioblastoma?

Answer 37

High grade glioma Resection and chemoradiation Prognosis is 1.5 years

Question 38

Management of single metastasis?

Answer 38

Resection

Question 39

Low grade gliomas will...

Answer 39

Transform to high grade within 15 years | Maximal resections carried out to prevent this

Question 40

Management of malignant tumours e.g. medullary blastoma in neonate?

Answer 40

Resection with curative intent and adjuvant therapy | Avoid RT/proton beam in first 3 years of life

Question 41

Astrocytoma treatment?

Answer 41

Maximal safe resection

Question 42

What is a cavernoma?

Answer 42

Cluster of abnormal blood vessels typically in CNS Thin walls, prone to leaking Can cause seizures, strokes, haemorrhages and headaches

Question 43

Where do hypertensive bleeds tend to occur?

Answer 43

Basal ganglia | Cerebellum and brainstem but to a lesser extent

Question 44

Management of aneurysm?

Answer 44

HDU/ITU Analgesia, laxatives, fluids Nimodipine CT angiogram to discuss coiling/clipping

Question 45

Spinal tumours:

Answer 45

Extradural > intramural > intramedullary

Question 46

Grade A spinal trauma:

Answer 46

Complete. No motor or sensory in sacral segments S4-5

Question 47

Grade B spinal trauma:

Answer 47

Incomplete. Motor below neurological level but no sensory. Includes sacral segments S4-5

Question 48

Grade C spinal trauma:

Answer 48

Incomplete. Motor below neurological level and more than half muscles below neurological level have grade 3 or less

Question 49

Grade D spinal trauma:

Answer 49

Incomplete. Motor below neurological level and more than half muscles below neurological level have grade 3 or more

Question 50

Grade E spinal trauma:

Answer 50

Normal. Motor and sensory intact