Neuroradiology

Question 1

List indications to perform a CT scan

Answer 1

• Head trauma: NICE guidelines
• Acute stroke: NICE guidelines
• Headache: SIGN guidelines, red flags for suspected tumour or subarachnoid haemorrhage
• Cancer: looking for metastatic brain tumours in patients with symptoms
• Post-surgical: hydrocephalus, haemorrhage

Question 2

List indications to perform an MRI scan

Answer 2

Mostly under specialist physicians:

• Demyelination
• CNS tumours
• Spine – for intervertebral disc prolapse
• Transient ischaemic attacks
• Epilepsy
• Paediatric neurology
• Headache

Question 3

State contraindications to perform an MRI scan

Answer 3

Implanted electronics (check with manufacturer)
Most cardiac pacemakers, implantable defibrillators, cochlear implants
Relative contraindication for programmable shunts, insulin pumps
Moveable metallic implants (check make and model): Aneurysm clips, heart valves, recent intra-abdominal clips
Relative contraindications - Claustrophobia, pregnancy, tattoos

Question 4

Understand the uses of angiography in the diagnosis of neurological pathology

Answer 4

Large vascular (arterial and venous) abnormalities Diagnosis and treatment 1.Aneurysm 2.Arteriovenous malformation 3.Carotidocavernous fistula 4.Unstoppable epistaxis

Question 5

Advantages vs Disadvantages

Plain radiographs

Answer 5

Advantages
Almost universal availability
Fast
Sequential images in subtraction angiography

Disadvantages
Lacks soft tissue detail

Question 6

Ultrasound adv vs disadv

Answer 6

Advantages
No radiation
Less expensive equipment
Can be performed in the neonatal unit
Movement tolerant

Disadvantages
Requires a wide enough open fontanelle i.e. up to about 1 year of age
Image quality and interpretation based on operator skill

Question 7

CT adv vs disadv

Answer 7

Advantages

• Rapid
• Metal and pacemaker tolerance
• Good for demonstrating acute haemorrhage

Disadvantages

• Radiation 2mSv
• More expensive cumbersome equipment

Question 8

Radionuclide radiology

Answer 8

Advantages   
Physiological information: 
-Glucose metabolism 
-Perfusion
-Dopamine reuptake receptors

Disadvantages
Unclear anatomical information
Medium cost of equipment
Radiotracers can be expensive

Question 9

MRI adv vs disadv

Answer 9

Advantages
No radiation
Soft tissue differentiation
Physiological information: blood flow, diffusion restriction, metabolite concentrations

Disadvantages
Poor tolerance of metalwork
Magnetic sensitive electronics may fail or are contraindicated
Pacemakers!
Cochlear implants absolutely contraindicated
Least movement tolerance
Slow, must limit sequences
Most expensive equipment
Danger of metallic objects becoming projectiles