Neuroradiology

Question 1

Imaging Modalities for muscles

Answer 1

MRI- can be helpful in myopathies
Genetic> inflammatory
Genetic= distribution of affected muscles

Question 2

Imagining Modalities for Peripheral nerves

Answer 2

• Ultrasound- can be helpful in assessing nerve entrapment syndromes (carpal tunnel, ulnar nerve)
• MRI= rarely used but a topic of research interest

Question 3

Imagining Modalities for Plexii (brachial, lumbosacral)

Answer 3

MRI

Question 4

Imagining Modalities for Spinal cord (cord and roots)

Answer 4

-MRI- gold standard
-CT- can be used when MR contraindicated or not possible
Spinal cord compression, spondylosis, stroke, inflammation

Question 5

Imagining Modalities for Brain

Answer 5

• MRI= most detailed imaging of brain structures and pathology
• CT= fast, can be used when MR not possible, sensitive for detecting haemorrhage (good in acute setting)
• Nuclear Medicine= DaTscan helpful in Parkinson’s disease, SPECT can be helpful in dementias, PET scans rarely used (expensive, hard to source isotopes)

Question 6

Imagining Modalities for Blood vessels

Answer 6

• Doppler Ultrasound= useful for carotid vessel assessment, bedside
• CT and MR angiography= both used extensively (cerebral vessels, aneurisms)
• Angiography (DSA)= less commonly used but remains gold standard for intracranial assessment
• CT and MR venography= both used extensively

Question 7

Describe the CT Brain

Answer 7

• 3D X-Ray
• Fast, well-tolerated (ventilatory support, metal in body)
• Workhouse in emergency situations
• Good at detecting blood= sub-arachnoid haemorrhage, intracerebral haemorrhage, subdural/ extradural haematoma
• Blood shows up as white, swelling, midline shift

Question 8

What are the key sequences of MRI brain scans?

Answer 8

• T1-weighted= good for anatomy, best detail, CSF is black
• T2-weighted= good for pathology, CSF is white, most pathology has increased water in it
• Flair= T2 with supressed CSF, good for pathology near the ventricles

Question 9

How is muscle MRI used?

Answer 9

• Identification of oedema and fatty replacement of muscle tissue
• Inherited myopathies= identify preferentially involved and preferentially spared muscle
• Selecting muscle for biopsy
• Assessing response for treatment in clinical trials