Diagnostic radiology: neuroradiology Flashcards
What is the density of blood, fat, soft tissue and calcium in CT scan?
How can you tell the difference between T1 and T2 weighted MRI via CSF, spinal cord and muscle?
What are pros and cons of MRI for radiation, cost, duration, bone assessment, soft tissue assessment, incompatible devices
What IV contrast is used for CT and MRI?
CT: iodine
MRI: gadolinium
What imaging can be used for aneurysms, vascular malformations, large vessel arterial occlusion, stenosis or dissection?
CT/MR angiogram
What imaging can be used for dural venous sinus thrombosis?
CT/MR cerebral venogram
What imaging can be used for planning of neuroendovascular treatment?
Digital subtraction angiography which is more invasive
What imaging used for extra-cranial carotid stenosis?
Doppler USG
What imaging would be used to detect IVH in preterm infants and what condition does it have to meet?
Ultrasound infant brain
Only possible if fontanelles are still wide open
What are advanced neuroimaging?
CT perfusion
MR perfusion
MR spectroscopy
Diffusion tensor imaging
Functional MRI
Weigh the pros and cons of plain radiograph, CT and MRI for radiation, cost, duration, bone assessmentm soft tissue assessment and other non radiation related contraindications
What imaging used for spinal trauma?
- Plain radiographs
- Plain CT
‒ High sensitivity and specificity - Plain MRI
− ligamentous, spinal cord and soft tissue injuries
− neurological deficits not explained by plain film or CT
What imaging used for spinal cord compression and the possible clinical presentation?
- Clinical presentation
− Motor deficit, sensory level, incontinence +/- urinary retention - Plain radiographs / CT
− Collapse, destructive bone lesions, retropulsion - MRI
− Allows visualization of the cord
What are the indications for imaging in head injury?
Low GCS, skull fracture, seizure, focal neurological deficit, multiple vomiting, retrograde amnesia
Clotting disorder, anticoagulation
High energy trauma
Infants with large scalp soft tissue injury, suspected non accidental injury, tense fontanelle
What is 1st line imaging for head injury?
Plain CT brain to visualize hemorrhage and skull fractures
Skull radiograph not beneficial as cannot exclude intracranial hemorrhage and can only detect fractures
What is 1st line imaging for seizures?
What other imaging may be considered?
Plain CT brain in acute/emergency settings
Detect hemorrhage or calcific lesion
Contrast CT brain if suspecting intracranial infection, tumor, inflammatory lesion, vascular pathology
MRI: sensitive to subtle lesions e.g. malformations
+ contrast if suspecting intracranial infection, tumor, inflammatory lesion, vascular pathology
What are advanced imaging techniques used for seizures?
Pre-operative planning: SPECT, FDG PET/CT, functional MRI
What are the indications for skull imaging in acute headache?
Thunderclap headache
Redflag signs: new onset, history of cancer or immunodeficiency, clotting problem, anticoagulation, associated mental state change, meningitis features, focal neurology and progressive deterioration
What is 1st line imaging used for acute headache when there is indication?
Plain CT brain to visualize blood, space occupying lesion
What is the imaging done for acute stroke?
Plain CT brain to delineate extent and location, exclude hemorrhage before thrombolytic or antiplatelet therapy
Intra-arterial thrombectomy: selected cases within therapeutic time window
CT cerebral angiogram for planning
MRI brain
DWI: more sensitive than CT in acute stroke
Perfusion MRI for salvageable brain tissue
Long scanning time and waiting time limits role of MRI in acute setting
When is IV contrast indicated in acute setting?
Plain CT is the imaging of choice in most acute settings
IV contrast for abscess, metastases/tumor, venous sinus thrombosis, CT angiogram