Neuroradiology Flashcards
1
Q
What are the 6 main indications for brain imaging?
A
- Headache/raised ICT
- Seizures
- Weakness/stroke
- Trauma
- Loss of consciousness/neurological deficit
- Post-operative
2
Q
What are the pros of CT?
A
- Excellent bony details/spatial resolution
- Fast
- Compatible with emergency/ICU equipment
3
Q
What are the cons of CT?
A
- poor soft tissue detail/contrast resolution
- No direct muliplanar aquisition
- Radiation
4
Q
What are the pros of MRI?
A
- excellent contrast/soft tissue resolution
- excellent depiction of anatomy
- marrow and cord pathologies
- multiplanar capability
5
Q
What are the cons of MRI?
A
- Less bony detail
- less spatial resolution
- not compatible with pacemakers and many implants
- not compatible with most iCE/emergency equipments
- not as quick as CT
6
Q
How does MRI work?
A
Different sequences using a combination of technical parameters Each sequence is unique and gives different information Overall MRI is correlation of all sequences
7
Q
What is hyperintense on a T1 MRI?
A
Fat and the 4 M’s
- Fat (unless deliberately suppressed)
- Methemoglobin (subacute haematoma)
- Mineral deposition (Ca, Mg, Mn etc)
- Melanin (melanoma)
- Mush (highly proteinaceous fluid)
8
Q
What is the contrast material for T1 MRI?
A
Gadolinium
9
Q
What is hypointense on a T1 MRI?
A
Water, paucity of mobile protons (air, cortical bone)
High flow (e.g. arterial flow voids)
10
Q
What is hyperintense on a T2 MRI?
A
Water
-fluid collections, oedema, demyelination, gliosis, some tumours
Fat
11
Q
What is hypointense on a T2 MRI?
A
- some blood products (subacute haematoma)
- mineral deposition (Ca, Mg, Mn)
- paucity of water or mobile protons (air, cortical bone)
- high flow (arterial flow voids)
