Session 12 Flashcards
Features of radiographs
X ray beam onto plate detector
Quick, cheap, readily available, low ionising radiation dose
Low contrast, 2D
Features of US
Handheld probe using sound waves
Cheap, no ionising radiation
Operator dependent, limited by bone
Useful for thyroid and superficial soft tissue only
Features of CT
X ray beam from passing through a doughnut shaped scanner
Quick, readily available
High radiation dose
Features of MRI
Images acquired from within a magnet- usually shaped like a long tunnel
Best contrast, no ionising radiation
Slow, expensive, limited availability
HNN uses for radiographs
Minor skull trauma (no need for CT)
Cervical spine trauma
Foreign bodies within neck
US HNN uses
Thyroid evaluation
Superficial head and neck masses
Superficial infection
Carotid doppler
CT HNN uses
Trauma- NICE criteria
Acute focal neurological symptoms (evaluate for haemorrhagic strokes)
Malignancy
Infection
Angiographic imaging of arteries and veins
MRI HNN uses
Best imaging of brain - tumour evaluation, epilepsy
Cervical spinal cord traumatic injury
HN tumours
What abnormalities can be seen in a skull radiograph
Skull fracture
Pneumocranium
Fluid level
Lytic soft tissue- Mets/myeloma
Normal lateral skull radiograph
What can be seen on a facial radiograph
Tripod fracture
Black eyebrow
Gas in orbit
TMJ dislocation
Mandibular fracture