Head
CT
Evaluation
Initial Review
Correct pt
Without IV contrast
Look for suspected clinical findings
- then use scan to enhance physical exam.
Scalp
Contusion, swelling.
Skull
Look for #s
- suture lines may be mistaken
- depressed --> neuro consult
- open --> neuro consult
Gyri/Sulci
Symmetry
If asymmetrical, consider
- acute subdural: increased density, whole hemisphere, inside skull,
may cause shift, associated cerebral contusions
- extradural: lenticular / biconvex, in skull (compress brain),
shift
midline, temporal/temporoparietal.
Cerebral/Cerebellar
Density & symmetry
Haematomas are high density and large
Contusions are punctate and high density
Diffuse axonal injury is normal or scattered contusions / low
densities.
Ventricles
Assess for size / symmetry
Significant mass lesions distort the ventricles (esp laterally)
High ICP lowers ventricular size
Intraventricular haemorrhage shows as bright spots.
Shift
Septum pallucidum between lat ventricles should be in midline
Midline is from crysta galli anteriorly to inion posteriorly
--> shifts of >5mm often
indicate need for surgical evacuation.
Maxillofacial
#s/crepitus
Sinuses/mastoids for air-fluid levels
All may indicate basal skull #s.
Four
Cs
of increased density:
Contrast
Clot
Cells (tumour)
Calcification (pineal gland, choroid plexus)