Interpreting CT Head
Mnemonic: Blood Can Be Very Bad (Bloods, Cisterns, Brain, Ventricles,
Bone)
CT Head Basics:
Appearance of tissues on CT head should be described in terms of
density
Darker structures = hypodense/low density
Brighter structures = hyperdense/high density
Format:
1. Confirm patient details
- Patient name, hospital number, DOB
- Date and time of the scan
- Any previous scans if available for comparison
2. Confirm type of scan
- I am looking at a axial/coronal/sagittal non contrast CT head.
3. Blood
- Blood can vary in appearance depending on age
- Acute haematoma = hyperdense
- Chronic haematoma = hypodense
- Types: extradural, subdural, subarachnoid, intracerebral
, Extradural
- Bleed between dura matter and skull
- Mostly due to rupture of middle meningeal artery due to
fractured pterion (look for fracture)
- Presentation: immediate LOC and then period of lucidity, followed
by progressive decline
- CT = bi-convex lemon shaped hyperdense mass, bleeding limited
to suture lines of
the skull (bleeding
does not spread),
midline shift,
brainstem
herniation
Subdural
- Bleed between dura mater and arachnoid matter
- Due to rupture of bridging veins after trauma to temporal side of
head
- Common in older patients due to increased risk of falls and
coagulation abnormalities
- Presentation: headache, n+v, confusion
- CT head = crescent banana shaped hyperdense mass, bleeding
is not limited by suture lines (spreads everywhere), midline shift,
compression of ventricles, sulcal effacement
Mnemonic: Blood Can Be Very Bad (Bloods, Cisterns, Brain, Ventricles,
Bone)
CT Head Basics:
Appearance of tissues on CT head should be described in terms of
density
Darker structures = hypodense/low density
Brighter structures = hyperdense/high density
Format:
1. Confirm patient details
- Patient name, hospital number, DOB
- Date and time of the scan
- Any previous scans if available for comparison
2. Confirm type of scan
- I am looking at a axial/coronal/sagittal non contrast CT head.
3. Blood
- Blood can vary in appearance depending on age
- Acute haematoma = hyperdense
- Chronic haematoma = hypodense
- Types: extradural, subdural, subarachnoid, intracerebral
, Extradural
- Bleed between dura matter and skull
- Mostly due to rupture of middle meningeal artery due to
fractured pterion (look for fracture)
- Presentation: immediate LOC and then period of lucidity, followed
by progressive decline
- CT = bi-convex lemon shaped hyperdense mass, bleeding limited
to suture lines of
the skull (bleeding
does not spread),
midline shift,
brainstem
herniation
Subdural
- Bleed between dura mater and arachnoid matter
- Due to rupture of bridging veins after trauma to temporal side of
head
- Common in older patients due to increased risk of falls and
coagulation abnormalities
- Presentation: headache, n+v, confusion
- CT head = crescent banana shaped hyperdense mass, bleeding
is not limited by suture lines (spreads everywhere), midline shift,
compression of ventricles, sulcal effacement
