Brain contusions Flashcards
Brain contusions
- Focal surface bruises – bleeding, cell death, oedema
- Crests of gyri - temporal gyri
- Wedge shaped – broad base at surface - frontal lobe
- Often in association with SAH
coup
Under site of impact due to compression forces
contreceoup
opposite
impact of crest of gyri > rupture of blood vessels
- temporal and frontal lobe most common
Glasgow Coma Scale (GCS) score
3 categories: eye opening, best verbal response, best motor response
total GCS 1 - 15
Lowest GCS score in the 1st 48 hours
brain injuries - mortality rate
return to consciousness within less than 6hrs
no mortality
What is the imaging modality of choice in the acute situation?
Is there a treatable lesion?
• unenhanced brain CT scan
• readily available
• fast & accurate for detecting acute intracranial hemorrhage
• on CT, acute haemorrhage is hyperdense to brain
• may display mass effect
• sensitive in distinguishing brain contusions from extra-axial
haematomas (subdural and epidural)
• excellent for detecting depressed facial and calvarial fractures
What is the imaging modality of choice in the acute situation? 2
Significant residual neurological and behavioural deficits in patients with normal CT scans:
• T2 MR superior in detecting subacute & chronic contusions
• especially inferior frontal & temporal regions & brainstem
Hesselink 1998
Multivoxel proton MR spectroscopy (H-MRS)
Quantification of metabolites indicative of different processes
Mild Traumatic Brain Injury
• Most common type of TBI • GCS13-15 • Loss of consciousness < 30 min’s • Post-traumatic amnesia < 24 hours • No macroscopic damage Mild TBI often persisting difficulties with concentration & memory
MTBI - Clinical manifestations
Physical:
Fatigue, nausea, altered equilibrium, vision, hearing
Cognitive:
Attention, memory, processing, reasoning
Mood & Behaviour:
Insomnia, irritability, depression, anxiety
Review of 876 patients with a mild TBI (GCS 13-15) and a skull # &/or intracranial haemorrhage on initial CT scan:
can have progression with bleed so get CT • 91.3% had ICH • 33.3% had skull # 1. Subdural 41% 2. Intra-parenchymal 34.1% 3. Epidural 6.7% 4. Subarachnoid 2.8%
** in moderate & severe TBI
SAH & SDH most common
13.1% had progression on RHCT!!!
greatest predictors for neurosurgical intervention
“a mild GCS score (GCS 13–15) in patients with an intracranial injury does not preclude progression on repeat head CT and the need for a neurosurgical intervention.”
• Base deficit >/= 4
• displaced skull fracture
• subdural or epidural haematoma >/= 10mm
are the greatest predictors for neurosurgical intervention in patients with mild TBI and an intracranial injury.
Chronic affects of TBI
• Dementia / Alzheimer’s disease
• Parkinson’s disease
• Amyotrophic lateral sclerosis
Retired athletes with history of >/= 3 concussions reported: 3-fold increase in
• significant memory impairment • diagnosed depression
Ischaemic stroke
most common - interruption to circulation
1. Thrombotic = when a blood clot, called a thrombus, blocks an artery to the
brain and stops blood flow.
2. Embolic = when a piece of plaque or thrombus travels from its original site and blocks an artery downstream. The material that has moved is called an embolus.
Haemorrhagic stroke
caused by:
1. hypertension
2. rupture of an aneurysm or
3. vascular malformation
4. complication of anticoagulation medications
An intracerebral haemorrhage (ICH) = bleeding directly into the brain tissue, which often forms a clot within the brain.
A subarachnoid haemorrhage (SAH) = bleeding fills the subarachnoid space. Morbidity (not fully functionO & mortality: SAH > ICH > ischaemic stroke
Spontaneous subarachnoid haemorrhage
• Accounts for 5% of strokes (less common than ICH or ischaemic stroke)
• High morbidity & mortality
- 85% of cases = rupture of intracranial aneurysm
- Saccular cerebral aneurysms = acquired lesions that develop at branch points of
major arteries of the circle of Willis
- degeneration of the internal elastic lamina with secondary thinning / loss of the
tunica media
- average size 6-7mm at rupture = rapid blood loss into subarachnoid space
Spontaneous subarachnoid haemorrhage
1. Early brain injury: • Transient global ischaemia • Toxic effects of blood in subarachnoid space 2. Delayed cerebral ischaemia - 1/3 patients in 3 – 14 days after haemorrhage 3. Systemic response: • Increased sympathetic NS activity • Angiotensin system activation • Inflammatory cytokines
Spontaneous subarachnoid haemorrhage Diagnosis:
- Most severe headache of a person’s life
- Suddenonset**-reachesmaximumseverityin<1min 3. Neckpain/stiffness
- Non-contrast CT +/- lumbar puncture
