Subdural haemorrhage Flashcards
what is responsible for subdural haemorrhage?
bleeding due to shearing forces that tear bridging veins
what is the typical presentation of a subdural haemorrhage?
elderly patient presenting with;
- headache
- nausea/vomiting
- focal neurological deficit
- confusion
- decreasing GCS
typically present in the subacute phase (3 days - 3 weeks) or chronic (> 3 weeks)
what feature on CT scan is indicative of a chronic SDH?
crescent/biconvex shape homogenous hypodensity extra-axial collection
what feature on CT scan is indicative of an acute SDH?
crescent/biconvex shape homogenous hyper dense extra-axial collection
what are risk factors for SDH?
advancing age (>65yrs) anticoagulation therapy clotting disorder chronic alcoholism recent trauma hx of falls
a patient with diagnosed chronic SDH has ipsilateral weakness. what is this termed as?
Kerrnohan - Woltman phenomenon
what is the indications of surgery for SDH?
thickness of clot > 15mm
midline shift > 5mm
progressive increase on serial imaging
neurological deficit
why is a sub-galeal drain inserted during surgical evacuation of the clot?
reduces risk of chronic SDH reoccurring and pneumocephalus (air/gas within the cranial cavity)
what are the complications of surgical management of SDH?
pneumocephalus infection reoccurrence seizures damage to surrounding brain structures bleeding coma death
what sign on CT scan is suggestive of tension pneumocephalus?
mount fuji sign
what is pneumocephalus and how is it diagnosed?
air or gas within the cranial cavity
cross-sectional head CT with mount fuji sign
what are the different phases of presentation of SDH?
hyperacute < 1 hr
acute 1hr - 3 days
subacute 3 days - 3 weeks
chronic > 3 weeks
what is the difference in appearances of SDH depending on when it presents?
hyperacute (< 1hr)
- Isodense
acute (1hr - 3 days)
- hyperdense (white)
subacute (3days - 3 weeks)
- becomes less dense, harder to identify
- require contrast enhancing CT/MRI
chronic (> 3 weeks)
- hypodense (black)
