Section 4 - Meninges Flashcards
Why can space-occupying lesions be traumatic?
Meninges are very durable, but increase in brain volume can compress healthy tissue.
What is a congenital dermal sinus?
Failure of ectoderm to pinch off from the neuroectoderm and meninges; commonly causes recurrent meningitis
What can cause an extradural (epidural) hematoma?
Head trauma - periosteal dura can loosen and damage middle meningeal artery or accessory meningeal artery
What happen in an epidural hematoma?
Extravascular blood dissects periosteal dura from skull - epidural hematoma. Looks SHORT AND WIDE.
What are symptoms of an epidural hematoma?
- Similar to increase in ICP (headache, disorientation, confusion, lethargy, unresponsiveness)
What is Talk and Die syndrome?
Patient is initially rendered unconscious. He/she has a lucid interval (awake and conversant), but then deteriorates and dies suddenly. Happens with EPIDURAL HEMATOMA.
What is a dural border / subdural hematoma?
Bleeding below meningeal dura within dural border cell layer (adjacent to arachnoid) –> cell layer splits and creates space at dura-arachnoid interface. LONG AND THIN hematoma.
What causes a dural border / subdural hematoma?
Typically, bleeding from a bridging vein passing through subarachnoid space to enter venous sinus.
Acute subdural hematoma is caused by:
Chronic subdural hematoma is caused by:
- hemorrhage or contusion
- brain atrophy with chronic bleeds (elderly)
What is a hygroma?
Tearing of arachnoid membrane due to skull trauma causes the CSF to dissect and open dural border cell layer
What causes a subdural hematoma?
Head trauma shifts the brain enough to tear a large vein before in enters the sinus OR hemorrhage of vessels within the subarachnoid space.
- Blood can migrate to cisterns or outline brain divisions or dural reflections
What is the main sign of a subarachnoid hematoma?
Blood in the CSF
A nontraumatic or spontaneous subarachnoid hemorrhage is caused by:
Rupture of intracranial aneurysm
A primary aneurysm is:
A secondary aneurysm is:
- one dilated from birth
- one dilated by systemic problems (hypertension)
List symptoms of aneurysm rupture:
- THUNDERCLAP HEADACHE
- neck stiffness
- vomiting/nausea
- depression
- loss of consciousness
List warning signs of an impending subarachnoid hemorrhage (leaking aneurysm):
- Intermittent headache
- Nausea/vomiting
- Fainting spells (syncope)
What is a duret hemorrhage?
Small, linear bleeding in ventral/paramedial brainstem (pons and medulla) from traumatic downward displacement of brainstem.