Week 1 - Trachte/Kraft Flashcards
(32 cards)
What are the two types of cerebral edema?
- Vasogenic Cerebral Edema
2. Cytotoxic Cerebral Edema
What occurs in Vasogenic Cerebral Edema?
- Increased Vascular Permeability (leaky junctions in vessels –> fill with fluid –> swelling!)
- Fluid shifts into intracellular spaces in the brain
What causes Vasogenic Cerebral Edema?
- Localized edema due to tumor/abscess
- Generalized edema due to trauma
What causes in Cytotoxic Cerebral Edema?
-Cell membrane injury due to hypoxia or metabolic damage
What occurs in Cytotoxic Cerebral Edema?
- Individual cells swell and retain fluid
- Increased intracellular fluid in endothelial cells of the vessels, but cell junctions are okay
- Cells swell due to retained fluid
What is the normal pathway of circulation of CSF starting in the lateral ventricles?
- Made in choroid plexus of lateral ventricles
- Circulates through intraventricular foramen –> 3rd ventricle
- Passes through cerebral aquaduct –> 4th ventricle
- Moves down brainstem via central canal
- Travels laterally to venus dural sinus –> arachnoid granules
- Enters Superior sagittal sinus –> straight sinus –> confluence of sinuses
- Follows Transverse sinus –> sigmoid sinus
- Finally enters INTERNAL JUGULAR VEIN
What is the normal pathway of circulation of CSF starting in the fourth ventricle?
- Made in choroid plexus of fourth ventricle
- Circulates through median aperature
- Travels around Cerebellum
- Empties into occipital sinus –> Confluence of sinuses
- Follows Transverse sinus –> sigmoid sinus
- Finally enters INTERNAL JUGULAR VEIN
What is Noncommunicating Hydrocephalus?
- Blockage in the ventricular system that does not allow CSF flow in that area
- Only part of the ventricular system is enlarged
What are the causes of Noncommunicating Hydrocephalus?
-Congenital malformation, tumor, abscess, hematoma
What is Communicating Hydrocephalus?
- Blockage in subarachnoid space
- Enlarges the entire ventricular system
- Blocks the exit!
What are the causes of Communicating Hydrocephalus?
- Resolving meningitis
- Subarachnoid hemorrhage
- Dural sinus thrombosis
What is Hydrocephalus Ex Vacuo?
- Dilation of the ventricular system due to brain atrophy with compensatory increase in CSF volume
- No blockage in the ventricular system
What are potential causes of Hydrocephalus Ex Vacuo?
- Alzheimer’s disease
- Pick disease
- Being on a ventilator for an extended period of time
What is Increased CSF Production Hydrocephalus?
- Dilation of the ventricular system due to increased CSF production
- Uncommon
What causes Increased CSF Production Hydrocephalus?
Choroid plexus papilloma
What is Normal Pressure Hydrocephalus?
- Reversible enlargement of the ventricles
- May be a form of communicating hydrocephalus
- No cortical atrophy
What are the clinical features of Normal Pressure Hydrocephalus?
- Elderly patient with: gait disturbance, urinary incontinence, and dementia
- Often misdiagnosed as Alzheimer’s disease
What are the causes of increased intracranial pressure?
- Mass effect
- Edema
- Tumor
- Hematoma
What is the problem with increased intracranial pressure?
Compromises blood flow to the brain
What are the symptoms of increased intracranial pressure?
Headache, papilledema, decreased LOC
What are the three main types of herniation that can result from increased intracranial pressure?
- Subfalcine (Cingulate) Herniation
- Transtentorial (Uncinate) Herniation
- Tonsillar Herniation
What are the symptoms of herniation?
- Focal neurologic symptoms
- Respiratory arrest
- Cardiac arrest
- Coma
- Death
What is a Subfalcine (Cingulate) Herniation?
-Expansion of one hemisphere displaces the cingulate gyrus under the falx causing compression of the anterior cerebral artery
What are the specific symptoms of a Subfalcine (Cingulate) Herniation?
- Weakness of limbs
- Aphasia
