Cerebrovascular Disease & Infections (Martin) Flashcards
Symptoms of an ACA injury
anterior cerebral artery - c/l leg more than the arm or face and “alien hand” syndrome - semiautomatic movements of the c/l arm NOT under voluntary movement
Which vessel injury is associated with “alien hand” syndrome?
anterior cerebral artery (ACA)
Symptoms of an MCA injury
middle cerebral artery - aphasia and face/arm motor loss face preference toward side of lesion
Where would the gaze preference be for a MCA injury?
toward the side of the lesion
What are the 3 main categories of cerebrovascular disease?
- thrombosis
- embolism
- hemorrhage
What is a major risk factor for focal ischemia?
atherosclerosis in hypertension
Watershed infarcts
region between 2 vessels that is the MOST susceptible to ischemia and infarction; will see sickle-shaped band of necrosis
What should you think if you see a sickle-shape band of necrosis?
a watershed infarct
What are the two common sites of a water-shed infarct?
- ACA - MCA: arm and leg weakness and language issues
- MCA - PCA: visual processing
Atherosclerosis typically leads to stenosis of which artery?
internal carotid artery - just beyond the carotid bifurcation
Which vessel is most affected by an embolic infarction?
MCA
Transient Ischemic attacks (TIA’s)
<24 hrs neurological deficit caused by temporary brain ischemia; typically a warning sign and a neurological emergency
At what time are ischemic deficit most probably to produce permanent cell death?
> 10 mins
What are the two types of strokes?
- hemorrhagic (red) - emboli associated
- ischemic (pale) - thrombus associated
Hypertensive cerebrovascular disease produces which type of infarcts?
lacunar infarcts via lenticulostriate arteries
Malignant hypertension is most commonly associated with what type of hemorrhage?
deep brain parenchymal hemorrhages
Chronic hypertension is associated with what?
Charcot-Bouchard microaneurysms
What is the most common cause of a subarachnoid hemorrhage (SAH)
rupture of a saccular (berry) aneurysm (dilation)
A saccular aneurysm typically involves which vessel?
the anterior circulation via the anterior communicating artery
“THE WORST HEADACHE I’VE HAD” should make you think what?
subarachnoid hemorrhage (SAH); 25-50% die; repeat bleeding is common in survivors
What is the most common site for a arteriovenous malformation (AVM)?
subarachnoid space
What is the most common route of CNS infection?
hematogenous - primarily arteries but facial veins possible
herpes simplex and zoster
latent infection of sensory ganglia in Schwann cells and ASCEND to the CNS in SENSORY nerves
Rabies
acetylcholine receptos at the NMJ and ASCENDS to the CNS via MOTOR nerves
What is a major complication of bacterial meningitis?
meningococcemia with rash and b/l adrenal hemorrhage that leads to death (Waterhouse-friderichsen syndrome)
Waterhouse-friderichsen syndrome
b/l adrenal hemorrhage that leads to death following a Nisseria infection (bacterial meningitis)
A gram negative diplococci organism that causes bacterial meningitis?
N. meningitidis
A gram positive diplococci organism that causes bacterial meningitis?
S. pneumoniae
A gram negative pleomorphic organism that causes bacterial meningitis?
H. influenzae
A gram positive cocci organism that causes bacterial meningitis?
S. aureus or S. epidermis
A gram negative bacilli organism that causes bacterial meningitis?
E. coli
What is the most common cause of bacterial meningitis in a newborn (0-6 months)”
Group B Strep
What is the most common cause of bacterial meningitis in a child (6month-6 yrs)?
Strep pneumoniae
What is the most common cause of bacterial meningitis in adolescents/young adults?
N. meningitidis; gram negative diplocci; watch for those in crowded populations; can cause Waterhous-Friderichsen syndrome
What is the most common cause of bacterial meningitis in the elderly?
Strep pneumoniae
CSF findings in a person with a abscess?
high WBCs
high proteins
normal glucose (unlike bacterial)
Neurosyphilis can cause which type of hydrocephalus?
communicating hydrocephalus
In viral meningitis viruses may reach the CNS through which nerves?
olfactory and trigeminal nerves
Herpes simplex virus (HSV-1) typically involves which lobes?
necrotizing and hemorrhagic damage in inferior and medial temporal lobes
What is diagnostic for rabies?
local paresthesias around the wound; infections ascends along MOTOR nerves; can see “foaming at the mouth”
Subacute Sclerosing Panencephalitis (SSPE)
caused by the paramyxovirus; non immunized children following infection with measles; will have cognitive decline, spasticity of limbs and seizures
Nonimmunized children are at risk for developing what after an acute measles infection?
Subacute Sclerosing Panencephalitis (SSPE); cognitive decline, spasticity of limbs and seizures
In which population do you typically see toxoplasmosis gondii infections?
HIV or immunospressed; will see brain abscess and free tachyzoites and encysted bradyzoites
Creutzfeldt-Jackob Disease (CJD)
prion disease rapidly progressive; PrP protein; will see spongiform change (intracellular vacuoles)
