CC Nov 2015 Basilar artery occlusion

echoecho's version from 2015-11-30 19:40


Question Answer
What arterties join at the pontomedullary junction to form the basilar artery?veterbral arteries
What brances does the basilar artery give rise to as it lies on the ventral surface of the pons?1) median 2) paramedian 3) short circumferential 4) long circumferential
What branch supplies significant portions of the pons and middle cerebellum?anterior inferior cerebellar artery
What is the name of the terminal branch of the basilar artery? What does it supply?1) posterior cerebral artery 2) midbrain, thalamus, medial portions of the temporal and occipital lobs
List the risk factors for basilar artery occlusion (which are the same as for CVA)?1) HTN (most common risk fx) 2) DM 3) CAD 4) PVD 5) tobacco use 6) dyslipidemia
What is the etiology when occlusion occurs at the middle segment of the basilar artery?artherosclerotic occlusion
What is the etiology when occlusion occurs at the distal segment and vertebrobasilar junction?embolism
What may occur in the extracranial vertebral arteries after neck trauma?arterial dissection
Basilar artery occlusion is more common in what gender, age group, ethnic group?male; elderly; African Americans
What is the mortality rate of acute, untreated basilar artery occlusion?85%
The prognosis in patients is worse when what is present?1) decreased level of consciousness 2) dysarthria 3) pupillary abnormalities 4) bulbar symptoms 5) diplopia 6) bilateral cerebellar lesions 7) tetraplegia 8) when a cardiac embolism is the cause of the occlusion
Patients with artherosclerotic disease may present with what course of TIA attacks?waxing and waning course
While presenting symptoms may be similiar to those seen in TIA / CVA involving other vascular territories, the primary area supplied by the basilar artery is the _______?pons
List 6 s/s of pontine ischemia?1) alteration in level of consciousness, coma 2) transient or persistent asymmetrical paresis 3) adventitious muscular movements such as fasciculations and jerking 4) ataxia that is usually bilateral but asymmetrical 5) oculomotor abnormalities 6) facial weakness, dysphonia, dysarthria, dysphagia, limited jaw movement
List the differential dx for basilar artery occlusion?1) basilar migraine 2) basilar meningitis 3) cerebellar hemorrhage 4) cerebellar infarct 5) brain tumors
If basilar artery occlusion is suspected, rapid _____ is mandatory?imaging
Which imaging modalitiy is highly sensitive for identifying hemorrhage within the first 24 hours; however, it has a low sensitivity for early ischemia and bony artifact may limit the images of the brainstem and cerebellum?CT scan
Which imaging modality is much more sensitive for detecting early ischemia (but it is expensive and less available) and requires a longer period of time for the scan?MRI
Does US have a place in the acute imaging of the basilar artery systemt?no
Patients with suspected basilar artery occlusion should be rapidly _______? How so?stablized (airway, breathing, circulation)
What BP parameters guide treatment of blood pressure in basilar artery occlusion?treated if >220 mmHG systolic OR > 120 mmHg diastolic (to reduce risk of hemorrhage while also maintaining cerebral perfusion)
If thrombolysis is considered, what is the BP goal?< 185/110 mm HG
List the antihypertensive agents of choice?1) nicardipine (Cardene) 2) labetalol (Trandate)
What treatment is presumed to be the key determinant of long-term prognosis?recanalization of the basilar artery
What isseus need clarification about recanalization?1) preferred method (intra-arterial thrombolysis, mechanical thrombolysis or a combination) 2) patient selection (severity of stroke, age, comorbid conditions such as uncontrolled DM, anticoagulation) 3) ideal time frame for treatment
The ____ of the thrmbus is related to the success of recanalization?length
*** In one study of patients undergoing intravenous plasminogen activator treatment, thrombi < _____ mm had a 70-80% success rate, while thrombi > ____ mm only were succesfully recanalized in 20-30% of cases?10; 30
Currently, the only agent approved by the FDA is what? Which must be administered within ____ hours of the onset of symptoms if the IV route is used?1) tissue plasminogen activator (tPA) 2) 3
Are there any randomized controlled trials to gauge the relative effectiveness of intra-arterial thrombolysis compared to IV treatment?no
The rate of complications associated with intra-arterial thrombolysis in these case series is comparable to the rate seen with ____ tPA?IV
Intra-arterial thrombolysis is typically administered in context of a clinical trial, and most protocols allow for administration up to ____ hours after the onset of symptoms?12
*** Comment on the ENDSTROKE study?there was no link found between recanalization and clinical outcomes, but the heterogeneity of the patients and treatment protocols made it difficult to interpret the results and draw meaningful conclusions
If thrombolytic therapy is anticipated, what treatment should be avoided in the acute setting due to an increased risk of bleeding?anticoagulation
Comment on warfarin?it seem to be somewhat better than ASA in preventing strokes in patients with intracranial stenosis, but complications (bleeding) lessened the impact of this difference
Are there studies existing regarding the preventive benefits of newer antiplatelet agents?no
*** SUMMARY = Are the risk factors for basilar artery occlusion the same as CVA?yes
*** SUMMARY = Basilar artery occlusion is more common in what gender, what age group and what ethnic group?men; elderly; African Americans
*** SUMMARY = Is the morality rate of acute, untreated basilar artery occlusion very high?yes
List the s/s of basilar artery occlusion?1) alteration in consciousness 2) asymmetrical paresis 3) oculomotor abnormalities 4) adventitious muscular movements 5) bilateral but asymmetric ataxia