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53 Cards in this Set
- Front
- Back
What are the 5 main territories of brain blood supply? |
ACA MCA PCA Lentoculostriate Anterior choroidal artery |
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What are the common causes of ischemia at water shed areas ? Adults 2 Kids 1 |
Severe carotid stenosis Severe hypotension Moyamoya disease ( idiopathic supraclinoid vaso-occlusove disease) |
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4 classical signs of ischemic stroke in head ct? |
Dense MCA sign Loss of insular ribbon sign Loss of grey-white matter differentiation Mass effect ( 3-5 days) |
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Fogging phenomenon happened at which date of stroke in CT and in T2 |
CT 14 days T2 10 days |
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Findings Diagnosis |
Bilateral hypodense aspect of the medial thalamus, suggesting subacute ischemia caused by occlusion of the artery of Percheron. No signs of cerebral venous thrombosis. No dense aspect of the basilar artery. Artery of Percheron stroke |
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What is artery of Percheron? |
It is a normal anatomical variant Common trunk that supplies the thalami and rostral midbrain that is arising from PCA. Normally there are multiple branches. |
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Finding Diagnosis |
Focal hypodensity involving the right caudate head and anterior limb of the internal capsule. Recurrent artery of Heubner infarction |
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What is recurrent artery of Heubner ? When it can get injured ? What area get infarcted? |
Is a deep branch of the proximal ACA. Clipping of ACOM aneurysm Caudate nucleus |
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What is cardioemboloc stroke ? MRI appearance |
A fib or endocarditis showering thrombi Diffusion restriction at multiple areas |
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Findings Diagnosis |
Diffusion restriction at the left MCA and left PCA territories Fetal PCOM stroke |
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What is fetal PCOM ? |
PCA get feeding directly from ICA Mixed pattern of MCA and PCA territory infarction |
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Restricted diffusion in ischemic stroke seen between ----- to ----- time |
30 minutes to 2 weeks |
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If a stroke patient shows diffusion restriction with normal T2 this is probably? |
Hyperacute stroke <6hours |
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Hemorrhagic transformation happened between --- hours to ---- days |
6 hours 4 days |
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Predictors of hemorrhagic transformation? 5 |
Multiple infarcts Delayed >6hrs recanalisation > 1/3 of MCA is infarcted Proximal MCA infarction Absent collateral flow |
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Risk factors of venous infarction? 3 |
Infants Dehydration Older kids mastoiditis Adults coagulopathy ( protein c and S deficiency) and oral contraceptive pills |
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Commonest location for venous infarct? |
Superior sagittal sinus |
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CT findings of venous sinus thrombosis ? |
Non contrast hyperdense Empty delta sign on contrast |
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Differences BTW arterial and venous stroke? |
Arterial cytotoxic edema Venous both cytotoxic and vasogenic |
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What happened in chronic venous thrombosis ? 2 |
Development of dural AVF Increased CSF pressure from impaired drainage |
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What is ASPECTS score ? Drawback is ? |
Alberta stroke program early CT score It is used for giving TPA Only for MCA infarcts |
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ASPECTs score favouring TPA Not favouring TPA? |
Above 8 is good Score of 7 or less is not worth TPA |
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Who gets aneurysm? 6 |
Polycystic kidney disease Smokers Connective tissue disease( Marfan and Ehler danlos) Aortic Coarctation AVMs NF FMD |
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Aneurysm Where do they occur? Commonest site? Second common site ? |
At branching point Anterior circulation ACA Posterior circulation ( basilar artery then origin of PICA) |
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Why do persistent trigeminals get more aneurysm? |
They have more branch points |
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Finding |
Large persistent trigeminal artery passing from the left ICA to the terminal basilar artery via the cavernous sinus. Note the grossly hypoplastic vertebro-basilar arterial system as a result of this congenital anomaly with most posterior circulation blood coming from the left ICA via the trigeminal artery. |
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Risk of aneurysm rupture?5 |
Size .posterior location. Female Smoking Hx of previous SAH |
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Finding Diagnosis |
CT angiogram reveals a dolichoectatic basilar artery occupying the left cerebellopontine angle, which bifurcates at the level of the third ventricle. Dolichoecrasia of basilar artery |
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How you assess severity of dolichoectasia? Complications? 4 |
Height and lateralisation of the basilar artery Dissection Compression of cranial nerves Brainstem stroke Hydrocephalus |
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Commonest type of aneurysm? |
Saccular aneurysm at bifurcation or branch points |
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Mention types of aneurysm? 5 |
Saccular Fusiform Blister Pedicle Mycotic |
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Fusiform aneurysm associated with ? 3 Common site ? Mimic ? |
Syphilis PAN Connective tissue disease Posterior circulation CPA tumor |
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When to suspect pseudoaneurysm? Causes? 2 |
Atypical location Focal hematoma next to it Traumatic Mycotic ( MCA ) endocarditis, meningitis, thrombophlebitis |
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What type of aneurysm is sneaky and often have negative CTA ? Commonest site? |
Blister aneurysm ICA ( supraclinoidal segment) |
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What is infundibular widening ? |
Not a true aneurysm but it is funneling of PCA origin no more than 3 mm |
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What you aneurysm associated with AVM? Where it is found? |
Pedicle aneurysm In the artery feeding AVM They have higher risk to bleed than aneurysm themselves |
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What is the treatment cut off of anterior circulation aneurysm? |
7 mm |
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Maximum bleeding site according to aneurysm location? ACOM PCOM MCA trifurcation Basilar tip PICA |
ACOM interhemispheric fissure PCOM ipsilateral basal cisterns MCA trifurcation sylvian fissure Basilar tip interpeduncular cistern interaventricular PICA posterior fossa or intraventricular |
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What are the vascular malformations ? 5 |
High flow AVM Dural AVF Low flow Dural AVF DVA Cavernoma ( cavernous malformation) Capillary telengiectasia |
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Most common type of high flow vascular malformation? Common location ? Most common complication? |
AVM Supratentorial Bleeding 3% every year |
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What are the risk factors for AVM to bleed ? 4 Clinical presentation? 2 |
Small AVM ( high pressure) Small draining vein( bo pressure relief) Peri- nidal aneurysm Basal ganglia location Headache and seizure |
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Finding Diagnosis |
MIP CTA confirms the presence of a left temporal lobe arteriovenous malformation (AVM) which appears to receive the vast majority of its supply from the left middle cerebral artery. Contribution from the posterior cerebral artery is although likely via the lateral posterior choroidal arteries. Contribution from anterior cerebral artery and meningeal arteries cannot be excluded. Drainage appears to be predominantly superficial, over the temporal lobe and into the transverse / sigmoid sinus. The superior petrosal sinus appears plump and likely also provides some drainage. Fig 1: nidus (blue arrows) and enlarged middle cerebral arteries (orange arrows).Fig 2: draining veins (blue arrows)Fig 3: enlarged posterior cerebral artery (blue arrow) with likely contribution via the lateral posterior choroidal arteries. Small branches can be seen extending from the choroid plexus to the nidus (orange arrow). |
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Dural AVF Most common type? Classic history? Is it congenital or acquired |
Spinal dural AVF Progressive lower extremity weakness with sphincter dysfunction They might have unexplained SAH Usually acquired |
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Complications from spinal dural AVF? How they are acquired? |
Ischemia and infarction From recanalisation of previous dural sinus thrombosis |
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Finding Diagnosis |
The lower half of the thoracic cord demonstrates extensive central cord high T2 signal. On the dorsal surface of the cord numerous flow voids are noted. |
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In spinal dural AVF, what is the next step? Why? |
Conventional angiography To detect other fistula and usually the fistula is at different site than the images |
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Finding |
Developmental venous anomalies and cavernous malformations frequently co-exist as in this case. |
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DVA is Associated with ? |
Cavernomas |
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How DVA appears in MRA? |
Caput medusa Collection of vessels converging toward an enlarged vein ( seen only in venous phase) |
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What is cavernoma?2 Risk factor? Appearance? |
Low flow vascular malformation Without intervening tissue Radiotherapy Popcorn like with peripheral hemosiderin |
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Best sequence to look for cavernoma? Associated with ? Complication? |
Gradient DVA It may ooz but no significant bleeding May have fluid fluid levels |
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Finding Diagnosis |
There is an area of signal abnormality in the anterior aspect of the pons, which crosses the midline and is not associated with any mass effect. It is slightly hyperintense on T2 weighted images, and isointense on T1. Following administration of contrast it demonstrates an ill-defined blush of contrast. Susceptibility weighted imaging demonstrate signal drop out. Capillary telengiectasia |
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What is capillary telengiectasia?2 Risk factor? Classical appearance? |
Low flow vascular malformation With intervening normal tissue Radiotherapy Single lesion in the pons |