Cervicocephalic Vascular Occlusion: Thinking Beyond Atherosclerosis Samuel I Frost DO, Yiping Li MD, Beverly Aagaard-Kienitz MD, Tabassum Kennedy MD 54th Annual Meeting of the American Society of Neuroradiology Abstract Number: eEdE-26

Disclosure The authors of this presentation have no financial disclosures to make All diagrams used in this exhibit were created by the authors

Objectives Brief review of cervicocephalic dissection including: Pathophysiology Demographics Imaging characteristics Treatment

Cervicocephalic Dissection Dissection: tear of the intimal vessel wall (yellow arrow) which allows flowing blood to penetrate into and delaminate the layers of the vessel wall. Dissecting aneurysm (pseudoaneurysm) Hematoma (white arrow) narrows and potentially occludes parent vessel lumen. Dissection with focal outpouching (black arrow)

Who Gets Dissection? All ages are affected 2.5-3 cases per 100,000 Mostly young and middle aged adults with peak age of 40 years Accounts for 10-25% of ischemic strokes in middle aged patients DSA 62 y/o female with spontaneous dissection of the V2 segment of the right vertebral artery. Note dissection flap (arrow)

Etiology Nontraumatic Iatrogenic Traumatic “Idiopathic” Vasculopathy Fibromuscular dysplasia Marfan Syndrome Ehlers-Danlos Type 4 Less common Hypertension Migraine headaches Physical activity Hyperhomocysteinuria Pharyngeal infection. Iatrogenic Endovascular interventions Traumatic Direct Indirect Iatrogenic internal carotid artery dissection after elective coil embolization of anterior choroidal artery aneurysm. Note dissection flap (curved arrow) and false lumen opacification (yellow arrow)

Internal carotid artery Location Dissections occur at the most mobile vessel segment Start or end in regions of transition from fixed to mobile Encasing bony canal, dural reflection Internal carotid artery Vertebral artery between skull base and C1 between C1 an C2 Spare the carotid bulb Usually stop at the skull base

Blunt Cerebrovascular Injury Grading Digital subtraction angiography Denver Criteria grade I : mild intimal injury or irregular intima. grade II : dissection with raised intimal flap / intramural hematoma with luminal narrowing > 25% / intraluminal thrombosis grade III : pseudoaneurysm grade IV : vessel occlusion / thrombosis grade V : vessel transection Grade I Grade II Grade III Grade IV Grade V

Flame shaped occlusion Dissection Imaging Optimal evaluation involves techniques that allow visualization of the vessel lumen CTA, MRA, Angiography Classic Signs CTA FS T1 MR CTA DSA Double lumen Eccentric thrombus Intimal flap Flame shaped occlusion Nonspecific signs Vessel occlusion Aneurysmal dilation Stenosis Double lumen and intimal flap are present in less than 10% of cases

Prognosis Disease progression 90% of non-occlusive stenosis resolve 60% of occlusions recanalize <5% of injuries lead to death Day 0 Day 3 Sequential TOF MRA studies demonstrating improved vessel patency in a 33 y/o female with spontaneous dissection of the V3 segment of the right vertebral artery (arrows) Day 21 Day 68

Case Examples

36 y/o female with headache, anisocoria, left hemiparesis and aphasia Dissection resulting in ischemic stroke 36 y/o female with headache, anisocoria, left hemiparesis and aphasia DWI CT T2 CT shows hyperdense thrombus within the right internal carotid artery (yellow arrow) with corresponding T2 hyperintense thrombus narrowing the vessel lumen (curved arrow) and right posterior middle cerebral artery territory infarct (white arrow)

51 y/o male with history of left sided numbness and weakness Vasculopathy associated dissection 51 y/o male with history of left sided numbness and weakness CTA CTA MIP CTA MIP CTA images of bilateral cervical internal carotid artery dissections with classic double lumen sign (yellow arrows) in the setting of fibromuscular dysplasia. Note the beaded appearance of the internal carotid arteries (white arrows)

Classic internal carotid artery location 50 y/o female with new onset facial droop and expressive aphasia CBV CTA CTA MTT CTA shows left internal carotid artery dissection extending from above the carotid bulb to the skull base (yellow arrows) with resultant left frontal lobe infarct (white arrow) and large area of ischemic penumbra (black arrows)

44 y/o female with left facial droop and left sided weakness Nonspecific signs of dissection 44 y/o female with left facial droop and left sided weakness MTT FS PD T2 CBV FS PD and T2 images show hyperintense circumferential thrombus narrowing the cervical left internal carotid artery and resulting in prolonged transit to left cerebral hemisphere with compensated cerebral blood volume. This is atypical of atherosclerotic disease in both location and configuration and is consistent with spontaneous dissection

44 y/o female with right arm numbness and tingling Nonspecific signs of dissection 44 y/o female with right arm numbness and tingling CBF CTA MTT DSA CTA shows nonspecific near occlusive stenosis of the cervical left internal carotid artery (yellow arrow) with associated prolonged transit and decreased cerebral blood flow. Digital subtraction angiography confirms vessel injury (white arrow) in the setting of fibromuscular dysplasia (curved arrow)

Posttraumatic intracranial dissection 11 y/o male presents after semi vs car moter vehicle accident CT CTA DSA Comminuted basisphenoid fracture involves the right carotid canal (yellow arrow). CTA and DSA show multiple traumatic pseudoaneurysms of the cavernous and supraclinoid internal carotid artery (white and black arrows)

Posttraumatic vertebral artery occlusion 53 y/o male presents after rollover motor vehicle accident CTA CTA CT CT CTA CT CT images show type II dens fracture (white arrows) as well as left C2 transverse process fracture which involves the foramen transversarium (black arrows). Sequential CTA images show complete occlusion of the distal V2 segment of the left vertebral artery (yellow arrows)

Treatment Treatment options Imaging surveillance Antiplatelet Anticoagulation Endovascular repair Open surgical repair Treatment is based on injury grade, presentation, comorbities and injury etiology Pre-Stent DSA Post-Stent DSA Endovascular stent repair (arrow) of a FMD associated dissection of the cervical left internal carotid artery

Treatment algorithm Injury Type Anticoagulation risk Recommended Treatment Grade I High Low None Antiplatelet II None vs delayed antiplatelet Antiplatelet +/- anticoagulation III Anticoagulation IV Endovascular embolization V Surgery vs endovascular repair

Endovascular treatment 40 y/o woman presents after motor vehicle accident Pre-stent DSA Pre-stent DSA CTA Post-stent DSA AP and lateral DSA images show long segment traumatic internal carotid artery dissection (white arrows) with focal pseudoaneurym (curved arrow) which is treated with multiple overlapping stents (yellow arrows)

Endovascular treatment 69 y/o women presents after motor vehicle accident 3D DSA Pre-stent DSA DSA image shows large post traumatic pseudoaneurysm of the cervical left internal carotid artery (white arrow) which was successful treated with flow diverting stent (yellow arrow). Immediate post stent 3D DSA reformat from shows stent in good position relative to pseudoaneurysm (curved arrow)

Summary Look for classic intimal flap and double lumen signs Additional clues: Eccentric thrombus, stenosis, occlusion or aneurysmal dilation Evaluate lesion location and adjacent vasculature Multiple sites, evidence of atherosclerotic disease or underlying vasculopathy? Consider patient presentation and history Spontaneous, traumatic and iatrogenic etiologies Age, gender, risk factors, and comorbities

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