Vessel Wall Imaging of Intracranial Arterial Disease Commercial Interests

Transcription

1 Vessel Wall Imaging of Intracranial Arterial Disease Commercial Interests Disclosures No relevant commercial interests Off Label / Investigational Use No off label / investigational use Daniel Mandell, MD PhD FRCPC University Health Network University of Toronto Objectives: 1. How? 2. Why? 3. What can go wrong? Black Blood and Cerebrospinal Fluid High Spatial Resolution Routine contrast-enhanced -weighted spin echo Sequence optimized for vessel wall imaging (IR-prep spin echo) 2D -weighted FLAIR 0.4 x 0.4 x 2.0 mm voxel 3D PD-weighted SPACE 0.5 x 0.5 x 0.5 mm voxel size 1

2 High Spatial Resolution High Spatial Resolution 2D -weighted FLAIR 0.4 x 0.4 x 2.0 mm voxel 3D PD-weighted SPACE 0.5 x 0.5 x 0.5 mm voxel size 2D -weighted FLAIR 0.4 x 0.4 x 2.0 mm voxel 3D PD-weighted SPACE 0.5 x 0.5 x 0.5 mm voxel size Reason #1 to do wall imaging: Infections Dissection PRES Primary Vasculitis of CNS? Drugs Systemic infection with autoimmunemediated CNS vasculitis Systemic vasculitis with CNS involvement Atherosclerosis Neoplastic Radiation arteriopathy CADASIL Moyamoya Normal 2

3 Vasculitis Dissection Atherosclerotic Plaque Normal Normal 3

4 Vasculitis gad gad Dissection no gad Normal for comparison Atherosclerotic Plaque Atherosclerotic Plaque Adventitia Lipid core Fibrous cap 4

5 Reason #2 to do wall imaging: 63 F with acute right-sided hemiparesis About 25% of strokes are cryptogenic after standard work-up 1 : History, physical exam CBC, INR, PTT MRI or CT brain MRA or CTA head and neck Echocardiography 24 hour cardiac rhythm monitoring 63 F with acute right-sided hemiparesis 63 F with acute right-sided hemiparesis 63 F with acute right-sided hemiparesis 63 F with acute right-sided hemiparesis 5

6 Reason #3 to do wall imaging: Assess Disease Activity Why is it useful to diagnose this? 1. Avoid expense, discomfort, morbidity of looking for other causes e.g. Prolonged cardiac rhythm monitoring e.g. Cerebrospinal fluid sampling e.g. Brain biopsy for?vasculitis 2. Avoid misdiagnosis of stroke etiology e.g. Patent foramen ovale in 50% of cryptogenic stroke patients but also in 25% of general population e.g. Transient arrhythmia on prolonged monitoring is not 63 necessarily F with acute the cause right-sided of stroke hemiparesis GAD Initial GAD 6 months later Reason #3 to do wall imaging: Assess Disease Activity Reason #3 to do wall imaging: Assess Disease Activity no gad no gad no gad no gad Unruptured Aneurysm Ruptured Aneurysm 6

7 Reason #4 to do wall imaging: Reason #4 to do wall imaging: Reason #4 to do wall imaging: Looking ahead Can we risk-stratify unruptured aneurysms? LOOKING AHEAD Standard vessel wall MRI sequence Work-in-progress sequence optimized for blood suppression Can we identify high-risk components of AVMs? SUMMARY Vessel wall MRI is likely useful to: Differentiate among causes of narrowing Identify symptomatic disease which is occult on CTA/MRA/DSA Vessel wall MRI is possibly useful to: Assess arterial disease activity Determine which aneurysm has ruptured in patients with multiple aneurysms Vessel wall MRI is in domain of research to: Predict future rupture risk of aneurysm 7