Very late stroke - SLICE Worldwide 2021 - Claude CALIPO

Very late stroke + prehospital management issues

Presentation of case resolution in the form of a “serious game”.  Misdiagnosed and very late double M2-MCA stroke with severe symptoms in a young patient. Video covers some interesting topics: 

- artificial intelligence applications improving diagnosis

- which one of the M2 branches should be treated and how

- ICA dissection management

- outcome predictors supporting the decision-making process whether to treat or not. 

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Stroke Misdiagnosis:

Stroke mimic and initial manifestation of stroke as seizure prevalence - in publications:

• seizure mimicking stroke - 4%
• acute stroke manifesting as seizure – 0.6% 

Highlight*:  CVAID AI-based platform for stroke management (from early detection to follow-up)

1. simple to use everywhere
2. allows precise detection by measuring and processing micro movements and voice
3. dramatically shortens time to treatment
4. improves clinical results

The important role of check-list approach to avoid misdiagnosis and omission of stroke:

Regarding CT:

• dense vessel sign
• loss of Insular ribbon 
• loss of lentiform/nuclear/cortical differentiation
• hypodensities

Highlight*: Methinks - AI-based application detecting ischemic stroke in imaging findings 

1. allows to detect and score ischemic stroke extent even in non-contrast CT (ASPECT scale scoring)
2. detect the side and the level of the occlusion even in non-contrast CT

Late Stroke:

Beyond 8 hours of stroke onset you should use advance imaging and/or clinical-radiological mismatch to qualify patient for thrombectomy.

If cortical areas are preserved despite the hypodensities in white matter, it may be worth performing thrombectomy, especially if the patient is young and there is clinical-radiological mismatch.

It is possible to extend the window for IVT based on EXTEND trial! (decision based on advance imaging modalities CTP and PWI MRI).

ASPECT scale has a lot of imperfections:

• based only on the extent of the lesions
• does not differentiate the eloquence of the regions

Much better is clinical and profound imaging evaluation of the patient:

• does the patient have dense plegia?
• is modal cortex viable?
• is corona radiata viable?

If the answers above are YES = there is clinical-radiological mismatch à go to the angio!

Distal MCA Stroke in 10 rules:

1.Beyond the M1 occlusion it is worth analyzing the occlusion and its impact on multimodality viewer with coronal and MIP reconstructions.

2. If the clots are located in two M2 MCA branches:

1. evaluate the level of occlusion: more proximal would be easier to go and would carry less risk of hemorrhage than distal
2. evaluate the size of the branches: bigger usually would be more important and easier to attempt
3. evaluate the functional importance: inferior branch usually vascularizes posterior part of MCA territory and is more important functionally  BUT
4. take into consideration the viability of the regions: go for branches vascularizing viable regions, do not treat the arteries feeding irreversibly injured regions 
5. evaluate the type of the technique  

For  inferior trunk (bigger, straighter) à combined technique with stent-retrievers

3. If the occlusion is distal it is worth considering  general anesthesia: 

May improve the visibility due to reduction of the patient’s movement

 4. You should always go with the smallest microcatheter that is possible to effectively treat the lesion:

Easier to pass the thrombus

Less risk of clot migration while passing the lesion

5. Try to go as distal as possible with your microcatheter (before the next curve).

 6. Consider using i.a thrombolysis for distal occlusion and tortuous vessels.

 7. Combined technique improves the safety and reduces the amount of vascular injury when used with stent-retrievers placed distally: 

It optimizes the force vector and decreases the vessel’s retraction.

 8. To deliver the aspiration catheter to its desired position when performing distal thrombectomy, you can first pass with microcatheter, deploy SR within the clot and then use the SR as an anchor to make the exchange over its wire and pull in the aspiration catheter.

 9. If you have difficulties to pass the thrombus you are maybe dealing with fibrine-rich clot and contact aspiration alone instead of combine technique may be reasonable.

 10. To decide if it is necessary to reopen 2nd branch, you can combine the defect of parenchymal filling in your post-recanalization control DSA with NECT or perfusion CT to evaluate its viability and eloquence. You can also do the CBCT in angio-suite (contrast staining is a bad sign – already established infarct). 

Small SRs: 

1. Catch Mini
2. Preset Lite
3. Eric
4. Trevo, Solitare 3 mm

ICA Dissection:

Cervical loop is a risk factor for dissection.

Dissection – approaches:

• You can keep the BCG below the dissection because of its large lumen 
• You can cross the lesion of the dissection and place your sheath or aspiration catheter above the dissection to “work” above and do not have to pass every time the lesion all over again
• For example when having the M2 occlusion you can do SOLUMBRA technique with SR instead of SAFE technique, so you keep your aspiration catheter in M1 
• If after the pass there is occlusion of the extracranial part of carotid artery, go contralaterally to check whether you have managed to reopen the intracranial vessels and to evaluate the collateral circulation (contralateral femoral groin puncture if you want to keep your sheath in place)

     or

• You pass the dissection with microwire and microcatheter and do the run via microcatheter to check if you have managed to reopen the intracranial vessels (while preparing systems, you can give milrinone to the patient to eliminate potential vasospasm as a cause of extracranial occlusion)
• To stent or not to stent in the dissection:

It is not hemodynamic – it is worth not stenting, especially if there is some  established infarct and it is a late stroke

If it is hemodynamic – you should keep the ICA patent either with carotid stent or the flow-diverters depending of the level of dissection

Stenting in publications:

• Improve recanalization rates but did not change the clinical outcome
• Very few stroke recurrences under medical therapy (under 2%)

Outcome predictors:

Outcome is inversely proportional to: 

• Size of infarct
• Eloquent region’s involvment (especially superior-posterior areas M5-M6 and left M4)
• Biological age