Pathophysiology - Haemorrhagic
- Atheroembolic
- Cardioembolic
- Infectious
- Cerebral Vasculitis
- Cryptogenic
Clinical Presentations - Left Hemisphere (dominant)
- Right Hemisphere (non-dominant)
- Cortical and Subcortical
- Lacunar Syndromes
- Pure Motore Hemiparesis
- Pure Sensory Stroke
- Dysarthria - Clumpsy Hand Syndrome
- Homolateral Ataxia and Cural Paresis
- Isolated Motor / Sensory Stroke
Imaging Study
CT Perfusion Imaging - Blood Flow
- Blood Volume
- Together helps decide if there is any tissue to salvage
- Sustained blood flow < 10-12 ml / 100 gm / min leads to rapid cell death (<30 min) . k/a Ischemic Core or Irreversible Infarct
- 12-20 ml /100 gm / min : Pneumbra - potentially salvageable area
- Ideal Imaging Study
- Rapid
- Differntiate from infarted vs salvageable tissue
- Location of clot, and nature of clot (hard calcified vs soft)
- NCCT: For screening ICH
- Early ischemic changes in baseline CT was not a factor
- MRI is as effective as CT at identifying hyper acute ICH (<12 hr)
- Hypodentisty
- Loss of grey-white matter differentiation (early sign of ischemia and edema)
- Disappreace of insular ribbon
- loss of distinction of lentiform nucleus
- Sulcal effacement
- Studies related to NCCT
- ECASS - 1
- IV - tPA
- Dense artery sign
- increased density within a vessel lumen
- Classically seen in MC or BA
- > 8 mm means IV tPA may not be enough
- ASPECTS Score (0-10, less the number worse the score)
- Topographic scoring system
- Based on functional importance, not size
- Internal Capsule, Basal Ganglia Caudate (are small areas but important areas functionally)
- Divides MCA territory into 10 areas
- Advantages:
- Disadvantages
- CTA
- Small amount of study
- Generally does not cause worsening of renal function
- Done same time as NCCT
- Advantage:
- Disadvantage:
- Physiologic Imaging
- Search for penumbra
- MR perfusion/diffusion or CT Perfusion imagine is used
- MR Diffusion
- Diffusion of water across the cells of membrane in severely damage tissue is measured
- Diffusion restricted in irreversible cell damage
- Some studies have shown there can be "reversible" DWI
- MR perfusion
- Studies
- DIFFUSE
- Perfusion - Diffusion mismatch
- EPITHET (rtPA vs placebo)
- CT Perfusion
- obtained along with CTA
- measure the first pass flow
- Physiology of CT Perfusion (different from MR Perfusion)
- Cerebral blood volume is identified
- pCBF (blood flow) and rCBV (blood volume)
- Studies
- Sensitivity of 80 % and specificity of 95 % for diagnosis of acute ischemic stroke
- Imaging of collaterals
- Leptomenigeal collaterals play an important role in maintaining the flow to an ischemic area
- Studies
Treatment of Stroke: 2 Goal- Initial golden hours: TIME = BRAIN
- Goal: Prevent further damage of the brain
- Endovascular Therapy for Stroke — It’s about Time NEJM Editorial 2015 (MUST READ to understand Endovascular Therapy Trials)
- NNT for outcome benefit with endovascular therapy is between 3-7 patients
- tPA within 3 hr
- tPA within 6 hr with mechanical thrombectomy
- tPA + Stent retriever thrombectomy within 6 hr
- Mechanical thrombectomy within 8 hr after tPA or tPA ineligible patients
- Addtional studies published in 2015
- The Extending the Time for Thrombolysis in Emeragency DeficitsIntra-Arterial (EXTEND-IA)
trial
- The Endovascular Treatment for Small Core
and Anterior Circulation Proximal Occlusion with
Emphasis on Minimizing CT to Recanalization
Times (ESCAPE) trial
- Monitor for complications
- After initial golden hours
- Rehabilitation
- Secondary Stroke Prevention: Based on Mechanism
Mechanism of Stroke: Clinical Cues to suggest the etiology of Stroke Cryptogenic Stroke NEJM 2016
Supplement to: Saver JL. Cryptogenic stroke. N Engl J Med 2016- Atheroembolic
- HTN control
- Hyperlipidemia
- Anit-platelet (see separate page for this)
- Based on SAMPRISS study, one can use combination of ASA + Clopidogrel for Intracranial stenosis for upto 3 months after considering the risks and benefit
- SAMMPRIS NEJM 2011
- Surgical Intervention for Carotid Stenosis
- Severe stenosis can cause "watershed infarct"
- CEA
- Stenosis of 70% or more, the 2-year risk of
ipsilateral stroke was 9% in the group of CEA plus
medical therapy versus 26% in medical therapy alone (P<0.001).
- The 5-year risks
were 15.7% in the endarterectomy group versus
22.2% in the medical-therapy group (P=0.04)
among patients with stenosis of 50 to 69%.
- There
was no benefit of carotid endarterectomy in patients with stenosis of less than 50%.
- Among all
patients who were randomly assigned to carotid
endarterectomy, perioperative strokes occurred
in 5.5% (nondisabling in 3.7% and disabling in
1.8%), death in 1.1%, and wound hematoma in
5.5%.
- NASCET (Carotid Endarterectomy in Symptomatic Patients NEJM 1991
Role of carotid Stenting
- Very small role. Its role is narrowing even further.
- Symptomatic Patient will benefit. Who are symptomatic patients.
- Amaurosis Fugax (has to be ipislateral symptoms of the same side of stenosis)
- TIA
- Focal ischemia resulting in a NON-disabling Stroke (modifeid RANKIN <3)
- (EXCLUDED ARE: Modified RANKIN score > or equal to 3)
- Also, note:: 25-40 % events were not related to carotid stenosis.
- High risk surgical candidate (were exclusion criterias of clinical trials)
- NYHA III-IV
- EF <30
- Angina III -IV
- Contra lateral occlusion
- MI within 6 weeks
- Re-steonosis of CEA
- Radiation induced stenosis.
- Reference:
- Cardioembolic
- Anti-coagulation
- References:
- Cryptogenic Stroke
- Recurrent stroke:
- Cardiac monitoring
- High dose statin - LDL control, BP control
 - PFO Closure
- Infectious Cause of Stroke
- Carotid Artery Dissection
- More common in younger age group
- Usually occurs 2 cm distal to bifurcation
- Often spontaneous; may be related to trauma by transverse process of C2, C3
- Considerable ipsilateral neck, face and head pain is common in around 60% of patients
- Horner syndrome may occur due to injury to sympathetic nerve at arterial wall
- Extracranial ACUTE dissection - anti-coat for 3-6 months
- Haemorrhagic Stroke
- Fibromuscular Dysplasia
- Associated with intramusclar aneurysms and carotid dissections
- ASA for stroke prevention
- Cerebral Vasculitis
- Additional References
- Goals of Management
- Secondary Stroke Prevention (as above in Stroke)
Atherosclerotic Diesease
Additional Reading Materials
http://img.medscapestatic.com/pi/meds/ckb/84/7084.jpg
Appreciate Carotid Artery Disease causes approximately 20 % of the stroke. N Engl J Med 2013;369:1736-48.
 N Engl J Med 2012;367:1450-60
N Engl J Med 2013;369:1736-48.
N Engl J Med 2013;369:1736-48.
Stroke Additional Literature
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N Engl J Med 2012;367:1450-60
