Mechanical Thrombectomy of Medium Sized Vessels "M2 of MCA".

Mechanical Thrombectomy of Medium Sized Vessels "M2 of MCA" :a Clinical Trial

Mechanical thrombectomy recently has revolutionized the treatment of stroke. Trials have demonstrated the superiority of mechanical thrombectomy in large vessel occlusions, such as in the intracranialinternal carotid artery and proximal, middle cerebral artery (M1), middle cerebral artery trunk (M1), have relatively high rates of revascularization and favorable clinical outcomes after MT. , However second-order branches of the middle cerebral artery (M2) occlusions (postbifurcation in the Sylvian fissure) were underrepresented or not represented in the trials. Posing a more significant technical challenge to the available endovascular devices because of the smaller size and tortuosity of these arteries and the greater likelihood of recanalization with intravenous thrombolysis, the overall risk-benefit remains uncertain.

this study aims to:

1. compare efficacy of mechanical thrombectomy over medical treatment in occlusion of M2 division of MCA.
2. improve outcome of acute ischemic stroke.

The study will include all patients with AIS attending to emergency deparment with proven occlusion of M2 division of MCA, and deviding then into 2 groups:

Group 1 will receive medical treatment (rTPA if presented in the first 4 hours, and antiplatelet if passed time window for IVT) Group 2 will underwent mechanical thrombectomy (if accessible), and even after receiving medical treatment and not improved and comparing the outcomes of these 2 groups

c. Sample Size Calculation: Sample size was calculated using G*power, version 3.1.9.7. Estimation based on results of previous study which reported that, median (IQR) discharge NIHSS in mechanical thrombectomy group was 2 (0-4) compared to 1 (0-2) in medical management group giving medium effect size . With a power of 80% (using one-sided t-test, effect size = 0.65 and α of 0.5) the sample needed for the study was estimated to be 60 patients (30 in each group).

Study design:

All patients are subjected to the following: -

• Enrolled patients were admitted to stroke units or intensive care units.
• Intravenous t-PA was allowed if begun within < 4.5 hours after symptom onset.
• Thrombectomy will be performed with any FDA approved thrombectomy device by the use of local anesthesia (general anesthesia will be discouraged).

Imaging

• Patients presented with clinical picture and radiography suggestive of large vessel occlusion and who meet the proposed clinical criteria for EVT will be subjected to a comprehensive evaluation with:
• Arterial imaging of the cerebral circulation with preferably with CTA or alternatively with magnetic resonance angiography to
• Perfusion imaging with perfusion CT or with diffusion weighted imaging MRI can allow identification and quantification of the ischemic penumbra and, therefore, is useful for assessing patient eligibility for EVT in the extended time window.

Inclusion Criteria:

• Age >18 years
• Cerebral infarction in anterior circulation involving occlusion of M2 MCA, proven by CTA
• With or without IV thrombolysis
• Access to endovascular treatment within 24 hours from onset.

Exclusion Criteria:

1. Proven proximal occlusion of MCA.
2. Disability prior to the stroke (mRS >3)
3. Opposition of the patient or their family