A Trial of Adacolumn on Cerebral Edema After Anterior Circulation Ischemic Stroke

Inclusion Criteria: 1. Age 18-80 years, regardless of gender; 2. A clinical diagnosis of acute ischemic stroke; 3. Proven large vessel occlusion in ICA or MCA-M1 occlusion (carotid occlusions can be cervical or intracranial, with or without tandem MCA lesions) determined by MRA or CTA or DSA; 4. NIHSS score ≥10 at screening; 5. Pre-stroke mRS score \<2 (independent in all activities of daily living); 6. Time from stroke onset to initiation of the first Adacolumn treatment is ≤24 hours, stroke onset is defined as the last time the patient was known to be at their neurological baseline (wake-up strokes qualify if within this time window); 7. All endovascular thrombectomy and/or intravenous thrombolysis must strictly adhere to the "2024 Chinese Stroke Association Guidelines for Reperfusion Therapy in Acute Ischemic Stroke" and the latest prescribing information regarding indications, contraindications, and procedural standards; 8. Written informed consent obtained from the patient or legally authorized representative. Exclusion Criteria: 1. Decompressive craniectomy performed before enrollment or between enrollment and initiation of study treatment; 2. After endovascular thrombectomy: extensive contrast extravasation (diffuse subarachnoid high density or parenchymal high density not consistent with hematoma), new subarachnoid hemorrhage（SAH）, or symptomatic intracranial hemorrhage (sICH); 3. Large-vessel occlusion is attributed to other determined etiologies per TOAST classification, such as tumor-related, dissection-related, or other clearly identifiable non-LAA/non-CE causes. 4. Clinical signs of brain herniation, such as unilateral or bilateral fixed dilated pupils and/or other loss of brainstem reflexes attributable to cerebral edema or herniation in the investigator's opinion; 5. Intracranial lesions conferring markedly increased bleeding risk (known brain tumor, arteriovenous malformation, aneurysm); 6. Inability to undergo MRI; 7. Absolute neutrophil count \<1.5×10⁹/L or \>15×10⁹/L 8. Absolute monocyte count \> 1.0 ×10⁹/L; 9. Red blood cells \<3.0×10¹²/L ; 10. Active internal bleeding or bleeding tendency (such as platelet count \<100×10⁹/L, INR \>1.7, PT \>15 seconds); 11. Marked hypercoagulability (fibrinogen \>700 mg/dL); 12. Intracranial or spinal surgery or severe head trauma within the past 3 months; 13. Refractory hypertension (persistent systolic blood pressure \>185 mmHg or diastolic \>110 mmHg); 14. Known allergy to components of the blood purification system (including adsorption membrane, anticoagulants); 15. Acute ST-segment elevation myocardial infarction and/or acute decompensated heart failure and/or corrected QT interval \>520 ms and/or history of cardiac arrest within the past 6 months(pulseless electrical activity, ventricular tachycardia, ventricular fibrillation, or asystole); 16. Body temperature \>38°C or active infection; 17. Active autoimmune disease or immunodeficiency; 18. Participation in another interventional clinical trial within the past 30 days; 19. Any other condition deemed unsuitable for participation by the investigator.