Intra-arterial Tenecteplase for Acute Medium Vessel Occlusion Stroke

Inclusion Criteria: Clinical Inclusion Criteria: 1. Age ≥18 years; 2. Pre-stroke mRS 0-1; 3. Within 24 h from symptom onset; 4. Baseline National Institutes of Health Stroke Scale (NIHSS) score \>5 or baseline NIHSS 3-5 with disabling deficit (e.g., loss of hand function, aphasia, hemianopia); 5. Informed consent obtained from patients or their legal representatives. Imaging Inclusion Criteria: 1. Baseline CTA/MRA/DSA diagnosed isolated MeVO, referring to the M2/M3 segment of the MCA, the A1/A2/A3 segment of the ACA, the P1/P2/P3 segment of the PCA; 2. NCCT or MRI DWI imaging showing that the territory of the ischemic infarct volume is less than 50% of the estimated territory supplied by the occluded artery. Exclusion Criteria: 1. Acute intracranial hemorrhage; 2. ASPECT ≤5; 3. MeVO secondary to spontaneous fragmentation and distal migration of thrombus from an acute large vessel occlusion, or occurring after intravenous thrombolysis (IVT), intra-arterial thrombolysis, or endovascular thrombectomy; 4. Contraindication to TNK; 5. Known severe allergy to contrast agents (excluding mild rash-type allergic reactions); 6. Use of heparin or novel oral anticoagulants within the previous 48 hours with an INR ≥ 1.7; 7. A history of major bleeding within the past 6 months or the presence of conditions such as active gastrointestinal ulcer, aortic dissection, platelet count \< 100 × 10⁹/L, etc.; 8. Radiologically confirmed vascular malformations, arterial dissection, intracranial aneurysm (diameter≥3 mm), tumors (except small meningiomas), cerebral vasculitis, cerebral amyloid angiopathy, or other major non-ischemic intracranial diseases (e.g., multiple sclerosis); 9. Acute renal failure, current dialysis, or estimated glomerular filtration rate (eGFR)\<30ml/min/1.72m2, and/or serum creatinine\>220mmol/L (2.5mg/dl); 10. History of severe liver disease, or aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) and/or glutamyl transferase (GGT) ≥3×upper limit of normal value (ULN) and/or total bilirubin (TBIL) ≥2×ULN; 11. Severe non-cardiovascular comorbidity with an expected life expectancy of less than 3 months (e.g., malignant tumors); 12. Known pregnancy or breastfeeding, or a positive pregnancy test prior to randomization; 13. Current participation in another drug or device clinical trial; 14. Any other condition deemed by the investigator to make the patient unsuitable for participation in the study or to pose a significant risk to the patient (e.g., inability to understand and/or comply with study procedures and/or follow-up due to psychiatric illness, cognitive impairment, or emotional disorders).