Efficacy and Safety of Tenecteplase Intravenous Thrombolysis in Acute Posterior Circulation Ischemic Stroke Within 4.5-24 Hours After Onset

Inclusion Criteria: 1. Age ≥18 years. 2. Meeting at least one of the following criteria: acute posterior circulation ischemic stroke confirmed by MRI; symptomatic stenosis or occlusion of a posterior circulation large vessel on vascular imaging (CTA/MRA/DSA); perfusion imaging demonstrating clinically relevant hypoperfusion in the posterior circulation territory. 3. Onset time between 4.5-24 hours (for wake-up stroke or unwitnessed stroke, onset time is defined as the midpoint between last known well and symptom detection). 4. NIHSS score\>3. 5. PC-ASPECTS ≥7 (if discrepancy exists between DWI and CT findings, CT assessment takes precedence). 6. Pre-stroke mRS ≤1. 7. Signed informed consent by the patient or legally authorized representative. Exclusion Criteria: 1. Contraindication to tenecteplase or its components. 2. Planing to receive endovascular therapy with thrombectomy, angioplasty or stenting whin 3 months. 3. Acute anterior circulation infarction confirmed by MRI, anterior circulation large vessel occlusion on vascular imaging (CTA/MRA/DSA), or anterior circulation hypoperfusion on perfusion imaging. 4. History of intracranial hemorrhage. 5. Stroke, myocardial infarction, severe traumatic brain injury, or intracranial/spinal surgery within the preceding 3 months. 6. Intracranial tumor, arteriovenous malformation (AVM), or giant aneurysm. 7. Active internal bleeding, major surgery, trauma, gastrointestinal/urinary tract bleeding within 3 weeks. 8. Non-compressible arterial puncture within 1 week. 9. Suspected aortic dissection. 10. Clinically significant bleeding or coagulopathy, including: Warfarin use with INR \>1.7 or PT \>15 s; Low-molecular-weight heparin within 24 hours; Direct oral anticoagulants within 48 hours; Laboratory abnormalities (e.g., APTT \>40 s). 11. Platelet dysfunction or platelet count \<100×10⁹/L. 12. Uncontrolled hypertension (systolic BP \>180 mmHg or diastolic BP \>110 mmHg unresponsive to antihypertensive therapy). 13. Uncontrolled hypoglycemia/hyperglycemia (\<50 mg/dL \[2.8 mmol/L\] or \>400 mg/dL \[22.2 mmol/L\]). 14. Pregnancy or lactation. 15. A life expectancy of less than three months. 16. Participation in other clinical trials within 3 months or ongoing trial enrollment. 17. Inability to follow up (e.g., no fixed residence, overseas patients). 18. Patient deemed unsuitable for the trial by site investigator.