This study is multi-center, prospective, randomized (1:1) controlled trial designed to assess and compare the feasibility, safety and success of Transradial access (TRA) versus Transfemoral access (TFA) for diagnostic cerebral angiography.

TFA is traditional approach for diagnostic cerebral angiography, which has several limitations and complications including pain and discomfort, retroperitoneal hemorrhage, pulmonary embolism and increased admissions. Transradial coronary angiography has demonstrated preponderance to circumvent this limitations and complications. However, this has not been studied in cerebral angiography. So, the purpose of this study is to assess and compare the feasibility, safety and success of TRA versus TFA for diagnostic cerebral angiography.

Inclusion Criteria:

1. Age between 18 and 80 years old;
2. Scheduled to undergo diagnostic cerebral angiography;
3. Suitable for cerebral angiography via TRA and TFA access, with a radial artery diameter ≥2mm confirmed by ultrasonography;
4. Modified Rankin Scale (mRS) score ≤2;
5. Provided written informed consent.

Exclusion Criteria:

1. Severe stenosis of the radial, brachial, subclavian, brachiocephalic, iliac or common femoral arteries, or any significant vascular disease (such as aortic aneurysm, etc.) that may obstruct guidewire passage;
2. Arteriovenous fistula for hemodialysis present in the right upper limb;
3. Planned interventional surgery within 24 hours of the initial study angiography;
4. Requirement for cerebral angiography in an emergency department;
5. Use of general anesthesia;
6. Any contraindication to cerebral angiography, such as allergy or intolerance to the contrast media, uncorrected severe coagulation disorders, arterial dissection in the target vessel, puncture site infection, or renal insufficiency (Creatinine [Gr] > 3 times of the upper limit of normal [ULN]), etc.;
7. Women who are pregnant or planning to become pregnant within 1 year;
8. Participation in another clinical trial;
9. Any other condition deemed unsuitable for participation by the investigator.