1. Evaluate the feasibility for the on-table evaluation of the renal perfusion by using Syngo Dyna Parenchymal Blood Volume(PBV) Body;
2. Explore the clinical benefits of this application during procedure to help the physician to determine the procedure endpoint.

Renal artery stenosis (RAS) is one of the potential manifestations of peripheral artery diseases and it is often observed in patients with evolving renal function impairment and concomitant coronary artery disease, or in those suffering from hypertension refractory to medical therapy.Percutaneous renal artery stenting is an effective therapeutic tool and represents the treatment of choice for RAS. Identification of parameters able to discriminate patients who benefit from RAS stenting, thus, has become of crucial importance if this technique has to survive.

Aortic dissection represents a common cardiovascular disease and it is responsible for the most commonly encountered pathologies in aortic emergency. Renal dysfunction is a common complication associated with aortic dissection, with resultant high mortality rate. The antegrade propagation of the dissection from the proximal aorta to the level of renal arteries and the intervention during surgery may both increase the risk of renal malperfusion; thus, it is important to assess renal function for pre- and post-operative evaluation and guidance for treatment. This can be achieved through perfusion imaging.

Presently, C-arm Cone Beam Computed Tomography (CBCT) perfusion is well established, in particular, in the diagnostic assessment of acute stroke and cerebral ischemia. The main novelty of our study lies in the fact that intra-procedural renal perfusion assessed for the first time semiquantitatively by Syngo Dyna Parenchymal Blood Volume(PBV) software, discriminate patients who will benefit from the intervention procedure.

In conclusion, our study suggests that a routine assessment of pre, and post-stenting renal perfusion could help to identify patients at higher risk of no improvement or even worsening of renal function after stenting and, perhaps, more aggressive medical therapy.

Inclusion Criteria:

• Renal artery stenosis ≥ 60% and < 100% by doppler ultrasonography, CT angiography or magnetic resonance angiography;
• Target kidney remains functional (GFR determined);
• The length of target kidney is >8cm;
• Resistance index tested by doppler ultrasonography <0.8;
• Comply with the protocol

Exclusion Criteria:

• Severe cardiopulmonary insufficiency, hepatic dysfunction, renal inadequacy and clotting mechanism abnormality;
• Pregnancy or lactation;
• History of renal artery surgery;
• Allergy of contrast agent;
• Other known reason nonischemic kidney disease

Consecutive patients who meet the inclusion criteria, are willing to comply with this protocol, and receive endovasculara therapy in the Department of Vascular Surgery, Zhongshan Hospital will be included.