Inclusion Criteria:  Patients above 18 years with proximal aortic dissection/aneurysm. Patients subjected to aortic surgery or intervention at Royal Brompton and Harefield Hospital. Patients agreeing to participate in this study and willing to give written consent.  Exclusion Criteria:  Patients not suitable for surgery or intervention. Patients with pre-existing cancer condition or cancer predisposition. Patients who are pregnant. Patient with critical renal function who cannot tolerate to standard amount contrast agent. Patients who cannot give written informed consent.