Effect of Endovascular Inferior Mesenteric Artery Embolization on Colonic Perfusion Prior to Rectal Surgery for Rectal Tumor or Sigmoid Colon Surgery

Inclusion Criteria: * The patient must have given their free and informed consent and signed the consent form * The patient must be a member or beneficiary of a health insurance plan * The patient is at least 18 years old and less than 80 years old * Patient has rectal cancer or sigmoid colon cancer requiring surgical treatment Exclusion Criteria: * The subject is participating in another study, or is in a period of exclusion determined by a previous study * The subject refuses to sign the consent * It is impossible to give the subject informed information * The patient is under safeguard of justice or state guardianship * Patient has a history of abdominal surgery * Patient suffers from a hemostasis disorder (hemophilia, von Willebrand disease, thrombocytopenia) and is on anticoagulant therapy. * Patient whose general condition appears too precarious or is taking corticosteroids or immunosuppressants leading to an unacceptable surgical risk. * Renal insufficiency with clearance \<45ml / min * Known allergy to contrast media * Patient who had treatment of the abdominal aorta or its branches Reported pregnancy (the existence of effective contraception will be verified for women of childbearing age). * Anatomical variant at risk or absence of marginal artery highlighted at the time of arteriography. * Abnormality of the superior mesenteric artery * Historic occlusion of the inferior mesenteric artery