Annexin Imaging in Dissection of the Descending Aorta

Inclusion Criteria: * patient whose age is ≥ 18 years old * any patient seen more than 6 months and less than 5 years after a dissection involving the descending aorta at Bichat Hospital, whether it is a dissection of the descending aorta alone or a dissection of the ascending aorta extended to the descending aorta * dissection of the uncomplicated descending thoracic aorta: not requiring surgery or stent implantation within the first 6 months after acute dissection * effective contraception for women of childbearing age Exclusion Criteria: * scheduled procedure for dissection of the descending aorta * contraindication to aortic CT with injection of contrast media: renal failure with creatinine clearance \<30 ml/min or creatinine \>200 µmol/l; allergy to contrast media * history of surgery or stent implantation in the descending thoracic aorta * pregnant or breastfeeding women * patient under guardianship or trusteeship * non affiliation to social security or CMU (beneficiary or assignee) * patient refusal to participate in the study