[Endoleaks - when is treatment necessary?].

Currently the majority of infrarenal abdominal aortic aneurysm repairs are endovascular procedures using a stent graft. This method continues to be questioned due to an up to 50 % incidence of endoleaks, i.e. the postinterventional persistence of blood flow outside the graft and within the aneurysm sac, potentially bearing the risk of a further increase of the aneurysm diameter and aneurysm rupture. Currently a total of five different endoleak types can be distinguished. Multiphase computed tomography (CT) is the standard imaging method for the detection and classification of endoleaks or alternatively contrast-enhanced ultrasound can be used. The different types of endoleak have very different therapeutic implications. In direct endoleaks (types I and III) the systemic blood pressure is directly transferred to the aneurysm wall which carries a high risk of rupture and in general an immediate intervention is indicated. Indirect endoleaks (types II, IV and V) take a more benign course and in the majority of cases treatment is only necessary when further aneurysm expansion occurs.