Type II endoleak: a problem to be solved.

Type II endoleak is a common phenomenon after endovascular aortic aneurysm repair (EVAR). The majority of type II endoleaks are considered benign, since approximately one third of them resolve spontaneously and they have no influence on mortality and rupture rate after EVAR. Thus, type II endoleak without sac expansion is recommended to be observed conservatively. Treatment for type II endoleak with sac expansion is still controversial. It has been reported that a certain type II endoleak causes sac expansion and late aneurysm rupture. Type II endoleak is often treated with solid agents as coils and vascular plugs or with liquid agents as different glues and thrombin. Onyx™ is a relatively new liquid embolic agents and it seems promising due to its capability to be injected in controlled manner with good visualization. Perisac embolization is another novel technique and it deals with all patent arterial branches, yet it requires further long-term studies. There are several access routes in treatment for type II endoleak. Translumbar approach seems more successful and safe than transarterial approach, and transcaval approach reduces the risk for infection compared to translumbar embolization. However, success rate of intervention for type II endoleak is unsatisfactory and recurrence rate is high. Endovascular treatment for type II endoleak is dependent on its nature and sometimes it can be challenging. Therefore, treatment for type II endoleak, including preventive embolization should be considered carefully and development of embolization methods is essential.