Treatment of aneurysms can be improved by use of a treatment system including a conduit have a distal portion, a coupler slidably coupled to the distal portion, an occlusive member coupled to the coupler, and a securing member coupled to the conduit proximal to the coupler. The securing member can include a distal end portion that is removably coupled to the coupler. In some embodiments, the securing member can have a shape and/or be treated such that the securing member self-expands to decouple itself from the coupler during deployment of the occlusive member. In some embodiments, movement of the conduit relative to the coupler causes the securing member to decouple from the coupler.