Methods and devices for treatment of a patient's cerebral aneurysm is described. The device includes a permeable shell having a radially constrained elongated state configured for delivery within a catheter lumen, an expanded state with a longitudinally shortened configuration relative to the radially constrained state, and a plurality of elongate filaments that are woven together to form a mesh. The proximal ends of each of the plurality of filaments are gathered by a proximal hub and the distal ends of each of the plurality of filaments are gathered by a distal hub. The proximal portion of the permeable shell includes a swellable polymer. The method includes advancing the implant in a microcatheter to a region of interest in the cerebral vasculature, deploying the implant within the cerebral aneurysm, and withdrawing the microcatheter from the region of interest after deploying the implant.