A clot removal device has an expandable treatment member, a proximal section, and a transition section having a distal end connected to the proximal end of the expandable treatment member, and a proximal end connected to the distal end of the proximal section. A delivery wire has a distal end coupled to the proximal section. The diameter of the proximal section is smaller than the diameter of the expandable treatment member, and the transition section has a diameter that varies from its proximal end to its distal end.