A medical apparatus for placing an embolic coil at a preselected position within a vessel comprising a coil assembly having an embolic coil attached to a cylindrical headpiece having at least one bending point formed by a circumferential groove and a deployment catheter having a distal section for retaining the coil assembly such that, when the deployment catheter is pressurized with a fluid the distal section of the catheter expands radially to release the coil assembly at the preselected position.
