The apparatus for deployment of a therapeutic device such as a micro-coil detachably mounts the therapeutic device to a distal portion of a pusher member. In one embodiment, the therapeutic device is detachably mounted to the distal portion of the pusher member by a connector fiber for securing the therapeutic device to the pusher member. The connector fiber passes through a cutter member such as a cutting ring within the distal portion of the pusher member, for cutting the connector fiber to release the therapeutic device when a desired placement of the therapeutic device within the vasculature is achieved.