A hand-held actuator device for releasing into the body from a delivery system a medical prosthesis, like a stent, comprising a frame (10) that acts as a housing, a reel (30) for receiving a wire (8), a manually operable slider (34) mounted to the frame and a one-way connection between the slider and the reel. Actuating the slider causes the reel to wind up the wire and release the medical prosthesis.
