a method for fusion of live ultrasound imagery with computed tomography scan images or magnetic resonance images , the method comprising steps of acquiring a series of ct scan images or magnetic resonance images , acquiring a series of ultrasound images , applying a manual registration process on a computing device to register each of the ct scan images or magnetic resonance images with corresponding ultrasound images , and displaying on a display associated with the computing device the live ultrasound imagery and corresponding ct scan images or magnetic resonance images .