1. A method is provided for detection of the position and orientation of the tip of an elongated needle-like medical device inserted into a tissue of a patient using scanning apparatus, such method comprising: during an initial scan of the tissue with the apparatus, obtain several image slices through the tissue having therein the device, each one of the slices having a known orientation with respect to a reference co-ordinate system fixed with respect to the scanning apparatus; detecting the device in one of the slices obtained from the initial scan including determining the position and angular orientation of the device in such one of the slices; referencing the position and angular orientation of the device in such one of the slices with respect to the reference coordinate system of the scanning system to determine an appropriate imaging plane for a subsequent scan; repeating the process until a final slice is obtained having a predetermined degree of clarity of the entire needle-like device and with the longitudinal axis of the needle-like device disposed in a known orientation with respect to the reference co-ordinate system; and identifying the tip of the device in the final slice comprising obtaining data along lines transverse to the longitudinal axis of the device.