Procedure and principles in ultrasonically guided puncture.

It is the aim in ultrasonically guided puncture to place the tip of an appropriate needle safely and accurately in the suspect lesion or organ, vessel or duct. Thereby representative specimens of fluid or solid tissue are obtained, various agents, e.g. X-ray contrast media may be injected or catheters left for drainage. Simultaneous visualization of the target, the surrounding tissues, part of the needle and its tract has become possible with dynamic scanners of different types. The adjunct of needle steering devices significantly reduces the number of puncture attempts and in most cases the puncture route can be pre-determined precisely, so that readjustment of the puncture direction is unnecessary, unless puncture of different sites in the target is directly intended. The practical performances of such punctures are described together with the necessary equipment and remedies.