Abstract: An apparatus for the fragmentation of a solid body surrounded by a fluid, in particular in a living being, by means of acoustic shock waves which are induced by the light of a laser. A reflector for acoustic waves focuses the shock waves onto the body. In the region of the reflector, an element is provided which consists of a material absorbing the laser light, and onto which the laser light is directed, so that the plasma state triggering the acoustic shock wave develops at the surface of the element. The apparatus thus has the advantage that even under unfavorable conditions acoustic shock waves can be generated with certainty at every laser pulse.

Abstract: A reordering system for reducing respiratory artifacts in magnetic resonance images. The respiration cycle of the patient is measured and divided into N exclusive intervals. A different encoding amplitude is assigned to each interval in a first look-up table (LUT). The encoding pulses are selected by the first LUT responsive to measured respitory intervals. After M encoding pulses have been selected, a new LUT is constructed from the unused encoding pulse amplitudes using a new number (N-M) intervals. The new LUT is then used for another given number of encoding pulses. Other new LUT's are constructed after given numbers of encoding pulses are used until all encoding pulses are used.

Abstract: A shock wave generator has a focusing stage wherein a number of different lenses having respectively different concentrating characteristics are accommodated, and which can be selectively introduced transversely into the path of the shock wave pulse, by linear displacement or by pivoting. The lenses can be alternatively introduced one at a time in one embodiment, or in a second embodiment more than one lens can be simultaneously introduced to achieve a concentrating characteristic resulting from a combination of lenses. For further adjustment and flexibility, the shock wave generator is provided with at least two capacitors for selectively varying the amount of discharge energy used to trigger the shock wave. The approach path between the membrane which generates the shock wave and the lens can also be varied.

Abstract: A method and apparatus for use with medical electrode systems that sense the integrity of lead connections and patient transthoracic impedance is provided. In an ECG electrode application, a carrier circuit (12) produces two carrier signals (S.sub.C1 and S.sub.C2) that are out of phase with each other. The S.sub.C1 signal is applied to an RA lead through a terminating impedance (Z1). The S.sub.C2 signal is applied to LA, LL and V leads through terminating impedances (Z2, Z3, and Z4). Each of the S.sub.C1 and S.sub.C2 carrier signals comprises a lead impedance frequency component (S.sub.LI) and an impedance respiration frequency component (S.sub.IR). First stage amplifiers (A1, A2, and A3) located in an ECG preamplifier (13) amplify the difference between a lead voltage on the RA lead (V.sub.RA) and lead voltages on the LA, LL, and V leads (V.sub.LA, V.sub.LL and V.sub.V). High pass filters (F1, F2 and F3) remove patient ECG signals from the outputs of A1, A2 and A3 to produce first stage output voltages (V.

Abstract: An ultrasound head of the type suitable for medical ultrasound therapy has a housing with an opening in which a resonator assembly is insertable. The resonator assembly is mounted in the opening of the housing so as to be removable. The assembly includes a carrier for a ceramic resonator disc, the carrier having an outwardly flanged edge which is received against an inside shoulder of the housing surrounding the opening, so that the carrier projects at least partially out of the opening. A pressing mechanism is provided for maintaining the assembly tight against the inside shoulder by applying pressure from the interior of the housing.

Abstract: A shock wave generator suitable for use in an extracorporeal lithotripsy device to disintegrate calculi in a life form in vivo has a flat coil connectable to a high voltage supply, a membrane assembly disposed opposite the coil and a housing, closed on one side by the membrane, filled with a shock wave transmissive fluid. The membrane assembly has a carrier plate of electrically insulating material, and an electrically conductive section applied at one side of the carrier. The membrane assembly is connected to the housing at its edge. The material of the carrier is insensitive to cavitation, and the carrier is elastically yielding at least in the region of its edge. The electrically conductive section is electrically insulated from the terminals of the coil, and the membrane assembly is attached to the housing so that the electrically conductive section faces the flat coil.

Abstract: A method for in vivo NMR imaging of the blood vessels and organs of a patient characterized by using a dark dye-like imaging substance consisting essentially of a stable, high-purity concentration of D.sub.2 O in a solution with water.

Abstract: The improved transvenous implantation method of the present invention involves entering a vein of a patient, translating through the vein to the patient's cardium atrium, anchoring onto the atrial lateral wall, puncturing the atrial lateral wall and forming a hole therein, exiting the atrium through the hole to the pericardial space and inserting the object into the pericardial space. The present invention also includes a method for the transvenous repair of a wound in the atrial lateral wall.

Abstract: A shock wave source has a coil carrier, a planar or concave coil, a membrane consisting of electrically conductive material and a foil consisting of electrically non-conductive material. The membrane is disposed between the coil and the foil so as to be held tightly therebetween but having a perimeter which is capable of substantially unrestrained movement. Upon the application of a high voltage pulse to the coil, the resulting field causes the membrane to be rapidly repelled, however, only the mechanical forces of the membrane act on the foil, with no electromagnetic forces generated by the coil acting on the foil. The resulting pressure pulse is intensified to form a shock wave pulse in a transmission medium adjacent to the foil.

Abstract: To provide for adjusted positioning of a pulse sensor (50) against the selected toe of a patient, while the patient is relaxed, and without applying substantial pressure of the sensor against the toe, a base plate is formed with a depression to receive the heel of the foot of the user, and a support element (20) is adjustably positioned on a pair of parallel vertically extending posts (17, 18), projecting from the base plate. The support element is a transverse structure, slidable on the posts, and having a shaft (30) to which a bail (42) is attached. The pulse sensor (50) is mounted on the horizontal portion (48) of the bail, and is slidable along and rotatable about the portion (48). In addition, the bail (42) is slidable sideways (B) with respect to the foot of the user, i.e. across the toes, movable back and forth with respect to the toe to be tested while the pulse sensor (50) is retained against the toe by a spring (34) biasing the shaft, and hence the bail, towards the toe.

Abstract: To permit loose and relaxed position of the hand of a patient over a vasometric apparatus, the apparatus is formed in the shape of a hollow domed housing within which a volume pulse sensor (30) is located, retained with resiliently adjustable bias force such that the sensing surface (33) of the volume pulse sensor extends just slightly above the outer surface of the domed housing. The spring force with which the sensor engages a finger (45) of the patient is adjustable by an externally adjustable disk or wheel (37).