Abstract: In a method of contrast MR imaging, using parenterally administered contrast agents, the improvement comprising using as the contrast agent, e.g. to achieve a negative contrast effect, composite particles comprising a biotolerable, carbohydrate or carbohydrate derivative, preferably polymeric, matrix material containing magnetically responsive particles, eg. of magnetite.

Abstract: The properties of a tissue extracellular space, particularly the microvascular component of that space can be characterized by the use of x-ray diagnostic modalities in conjunction with particulate contrast agents. The present invention provides a method for characterizing a property of a tissue extravascular space utilizing radiopaque particulate contrast. Moreover, the present invention provides a novel class of particulate agents suitable for use in conjunction with the methods provided herein.

Abstract: Microballoons having a mean size in the range of 0.5 to 1000 microns bounded by a 50 to 500 nm thick biodegradable, interfacially deposited, synthetic polymer membrane which is both deformable and resilsient. These microballoons are used for ultrasonic echographic imaging of body organs.

Abstract: Microparticles are provided comprising a shell of an outer layer of a biologically compatible material and an inner layer of biodegradable polymer. The core of the microparticles contain a gas, liquid or solid for use in drug delivery or as a contrast agent for ultrasonic contrast imaging. The microparticles are capable of passing through the capillary systems of a subject.

Abstract: Microparticles useful for enhancing the ultrasound image of a tissue or organ consist of liquid and/or gas core material which is encapsulated by a biocompatible, tanned protein shell. These stabilized microparticles are useful as ultrasonic imaging agents, and are additionally useful in the further production of functionalized microparticles for in vivo imaging. In particular, targeting molecules such as antibodies or other ligands can be attached to the strengthened exterior surface of the stabilized microparticles to impart target-specificity to the microparticles. The targeting molecules may also provide hydrophilicity to the exterior surface, thus increasing the recirculation time of the microparticles. The targeting molecules may be attached directly to the exterior surface of the microparticles, or they may be attached via a bifunctional spacer arm, which may itself be hydrophilic.

Abstract: Cascade polymers, containing complex-forming ligands, optionally at least five ions of an element of atomic numbers 21-29, 39, 42, 44 or 57-83, as well as, if desired, cations of inorganic and/or organic bases, amino acids or amino acid amides, are valuable complexing compounds and complexes for diagnostics and therapy.

Abstract: Chelates of the compounds of formula I in which R is a hydrophilic group containing 3 or 4 successive phenyl rings and m is 1 or 2, with metal ions, for use in diagnostic imaging.

Abstract: Disclosed are injectable suspensions of gas filled microbubbles in an aqueous carrier liquid usable as contrast agents in ultrasonic echography. The suspensions comprise amphipathic compounds of which at least one may be a laminarized phospholipid as a stabilizer of the microbubbles against collapse with time and pressure. The concentration of phospholipids in the carrier liquid is below 0.01% wt but is at least equal to or above that at which phospholipid molecules are present solely at the gas microbubble-liquid interface. Also disclosed is a method of preparation of the stable suspensions of air or gas filled microbubbles.

Abstract: Cascade polymers, containing complex-forming ligands, optionally at least five ions of an element of atomic numbers 21-29, 39, 42, 44 or 57-83, as well as, if desired, cations of inorganic and/or organic bases, amino acids or amino acid amides, are valuable complexing compounds and complexes for diagnostics and therapy.

Abstract: The invention relates to injectable media for ultrasonic echography in the form of microbubbles or microballoons comprising at least two biocompatible substances A and B (gaseous at the body temperature) forming a mixture which when in suspension with usual surfactants, additives and stabilisers provides useful ultrasound contrast agents. At least one of the components (B) in the mixture is a gas whose molecular weight is greater than 80 daltons and whose solubility in water is below 0.0283 ml per ml of water at standard conditions. The presence of the first component (B) in the contrast medium may vary between 0.5 and 41 volume percent. The other component (A) of the ultrasound contrast media is a gas or a mixture of gases whose molecular weight is below 80 daltons. The second component is present in a proportion of between 59-99.5% by vol., and is preferably chosen from oxygen, air, nitrogen, carbon dioxide or mixtures thereof.

Abstract: The invention relates to ultrasonic contrast agents comprising microparticles which comprise synthetic biodegradable polymers and a gas and/or a fluid with a boiling point below 60° C., processes for the preparation thereof and their use as diagnostic and therapeutic agents.

Abstract: A contrast agent for use in diagnostic studies, particularly ultrasound imaging, comprising a dispersion in an injectable aqueous medium of a biocompatible azeotropic mixture which is in gaseous form at 37° C., at least one component of said mixture being a halocarbon having a molecular weight of at least 100.

Abstract: The invention provides a marker whose position in a cavity inside of a living organism can be determined, in particular for detecting local passage speeds of the marker through the gastro-intestinal tract, preferably in the small intestinal tract. The object of the invention is to provide a marker whose magnetization can be reversed with relatively low field intensities. To that end, the marker consists of a first substantially spherical part which contains a magnetizable material and is surrounded on all sides by a second part which is provided with a substantially spherical receptacle adapted to the surface shape of the first part, the receptacle being filled with a low-viscosity fluid.

Abstract: A method and apparatus for the detection of nuclear magnetic resonance (NMR) signals and production of magnetic resonance imaging (MRI) from samples combines the use of hyperpolarized inert gases to enhance the NMR signals from target nuclei in a sample and a high critical temperature (Tc) superconducting quantum interference device (SQUID) to detect the NMR signals. The system operates in static magnetic fields of 3 mT or less (down to 0.1 mT), and at temperatures from liquid nitrogen (77K) to room temperature. Sample size is limited only by the size of the magnetic field coils and not by the detector. The detector is a high Tc SQUID magnetometer designed so that the SQUID detector can be very close to the sample, which can be at room temperature.

Abstract: Disclosed herein are agents for enhancing the contrast in an ultrasound image. These agents are extremely small bubbles, or "microbubbles," comprised of specially selected gases. The microbubbles described herein exhibit long life spans in solution and may be produced at a size small enough to traverse the lungs, thus enabling improved ultrasound imaging of the cardiovascular system and other vital organs. Also disclosed herein is a method for selecting gases from which contrast agents may be produced. The method is based on calculations using inherent physical properties of gases and describes a means to associate the properties of a gas with the time for dissolution of microbubbles comprised of the gas.

Abstract: The present invention provides a method of contrast enhanced ultrasonic diagnostic imaging comprising administering to a subject a contrast enhancing amount of spheres or particles comprising a matrix enclosing a contrast agent which reflects sound waves, and generating an ultrasonic image of said subject wherein the matrix comprises a polymer held together by chemical bonds and wherein the polymer is selected from the group consisting of acrylates, polystyrene and derivatives thereof.

Abstract: A compound of formula (I): ##STR1## wherein, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are selected independently from hydrogen, alkyl, and alkyl substituted with one or more --O-- atoms, or where R.sup.1, R.sup.2 and R.sup.3, R.sup.4 are ring residues. The compound is capable of functioning as a ligand and complexing with paramagnetic Fe(III) ion for use as a second-sphere contrast enhancing agent for magnetic resonance imaging of tissue, and a method of administering the second sphere contrast agent.

Abstract: A method for imaging mammalian tissue utilizing a non-ionic complex of a paramagnetic ion of lanthanide element and a macrocyclic chelating agent.

Abstract: Methods of making Ultrasonic contrast agents useful for echographic imaging body organs comprising a suspension of gas or air filled microballoons having a mean size in the range of 0.5 to 1000 microns bounded by a 50 to 500 nm thick biodegradable, interfacially deposited, synthetic polymer membrane which is both deformable and resilient are as described.

Abstract: Gas or air filled microbubble suspensions in aqueous phases usable as imaging contrast agents in ultrasonic echography. They contain laminarized surfactants and, optionally, hydrophilic stabilizers. The laminarized surfactants can be in the form of liposomes. The suspensions are obtained by exposing the laminarized surfactants to air or a gas before or after admixing with an aqueous phase.