30 results about "Mr contrast" patented technology

A system and method for using magnetic resonance imaging to increase the accuracy of electrophysiologic procedures is disclosed. The system in its preferred embodiment provides an invasive combined electrophysiology and imaging antenna catheter which includes an RF antenna for receiving magnetic resonance signals and diagnostic electrodes for receiving electrical potentials. The combined electrophysiology and imaging antenna catheter is used in combination with a magnetic resonance imaging scanner to guide and provide visualization during electrophysiologic diagnostic or therapeutic procedures. The invention is particularly applicable to catheter ablation, e.g., ablation of atrial fibrillation. In embodiments which are useful for catheter ablation, the combined electrophysiology and imaging antenna catheter may further include an ablation tip, and such embodiment may be used as an intracardiac device to both deliver energy to selected areas of tissue and visualize the resulting ablation lesions, thereby greatly simplifying production of continuous linear lesions. The invention further includes embodiments useful for guiding electrophysiologic diagnostic and therapeutic procedures other than ablation. Imaging of ablation lesions may be further enhanced by use of MR contrast agents. The antenna utilized in the combined electrophysiology and imaging catheter for receiving MR signals is preferably of the coaxial or “loopless” type. High-resolution images from the antenna may be combined with low-resolution images from surface coils of the MR scanner to produce a composite image. The invention further provides a system for eliminating the pickup of RF energy in which intracardiac wires are detuned by filtering so that they become very inefficient antennas. An RF filtering system is provided for suppressing the MR imaging signal while not attenuating the RF ablative current. Steering means may be provided for steering the invasive catheter under MR guidance. Other ablative methods can be used such as laser, ultrasound, and low temperatures.

Porphyrazines capable of localizing in a tumor of a mammal are disclosed. The porphyrazines are used in methods of imaging a tumor and in methods of treating tumors, either alone or in combination with a chemotherapeutic agent and / or radiation.

The present invention encompasses methods, apparatus, and computer based systems for identifying benign and malignant tumors in tissues such as soft tissues and particularly breast tissue using dynamic contrast-enhanced magnetic resonance imagining (DCE-MRI) and dynamic susceptibility contrast-enhanced magnetic resonance (DSC) imagining of the tumors. Some embodiments encompass the use of two dynamic MRI pulse sequences in intercalating mode during parenteral administration of an MR contrast substance, wherein one of said pulse sequences is optimized for spatial information and the other pulse sequence is adjusted for high temporal solution, the high-temporal dissolved sequence further comprising a double echo-collection sensitive towards both DCE and DSC for generating a number of different biomarker data such as pharmacokinetic biomarker data, descriptive DCE biomarkers and descriptive DSC biomarkers, and subsequently normalizing and comparing said data with corresponding data from corresponding benign and malign tumors, respectively.

Treatment of malignant tumors or other lesions by localized transfer of radio frequency electromagnetic energy into a portion of the body may be achieved by means of spatially localized magnetic resonance (MR). A magnetic field with appropriate spatial distribution and radio frequency tuned to the resonant frequency unique to the tumor treatment volume will cause selective therapeutic energy deposition or heating within the tumor (hyperthermia). The desired magnetic field distribution for the MR treatment volume may be achieved by means of a main static magnetic field with a superimposed magnetic field to define the treatment volume size and shape, positioned by a gradient magnetic field. Treatment may be enhanced by MR contrast agents (such as gadolinium) and pharmacologic agents. The therapy may be achieved by simultaneous resonance throughout an entire selected therapy volume, or successively point by point, or by superimposition of small volumes, including by successively excited points, lines or planes as practiced in prior art magnetic resonance imaging systems, facilitating simultaneous imaging and therapy. In a preferred embodiment, the invention is incorporated in a magnetic resonance imaging (MRI) scanner wherein the imager modified by the addition of a localizing magnet is used visually or by automated or semi-automated computer image processing to define and localize the treatment volume and the main magnetic field and positioning gradient fields are created by the same magnets used for imaging and the radio frequency apparatus used for Magnetic Resonance Therapy uses the same electronics and probe coil used for MRI.

Atherosclerosis is an inflammatory disease of the arterial walls and represents a significant health problem in developed nations. Described is a targeted Magnetic Resonance Imaging (MRI) contrast agent for in vivo imaging of early stage atherosclerosis. Early plaque development is characterized by the influx of macrophages, which express a class of surface receptors known collectively as the scavenger receptors (SR). The macrophage scavenger receptor class A (SRA) is highly expressed during early atherosclerosis. The macrophage SRA therefore presents itself as an ideal target for labeling of lesion formation. By coupling a known ligand for the scavenger receptor, dextran sulfate, to a MRI contrast agent, early plaque formation can be detected in vivo. Targeted MR contrast agents offer a unique opportunity to visualize early plaque development in vivo with high sensitivity and resolution, allowing or early diagnosis and treatment of atherosclerosis.

Treatment of malignant tumors or other lesions by localized transfer of radio frequency electromagnetic energy into a portion of the body may be achieved by means of spatially localized magnetic resonance (MR). A magnetic field with appropriate spatial distribution and radio frequency tuned to the resonant frequency unique to the tumor treatment volume will cause selective therapeutic energy deposition or heating within the tumor (hyperthermia). The desired magnetic field distribution for the MR treatment volume may be achieved by means of a main static magnetic field with a superimposed magnetic field to define the treatment volume size and shape, positioned by a gradient magnetic field. Treatment may be enhanced by MR contrast agents and pharmacologic agents. In a preferred embodiment, the invention is incorporated in a magnetic resonance imaging (MRI) scanner modified by the addition of a localizing magnet.

The present invention encompasses methods, apparatus, and computer based systems for identifying benign and malignant tumors in tissues such as soft tissues and particularly breast tissue using dynamic contrast-enhanced magnetic resonance imagining (DCE-MRI) and dynamic susceptibility contrast-enhanced magnetic resonance (DSC) imagining of the tumors. Some embodiments encompass the use of two dynamic MRI pulse sequences in intercalating mode during parenteral administration of an MR contrast substance, wherein one of said pulse sequences is optimized for spatial information and the other pulse sequence is adjusted for high temporal solution, the high-temporal dissolved sequence further comprising a double echo-collection sensitive towards both DCE and DSC for generating a number of different biomarker data such as pharmacokinetic biomarker data, descriptive DCE biomarkers and descriptive DSC biomarkers, and subsequently normalizing and comparing said data with corresponding data from corresponding benign and malign tumors, respectively.

In a method and apparatus for magnetic resonance (MR) imaging, a result image is provided based on multiple MR contrasts. The result image is indicative of a value of a magnetic parameter. MR data are acquired for the multiple contrasts at different time points, in each case following preparation of a magnetization. During the acquisition of the MR data, k-space is undersampled according to a respective undersampling scheme. The undersampling schemes of the different MR contrasts are different from one another.

Featured are a new class of reporter genes including reporter compositions as well as methods, MRI systems and MRI imaging kits related thereto. The genes according to the present invention provide MR contrast when the sample / subject is irradiated at a specific off-resonance radio-frequency (RF frequency), where the contrast mechanism utilizes chemical exchange saturation transfer (CEST) technique for imaging.

Off-resonance imaging uses two complementary contrast agents with the first agent (iron-oxide) particles transfected into cells which provide localized signals. The second agent is detected from a change in the off-resonance signal when present in the cells labeled by the first agent.

A compound comprising a chemical combination of a photodynamic tetra-pyrrolic compound with a plurality of radionuclide element atoms such that the compound may be used to enhance MR imaging and also be used as a photodynamic compound for use in photodynamic therapy to treat hyperproliferative tissue. The preferred compounds have the structural formula:where R1, R2, R2a R3, R3a R4, R5, R5a R6, R7, R7a, and R8 cumulatively contain at least two functional groups that will complex or combine with an MR imaging enhancing element or ion. The compound is intended to include such complexes and combinations and includes the use of such compounds for MR imaging and photodynamic therapy treatment of tumors and other hyperproliferative tissue.

The invention features a novel non-invasive approach for imaging, detecting and / or sensing metal ions with improved sensitivity and specificity in a biological sample or tissue. In certain embodiments, the invention provides a MR contrast-based approach for imaging, detecting and / or sensing metal ions in the biological sample / tissue containing various background ions by using 19F-based chemical exchange saturation transfer (CEST) technique.

The invention provides an ultra-small functional nanocluster. A nanoculster structure is formed by taking GSH as a template and chelating sulfydryl and carboxyl on the surface of GSH with Au atom andgadolinium Gd atom; two types of atoms are simultaneously coated in the nanoculster structure. The invention also provides an ultra-small functional nanoprobe with the surface modified by cNGR and a preparation method thereof. The ultra-small functional nanoprobe has the capability of specifically identifying tumor angiogenesis; the quantum confinement effect of the Au atom is used for generatingfluorescence and absorbing X-ray according to the adsorption coefficient, so that fluorescence imaging and CT imaging can be achieved; the Gd atom is used for shortening longitudinal relaxation time of free water protons and enhancing MR contrast ratio, so that the application of the ultra-small functional nanoprobe in the multimodal imaging of the tumor angiogenesis can be achieved. The preparednanoparticles are small in size being smaller than 10nm, high in biocompatibility and low in toxicity; through the application of modular assembly performance of the nano material, efficient synergy of multiple functions is achieved; the ultra-small functional nanoprobe is high in preparation yield and is suitable for large-batch production.

The invention relates to a magnetic resonance liver targeting contrast medium and a preparation method thereof, belonging to the technical field of medicine. The magnetic resonance liver targeting contrast medium is a superparamagnetism contrast medium which takes magnetic nanometer iron oxide granules as main components, the surface of a superparamagnetism iron oxide nanoparticle is modified by phospholipids or sugar anhydrides, wherein the phospholipids are taken as a nanometer reactor, the sugar anhydrides are taken as surface modifying materials, and the ratio of the magnetic nanometer iron oxides to the phospholipids is 1-40 to 1-50; besides, the magnetic resonance liver targeting contrast medium also comprises penetration regulators, such as the sugar anhydrides, a stabilizing agent, and the like, and a PH regulator and is prepared by a coprecipitation method under normal temperature and pressure. The invention takes biodegradable and metabolizable superparamagnetism metal oxides used inside bodies as the MR contrast medium, and the metabolizable superparamagnetism metal oxides exist in a dispersing medium which is physiologically accepted in a superparamagnetism granule dispersoid or a superparamagnetism fluid way and can be accumulated on a special targeting organ to be imaged.

Porphyrazines capable of localizing in a tumor of a mammal are disclosed. The porphyrazines are used in methods of imaging a tumor and in methods of treating tumors, either alone or in combination with a chemotherapeutic agent and / or radiation.

In a method and apparatus for magnetic resonance (MR) imaging, a result image is provided based on multiple MR contrasts. The result image is indicative of a value of a magnetic parameter. MR data are acquired for the multiple contrasts at different time points, in each case following preparation of a magnetization. During the acquisition of the MR data, k-space is undersampled according to a respective undersampling scheme. The undersampling schemes of the different MR contrasts are different from one another.

Porphyrazines capable of localizing in a tumor of a mammal are disclosed. The porphyrazines are used in methods of imaging a tumor and in methods of treating tumors, either alone or in combination with a chemotherapeutic agent and / or radiation.

What is described is a process for producing high-purity gadobutrol in a purity (according to HPLC) of more than 99.7 or 99.8 or 99.9% and the use for preparing a pharmaceutical formulation for parenteral administration. The process is carried out using specifically controlled crystallization conditions. The more recent developments in the field of the gadolinium-containing MR contrast agents (EP 0448191 B1, CA Patent 1341176, EP 0643705 B1, EP 0986548 B1, EP 0596586 B1) include the MRT contrast agent gadobutrol (Gadovist® 1.0) which has been approved for a relatively long time in Europe and more recently also in the USA under the name Gadavist®.

In a method, computer and magnetic resonance (MR) apparatus for normalizing MR contrast images of an examination object that has two chemically different substances (SW, SF), wherein the first substance produces a first image signal and the second substance produces a second image signal, a processor is provided with a complex-valued contrast having pixels with signal contributions from the first and second substances. A phase correction of this contrast image is performed by calculating a real-valued contrast from the amount of the image signals of each pixel of the complex-valued contrast image. A mathematically smooth correction map is determined based on a number of the pixels that have a defined real-valued contrast. The intensity of pixels of the complex-valued contrast image are homogenized with other scans based on the correction map.

Featured are a new class of reporter genes including reporter compositions as well as methods, MRI systems and MRI imaging kits related thereto. The genes according to the present invention provide MR contrast when the sample / subject is irradiated at a specific off-resonance radio-frequency (RF frequency), where the contrast mechanism utilizes chemical exchange saturation transfer (CEST) technique for imaging.

Disclosed is CT or MR contrast agent which comprises a base or carrier scaffold formed of a polyhydroxol compound having a linker to which a Gd-DOTA is covalently bonded. Also disclosed is a method of screening a patient for colon cancer using a CT or MR contrast, which method comprises administering to a patient undergoing screening a compound as above described.

Disclosed is CT or MR contrast agent which comprises a base or carrier scaffold formed of a polyhydroxol compound having a linker to which a Gd-DOTA is covalently bonded. Also disclosed is a method of screening a patient for colon cancer using a CT or MR contrast, which method comprises administering to a patient undergoing screening a compound as above described.

Multivalent CT or MR contrast agents and methods of making and using thereof are described herein. The agents contain a moiety, such as a polymer, that provides multivalent attachment of CT or MR contrast agents. Examples include, but are not limited to, multivalent linear polymers, branched polymers, or hyperbranched polymers, such as dendrimers, and combinations thereof. The dendrimer is functionalized with one or more high Z-elements, such as iodine. The high Z-elements can be covalently or non-covalently bound to the dendrimer. The dendrimers are confined in order to enhance CT contrast. In some embodiments, the moiety is confined by encapsulating the dendrimers in a material to form particles, such as nanoparticles. In other embodiments, the dendrimer is confined by conjugating the moiety to a material, such as a polymer, which forms a gel upon contact with bodily fluids.

The invention provides a novel trimodal prostate cancer targeting nano particle imaging agent and a preparation method thereof. Using endogenous and highly biologically compatible ultrafine organic melanin nanoparticles (UMNPs) as a carrier, a small molecular group with PSMA targeting function was coupled to the nanoparticles to obtain a prostate cancer-targeting Nanomolecular imaging probe PSMA‑PEG‑UMNPs, and direct labeling of nuclides with UMNPs surface active groups 89 Zr and T1-weighted magnetic resonance contrast agent Mn 2+ , to obtain a nanoprobe with PAI, MRI and PET three-modal imaging functions ( 89 Zr, Mn)-PSMA-PEG-UMNPs. The probe can specifically bind to the PSMA antigen on the surface of prostate cancer cells, and accurately locate the tissue with high expression of PSMA through optical, nuclear magnetic and nuclear medicine methods respectively, so as to realize the purpose of targeted multimodal molecular imaging diagnosis of tumors.

The invention features a novel non-invasive approach for imaging, detecting and / or sensing metal ions with improved sensitivity and specificity in a biological sample or tissue. In certain embodiments, the invention provides a MR contrast-based approach for imaging, detecting and / or sensing metal ions in the biological sample / tissue containing various background ions by using 19F-based chemical exchange saturation transfer (CEST) technique.

In a method, computer and magnetic resonance (MR) apparatus for normalizing MR contrast images of an examination object that has two chemically different substances (SW, SF), wherein the first substance produces a first image signal and the second substance produces a second image signal, a processor is provided with a complex-valued contrast having pixels with signal contributions from the first and second substances. A phase correction of this contrast image is performed by calculating a real-valued contrast from the amount of the image signals of each pixel of the complex-valued contrast image. A mathematically smooth correction map is determined based on a number of the pixels that have a defined real-valued contrast. The intensity of pixels of the complex-valued contrast image are homogenized with other scans based on the correction map.