40 results about "Magnetic resonance thermometry" patented technology

Techniques for temperature measurement and correction in long-term MR thermometry utilize a known temperature distribution in an MR imaging area as a baseline for absolute temperature measurement. Phase shifts that arise from magnetic field drifts are detected in one or more portions of the MR imaging area, facilitating correction of temperature measurements in an area of interest.

During the thermal treatment of an anatomical zone of interest, tissue temperature within the zone may be determined with a computational model whose parameters are adjusted using spectroscopy-based temperature measurements at interfaces of fat and non-fat tissues.

Proton resonance frequency shift thermometry may be improved by combining multibaseline and referenceless thermometry.

The phase background of a proton resonance frequency shift treatment image may be estimated by fitting a combination of baseline images to the treatment image.

A method for photomagnetic imaging of tissue includes the steps of heating the tissue using light; measuring a change in temperature of the tissue with magnetic resonance thermometry; and creating an optical property map from the measured change in temperature. An apparatus for performing photomagnetic imaging of tissue which includes a light source to heat the tissue, a magnetic resonance imaging system to measure a change in temperature of the tissue, and a data processor to generate an optical property map from the measured change in temperature. An optical property map of tissue photomagnetic imaging of tissue produced by: heating the tissue using light; measuring a change in temperature of the tissue with magnetic resonance thermometry; and creating an optical property map from the measured change in temperature.

The invention relates to a method for monitoring temperatures of tissues around an active implantation object. The method is based on magnetic resonance temperature measurement technologies and adopts a magnetic resonance imaging system, wherein the magnetic resonance imaging system is used to generate at least one sequence 2 which is applied to clinical inspection or scientific researches or other purposes, as well as a sequence 3 applied to temperature distribution measurement. The method comprises the steps that (S11) the sequence 2 is used for scanning, and scanning of the temperature measurement sequence 3 is conducted alternately in the sequence 2; and (S12), safety evaluation is conducted according to a scanning result of the temperature measurement sequence 3. The method has the advantages that radio frequency temperature rise during MRI scanning of a patient carrying an implanted medical appliance can be monitored effectively; and hidden safety risks can be eliminated.

A method for reducing errors in the measurement of temperature by magnetic resonance, for use in magnetic resonance imaging-guided HIFU equipment, includes acquiring an MR phase image, as a reference image, before heating an area to be heated with the HIFU equipment; acquiring another MR phase image, as a heated image, during or after the heating by the HIFU equipment; and calculating the temperature change in the heated area according to said heated image and said reference image; and making compensation to said temperature change according to the change in the magnetic field caused by the position change of an ultrasonic transducer in said HIFU equipment. The method can reduce significantly the temperature errors resulting from the position changes of the ultrasonic transducer.

Disclosed is a method and system for steady state free precession based magnetic resonance thermometry that measures changes in temperature on a pixel by pixel basis. The method comprises generating an RF pulse sequence used to find the proton resonance frequency shift, which is proportional to temperature change, processing the resultant MRI data to measure the proton frequency shift, and converting the measured proton frequency shift into change in temperature data. Further disclosed is a method for identifying and compensating for temperature drifts due to core heating of the gradient magnet.

A medical apparatus (300, 400, 500, 600) comprising a magnetic resonance imaging system (302). The medical apparatus further comprises a memory (332) storing machine readable instructions (352, 354, 356, 358, 470, 472, 474) for execution by a processor (326). Execution of the instructions causes the processor to acquire (100, 202) spectroscopic magnetic resonance data (334). Execution of the instructions further cause the processor to calculate (102, 204) a calibration thermal map (336) using the spectroscopic magnetic resonance data. Execution of the instructions further causes the processor to acquire (104, 206) baseline magnetic resonance thermometry data (338). Execution of the instructions further causes the processor to repeatedly acquire (106, 212) magnetic resonance thermometry data (340). Execution of the instructions further cause the processor to calculate (108, 214) a temperature map (351) using the magnetic resonance thermometry data, the calibration thermal map, and the baseline magnetic resonance thermometry data.

Aspects of the present disclosure relate to magnetic resonance thermometry. In one embodiment, a method includes acquiring undersampled magnetic resonance data associated with an area of interest of a subject receiving focused ultrasound treatment, and reconstructing images corresponding to the area of interest based on the acquired magnetic resonance data, where the reconstructing uses Kalman filtering.

Systems and methods provide accelerated MR thermometry utilizing prior knowledge about the images to be reconstructed from incomplete k-space data, thereby facilitating accurate reconstruction. In various embodiments, missing data is computationally estimated using a machine learning algorithm such as a neural network, and an image is generated based on iteratively updated estimated missing information.

The invention discloses a one-stop vertebral tumor microwave ablation operation simulation method and device, and relates to the technical field of medical instruments and simulation, and the method comprises the following steps: obtaining a magnetic resonance image of a patient before an operation, carrying out the image segmentation of the magnetic resonance image, and building an individual model of the patient based on the segmented image; collecting magnetic resonance temperature measurement data when the phantom is heated, calculating distribution of heat source items according to the magnetic resonance temperature measurement data, and establishing a microwave probe model based on the distribution of the heat source items; conducting temperature simulation on different needle inserting positions, located in the individual model, of the microwave probe model, conducting thermal damage evaluation on temperature simulation results to determine the optimal needle inserting position and heating duration, and an operation simulation scheme of the to-be-ablated area is generated. The method can be used to assist doctors in quickly and accurately determining proper needle inserting positions and microwave heating parameters, and high dependence on experience of the doctors is effectively reduced.

In a method and magnetic resonance apparatus for determining at least one datum providing a measure for the effect of at least one medical device that is to be connected to, or is connected to, an examination subject in the scope of a magnetic resonance examination that is to be executed, or has been executed, on the image data that are to be obtained, or have been obtained, in the scope of a magnetic resonance examination that is to be executed, or has been executed, and/or on the examination subject that is to be examined, or has been examined, in the scope of the magnetic resonance examination that is to be executed, or has been executed, the at least one datum is determined by at least one magnetic resonance thermometric measurement.

Some aspects of the present disclosure relate to systems and methods for magnetic resonance thermometry. In one embodiment, a preliminary balanced steady state free precession (bSSFP) magnetic resonance imaging pulse sequence is applied to an area of interest of a subject. Based on bSSFP image phases, a relationship between frequency and image phase associated with the area of interest can be determined and a bSSFP magnetic resonance imaging pulse sequence applied for temperature change measurement during and/or after focused energy is applied to the subject. Based on image phase change associated with temperature change and using the determined relationship between frequency and image phase, a change in the resonance frequency associated with the target area due to the application of the focused energy can be determined, and the temperature change can be determined based on the determined change in the resonance frequency.