Patent classifications
G01R33/5635
METHOD AND APPARATUS FOR PROCESSING MAGNETIC RESONANCE DATA
A method of processing magnetic resonance (MR) data of a sample under investigation, includes the steps of providing the MR data being collected with an MRI scanner apparatus, and subjecting the MR data to a multi-parameter nonlinear regression procedure being based on a non-linear MR model and employing a set of input parameters, wherein the regression procedure results in creating a parameter map of model parameters of the sample, wherein the input parameters (initial values and possibly boundaries) of the regression procedure are estimated by a machine learning based estimation procedure applied to the MR data. The machine learning based estimation procedure preferably includes at least one of at least one neural network and a support vector machine. Furthermore, an MRI scanner apparatus is described.
Interleaved dual-contrast unenhanced magnetic resonance angiography
A method for dual-contrast unenhanced magnetic resonance angiography includes iteratively acquiring flow-dependent slices and flow-independent slices in a region. Each iteration of the acquisition process comprises identifying a flow-dependent slice location within the region and identifying a flow-independent slice location upstream from the flow-dependent slice location according to blood flow in the region. Each iteration further includes applying a first radio frequency (RF) saturation pulse to the region such that MR signals from veins in the region are substantially suppressed, and applying a second RF saturation pulse to the flow-dependent slice location such that MR signals from background muscle and arterial blood in the region are substantially suppressed. A flow independent slice is acquired at the flow-independent slice location after the second RF saturation pulse is applied and before unsaturated arterial blood has maximally flowed into the region. After acquiring the flow-independent slice, a flow-dependent slice is acquired.
COMBINED ARTERIAL SPIN LABELING AND MAGNETIC RESONANCE FINGERPRINTING
The invention provides for a method of operating a magnetic resonance imaging system for imaging a subject. The method comprises acquiring (700) tagged magnetic resonance data (642) and a first portion (644) of fingerprinting magnetic resonance data by controlling the magnetic resonance imaging system with tagging pulse sequence commands (100). The tagging pulse sequence commands comprise a tagging inversion pulse portion (102) for spin labeling a tagging location within the subject. The tagging pulse sequence commands comprise a background suppression portion (104). The background suppression portion comprises MRF pulse sequence commands for acquiring fingerprinting magnetic resonance data according to a magnetic resonance fingerprinting protocol. The tagging pulse sequence commands comprise an image acquisition portion (106). The method comprises acquiring (702) control magnetic resonance data (646) and a second portion (648) of the fingerprinting magnetic resonance data by controlling the magnetic resonance imaging system with control pulse sequence commands. The control pulse sequence commands comprise a control inversion pulse portion (202). The control pulse sequence commands comprise the background suppression portion (104). The control pulse sequence commands comprise the image acquisition portion (106). The method comprises reconstructing (704) tagged magnitude images (650) using the tagged magnetic resonance data. The method comprises reconstructing (706) a control magnitude images (652) using the control magnetic resonance data. The method comprises constructing (708) an ASL image by subtracting the control magnitude images and the tagged magnitude images from each other. The method comprises reconstructing (710) a series of magnetic resonance fingerprinting images (656) using the first portion of the fingerprinting magnetic resonance data and/or the second portion of the fingerprinting magnetic resonance data. The method comprises generating (712) at least one magnetic resonance parametric map (658) by comparing the series of magnetic resonance fingerprinting images with a magnetic resonance fingerprinting dictionary.
Blood Vessel Sizing Device
Medical devices and methods that provide for improved accuracy when positioning of a synthetic structure, such as a MEMS device or a stent, within a biological feature of a patient, such as a blood vessel, are disclosed. A blood vessel sizing device is configured for placement on the skin of a patient near a feature of interest (e.g. a blood vessel to be imaged). The device may include one or more radiopaque elements, including a target element, and one or more positioning markers having known sizes. A clinician may use the radiopaque elements to identify a portion of a blood vessel suitable for positioning of the synthetic structure.
Magnetic resonance imaging apparatus
An MRI apparatus includes a processing circuitry that executes a pulse sequence by which a data acquiring process is repeatedly performed multiple times where data is acquired every time each of waiting periods has elapsed since a tag pulse used for labeling a fluid flowing into an image taking region of a patient is applied, that acquires, at at least one time among the multiple times, data corresponding to one region by using a three-dimensional sequence, out of three-dimensional data acquired while being divided into regions, during each of the data acquiring processes corresponding to a first waiting period among the waiting periods, and that acquires data allocated to the one time by using a two-dimensional sequence, out of a slice of two-dimensional data corresponding to the entire three-dimensional data, during each of the data acquiring processes corresponding to a second waiting period different from the first waiting period.
Analog frequency-domain multiplexing for time-of-flight pet detector frontend electronics
A detector, includes a plurality of photomultiplier tubes each having an anode configured to generate an anode output signal and a frequency domain detector interface including a plurality of frequency domain coupling circuits. Each of the plurality of frequency domain coupling circuits is configured to receive the anode output signal from one of the plurality of photomultiplier tubes and pickoff one of a high-frequency component or a low-frequency component. Each of the plurality of frequency domain coupling circuits is further configured to generate a pass-through signal comprising a first of the high-frequency component or the low-frequency component.
SYSTEM AND METHOD FOR DYNAMIC MULTIPLE CONTRAST ENHANCED, MAGNETIC RESONANCE FINGERPRINTING (DMCE-MRF)
The present disclosure provides a method of DDCE-MRF. The method can include: a) introducing two or more contrast agents to a region of interest (ROI) of a subject, the two or more contrast agents having different relaxivities; b) measuring a T1 relaxation time and a T2 relaxation time for locations within the ROI using magnetic resonance fingerprinting (MRF); c) determining, using equations that relate the different relaxivities, the T1 relaxation time, the T2 relaxation time, and concentrations of the two or more contrast agents, the concentrations of the two or more contrast agents for each of the locations within the ROI; and d) producing an image depicting the ROI based, at least in part, on the concentrations of the two or more contrast agents.
Method and system for image processing to determine blood flow
Embodiments include a system for determining cardiovascular information for a patient. The system may include at least one computer system configured to receive patient-specific data regarding a geometry of the patient's heart, and create a three-dimensional model representing at least a portion of the patient's heart based on the patient-specific data. The at least one computer system may be further configured to create a physics-based model relating to a blood flow characteristic of the patient's heart and determine a fractional flow reserve within the patient's heart based on the three-dimensional model and the physics-based model.
Method for acquiring T2* and vascular images from magnetic resonance imaging system
According to the present invention, accurate T2* and vascular images are concurrently acquired by acquiring a T2* image without a flow compensation and a T2* image with a flow compensation and subtracting the two images to reconstitute an image showing the flow phenomenon. Furthermore, an accurate T2* image can be acquired by using the readout gradient without the flow compensation and also the accurate T2* and vascular images can be concurrently acquired. The clinical judgment for blood flow rate of the blood vessel and the clinical judgment for acute stroke can be concurrently made, and so the present invention can be widely utilized in clinical practice.
System and method for spiral volume imaging
A system and method for system for performing a magnetic resonance imaging (MRI) process using an MRI system is provided. A coil system includes a substrate configured to follow a contour of a portion of a subject to be imaged by the MRI system and at least one coil coupled to the substrate and forming a spiral pattern.