6130results about "Measurements using NMR imaging systems" patented technology

A method and system for physiological gating is disclosed. A method and system for detecting and predictably estimating regular cycles of physiological activity or movements is disclosed. Another disclosed aspect of the invention is directed to predictive actuation of gating system components. Yet another disclosed aspect of the invention is directed to physiological gating of radiation treatment based upon the phase of the physiological activity. Gating can be performed, either prospectively or retrospectively, to any type of procedure, including radiation therapy or imaging, or other types of medical devices and procedures such as PET, MRI, SPECT, and CT scans.

A method and apparatus is provided for magnetic source magnetic resonance imaging. The method includes collecting energy signals from an object, providing additional information of characteristics of the object, and generating the image of the object from the energy signals and from the additional information such that the image includes a representation of a quantitative estimation of the characteristics, e.g a quantitative estimation of magnetic susceptibility. The additional information may comprise predetermined characteristics of the object, a magnitude image generated from the object, or magnetic signals collected from different relative orientations between the object and the imaging system. The image is generated by an inversion operation based on the collected signals and the additional information. The inversion operation minimizes a cost function obtained by combining the data extracted from the collected signals and the additional information of the object. Additionally, the image is used to detect a number of diagnostic features including microbleeds, contract agents and the like.

Methods are disclosed for assessing the condition of a cartilage in a joint and assessing cartilage loss, particularly in a human knee. The methods include converting an image such as an MRI to a three dimensional map of the cartilage. The cartilage map can be correlated to a movement pattern of the joint to assess the affect of movement on cartilage wear. Changes in the thickness of cartilage over time can be determined so that therapies can be provided. The amount of cartilage tissue that has been lost, for example as a result of arthritis, can be estimated.

A method for stimulating a particular area of a brain using a stimulation device includes detecting a spatial structure of a head and determining electrical and / or magnetic properties of at least one part of anatomical structures of the head. An energy amount to be provided by the stimulation device for stimulating the particular area of the brain is calculated automatically based on the spatial structure of the head and the determined electrical and / or magnetic properties of at least one part of the anatomical structures of the head.

An apparatus and method for performing treatment on an internal target region while compensating for breathing and other motion of the patient is provided in which the apparatus comprises a first imaging device for periodically generating positional data about the internal target region and a second imaging device for continuously generating positional data about one or more external markers attached to the patient's body or any external sensor such as a device for measuring air flow. The apparatus further comprises a processor that receives the positional data about the internal target region and the external markers in order to generate a correspondence between the position of the internal target region and the external markers and a treatment device that directs the treatment towards the position of the target region of the patient based on the positional data of the external markers.

In accordance with the present invention there is provided methods for generating an isotropic or near-isotropic three-dimensional images from two-dimensional images. In accordance with the present invention the method includes, obtaining a first image of a body part in a first plane, wherein the first image generates a first image data volume; obtaining a second image of the body part in a second plane, wherein the second image generates a second image data volume; and combining the first and second image data volumes to form a resultant image data volume, wherein the resultant image data volume is isotropic or near-isotropic.

A magnetic resonance (MR) imaging apparatus and technique exploits spatial information inherent in a surface coil array to increase MR image acquisition speed, resolution and / or field of view. Magnetic resonance response signals are acquired simultaneously in the component coils of the array and, using an autocalibration procedure, are formed into two or more signals to fill a corresponding number of lines in the signal measurement data matrix. In a Fourier embodiment, lines of the k-space matrix required for image production are formed using a set of separate, preferably linear combinations of the component coil signals to substitute for spatial modulations normally produced by phase encoding gradients. One or a few additional gradients are applied to acquire autocalibration (ACS) signals extending elsewhere in the data space, and the measured signals are fitted to the ACS signals to develop weights or coefficients for filling additional lines of the matrix from each measurement set. The ACS lines may be taken offset from or in a different orientation than the measured signals, for example, between or across the measured lines. Furthermore, they may be acquired at different positions in k-space, may be performed at times before, during or after the principal imaging sequence, and may be selectively acquired to optimized the fitting for a particular tissue region or feature size. The in vivo fitting procedure is readily automated or implemented in hardware, and produces an enhancement of image speed and / or quality even in highly heterogeneous tissue. A dedicated coil assembly automatically performs the calibration procedure and applies it to measured lines to produce multiple correctly spaced output signals. One application of the internal calibration technique to a subencoding imaging process applies the ACS in the central region of a sparse set of measured signals to quickly form a full FOV low resolution image. The full FOV image is then used to determine coil sensitivity related information and dealias folded images produced from the sparse set.

A method of slice selective multiple quantum magnetic resonance imaging of an object is disclosed. The method is effected by implementing the steps of (a) applying a radiofrequency pulse sequence selected so as to select a coherence of an order n to the object, wherein n is zero, a positive or a negative integer other than ±1; (b) applying magnetic gradient pulses, so as to select a slice of the object to be imaged arid to create an image; and (c) acquiring a radiofrequency signal resulting from the object, so as to generate a magnetic resonance slice image of the object. The method provides slice selective multiple quantum magnetic resonance images of yet unprecedented quality in terms of contrast. The method is particularly useful for imaging connective tissues.

An electromagnetic shield has a first patterned or apertured layer having non-conductive materials and conductive material and a second patterned or apertured layer having non-conductive materials and conductive material. The conductive material may be a metal, a carbon composite, or a polymer composite. The non-conductive materials in the first patterned or apertured layer may be randomly located or located in a predetermined segmented pattern such that the non-conductive materials in the first patterned or apertured layer are located in a predetermined segmented pattern with respect to locations of the non-conductive materials in the second patterned or apertured layer.

Systems and methods using magnetic resonance imaging for monitoring the temperature of a tissue mass being heated by energy converging in a focal zone that is generally elongate and symmetrical about a focal axis. A first plurality of images of the tissue mass are acquired in a first image plane aligned substantially perpendicular to the focal axis. A cross-section of the focal zone in the first image plane is then defined from the first plurality of images. A second plurality of images are acquired of the tissue mass in a second image plane aligned substantially parallel to the focal axis, the second image plane bisecting the first image plane at approximately a midpoint of the defined focal zone cross-section.

To produce a black body angiographic image representation of a subject (42), an imaging scanner (10) acquires imaging data that includes black blood vascular contrast. A reconstruction processor (38) reconstructs a gray scale image representation (100) from the imaging data. A post-acquisition processor (46) transforms (130) the image representation (100) into a pre-processed image representation (132). The processor (46) assigns (134) each image element into one of a plurality of classes including a black class corresponding to imaged vascular structures, bone, and air, and a gray class corresponding to other non-vascular tissues. The processor (46) averages (320) intensities of the image elements of the gray class to obtain a mean gray intensity value (322), and replaces (328) the values of image elements comprising non-vascular structures of the black class with the mean gray intensity value.

A phased-array knee coil is provided and includes a transmit coil array and a receive coil array having a plurality of coils configured to provide a first imaging mode and a second imaging mode.

In a method and apparatus for magnetic resonance imaging of an interconnected region of a human body on the basis of a partially parallel acquisition (PPA) by excitation of nuclear spins and measurement of the radio-frequency signals produced by the excited nuclear spins, a number of spin excitations and measurements of an RF response signal are implemented simultaneously in every component coil of a number of RF reception coils. As a result a number of response signals are acquired that form a reduced dataset of received RF signals for each component coil. Additional calibration data points are acquired for each reduced dataset. A complete image dataset is formed for each component coil on the basis of the reduced dataset for that component coil and at least one further, reduced dataset of a different component coil. A spatial transformation of the image dataset of each component coil is implemented in order to form a complete image of each component coil.

Methods for generating a three-dimensional visualization image of an object, such as an internal organ, using volume visualization techniques are provided. The techniques include a multi-scan imaging method; a multi-resolution imaging method; and a method for generating a skeleton of a complex three dimension object. The applications include virtual cystoscopy, virtual laryngoscopy, virtual angiography, among others.

This invention relates generally to NMR systems for in vivo detection of analytes. More particularly, in certain embodiments, the invention relates to systems in which superparamagnetic nanoparticles are exposed to a magnetic field and radio frequency (RF) excitation at or near the Larmor frequency, such that the aggregation and / or disaggregation of the nanoparticles caused by the presence and / or concentration of a given analyte in a biological fluid is detected in vivo from a monitored RF echo response.

Methods of predicting fracture risk of a patient include: obtaining an image of a bone of the patient; determining one or more bone structure parameters; predicting a fracture line with the bone structure parameter; predicting a fracture load at which a fracture will happen; estimating body habitus of the patient; calculating a peak impact force on the bone when the patient falls; and predicting a fracture risk by calculating the ratio between the peak impact force and the fracture load. Inventive methods also includes determining the effect of a candidate agent on any subject's risk of fracture.

The present invention relates to methods, software and systems for monitoring fluctuations in magnetic resonance signals. These methods may be used for measurements of the human brain and nervous system, and may be used for measuring electric currents and electromagnetic fields internal to an object. This method may include the use of a reference signal to accomplish differential recording of electromagnetic fields from two or more spatial locations.

A method and apparatus for classifying possibly malignant lesions from sets of DCE-MRI images includes receiving a set of MRI slice images obtained at respectively different times, where each slice image includes voxels representative of at least one region of interest (ROI). The images are processed to determine the boundaries of the ROIs and the voxels within the identified boundaries in corresponding regions of the images from each time period are processed to extract kinetic texture features. The kinetic texture features are then used in a classification process which classifies the ROIs as malignant or benign. The malignant lesions are further classified to separate TN lesions from non-TN lesions.

A method and system for physiological gating is disclosed. A method and system for detecting and predictably estimating regular cycles of physiological activity or movements is disclosed. Another disclosed aspect of the invention is directed to predictive actuation of gating system components. Yet another disclosed aspect of the invention is directed to physiological gating of radiation treatment based upon the phase of the physiological activity. Gating can be performed, either prospectively or retrospectively, to any type of procedure, including radiation therapy or imaging, or other types of medical devices and procedures such as PET, MRI, SPECT, and CT scans.

Brain Magnetic Resonance Imaging (MRI), Computerized Tomotography (CT), or other diagnostic modalities may employ a three-step procedure during initial (“scout”) cranial pre-scans that corrects for patient positioning (i.e., roll, yaw and pitch) to reduce inter- and intra-patient variation, thereby enhancing the diagnostic and comparative value of subsequent detail scans even across different diagnostic platforms. In MRI, for instance, locating the saggital sinus (SS) and optimizing a line to bisect the brain through this SS may be automated to correct for roll and yaw. By then identifying the contour of the corpus callosum in a lateral saggital scout scan, the Talairach anterior commissure (AC)—posterior commissure (PC) reference line may be found for correcting pitch. Prescription of detailed scans are improved, especially when the three-step correction is repeated periodically identifying the need to repeat a detailed scan or to adjust the coordinates of a subsequent scan.

Data collected by a transcranial brain function measuring / stimulating method is accurately projected and displayed onto a brain surface. If there is no three-dimensional head image, data is projected and displayed onto the brain surface of a standard brain. The head surface coordinates are transformed to the brain surface coordinates of the brain surface underlying the head surface by, e.g., a minimum distance search method. The coordinates of a projected point on the brain surface of the head surface and the probability distribution are determined for a standard brain normalized with data on subjects.

A computer assisted method is provided for diagnosing the in condition of a subject associated with particular activation in one or more regions of interest, the method comprising: having the subject perform a behavior or have a perception adapted to selectively activate one or more regions of interest associated with the condition; measuring activity of the one or more regions of interest as the behavior is performed or the subject has the perception; diagnosing the condition associated with the one or more regions of interest based on the activity in response to the behavior or perception; performing an intervention; and repeating this process one or more times including repeating said behavior, said measuring of activity and said diagnosis at a later time; and observing changes between measurements that are associated with said intervention.

Methods for generating a three-dimensional visualization image of an object, such as an internal organ, using volume visualization techniques are provided. The techniques include a multi-scan imaging method; a multi-resolution imaging method; and a method for generating a skeleton of a complex three dimension object. The applications include virtual cystoscopy, virtual laryngoscopy, virtual angiography, among others.