Reference data relating to a portion of a patient anatomy during patient motion can be acquired from a magnetic resonance imaging system (MRI) to develop a patient motion library. During a time of interest, tracking data is acquired that can be related to the reference data. Partial volumetric data is acquired during the time of interest and at approximately the same time as the acquisition of the tracking data. A volumetric image of patient anatomy that represents a particular motion state can be constructed from the acquired partial volumetric data and acquired tracking data.

Described herein is a system and method of controlling real-time image-guided adaptive radiation treatment of at least a portion of a region of a patient. The computer-implemented method comprises obtaining a plurality of real-time image data corresponding to 2-dimensional (2D) magnetic resonance imaging (MRI) images including at least a portion of the region, performing 2D motion field estimation on the plurality of image data, approximating a 3-dimensional (3D) motion field estimation, including applying a conversion model to the 2D motion field estimation, determining at least one real-time change of at least a portion of the region based on the approximated 3D motion field estimation, and controlling the treatment of at least a portion of the region using the determined at least one change.

Apparatus and techniques are described herein for nuclear magnetic resonance (MR) projection imaging. Such projection imaging may be used to control radiation therapy delivery to a subject, such as including receiving reference imaging information, generating a two-dimensional (2D) projection image using imaging information obtained via nuclear magnetic resonance (MR) imaging, the 2D projection image corresponding to a specified projection direction, the specified projection direction including a path traversing at least a portion of an imaging subject, determining a change between the generated 2D projection image and the reference imaging information, and controlling delivery of the radiation therapy at least in part using the determined change between the obtained 2D projection image and the reference imaging information.

A method of controlling and processing data from a hybrid PET-MR imaging system includes acquiring a positron emission tomographic (PET) dataset over a time period, wherein the PET dataset is affected by a quasi-periodic motion of the patient, and acquiring magnetic resonance (MR) data during the time period such that the acquisition time of the MR data relative to the PET dataset is known. A characteristic of the patient motion is then determined based on the PET dataset and the MR data is processed based on the characteristic of patient motion.

The present invention relates to the locally resolved examination of objects by means of magnetic resonance (MR) and relates specifically to a less motion-artifact prone method for navigated multi-shot acquisition of diffusion-weighted image data using moment-nulled magnetic field gradients for diffusion encoding. The invention further relates to an apparatus for performing the method.

A magnetic resonance scanner (10) includes a main magnet (12), gradient coils (14) and a gradient coil controller (28), one or more RF coils (16,50), an RF transmitter (30), an RF receiver (34), and one or more processors (38). The main magnet (12) generates a B.sub.0 field. The gradient coils (14) and a gradient coil controller (28) generate gradients across the Bo field. The one or more RF coils (16,50) transmit B.sub.1 pulses and receive magnetic resonance signals. The RF transmitter (30) transmits B.sub.1 pulses to the RF coils to excite and manipulate resonance. The RF receiver (34) demodulates received resonance signals into data lines. The one or more processors (38) are connected to the gradient coil controller (28), the RF transmitter (30), and the RF receiver (34) and are programmed to control (70) the RF transmitter and the gradient coil controller to implement an interleaved multi-slice 2D imaging sequence which in each of a plurality of TRs generates a first and second navigation data lines and at least one image data line for each of a plurality of slices. The one or more processors are further programmed to reconstruct (74) the first navigation data lines from the plurality of slices into a first navigation projection image, reconstruct (74) the second navigation data lines from the plurality of slices into a second navigation image; and compare (76) successive navigation projection images to detect and adjust (78) for 3D motion.

A method detects phase-encoding ghosting in a MR image of an object to be imaged and mitigates the corresponding artifact in the MR image. The method includes acquiring MRI raw data of the object by a MRI apparatus. The MRI apparatus has multiple receiver channels for acquiring the MRI raw data. An artifact map of at least one part of the object to be imaged is calculated from the MRI raw data, the artifact map is configured for highlighting artifact appearing in the MR image. An outlier mask representing detected phase-encoding artifact is created in the artifact map. The phase-encode ghosting in the MR image is mitigated by using the previously obtained artifact map and the outlier mask for obtaining an improved MR image.

For imaging an object subject to a cyclic motion, two or more imaging repetitions are carried out. Each of the imaging repetitions includes a sequence of equally spaced imaging events, wherein each imaging event has an event number, which corresponds to a respective predefined imaging parameter. A cycle duration of the cyclic motion is determined, a number of events per cycle is determined based on the cycle duration and a shift number is determined at least in part randomly. For a first imaging repetition, a starting number is determined depending on the number of events per cycle and the shift number. The first imaging repetition is carried out, wherein the respective sequence is started with an imaging event, whose event number is given by the starting number.

During a focused-ultrasound or other non-invasive treatment procedure, the motion of the treatment target or other object(s) of interest can be tracked in real time based on (i) the comparison of treatment images against a reference library of images that have been acquired prior to treatment for the anticipated range of motion and have been processed to identify the location of the target or other object(s) therein and (ii) complementary information associated with the stage of the target motion during treatment.

Techniques for generating magnetic resonance (MR) images of a subject from MR data obtained by a magnetic resonance imaging (MRI) system, the techniques including: obtaining input MR data obtained by imaging the subject using the MRI system; generating a plurality of transformed input MR data instances by applying a respective first plurality of transformations to the input MR data; generating a plurality of MR images from the plurality of transformed input MR data instances and the input MR data using a non-linear MR image reconstruction technique; generating an ensembled MR image from the plurality of MR images at least in part by: applying a second plurality of transformations to the plurality of MR images to obtain a plurality of transformed MR images; and combining the plurality of transformed MR images to obtain the ensembled MR image; and outputting the ensembled MR image.