摘要:
The invention provides for a medical instrument (200, 400, 500) comprising a magnetic resonance imaging system (202), a transducer (222) for mechanically vibrating at least a portion of the subject within the imaging zone. Instructions cause a processor (236) controlling the medical instrument to: control (100) the transducer to vibrate; control (102) the magnetic resonance imaging system to repeatedly acquire the magnetic resonance data (252) using a first spatially encoding pulse sequence (250); control (104) the magnetic resonance imaging system to acquire navigator data (256) using a second spatially encoding pulse sequence (254); construct (106) a set of navigator profiles (258, 804, 904, 1004, 1108, 1208, 1308) using the navigator data; determine (108) at least one parameter (260) descriptive of transducer vibrations using the set of navigator profiles; and reconstruct (110) at least one magnetic resonance rheology image (262) from the magnetic resonance data.
摘要:
An image dataset comprises multiple shots of imaging data acquired using a magnetic resonance imaging (MRI) scanner (10). The signal power of each shot of the image dataset is normalized (24) to a reference signal power to generate a power normalized shot representation having total signal power matching the reference signal power. A reconstructed image is generated (26) from the power normalized shot representations. Odd/even phase correction (22) may also be performed on the image dataset. The phase correction, normalizing, and generating operations are suitably performed by an electronic data processing device (20).
摘要:
A magnetic resonance imaging sequence is defined by an imaging protocol and parameter values for a set of parameters of the imaging protocol. A contrast signal score is computed for the magnetic resonance imaging sequence respective to a contrast type to be scored using a scoring equation. A contrast type is determined for the magnetic resonance imaging sequence based on the computed contrast signal score. In one approach, the computing is repeated for a plurality of different contrast types to be scored, and the determining is based on the computed contrast signal scores.
摘要:
A method of dynamic magnetic resonance imaging comprising acquiring undersampled magnetic resonance signels for successive temporal time slots. In a space spanned by geometrical space and temporal frequency and on the basic of a priori information the aliased difference magnetic resonance data which are gained by subtracting for respective k-space sampling positions data of a baseline magnetic resonance image from the undersampled magnetic resonance signals are decomposed into difference data which essentially pertain to individual spatial positions at individual time slots.
摘要:
A method for use in magnetic resonance imaging, or other imaging modality, wherein dynamic data is acquired in which the signal intensity of each pixel has a repetitive nature or in which (a subset of) the pixels have a common line shape. The common line shape of a data set comprising a plurality of signal intensity time curves is estimated by performing principal component analysis (PCA) in respect of the data set using a singular value decomposition (SVD) algorithm, wherein the first principal component is representative of the common line shape. Then, a time shift value is obtained using the common line shape and one or more of its derivatives and linear regression and applied to the respective signal intensity time curves to correct for random temporal shift in the repetitive elements.
摘要:
A system for manipulation of a body of fluid, in particular a fluid droplet comprises severalcontrol electrodes to which an adjustable voltage is applied to control displacement of the droplet on the basis of the electrowetting effect. There is a counter electrode having a fixed voltage between the body of fluid and one of the control electrodes. Further, as the counter electrode and the control electrodes are located at the same side of the fluid droplet, the fluid droplet is freely accessible at its side remote from the counter electrode and the control electrodes. Hence, the fluid droplet can be employed as an object carrier and a pay-load can be placed on the droplet from the freely accessible side.