Systems and methods for accelerated MR thermometry
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.
1. A method for accelerated magnetic resonance thermometry, comprising:
acquiring, by applying a magnetic; resonance imaging sequence generated by a magnetic resonance imaging device, undersampled k-space magnetic resonance data associated with an area of interest of a subject receiving focused ultrasound treatment, wherein the magnetic resonance imaging sequence comprises a three-dimensional interleaved stack-of-spirals spoiled gradient echo sequence; and
reconstructing images corresponding to the area of interest based on the acquired magnetic resonance data, wherein the reconstructing of the imams comprises:
reconstructing the images from the undersampled k-space data using Kalman filtering,
wherein the Kalman filtering comprises using a dynamic state-space model for the Kalman filtering,
wherein the center of k-space is fully sampled and provides low resolution images used for initial values and training data for noise covariance for the Kalman filtering, and
wherein the dynamic state-space model is according to:
x k =f ( x k-1 )+ w k
and
y k =U x Fx k +v k
wherein x k is target image at k th frame, y k is corresponding acquired data, f(x k-1 ) is state transition function, F is Fourier transform operator, U k is undersampling scheme at acquisition k, and w and v are system and measurement noise.
2. The method of claim 1 , further comprising:
measuring phase changes from proton-resonance frequency (PRF) shift associated with heating in the area of interest caused by the focused ultrasound treatment.
3. The method of claim 2 , further comprising:
based on at least one of the measured phase changes and images generated from the reconstruction, determining one or more characteristics associated with a physiological activity in the area of interest.
4. The method of claim 1 , wherein reconstructing the images includes reconstruction by 2D gridding.
5. A system for accelerated magnetic resonance thermometry, comprising,
a magnetic resonance imaging device configured to apply a magnetic resonance imaging sequence configured to acquire undersampled k-space magnetic resonance data associated with an area at interest of a subject receiving focused ultrasound treatment, wherein the magnetic resonance imaging sequence comprises a three-dimensional interleaved stack-of-spirals spoiled gradient echo sequence; and
an image reconstruction device configured to reconstruct images corresponding to the area at interest based on the acquired magnetic resonance data, wherein the reconstructing of the images comprises:
reconstructing the images from the undersampled k-space data using Kalman filtering,
wherein the Kalman filtering comprises using a dynamic state-space model for the Kalman filtering,
wherein the center of k-space is fully sampled and provides low resolution images used for initial values and training data for noise covariance for the Kalman filtering, and
wherein the dynamic; state-space model is according to:
x k f ( x k-1 )+ w k
and
y k =U x Fx k +v k
wherein x k is target image at k th frame, y k is corresponding acquired data, f(x k-1 ) is state transition function, F is Fourier transform operator, U k is undersampling scheme at acquisition k, and w and v are system and measurement noise.
6. The system of claim 5 , further comprising:
a phase change measurement device configured to measure phase changes from proton-resonance frequency (PRF) shift associated with heating in the area of interest caused at least in part by the focused ultrasound treatment.
7. The system of claim 6 , wherein the system further comprises:
one or more processors configured to execute instructions to cause the system to, based on at least one of the measured phase changes and the images generated from the reconstruction, determine one or more characteristics associated with a physiological activity in the area of interest.
8. The system of claim 5 , wherein reconstructing the images includes reconstruction by 2D gridding.
9. A non-transitory computer-readable medium storing instructions that, when executed by one or more processors, cause a computing device to perform a method for accelerated magnetic resonance thermometry that comprises:
causing a magnetic resonance imaging device to apply a magnetic resonance imaging sequence configured to acquire undersampled k-space magnetic resonance data associated with an area of interest of a subject receiving focused ultrasound treatment, wherein the magnetic resonance imaging sequence comprises a three-dimensional interleaved stack-of-spirals spoiled gradient echo sequence; and
reconstructing images corresponding to the area of interest based on the acquired magnetic resonance data, wherein the reconstructing of the images comprises:
reconstructing the images from the undersampled k-space data using Kalman filtering,
wherein the Kalman filtering comprises using a dynamic state-space model for the filtering,
wherein the center of k-space is fully sampled and provides low resolution images used for initial values and training data for noise covariance for the Kalman filtering, and
wherein the dynamic state-space model s according to:
x k =f ( x k-1 )+ w k
and
y k =U k Fx k +v k
wherein x k is target image at k th frame, y k is corresponding acquired data, f(x k-1 ) a state transition function, F a Fourier transform operator, U k is undersampling scheme at acquisition k and w and v are system and measurement noise.
10. The non-transitory computer-readable medium of claim 9 , wherein the method further comprises:
measuring phase changes from proton-resonance frequency (PRF) shift associated with heating in the area of interest caused by the focused ultrasound treatment.
11. The non-transitory computer-readable medium of claim 10 , wherein the method further comprises:
based on at least one of the measured phase changes and images generated from the reconstruction, determining one or more characteristics associated with a physiological activity in the area of interest.
12. The non-transitory computer-readable medium of claim 9 , wherein reconstructing the images includes reconstruction by 2D gridding.