Systems and methods for determining scanning parameter in imaging

1. A method for determining at least one scanning parameter for a scanning by an imaging device, implemented on a machine having at least one processor and a storage device, the method comprising:

obtaining a scout image of at least one portion of a subject;

determining, in the scout image, a region of interest (ROI) corresponding to the at least one portion of the subject; and

determining, based on the ROI, the at least one scanning parameter associated with the at least one portion of the subject for performing the scanning by the imaging device, the at least one scanning parameter including a scanning direction of an axial scanning, wherein the determining, based on the ROI, the at least one scanning parameter, includes:

determining, based on coordinates of pixels in the ROI, a covariance matrix, the covariance matrix indicating a difference between pixels in the ROI in multiple pixel coordinates;

determining, based on the covariance matrix, one or more feature vectors associated with the multiple pixel coordinates;

determining, three feature vectors corresponding to top three highest eigenvalues in the multiple feature vectors, the three feature vectors corresponding to three candidate directions; and

determining, from the three candidate directions, a candidate direction as the scanning direction, the candidate direction forming a smallest angle with a horizontal axis direction among the three candidate directions.

2. The method of claim 1 , wherein the determining an ROI from the scout image includes:

segmenting the scout image using a target segmentation model.

3. The method of claim 2 , wherein the target segmentation model is a trained neural network model.

4. The method of claim 2 , wherein the target segmentation model is trained according to a training process, the training process comprising:

obtaining a plurality of training samples, each of the plurality of training samples including a sample scout image and a label associated with one or more sample regions segmented from the sample scout image; and

using the plurality of training samples to obtain the target segmentation model.

5. The method of claim 1 , wherein the at least one scanning parameter includes a scanning scope, and wherein the determining, based on the ROI, the at least one scanning parameter, further includes:

determining, based on a contour of the ROI, a frame encompassing the ROI; and

determining, based on the frame, the scanning scope associated with the ROI.

6. The method of claim 5 , wherein the determining, based on a contour of the ROI, a frame encompassing the ROI, includes:

generating, based on a plurality of points on the contour of the ROI, the frame encompassing the ROI.

7. The method of claim 6 , wherein the frame forms a minimum parallelogram encompassing the ROI and the determining, based on the frame, the scanning scope associated with the ROI includes:

determining, based on a thickness of a bone region of the subject, a translation distance of at least a portion of the frame;

obtaining an adjusted frame by adjusting at least a portion of the frame based on the translation distance; and

designating the adjusted frame as the scanning scope associated with the ROI.

8. The method of claim 1 , wherein the at least one scanning parameter further includes a scanning scope, and wherein the determining, based on the ROI, the at least one scanning parameter, further includes:

determining, based on the scanning direction and a contour of the ROI, the scanning scope associated with the ROI.

9. The method of claim 8 , wherein the determining, based on the scanning direction and a contour of the ROI, the scanning scope associated with the ROI, includes:

determining, based on the scanning direction, a plurality of feature points on the contour of the ROI;

determining a plurality of lines along the scanning direction, each of the plurality of lines passing through one of the plurality of feature points on the contour of the ROI; and

determining, based on the plurality of lines, a frame encompassing the ROI as the scanning scope associated with the ROI.

10. The method of claim 1 , further comprising:

obtaining a reference scanning parameter for each of the at least one scanning parameter associated with the ROI; and

determining whether a scanning parameter of the at least one scanning parameter needs to be adjusted by comparing the scanning parameter with the corresponding reference scanning parameter.

11. The method of claim 1 , wherein the scanning direction defines a tilting angle of a gantry of the imaging device or a direction along which the radiation beams or the pulses or radio waves are emitted.

12. A system for determining at least one scanning parameter for a scanning by an imaging device, comprising:

at least one non-transitory storage medium including a set of instructions; and

at least one processor in communication with the at least one non-transitory storage medium, wherein when executing the set of instructions, the at least one processor is configured to cause the system to:

obtain a scout image of at least one portion of a subject;

determine, in the scout image, a region of interest (ROI) corresponding to the at least one portion of the subject; and

determine, based on the ROI, the at least one scanning parameter associated with the at least one portion of the subject for performing the scanning by the imaging device, the at least one scanning parameter including a scanning direction of an axial scanning, wherein the determining, based on the ROI, the at least one scanning parameter, includes:

determining, based on coordinates of pixels in the ROI, a covariance matrix, the covariance matrix indicating a difference between pixels in the ROI in multiple pixel coordinates;

determining, based on the covariance matrix, one or more feature vectors associated with the multiple pixel coordinates;

determining, three feature vectors corresponding to top three highest eigenvalues in the multiple feature vectors, the three feature vectors corresponding to three candidate directions; and

determining, from the three candidate directions, a candidate direction as the scanning direction, the candidate direction forming a smallest angle with a horizontal axis direction among the three candidate directions.

13. The system of claim 12 , wherein the at least one scanning parameter includes a scanning scope, and wherein the determining, based on the ROI, the at least one scanning parameter, further includes:

determining, based on a contour of the ROI, a frame encompassing the ROI; and

determining, based on the frame, the scanning scope associated with the ROI.

14. The system of claim 13 , wherein the determining, based on a contour of the ROI, a frame encompassing the ROI, includes:

generating, based on a plurality of points on the contour of the ROI, the frame encompassing the ROI.

15. The system of claim 14 , wherein the determining, based on the frame, the scanning scope associated with the ROI includes:

obtaining an adjusted frame by adjusting at least a portion of the frame; and

designating the adjusted frame as the scanning scope associated with the ROI.

16. A method for evaluating a scanning parameter, implemented on a machine having at least one processor and a storage device, the method comprising:

obtaining a scout image of at least one portion of a subject;

determining, in the scout image, a region of interest (ROI) corresponding to the at least one portion of the subject;

determining, based on a contour of the ROI, a scanning parameter associated with the ROI, the scanning parameter including a scanning direction;

obtaining a reference scanning parameter associated with the ROI, wherein the reference scanning parameter includes a reference scanning direction; and

determining whether the scanning parameter needs to be adjusted by comparing the scanning parameter and the reference scanning parameter, including:

determining a reliability factor of the scanning direction based on a difference between the scanning direction and the reference scanning direction, and a pre-set reference error value of the scanning direction, the pre-set reference error value being an angle value determined according to a portion to be scanned by the imaging device; and

determining whether the scanning parameter needs to be adjusted based on the reliability factor of the scanning direction.

17. The method of claim 16 , wherein the determining, based on a contour of the ROI, a scanning parameter associated with the ROI, includes:

determining, in the scout image, a first reference region adjacent to the ROI using a target segmentation model; and

determining, based on the first reference region associated with the ROI, the scanning direction associated with the ROI.

18. The method of claim 17 , wherein the reference scanning parameter associated with the ROI includes a reference scanning direction associated with the ROI, and the obtaining a reference scanning parameter associated with the ROI, includes:

determining, in the scout image, a second reference region adjacent to the ROI or the first referent region using the target segmentation model;

determining, based on the first reference region and the second reference region associated with the ROI, the reference scanning direction associated with the ROI.

19. The method of claim 18 , wherein the determining the reference scanning direction associated with the ROI includes:

determining a first point on a contour of the second reference region;

determining, based on the first point on the contour of the second reference region, a second point on a contour of the first reference region, the second point being an intersection point of the contour of the first reference region and a feature line passing through the first point; and

determining, based on the second point and a third point on the contour of the first reference region, the reference scanning direction.

20. The method of claim 16 , wherein the scanning direction defines a tilting angle of a gantry of the imaging device or a direction along which the radiation beams or the pulses or radio waves are emitted.