Ultrasound diagnosis apparatus and image processing apparatus

Abstract

An ultrasound diagnosis apparatus includes a calculating unit, an obtaining unit, a determining unit, and a controlling unit. By using a plurality of pieces of three-dimensional ultrasound image data in a time series corresponding to a three-dimensional region including a myocardium of a subject, the calculating unit calculates first movement information indicating a movement of the myocardium by tracking a movement of a region of interest that corresponds to the myocardium and that is set in each of the plurality of pieces of three-dimensional image data. The obtaining unit obtains direction information indicating a direction of a myocardial fiber in the myocardium. The determining unit determines second movement information indicating a movement of the myocardium with respect to the direction of the myocardial fiber, on the basis of the first movement information and the direction information. The controlling unit causes a display unit to display the second movement information.

What is claimed is: 
     
         1 . An ultrasound diagnosis apparatus comprising:
 a calculating unit configured to, by using a plurality of pieces of three-dimensional ultrasound image data in a time series corresponding to a three-dimensional region including a myocardium of a subject, calculate first movement information indicating a movement of the myocardium by tracking a movement of a region of interest that corresponds to the myocardium and that is set in each of the plurality of pieces of three-dimensional image data;   an obtaining unit configured to obtain direction information indicating a direction of a myocardial fiber in the myocardium;   a determining unit configured to determine second movement information indicating a movement of the myocardium with respect to the direction of the myocardial fiber, on a basis of the first movement information and the direction information; and   a controlling unit configured to cause a display unit to display the second movement information.   
     
     
         2 . The ultrasound diagnosis apparatus according to  claim 1 , wherein
 the obtaining unit estimates the direction information by using the first movement information, and   the determining unit determines the second movement information by using the direction information estimated by the obtaining unit.   
     
     
         3 . The ultrasound diagnosis apparatus according to  claim 2 , wherein the determining unit determines the direction information estimated by the obtaining unit to be the second movement information. 
     
     
         4 . The ultrasound diagnosis apparatus according to  claim 1 , wherein
 the obtaining unit obtains the direction information as information set by an operator, and   the determining unit extracts a movement component in the direction of the myocardial fiber from the first movement information by using the direction information set by the operator and determines the second movement information by using the extracted movement component.   
     
     
         5 . The ultrasound diagnosis apparatus according to  claim 1 , wherein
 while the direction information estimated by using the first movement information is referred to as first direction information, whereas the direction information obtained as information set by an operator is referred to as second direction information, the obtaining unit obtains third direction information indicating a direction of the myocardial fiber by using the first direction information and the second direction information, and   the determining unit determines the second movement information by using the third direction information.   
     
     
         6 . The ultrasound diagnosis apparatus according to  claim 5 , wherein
 the obtaining unit obtains the third direction information by smoothly switching from the first direction information to the second direction information in a boundary between predetermined spatiotemporal regions in the region of interest, and   the boundary between the predetermined spatiotemporal regions is a boundary between spatiotemporal regions in which a precision level in the estimation of the first direction information is degraded.   
     
     
         7 . The ultrasound diagnosis apparatus according to  claim 1 , wherein the region of interest is at least one boundary plane selected from an endocardial plane of the myocardium, an epicardial plane of the myocardium, and an intermediate layer plane of the myocardium. 
     
     
         8 . The ultrasound diagnosis apparatus according to  claim 2 , wherein the obtaining unit estimates the direction information by using a motion vector that is obtained as the first movement information, that is related to an individual tracking point structuring the region of interest, and that is obtained by performing a process including a three-dimensional pattern matching process performed by the calculating unit. 
     
     
         9 . The ultrasound diagnosis apparatus according to  claim 8 , wherein the obtaining unit obtains a projection component of the motion vector on a boundary plane serving as the region of interest and estimates the projection component as the direction information. 
     
     
         10 . The ultrasound diagnosis apparatus according to  claim 8 , wherein the obtaining unit obtains a partial translation movement component of a heart from a partial average motion vector in the region of interest and estimates the direction information by using a component obtained by subtracting the translation movement component from the motion vector. 
     
     
         11 . The ultrasound diagnosis apparatus according to  claim 8 , wherein the obtaining unit obtains local strain information of the region of interest from the first movement information and estimates the direction information by using the strain information and the motion vector near the region of interest. 
     
     
         12 . The ultrasound diagnosis apparatus according to  claim 2 , wherein, with respect to a temporal phase in which a magnitude of the direction information obtained by performing the estimating process is smaller than a predetermined threshold value, the obtaining unit estimates direction information indicating a direction of the myocardial fiber in the temporal phase by performing a temporal interpolation process. 
     
     
         13 . The ultrasound diagnosis apparatus according to  claim 8 , wherein
 the determining unit calculates at least one streamline obtained from at least one starting point set on a boundary plane serving as the region of interest in a vector field formed by the direction information on the boundary plane, by performing a spatial interpolation process on the vector field, and determines said at least one streamline as the second movement information, and   the controlling unit causes a line corresponding to said at least one streamline to be displayed while being superimposed on either three-dimensional rendering image data of the region of interest or a polar map of a heart.   
     
     
         14 . The ultrasound diagnosis apparatus according to  claim 8 , wherein
 the determining unit determines a direction of an individual vector in a vector field formed by the direction information on a boundary plane serving as the region of interest, to be the second movement information, and   the controlling unit causes either a line segment or an arrow indicating the direction of the individual vector and having a regulated length to be displayed while being superimposed on either three-dimensional rendering image data of the region of interest or a polar map of a heart.   
     
     
         15 . The ultrasound diagnosis apparatus according to  claim 8 , wherein, by using vector information of a projection component of the motion vector on a first boundary plane, the motion vector being obtained on the first boundary plane serving as the region of interest, and vector information of a projection component of the motion vector on a secondary boundary plane, the motion vector being obtained on the second boundary plane serving as the region of interest, the determining unit estimates either a shear strain rate or a shear strain between the first boundary plane and the second boundary plane and determines either information about the shear strain rate or information about the shear strain to be the second movement information. 
     
     
         16 . The ultrasound diagnosis apparatus according to  claim 1 , wherein the controlling unit causes an index related to a local wall movement in the region of interest to be displayed simultaneously, together with the second movement information. 
     
     
         17 . The ultrasound diagnosis apparatus according to  claim 1 , wherein
 when a plurality of regions of interest are each set as the region of interest, the obtaining unit obtains the direction information for each of the plurality of regions of interest,   the determining unit determines a piece of second movement information for each of the plurality of regions of interest, and   the controlling unit causes the pieces of second movement information corresponding to the plurality of regions of interest to be displayed simultaneously.   
     
     
         18 . The ultrasound diagnosis apparatus according to  claim 1 , wherein the determining unit determines a myocardial fiber angle that is an angle formed by the myocardial fiber and either a longitudinal direction of the myocardium or a circumferential direction of the myocardium, to be the second movement information. 
     
     
         19 . The ultrasound diagnosis apparatus according to  claim 1 , wherein the determining unit obtains a strain in the direction of the myocardial fiber by using the direction information and determines the obtained strain to be the second movement information. 
     
     
         20 . The ultrasound diagnosis apparatus according to  claim 2 , wherein the determining unit obtains a strain in the direction of the myocardial fiber by using a strain in a longitudinal direction and a strain in a circumferential direction that are obtained from the first movement information as local strains in the region of interest and determines the obtained strain to be the second movement information. 
     
     
         21 . The ultrasound diagnosis apparatus according to  claim 1 , wherein
 when a plurality of regions of interest are each set as the region of interest, the obtaining unit obtains the direction information for each of the plurality of regions of interest, and   the determining unit determines information obtained by calculating a difference between the regions of interest by using pieces of second movement information obtained for the plurality of regions of interest, to be new second movement information.   
     
     
         22 . The ultrasound diagnosis apparatus according to  claim 14 , wherein
 in addition to the direction of the individual vector in the vector field, the determining unit determines a myocardial fiber angle that is an angle formed by the myocardial fiber and either a longitudinal direction of the myocardium or a circumferential direction of the myocardium, to be the second movement information, and   the controlling unit changes a display mode of the line segment or the arrow in accordance with the myocardial fiber angle.   
     
     
         23 . An ultrasound diagnosis apparatus comprising:
 a calculating unit configured to, by using a plurality of pieces of three-dimensional ultrasound image data in a time series corresponding to a three-dimensional region including a myocardium of a subject, calculate first movement information indicating a movement of the myocardium by tracking a movement of a region of interest that is on a predetermined plane of the myocardium and that is set in each of the plurality of pieces of three-dimensional image data;   an obtaining unit configured to obtain vector information of a projection component of the movement in the region of interest on the predetermined plane of the myocardium, on a basis of the first movement information;   a determining unit configured to determine second movement information indicating a movement of the myocardium, on a basis of the vector information; and   a controlling unit configured to cause a display unit to display the second movement information.   
     
     
         24 . An image processing apparatus comprising:
 a calculating unit configured to, by using a plurality of pieces of three-dimensional ultrasound image data in a time series corresponding to a three-dimensional region including a myocardium of a subject, calculate first movement information indicating a movement of the myocardium by tracking a movement of a region of interest that corresponds to the myocardium and that is set in each of the plurality of pieces of three-dimensional image data;   an obtaining unit configured to obtain direction information indicating a direction of a myocardial fiber in the myocardium;   a determining unit configured to determine second movement information indicating a movement of the myocardium with respect to the direction of the myocardial fiber, on a basis of the first movement information and the direction information; and   a controlling unit configured to cause a display unit to display the second movement information.   
     
     
         25 . An image processing apparatus comprising:
 a calculating unit configured to, by using a plurality of pieces of three-dimensional ultrasound image data in a time series corresponding to a three-dimensional region including a myocardium of a subject, calculate first movement information indicating a movement of the myocardium by tracking a movement of a region of interest that is on a predetermined plane of the myocardium and that is set in each of the plurality of pieces of three-dimensional image data;   an obtaining unit configured to obtain vector information of a projection component of the movement in the region of interest on the predetermined plane of the myocardium, on a basis of the first movement information;   a determining unit configured to determine second movement information indicating a movement of the myocardium, on a basis of the vector information; and   a controlling unit configured to cause a display unit to display the second movement information.