Fluid flow rate detection device
View Patent ↗To provide a fluid flow rate detection device which can be evaluated as adequate from a medical point of view. The velocity of a fluid flowing through a luminal organ in vivo is to be obtained. V θ (r, θ)=w·V − θ +(1−w)·V + θ is calculated to obtain a calculated value V θ (r, θ) of the flow rate regarding a component of the fluid in the direction perpendicular to the ultrasonic beam direction. Here, the weight w is a value proportional to the distance d from the wall on one side of the organ at least when the distance is smaller than a predetermined distance from the wall on the one side, and the weight is a value proportional to the distance d′ from the wall on the other side of the organ at least when the distance is smaller than a predetermined distance from the wall on the one other side.
1. A fluid flow rate detection device comprising:
an ultrasonic probe which repeats operations to transmit/receive ultrasonic beams at a plurality of angular direction positions to/from a fluid flowing through a luminal organ in vivo, and to output an echo data array with respect to each ultrasonic beam;
a first calculation portion which calculates the flow rate regarding the ultrasonic beam direction component of the fluid, on the basis of the echo data array;
a detection portion which obtains B mode images of the luminal organ at a plurality of time points on the basis of the repeatedly obtained echo data arrays, and on the basis of the B mode images at the plurality of time points, detects motion velocities of the wall on one side and the wall on the other side of the luminal organ at a plurality of angular directions; and
a second calculation portion which obtains a first integral result V − θ as a calculated value of a flow rate regarding a component of the fluid in the direction perpendicular to the ultrasonic beam direction, the first integral result being obtained by integrating the equation of continuity relating to flow rate information regarding a component of the fluid in the direction perpendicular to the ultrasonic beam direction and flow rate information regarding a component of the fluid in the ultrasonic beam direction, from one side of the liminal organ to a position of interest (r, θ) at which a flow rate is to be obtained, using the motion velocity of the wall on the one side detected by the detection portion as a boundary condition for integration,
obtains a second integral result V + θ as a calculated value of a flow rate regarding a component of the fluid in the direction perpendicular to the ultrasonic beam direction, the second integral result being obtained by integrating the equation of continuity relating to the flow rate information regarding the component of the fluid in the direction perpendicular to the ultrasonic beam direction and the flow rate information regarding the component of the fluid in the ultrasonic beam direction, from the other side of the liminal organ to the position of interest (r, θ) at which a flow rate is to be obtained, using the motion velocity of the wall of the other side detected by the detection portion as a boundary condition for integration,
calculates V θ (r, θ)=w·V − θ +(1−w)·V + θ using the first integral result V − θ , the second integral result V + θ , and the weight w, to obtain a calculated value V θ (r, θ) as a flow rate regarding the component of the fluid in the direction perpendicular to the ultrasonic beam direction;
wherein the weight w is proportional to a distance d from the wall on the one side, at least until a predetermined distance from the wall on the one side, and is proportional to a distance d′ from the wall on the other side until a predetermined distance from the wall on the other side.
2. A fluid flow rate detection device according to claim 1 , wherein the weight w is a value in proportion to a distance d from the wall of the one side.