US 8,526,691 B2 · System and method for passive medical device navigation under real-time MRI guidance

Abstract

A method for tracking a needle along a path under real-time magnetic resonance imaging (MRI) guidance includes extracting a candidate needle artifact region from a plurality of incoming MR images of a needle inside biological tissue, determining an initial needle direction vector from the candidate needle artifact region in each of the plurality of incoming needle images, determining an initial needle base point from an intersection of the needle direction vector with a first incoming needle image, and an initial needle tip point from an intersection of the needle direction vector with a last incoming needle image, and tracking said needle by minimizing a cost function of the initial base point and initial direction vector to calculate an updated base point and updated direction vector. The updated base point and direction vector are used to visualize the advance of the needle along the path through the biological tissue.

Claims23

Dependent claims

A method for tracking a needle along a path under real-time magnetic resonance imaging (MRI) guidance, comprising the steps of:

extracting a candidate needle artifact region from a plurality of incoming MR images of a needle inside biological tissue;
determining an initial needle direction vector from the candidate needle artifact region in each of the plurality of incoming needle images;
determining an initial needle base point from an intersection of the needle direction vector with a first incoming needle image, and an initial needle tip point from an intersection of the needle direction vector with a last incoming needle image;
and
tracking said needle by minimizing a cost function of the initial base point and initial direction vector to calculate an updated base point and updated direction vector, wherein the updated base point and direction vector are used to visualize the advance of the needle along the path through the biological tissue.

2 more elements

A method for tracking a needle along a path under real-time magnetic resonance imaging (MRI) guidance, comprising the steps of:

determining an initial base point and an initial direction vector of a needle during an MRI guided intervention by analyzing a needle artifact region in each of a plurality of incoming MR images;
and
tracking said needle during said intervention by minimizing a cost function of the initial base point and initial direction vector to calculate an updated base point and updated direction vector, wherein said cost function of the base point and direction vector is given by
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wherein base point b=(bx, by, bz)TεR3, direction vector d=(dx, dy, dz)TεR3, xi is the position of pixel i, Ii is the image intensity for pixel i, N is the number of pixels, wk is given by
wk(k(x,b,d))=H(k(x,b,d))H(1−k(x,b,d)),
where H is the Heaviside step function and k is given by
k
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wl is given by
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wherein l is given by
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p(x,b,d)=b+k(x,b,d)dεR3, and N(x, μ, σ) denotes the probability density function for a univariate normal distribution with the mean μ and standard deviation σ, wherein the updated base point and direction vector are used to advance the needle along the path through biological tissue.

169 more elements

A program storage device readable by a computer, tangibly embodying a program of instructions executable by the computer to perform the method steps for tracking a needle along a path under real-time magnetic resonance imaging (MRI) guidance, the method comprising the steps of:

extracting a candidate needle artifact region from a plurality of incoming MR images of a needle inside biological tissue;
determining an initial needle direction vector from the candidate needle artifact region in each of the plurality of incoming needle images;
determining an initial needle base point from an intersection of the needle direction vector with a first incoming needle image, and an initial needle tip point from an intersection of the needle direction vector with a last incoming needle image;
and
tracking said needle by minimizing a cost function of the initial base point and initial direction vector to calculate an updated base point and updated direction vector, wherein the updated base point and direction vector are used to visualize the advance of the needle along the path through the biological tissue.

2 more elements

Dependencies are inferred from the claim text.

System and method for passive medical device navigation under real-time MRI guidance

Life of this patent

System and method for passive medical device navigation under real-time MRI guidance

Life of this patent

Abstract

Claims23