Apparatus and method for reconstructing subsurface electrophysiological patterns

Claim 1

An apparatus for recovering a pattern of cell generated electrical field potential U occurring at a specific time t and at a selected depth within a living organ from an associated pattern of electrical potential V at said specific time and at the surface of said living organ, said cell generated electrical field potential U having coordinates x', y' and being describable as U=U(x', y', y', t), said electrical potential V having coordinates x, y and being describable as V=V(x, y, t), said apparatus comprising: an electrode array for detecting values of V(x, y, t) at a plurality of points on the surface of said living organ, said points being spaced from each other by a distance determined by the expected spatial frequency of said electrical potential V(x, y, t); means for digitizing the detected values of V(x, y, t); and means for spatially deconvolving the digitized values of V(x, y, t) to recover the desired pattern of electrical field potential U(x', y', t) within said living organ, said deconvolving means including computing a transform function f z =f z (x-x', y-y'), said transform function having the value determined by an equation which describes the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value determined by the laws of conduction in the volume of said organ, and means for computing the product of said surface field potential V(x, y, t) and the inverse of said transform function to generate values of the electric field potential U(x', y', t).

Claim 2

An apparatus for recovering a pattern of cell generated electrical field potential U occurring at a specific time t and at a selected depth within a living organ from an associated pattern of electrical potential V at said specific time and at the surface of said living organ, said cell generated electrical field potential U having coordinates x', y' and being describable as U=U(x', y', y', t), said electrical potential V having coordinates x, y and being describable as V=V(x, y, t), said apparatus comprising: an electrode array for detecting values of V(x, y, t) at a plurality of points on the surface of said living organ, said points being spaced from each other by a distance determined by the expected spatial frequency of said electrical potential V(x, y, t); means for digitizing the detected values of V(x, y, t); and means for spatially deconvolving the digitized values of V(x, y, t) to recover the desired pattern of electrical field potential U(x', y', t) within said living organ, said deconvolving means including computing a transform function f z =f z (x-x', y-y'), said transform function having the value determined by an equation which describes the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value determined by the laws of conduction in the volume of said organ, and means for computing the product of said surface field potential V(x, y, t) and the inverse of said transform function to generate values of the electric field potential U(x', y', t).

Claim 5

An apparatus for recovering a pattern of cell generated electrical field potential U occurring at a specific time t and at a selected depth within a living organ from an associated pattern of electrical potential V at said specific time and at the surface of said living organ, said cell generated electrical field potential u having coordinates x', y' and being describable as U=U(x', y', t), said electrical potential V having coordinates x, y and being describable as V=V(x, y, t), said apparatus comprising: an array of electrodes, said array detecting an electric field potential signal at a plurality of points on the surface of said living organ, generating thereby said V(x, y, t) pattern, said points being spaced from each other by a distance determined by the expected spatial frequency of said electrical potential V(x, y, t); amplifier means attached to each said electrode in said electrode array for amplifying said detected signal; multiplexer means for sampling the output level of each said amplifier means and for outputting a time division multiplexed signal made up of such signal levels, said multiplexing being performed at a fast rate as compared with the rate of change of said electric field potential signals; analog to digital converter means for digitizing said multiplexer means output; means for controlling the operation of said multiplexer means and said analog to digital converter means, such that the output of said converter means is a plurality of digital words, each digital word reflecting the present analog level of electric field potential detected by a given electrode in said electode array; and processor means for storing said digital words until the signal outputs of each electrode in said array have been sampled and digitized, and for generating from this V(x, y, t) pattern of signals, by spatial deconvolution, a pattern of electrical potential U(x', y', t) occurring within said living organ, said spatial deconvolution being performed by computing a transform function f z =f z (x-x', y-y'), said transform function having the value determined by an equation which describes the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value determined by the laws of conduction in the volume of said organ, and means for computing the product of said surface field potential V(x, y, t) and the inverse of said transform function to generate values of the electric field potential U(x', y', t).

Claim 6

An apparatus for recovering a pattern of cell generated electrical field potential U occurring at a specific time t and at a selected depth within a living organ from an associated pattern of electrical potential V at said specific time and at the surface of said living organ, said cell generated electrical field potential u having coordinates x', y' and being describable as U=U(x', y', t), said electrical potential V having coordinates x, y and being describable as V=V(x, y, t), said apparatus comprising: an array of electrodes, said array detecting an electric field potential signal at a plurality of points on the surface of said living organ, generating thereby said V(x, y, t) pattern, said points being spaced from each other by a distance determined by the expected spatial frequency of said electrical potential V(x, y, t); amplifier means attached to each said electrode in said electrode array for amplifying said detected signal; multiplexer means for sampling the output level of each said amplifier means and for outputting a time division multiplexed signal made up of such signal levels, said multiplexing being performed at a fast rate as compared with the rate of change of said electric field potential signals; analog to digital converter means for digitizing said multiplexer means output; means for controlling the operation of said multiplexer means and said analog to digital converter means, such that the output of said converter means is a plurality of digital words, each digital word reflecting the present analog level of electric field potential detected by a given electrode in said electode array; and processor means for storing said digital words until the signal outputs of each electrode in said array have been sampled and digitized, and for generating from this V(x, y, t) pattern of signals, by spatial deconvolution, a pattern of electrical potential U(x', y', t) occurring within said living organ, said spatial deconvolution being performed by computing a transform function f z =f z (x-x', y-y'), said transform function having the value determined by an equation which describes the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value determined by the laws of conduction in the volume of said organ, and means for computing the product of said surface field potential V(x, y, t) and the inverse of said transform function to generate values of the electric field potential U(x', y', t).

Claim 12

An apparatus for recovering a pattern of cell generated electrical field potential U occurring at a specific time t and at a selected depth within a living organ from an associated pattern of electrical potential V at said specific time and the surface of said living organ, said cell generated electrical field potential u having coordinates x', y' and being describable as U=U(x', y', t), said electrical potential V having coordinates x, y and being describable as V=V(x, y, t), said apparatus comprising: a plurality of electrode arrays each detecting a separate pattern of electric field potential V(x, y, t) at a plurality of points on the surface of said living organ, said points being spaced from each other by a distance determined by the expected spatial frequency of said electrical potential V(x, y, t); amplifier means for amplifying the signal output of each electrode in each said electrode array; means for filtering said electric field potential signals, to eliminate frequency components therein outside of a selected band of frequency; means for digitizing the signals output from each said electrode array; means for spatially deconvolving the digitized signals, representing the pattern V(x, y, t) for each said electrode array, to recover the desired respective pattern of electrical potential U(x', y', t) within said living organ beneath such electrode array, said deconvolving means including computing a transform function f z =f z (x-x', y-y'), said transform function having the value determined by an equation which describes the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value determined by the laws of conduction in the volume of said organ, and means for computing the product of said surface field potential V(x, y, t) and the inverse of said transform function to generate values of the electric field potential U(x', y', t).

Claim 13

An apparatus for recovering a pattern of cell generated electrical field potential U occurring at a specific time t and at a selected depth within a living organ from an associated pattern of electrical potential V at said specific time and the surface of said living organ, said cell generated electrical field potential u having coordinates x', y' and being describable as U=U(x', y', t), said electrical potential V having coordinates x, y and being describable as V=V(x, y, t), said apparatus comprising: a plurality of electrode arrays each detecting a separate pattern of electric field potential V(x, y, t) at a plurality of points on the surface of said living organ, said points being spaced from each other by a distance determined by the expected spatial frequency of said electrical potential V(x, y, t); amplifier means for amplifying the signal output of each electrode in each said electrode array; means for filtering said electric field potential signals, to eliminate frequency components therein outside of a selected band of frequency; means for digitizing the signals output from each said electrode array; means for spatially deconvolving the digitized signals, representing the pattern V(x, y, t) for each said electrode array, to recover the desired respective pattern of electrical potential U(x', y', t) within said living organ beneath such electrode array, said deconvolving means including computing a transform function f z =f z (x-x', y-y'), said transform function having the value determined by an equation which describes the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value determined by the laws of conduction in the volume of said organ, and means for computing the product of said surface field potential V(x, y, t) and the inverse of said transform function to generate values of the electric field potential U(x', y', t).

Claim 14

An apparatus for recovering a pattern of electrical potential U(t) appearing within a living body from an associated pattern of electrical potential V(t) at the surface of said living body, comprising: an electrode array of N insulated electrodes for detecting V(t) at a plurality of points, each corresponding to a given electrode, on the surface of said living body; means for digitizing the detected values of V(t); and means for spatially deconvolving the digitized values of V(t) to recover the desired pattern of electrical potential U(t) within said living body, said means for spatially deconvolving comprising: means for computing an N×N matrix having values determined by linear simultaneous equations which describe the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value inversely related to its distance from such point; and means for computing the matrix product of V(t) as an N×1 column vector and the inverse of said N×N matrix to generate values of U(t) as an N×1 column vector.

Claim 15

An apparatus for recovering a pattern of electrical potential U(t) appearing within a living body from an associated pattern of electrical potential V(t) at the surface of said living body, comprising: an electrode array of N insulated electrodes for detecting V(t) at a plurality of points, each corresponding to a given electrode, on the surface of said living body; means for digitizing the detected values of V(t); and means for spatially deconvolving the digitized values of V(t) to recover the desired pattern of electrical potential U(t) within said living body, said means for spatially deconvolving comprising: means for computing an N×N matrix having values determined by linear simultaneous equations which describe the field potential at each of a plurality of subsurface points with respect to the field potential of each of a plurality of other selected sets of subsurface electric field potential generators, such that the potential at any one point is the sum of potentials from such surrounding generator sets, with each potential having a value inversely related to its distance from such point; and means for computing the matrix product of V(t) as an N×1 column vector and the inverse of said N×N matrix to generate values of U(t) as an N×1 column vector.