Intravascular ultrasound enhanced image and signal processing

An apparatus for performing an intravascular ultrasound imaging via an ultrasound signal transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals;
• an arrangement for deriving successive sets of ultrasound signals from the plurality of ultrasound signals;
• an arrangement for deriving a plurality of successive images from the successive sets of ultrasound signals;
• and
• an arrangement for monitoring for a change in corresponding pixel values belonging to successive images in the plurality of images.

An apparatus for performing an intravascular ultrasound imaging via an ultrasound signal transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals;
• an arrangement for deriving successive sets of ultrasound signals from the plurality of ultrasound signals;
• an arrangement for deriving a plurality of successive images from the successive sets of ultrasound signals;
• an arrangement for evaluating each pair of successive images;
• and
• an arrangement for deriving a closeness function, wherein:
• for each pair of successive images, the arrangement for evaluating includes an arrangement for performing a closeness operation between a first image of the pair of images and a second image of the pair of images, and
• each value of the closeness function is a result of the performed closeness operation.

An apparatus for performing an intravascular ultrasound imaging via an ultrasound signal transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals;
• an arrangement for deriving successive sets of ultrasound signals from the plurality of ultrasound signals;
• an arrangement for deriving a plurality of successive images from the successive sets of ultrasound signals;
• and
• an arrangement for performing a shift evaluation for each image in relation to a predecessor image in order to monitor each one of the successive images for a vasomotion of the bodily lumen.

An apparatus for performing an intravascular ultrasound imaging via an ultrasound signal transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals;
• an arrangement for deriving a plurality of images from the plurality of detected ultrasound signals;
• an arrangement for performing a shift evaluation for each image in relation to a predecessor image;
• an arrangement for monitoring for a change in corresponding pixel values belonging to successive images in the plurality of images;
• an arrangement for monitoring cardiovascular periodicity;
• and
• an arrangement for stabilizing each image of the plurality of images in relation to the predecessor image.

An apparatus for performing an intravascular ultrasound imaging via an ultrasound signal transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for moving the ultrasound signal transmitter and detector through a section of the bodily vessel;
• an arrangement for detecting ultrasound signals;
• an arrangement for deriving a first image from ultrasound signals detected during a first movement of the ultrasound signal transmitter and detector through the vessel;
• an arrangement for deriving a second image from ultrasound signals detected during a second movement of the ultrasound signal transmitter and detector through the vessel;
• an arrangement for performing a shift evaluation and a stabilization on the second image in relation to the first image;
• and
• an arrangement for displaying the stabilized second image.

An apparatus for performing an intravascular ultrasound imaging via an ultrasound signal transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for moving the ultrasound signal transmitter and detector through a section of the bodily vessel;
• an arrangement for detecting ultrasound signals;
• an arrangement for deriving a first image from ultrasound signals detected from a first portion of the vessel;
• an arrangement for deriving a second image from ultrasound signals detected from a second portion of the vessel;
• an arrangement for performing a shift evaluation and a stabilization on the second image in relation to the first image;
• and
• an arrangement for displaying the stabilized second image.

An apparatus for performing an intravascular ultrasound imaging via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for performing a first movement of the ultrasound signal transmitter and detector along a first section of the vessel;
• an arrangement for detecting a first set of ultrasound signals;
• an arrangement for deriving a first series of successive images from the first set of detected ultrasound signals;
• an arrangement for performing a second movement of the ultrasound signal transmitter and detector along a second section of the vessel;
• an arrangement for detecting a second set of ultrasound signals;
• an arrangement for deriving a second series of successive images from the second set of detected ultrasound signals;
• an arrangement for selecting from the second series of successive images a subgroup of successive images formed as a reference segment;
• an arrangement for performing a closeness operation between each image of the reference segment and each image of a plurality of subgroups of images derived from the first series of successive images;
• and
• an arrangement for matching each image of the reference segment to each image of another subgroup of the plurality of subgroups, the other subgroup being a matched segment.

An apparatus for performing an IVUS imaging operation via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals reflected from at least a portion of the bodily lumen;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the plurality of reflected ultrasound signals in order to produce at least a first set of digitized samples and a second set of digitized samples;
• an arrangement for deriving from the first set of digitized samples a first two dimensional array including a set of data, wherein:
• the first two dimensional array includes a first plurality of elements, each of the first plurality of elements representing a digitized sample corresponding to one of the plurality of reflected ultrasound signals from a predetermined spatial location of the bodily lumen, the set of data of the first two dimensional array representing a complete cross section of the bodily lumen,
• the first two dimensional array is configured in polar coordinates,
• a first axis of the first two dimensional array represents an r coordinate, and
• a second axis of the first two dimensional array represents an angular coordinate;
• an arrangement for deriving from the second set of digitized samples a second two dimensional array including a set of data, wherein:
• the second two dimensional array includes a second plurality of elements, each of the second plurality of elements representing a digitized sample corresponding to one of the plurality of reflected ultrasound signals from the predetermined spatial location,
• the set of data of the second two dimensional array represents the complete cross section of the bodily lumen,
• the second two dimensional array is configured in polar coordinates,
• a first axis of the second two dimensional array represents the r coordinate,
• a second axis of the second two dimensional array axis represents the angular coordinate;
• an arrangement for performing a shift evaluation and detection operation of the second two dimensional array with respect to the first two dimensional array in order to detect a magnitude and a direction of at least one of a global vasomotion and a rigid rotation represented by the set of data corresponding to the second two dimensional array in relation to the set of data corresponding to the first two dimensional array;
• and
• an arrangement for stabilizing the second two dimensional array by applying a shift having a selected magnitude and a selected direction to the second two dimensional array in order to uniformly shift along at least one of the first axis and the second axis of the second two dimensional array each of the second plurality of elements according to the selected magnitude and the selected direction, the stabilizing arrangement providing a compensation for at least one of the rigid rotation and the global vasomotion, wherein the selected magnitude and the selected shift direction are derived from the shift evaluation and detection operation.

An apparatus for performing an IVUS imaging operation via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals reflected from at least a portion of the bodily lumen;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the plurality of reflected ultrasound signals in order to produce at least a first set of digitized samples and a second set of digitized samples;
• an arrangement for deriving from the first set of digitized samples a first two dimensional array including a set of data, wherein:
• the first two dimensional array includes a first plurality of elements, each of the first plurality of elements representing a digitized sample corresponding to one of the plurality of reflected ultrasound signals from a predetermined spatial location of the bodily lumen, the set of data of the first two dimensional array representing a complete cross section of the bodily lumen,
• the first two dimensional array is configured in Cartesian coordinates,
• a first axis of the first two dimensional array represents an X coordinate, and
• a second axis of the first two dimensional array represents a Y coordinate;
• an arrangement for deriving from the second set of digitized samples a second two dimensional array including a set of data, wherein:
• the second two dimensional array includes a second plurality of elements, each of the second plurality of elements representing a digitized sample corresponding to one of the plurality of reflected ultrasound signals from the predetermined spatial location,
• the set of data of the second two dimensional array represents the complete cross section of the bodily lumen,
• the second two dimensional array is configured in Cartesian coordinates,
• a first axis of the second two dimensional array represents the X coordinate, and
• a second axis of the second two dimensional array axis represents the Y coordinate;
• an arrangement for performing a shift evaluation and detection operation of the second two dimensional array with respect to the first two dimensional array in order to detect a magnitude and a direction of a rigid Cartesian displacement along at least one of the X coordinate and the Y coordinate represented by the set of data corresponding to the second two dimensional array in relation to the set of data corresponding to first two dimensional array;
• and
• an arrangement for stabilizing the second two dimensional array by applying a shift having a selected magnitude and a selected direction to the second two dimensional array in order to uniformly shift along at least one of the first axis and the second axis of the second two dimensional array each of the second plurality of elements according to the selected magnitude and the selected direction, the stabilizing arrangement providing a compensation for the rigid Cartesian displacement, wherein the selected magnitude and the selected direction are derived from the shift evaluation and detection operation.

An apparatus for forming and processing a closeness function via an ultrasound transmitter and detector capable of being placed within a bodily lumen in order to monitor a cardiovascular periodicity from an IVUS imaging operation, comprising:

• an arrangement for detecting a plurality of ultrasound signals reflected from at least a portion of the bodily lumen;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the plurality of reflected ultrasound signals in order to produce at least a first plurality of successive frames, each frame including a set of data, wherein:
• each frame includes a plurality of elements,
• each one of the plurality of elements represents a digitized sample corresponding to one of the plurality of reflected ultrasound signals from a predetermined spatial location of the bodily lumen,
• the set of data corresponding to each one of the plurality of frames representing a complete cross section of the bodily lumen, and
• each one of the plurality of frames is configured in at least one of Cartesian coordinates and polar coordinates;
• an arrangement for providing a one dimensional function formed as a closeness function, wherein a value of the closeness function corresponding to f(n), n being a positive integer, is determined by a closeness operation performed between elements stored in the nth frame and between elements stored in the nth+1 frame;
• and
• an arrangement for processing the closeness function in order to derive a magnitude of a periodicity of the closeness function.

An apparatus for automatically segmenting an IVUS image via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals reflected from at least a portion of the bodily lumen;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the plurality of reflected ultrasound signals in order to produce a plurality of sets of digitized samples;
• an arrangement for deriving a plurality of successive frames from the plurality of sets of digitized samples, wherein:
• each frame includes a plurality of pixels;
• each pixel represents one of the plurality of digitized samples corresponding to one of the plurality of reflected ultrasound signals from a predetermined spatial location of the bodily lumen, each frame representing a complete cross section of the bodily lumen, and
• each frame is configured in at least one of polar coordinates and Cartesian coordinates;
• an arrangement for assigning one of a plurality of textural categories to each pixel included in each frame based on a relationship of each pixel with an adjacent pixel, each assigned textural category being derived from the corresponding pixel being one of higher than, lower than, and equal to in value with respect to each closest adjacent pixel;
• an arrangement for detecting a change in the assigned textural category of each pixel by monitoring the textural category assigned to each pixel included in each one of the plurality of frames;
• and
• an arrangement for producing a binary frame including:
• an arrangement for classifying each pixel corresponding to a selected one of the plurality frames into one of a first class and a second class, and
• an arrangement for assigning a binary value to each pixel corresponding to the selected frame, wherein the first class indicates an absence of a change in the textural category assigned to the associated pixel, and wherein the second class indicates a presence of a change in the textural category assigned to the associated pixel.

An apparatus for enhancing a quality of an IVUS imaging operation via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals reflected from at least a portion of the bodily lumen;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the plurality of reflected ultrasound signals in order to produce a plurality of sets of digitized samples;
• an arrangement for deriving a plurality of successive frames from the plurality of sets of digitized samples, wherein:
• each frame includes a plurality of pixels,
• each pixel represents one of the plurality of digitized samples corresponding to one of the plurality of reflected ultrasound signals from a predetermined spatial location of the bodily lumen, each frame representing a complete cross section of the bodily lumen, and
• each frame is configured in at least one of polar coordinates and Cartesian coordinates;
• an arrangement for deriving a first difference frame having a plurality of pixels, each pixel of the first difference frame including a pixel value, wherein each pixel value corresponds to a sum of absolute differences between pixels included in a first frame of the plurality of frames and between corresponding pixels included in a second frame of the plurality of frames;
• an arrangement for deriving a second difference frame having a plurality of pixels, each pixel of the second difference frame including a pixel value, wherein each pixel value of each pixel of the second difference frame corresponds to the sum of absolute differences between pixels included in the second frame of the plurality of frames and between corresponding pixels included in a third frame of the plurality of frames;
• an arrangement for deriving a maximum value frame having a plurality of pixels, each pixel of the maximum value frame including a pixel value, wherein each pixel value of each pixel of the maximum value frame corresponds to a maximum value selected between the pixel value of each pixel of the first difference frame and the pixel value of each corresponding pixel of the second difference frame;
• an arrangement for deriving a first mask frame by applying a normalization operation to the maximum value frame, wherein the normalization operation includes an arrangement for dividing the pixel value of each pixel of the maximum value frame by the pixel value of the pixel in the maximum value frame having the highest pixel value in the maximum value frame;
• an arrangement for deriving a second mask frame including:
• an arrangement for raising each pixel value of the first mask frame to a power, and
• an arrangement for subtracting each raised pixel value from the value of 1;
• an arrangement for deriving an enhanced frame by multiplying each pixel value of a selected one of the plurality of frames by a corresponding pixel value of the second mask frame;
• and
• an arrangement for displaying an image corresponding to the enhanced frame.

A apparatus for performing an automatic matching operation with respect to an IVUS imaging operation via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for moving each of the ultrasound signal transmitter and the ultrasound signal detector along a length of a first segment of the bodily vessel;
• an arrangement for detecting a first plurality of ultrasound signals reflected from at least a portion of the bodily vessel;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the first plurality of reflected ultrasound signals in order to produce a first plurality of sets of digitized samples;
• an arrangement for deriving a first plurality of successive frames for a first pullback film from the first plurality of sets of digitized samples, wherein:
• each frame includes a first plurality of elements,
• each element represents one of the first plurality of digitized samples corresponding to one of the first plurality of reflected ultrasound signals from a first predetermined spatial location of the bodily vessel, each frame representing a complete cross section of the bodily vessel, and
• each frame is configured in at least one of polar coordinates and Cartesian coordinates;
• an arrangement for moving each of the ultrasound signal transmitter and the ultrasound signal detector along a length of a second segment of the bodily vessel, the second segment substantially overlapping the first segment;
• an arrangement for detecting a second plurality of ultrasound signals reflected from at least a portion of the bodily vessel;
• an arrangement for processing and digitizing a second set of ultrasound signals obtained from the second plurality of reflected ultrasound signals in order to produce a second plurality of sets of digitized samples;
• an arrangement for deriving a second plurality of successive frames for a second pullback film from the second plurality of sets of digitized samples, wherein:
• each frame of the second plurality of successive frames includes a second plurality of elements,
• each element of the second plurality of elements represents one of the second plurality of digitized samples corresponding to one of the second plurality of reflected ultrasound signals from a second predetermined spatial location of the bodily vessel, each frame of the second plurality of successive frames representing the complete cross section of the bodily vessel, and
• each frame of the second plurality of successive frames is configured in at least one of polar coordinates and Cartesian coordinates;
• an arrangement for selecting as a reference segment a subset of successive frames from the second pullback film, the reference segment representing a section of the bodily vessel also represented by a subset of successive frames derived from the first pullback film and formed as a second segment;
• and
• an arrangement for automatically matching between the reference segment and the second segment by performing closeness operations between frames of the first pullback film and frames of the reference segment.

An apparatus for monitoring a local vasomotion of a blood vessel via an ultrasound transmitter and detector capable of being placed within a bodily lumen, comprising:

• an arrangement for detecting a plurality of ultrasound signals reflected from at least a portion of the blood vessel;
• an arrangement for processing and digitizing a first set of ultrasound signals obtained from the plurality of reflected ultrasound signals in order to produce at least a first set of digitized samples and a second set of digitized samples;
• an arrangement for deriving from the first set of digitized samples a first two dimensional array including a set of data, wherein:
• the first two dimensional array includes a first plurality of elements, each of the first plurality of elements representing a digitized sample corresponding to one of the plurality of reflected ultrasound signals from a predetermined spatial location of the bodily vessel, the set of data of the first two dimensional array representing a complete cross section of the blood vessel,
• the first two dimensional array is configured in polar vectors,
• a first axis of the first two dimensional array represents an r coordinate, and
• a second axis of the first two dimensional array represents an angular coordinate;
• an arrangement for deriving from the second set of digitized samples a second two dimensional array including a set of data, wherein:
• the second two dimensional array includes a second plurality of elements, each of the second plurality of elements representing a digitized sample corresponding to one of the plurality of reflected ultrasound signals from the predetermined spatial location,
• the set of data of the second two dimensional array represents the complete cross section of the blood vessel,
• the second two dimensional array is configured in polar vectors,
• a first axis of the second two dimensional array represents the r coordinate,
• a second axis of the second two dimensional array axis represents the angular coordinate;
• and
• an arrangement for detecting a magnitude and a direction of the local vasomotion by applying a plurality of one dimensional shifts on the set of data of each polar vector of the second two dimensional array and by applying a closeness operation between the shifted set of data of each polar vector of the second two dimensional array and between the set of data of each corresponding polar vector of the first two dimensional array.