Visualization of reflectors in intraluminal ultrasound images and associated systems, methods, and devices
Systems, methods, and devices for visualizing a reflector in a lumen of a patient are provided. In one embodiment, a system for visualizing a reflector includes an intraluminal ultrasound imaging catheter in communication with a processor circuit. The processor circuit is configured to receive, from the intraluminal ultrasound imaging catheter, ultrasound image signals representative of the lumen and the reflector, generate first ultrasound image data based on the ultrasound image signals, generate second ultrasound image data based on a portion of the ultrasound image signals associated with a second frequency different from the transmit frequency, and output a visualization based on the first and second ultrasound image data to a display. In some aspects, the visualization may serve to identify and distinguish nonlinear reflectors from linear reflectors in the combined image.
1 . An apparatus, comprising:
an intravascular imaging catheter comprising an imaging element; and
a processor circuit configured to be in communication with the intravascular imaging catheter, wherein the processor circuit is configured to:
receive intravascular image signals from the intravascular imaging catheter while positioned within a blood vessel, wherein a first portion of the intravascular image signals are representative of one or more linear reflectors and a second portion of the intravascular image signals are representative of one or more nonlinear reflectors, wherein the first portion of the intravascular image signals and the second portion of the intravascular image signals are obtained by the imaging element while positioned at a location along a length of the blood vessel,
generate a first intravascular image of the location, based on the first portion of the intravascular image signals;
generate a different, second intravascular image of the location, based on the second portion of the intravascular image signals;
determine a numerical value of a dimension in the second intravascular image such that the numerical value is determined based on the one or more nonlinear reflectors; and
provide, to a display in communication with the processor circuit, an output based on at least one of the first intravascular image or the second intravascular image, wherein the output comprises the numerical value of the dimension.
2 . The apparatus of claim 1 , wherein the numerical value of the dimension comprises at least one of a diameter of a stent, a size of a lumen, a size of a stenosis, or a diameter of a vessel wall.
3 . The apparatus of claim 1 , wherein the processor circuit is configured to perform an image processing operation on the second intravascular image before the numerical value of the dimension is determined.
4 . The apparatus of claim 3 , wherein the imaging processing operation is configured to identify a group of pixels in the second intravascular image that correspond to the one or more nonlinear reflectors.
5 . The apparatus of claim 4 , wherein the image processing operation comprises at least one of an erosion, a dilation, or a segmentation.
6 . The apparatus of claim 1 , wherein the processor circuit is configured to:
apply a first bandpass filter to the first portion of the intravascular image signals to generate the first intravascular image; and
apply a different, second bandpass filter to the second portion of the intravascular image signals to generate the second intravascular image.
7 . The apparatus of claim 6 ,
wherein the first bandpass filter is associated with a first frequency band and the second bandpass filter is associated with a second frequency band, and
wherein the second frequency band is higher than the first frequency band.
8 . The apparatus of claim 1 ,
wherein the processor circuit is configured to generate a composite image based on the first intravascular image and the second intravascular image,
wherein the output based on at least one of the first intravascular image or the second intravascular image comprises the composite image.
9 . The apparatus of claim 8 , wherein the processor circuit is configured to generate the composite image by overlaying the second intravascular image on the first intravascular image.
10 . The apparatus of claim 1 ,
wherein the first intravascular image is generated by a first processing thread, and
wherein the second intravascular image is generated by a second processing thread.