Motion-based image segmentation systems and methods

An imaging system comprising:

• a catheter assembly including an intravascular imaging device having an imaging module configured to emit and receive energy at a first time to generate a first frame of image data and emit and receive energy at a second time that is different from the first time to generate a second frame of image data, wherein the image data represents a plurality of image elements;
• a user interface including an image display region;
• and
• an imaging engine in communication with the intravascular imaging device and the user interface and comprising at least one processor, the imaging engine being configured to:
• select, using the at least one processor, a first portion of the first frame, the first portion having a first subset of the image data of the first frame;
• compare, using the at least one processor, the selected first portion to image data of the second frame;
• select, using the at least one processor, a second portion of the second frame based on the comparison, the second portion having a second subset of the image data of the second frame;
• calculate, using the at least one processor, a first displacement vector representing relative movement between the first portion at the first time and the second portion at the second time;
• select, using the at least one processor, a third portion of the first frame, the third portion having a third subset of the image data of the first frame, and wherein the third subset of the image data of the first frame differs from the first subset of the image data of the first frame;
• compare, using the at least one processor, the selected third portion to image data of the second frame;
• select, using the at least one processor, a fourth portion of the second frame based on the comparison, the fourth portion having a fourth subset of the image data of the second frame;
• calculate, using the at least one processor, a second displacement vector representing relative movement between the third portion at the first time and the fourth portion at the second time;
• compare a length of the first displacement vector to a length of the second displacement vector;
• and
• based on the length of the first displacement vector differing from the length of the second displacement vector, determine that the first portion of the first frame of image data represents blood within a vessel lumen and the third portion of the first frame of image data represents vessel tissue or plaque.

A non-transitory computer-readable storage article having computer-executable instructions stored thereon to cause at least one programmable processor to:

• select a first portion of a first frame of image data, the first frame of image data representing a plurality of image elements generated at a first time, the first portion having a first subset of the image data of the first frame;
• compare the selected first portion to image data of a second frame of image data, the second frame of image data representing a plurality of image elements generated at a second time;
• select a second portion of the second frame based on the comparison, the second portion having a second subset of the image data of the second frame;
• calculate a first displacement vector representing relative movement between the first portion at the first time and the second portion at the second time;
• select a third portion of the first frame of image data, the third portion having a third subset of the image data of the first frame, and wherein the third subset of the image data of the first frame differs from the first subset of the image data of the first frame;
• compare the selected third portion to image data of the second frame;
• select a fourth portion of the second frame based on the comparison, the fourth portion having a fourth subset of the image data of the second frame;
• calculate a second displacement vector representing relative movement between the third portion at the first time and the fourth portion at the second time;
• compare a length of the first displacement vector to a length of the second displacement vector;
• based on the length of the first displacement vector differing from the length of the second displacement vector, determine that the first portion of the first frame of image data represents blood within a vessel lumen and the third portion of the first frame of image data represents vessel tissue or plaque;
• and
• position an indicator on an image at a location representing an interface between blood within the vessel lumen and vessel tissue or plaque.