Abstract: The present disclosure provides to process intravascular ultrasound (IVUS) images to identify key frames such as the proximal key frame, a distal key frame, and a minimal key frame from the IVUS images based on the raw lumen area, vessel area, and plaque burden. Ones of the key frames can be re-identified based on manipulation of other ones of the key frames.

Abstract: Methods include capturing intravascular ultrasound images. A drive motor is used to actively drive an ultrasound transducer at a set rotation speed. A temporary sensing window is created in which the ultrasound transducer is driven with a fixed drive signal. A plurality of signals from are received the ultrasound transducer during the temporary sensing window.

Abstract: Methods including methods for processing intravascular ultrasound images are disclosed. An example method may include collecting one or more ultrasound images of a blood vessel and segmenting the ultrasound images with a processor. Segmenting may include identifying one or more of a lumen border of the blood vessel and a media border for media within the blood vessel.

Abstract: Systems and methods for automatic lesion assessment and/or processing imaging data are disclosed. An example intravascular imaging system may include a catheter including an imaging device. A processor may be coupled to the catheter. The processor may be configured to process imaging data received from the imaging device. The processor may be configured to generate a longitudinal section view of a blood vessel from the imaging data received from the imaging device. The processor may be configured to identify a minimum lumen area along the longitudinal section view of the blood vessel, a distal reference point, and a proximal reference. A display unit may be coupled to the processor. The display unit may be configured to show a display including the longitudinal section view of the blood vessel.

Abstract: Intravascular imaging systems and methods for making and using intravascular imaging devices are disclosed. An example intravascular imaging device may comprise a catheter including an imaging device. A processor may be coupled to the catheter. The processor may be configured to process image data received from the imaging device. The processor may be configured to generate a calcium map. The calcium map may include an indicator of calcium depth to a vessel lumen surface, calcium distance to a center of the catheter, or both. A display unit may be coupled to the processor. The display unit may be configured to show a display including the calcium map.

Abstract: A balloon valvuloplasty catheter may include an elongate shaft having a guidewire lumen and a device lumen extending longitudinally therein, an expandable balloon secured to a distal portion of the elongate shaft, and an intravascular ultrasound catheter slidably disposed within the device lumen. The device lumen is in fluid communication with an interior of the expandable balloon. A method of preparing a native aortic heart valve of a patient's heart for transcatheter aortic valve replacement may include using the balloon valvuloplasty to observe via intravascular ultrasound and evaluate a position of the native leaflets relative to the left and right coronary artery ostia to determine if the native leaflets block the left coronary artery ostium and/or the right coronary artery ostium when the expandable balloon is inflated.

Abstract: A method for real-time displaying of cross-sectional images during an intravascular ultrasound (IVUS) imaging procedure includes, during an intravascular ultrasound imaging procedure, receiving electrical signals from at least one transducer in a catheter as the at least one transducer rotates and moves longitudinally along a lumen of a patient blood vessel; during the intravascular ultrasound imaging procedure, processing the received electrical signals to form a series of cross-sectional images that are longitudinally-offset from one another along a length of the lumen; during the intravascular ultrasound imaging procedure, concurrently displaying i) a most recent image and ii) a previous image that is either a) selected by the operator or b) automatically selected as having a maximum or minimum of a selected image characteristic; and, during the intravascular ultrasound imaging procedure, updating the display of the most recent image as a new image from the series of cross-sectional images is processed.

Abstract: A method for real-time displaying of cross-sectional images during an intravascular ultrasound (IVUS) imaging procedure includes, during an intravascular ultrasound imaging procedure, receiving electrical signals from at least one transducer in a catheter as the at least one transducer rotates and moves longitudinally along a lumen of a patient blood vessel; during the intravascular ultrasound imaging procedure, processing the received electrical signals to form a series of cross-sectional images that are longitudinally-offset from one another along a length of the lumen; during the intravascular ultrasound imaging procedure, concurrently displaying i) a most recent image and ii) a previous image that is either a) selected by the operator or b) automatically selected as having a maximum or minimum of a selected image characteristic; and, during the intravascular ultrasound imaging procedure, updating the display of the most recent image as a new image from the series of cross-sectional images is processed.

Abstract: A method for generating an ultrasound image includes receiving an image frame comprising consecutive ultrasound scan lines obtained using a rotating ultrasound imaging arrangement and determining at least a first cross-correlation value and a second cross-correlation value for each of a plurality of the scan lines. For each individual scan line of the plurality of scan lines, the first cross-correlation value comprises a cross-correlation coefficient between a first subframe comprising a plurality of consecutive scan lines including the individual scan line and a second subframe comprising a plurality of scan lines shifted from the first subframe by a first integer value. The second correlation value comprising a cross-correlation coefficient between the first subframe and a third subframe comprising a plurality scan lines shifted from the first subframe by a second integer value that is different from the first integer value.

Abstract: A method for generating a composite image using an intravascular imaging device includes receiving reflected echo signals from at least one transducer along a first of a plurality of radial scan lines. The received echo signals are passed through a plurality of signal processing channels to form a plurality of filtered signals. The filtered signals include a high-resolution tissue structure signal and at least one first pre-blood-flow-mask signal. High-resolution tissue structure signals are processed to form a high-resolution tissue structural image. First pre-blood-flow-mask signals are cross-correlated with second pre-blood-flow-mask signals from an adjacent radial scan line to form blood-flow-mask signals. Blood-flow-mask signals are processed to form a blood-flow mask.

Abstract: A medical imaging assembly includes an elongated catheter having a connector at the proximal end; an array of transducers on the distal end of the catheter; conductors electrically coupled to the array of transducers and in electrical communication with the connector of the catheter; and a control unit coupleable to the catheter to send and receive electrical signals between the control unit and the array of transducers through the connector of the catheter. The control unit has a processor to execute instructions including 1) selecting a first subset of M transmitting transducers and a second subset of N receiving transducers from the array of transducers, where N>M; and 2) for each of at least N transmit/receive cycles, a) directing the first subset of M transmitting transducers to transmit an acoustic signal; and b) directing the second subset of N receiving transducers to receive corresponding echo signals.

Abstract: A method for generating an ultrasound image includes receiving an image frame comprising consecutive ultrasound scan lines obtained using a rotating ultrasound imaging arrangement and determining at least a first cross-correlation value and a second cross-correlation value for each of a plurality of the scan lines. For each individual scan line of the plurality of scan lines, the first cross-correlation value comprises a cross-correlation coefficient between a first subframe comprising a plurality of consecutive scan lines including the individual scan line and a second subframe comprising a plurality of scan lines shifted from the first subframe by a first integer value. The second correlation value comprising a cross-correlation coefficient between the first subframe and a third subframe comprising a plurality scan lines shifted from the first subframe by a second integer value that is different from the first integer value.

Abstract: A method for real-time displaying of cross-sectional images during an intravascular ultrasound (IVUS) imaging procedure includes, during an intravascular ultrasound imaging procedure, receiving electrical signals from at least one transducer in a catheter as the at least one transducer rotates and moves longitudinally along a lumen of a patient blood vessel; during the intravascular ultrasound imaging procedure, processing the received electrical signals to form a series of cross-sectional images that are longitudinally-offset from one another along a length of the lumen; during the intravascular ultrasound imaging procedure, concurrently displaying i) a most recent image and ii) a previous image that is either a) selected by the operator or b) automatically selected as having a maximum or minimum of a selected image characteristic; and, during the intravascular ultrasound imaging procedure, updating the display of the most recent image as a new image from the series of cross-sectional images is processed.

Abstract: A method for generating an ultrasound image includes receiving an image frame having consecutive ultrasound scan lines obtained using a rotating ultrasound imaging arrangement and determining first and second cross-correlation values for a plurality of the scan lines. For each individual scan line, the first cross-correlation value includes a cross-correlation coefficient between a first subframe of consecutive scan lines including the individual scan line and a second subframe of scan lines shifted from the first subframe by a first integer value. The second correlation value includes a cross-correlation coefficient between the first subframe and a third subframe of scan lines shifted from the first subframe by a second integer value. The method further includes evaluating, individually for multiple scan lines, whether that scan line exhibits non-uniform rotation distortion using at least one of the first and second cross-correlation values. A correction for non-uniform rotation distortion is applied.

Abstract: A method for processing a sequence of ultrasound frames for display includes receiving a sequence of intravascular ultrasound (IVUS) frames of a vessel having a lumen, the sequence including a first frame and a second frame; determining one or more texture features for each of one or more regions of the first frame; determining at least one flow feature for each of the one or more regions by comparing the first and second frames; deriving a lumen border for the first frame using the one or more texture features and the at least one flow feature to characterize the one or more regions as within or outside of the lumen of the vessel; and displaying an ultrasound image of the first frame with the lumen border.

Abstract: A medical imaging assembly includes an elongated catheter having a connector at the proximal end; an array of transducers on the distal end of the catheter; conductors electrically coupled to the array of transducers and in electrical communication with the connector of the catheter; and a control unit coupleable to the catheter to send and receive electrical signals between the control unit and the array of transducers through the connector of the catheter. The control unit has a processor to execute instructions including 1) selecting a first subset of M transmitting transducers and a second subset of N receiving transducers from the array of transducers, where N>M; and 2) for each of at least N transmit/receive cycles, a) directing the first subset of M transmitting transducers to transmit an acoustic signal; and b) directing the second subset of N receiving transducers to receive corresponding echo signals.

Abstract: A method for generating a composite image using an intravascular imaging device includes receiving reflected echo signals from at least one transducer along a first of a plurality of radial scan lines. The received echo signals are passed through a plurality of signal processing channels to form a plurality of filtered signals. The filtered signals include a high-resolution tissue structure signal and at least one first pre-blood-flow-mask signal. High-resolution tissue structure signals are processed to form a high-resolution tissue structural image. First pre-blood-flow-mask signals are cross-correlated with second pre-blood-flow-mask signals from an adjacent radial scan line to form blood-flow-mask signals. Blood-flow-mask signals are processed to form a blood-flow mask.

Abstract: A method for generating a composite image using an intravascular imaging device includes receiving reflected echo signals from at least one transducer along a first of a plurality of radial scan lines. The received echo signals are passed through a plurality of signal processing channels to form a plurality of filtered signals. The filtered signals include a high-resolution tissue structure signal and at least one first pre-blood-flow-mask signal. High-resolution tissue structure signals are processed to form a high-resolution tissue structural image. First pre-blood-flow-mask signals are cross-correlated with second pre-blood-flow-mask signals from an adjacent radial scan line to form blood-flow-mask signals. Blood-flow-mask signals are processed to form a blood-flow mask.

Abstract: A method for generating a composite image using an intravascular imaging device includes receiving reflected echo signals from at least one transducer along a first of a plurality of radial scan lines. The received echo signals are passed through a plurality of signal processing channels to form a plurality of filtered signals. The filtered signals include a high-resolution tissue structure signal and at least one first pre-blood-flow-mask signal. High-resolution tissue structure signals are processed to form a high-resolution tissue structural image. First pre-blood-flow-mask signals are cross-correlated with second pre-blood-flow-mask signals from an adjacent radial scan line to form blood-flow-mask signals. Blood-flow-mask signals are processed to form a blood-flow mask.

Abstract: A method for generating an ultrasound image includes receiving an image frame having consecutive ultrasound scan lines obtained using a rotating ultrasound imaging arrangement and determining first and second cross-correlation values for a plurality of the scan lines. For each individual scan line, the first cross-correlation value includes a cross-correlation coefficient between a first subframe of consecutive scan lines including the individual scan line and a second subframe of scan lines shifted from the first subframe by a first integer value. The second correlation value includes a cross-correlation coefficient between the first subframe and a third subframe of scan lines shifted from the first subframe by a second integer value. The method further includes evaluating, individually for multiple scan lines, whether that scan line exhibits non-uniform rotation distortion using at least one of the first and second cross-correlation values. A correction for non-uniform rotation distortion is applied.