Abstract: A method of evaluating at least one tissue type includes providing a tissue classifier comprising multiple detector arrays for each of multiple tissue types. Each detector array comprises multiple detectors and each detector comprises multiple tissue type-assigned intravascular ultrasound (IVUS) spectra. For each of the detector arrays, an input IVUS spectrum of the tissue region is compared to the tissue type-assigned IVUS spectra of each of the detectors in the detector array and it is determined whether the input spectrum corresponds to the tissue type of the detector. The results for the detector. The results for the detector arrays are combined to provide a tissue characterization of the tissue region from the multiple tissue types. One or more IVUS images can be displayed with the tissue characterization and an indication of the size of at least one of the tissue types in a selected portion of the image that is displayed.

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: The field of the invention relates to medical imaging systems, and more particularly to systems and methods for estimating the size and position of a stent or other medical device within a patient. In one embodiment, a medical imaging system includes an elongated tubular member having distal and proximal ends, configured to be inserted into a vessel of a patient, an imaging device coupled to the distal end of the elongated tubular member, and a console electrically coupled to the imaging device, wherein the console includes a computer-usable medium, electrically coupled to the imaging device, having a sequence of instructions which, when executed by a processor, causes said processor to execute a process including generating an image of the vessel, and overlay one or more shapes onto the image age to provide a visual approximation of the size and position of a medical device to be applied within the patient.

Abstract: An improved method of tracking a catheter's position within a human body does not rely on x-rays, but instead calculates the position of the catheter's imaging head by analyzing image data. Such an analysis is able to determine the position of the imaging head in 3 dimensional space, relative to an arbitrarily selected reference image. An image is compared with the reference image, correlation data between corresponding points on the two images are gathered, and a correlation loss rate in a particular direction is determined. This correlation loss rate is modeled to an exponential function, which is evaluated to estimate an angle of separation between the image and the reference image. One or more angles of separation are used to determine a position in three dimensional space of the image, relative to the reference image. By repeating this process for a series of images being gathered by a catheter, the position of the catheter can be determined.

Abstract: Systems and methods are described for displaying classifier output and confidence measure in an image. The confidence measure advantageously provides additional information to the user indicating the accuracy of the classification result. Based on the classification accuracy, the user may accept or reject the classification result. In an exemplary embodiment, the classifier output is displayed on the image by color coding regions in the image based on their classifications. The confidence measure is displayed by adjusting the transparencies of the color coded regions according to their confidence measures. In one embodiment, only the classifications having confidence measures above a threshold are displayed. In other embodiments, the classifier output and confidence measure may be displayed separately, contour lines may be drawn through image regions having similar confidence measures, and the confidence measure may be displayed for a region under a pointer that the user can move within the image.

Abstract: The systems and methods described herein provide for fast and accurate image segmentation through the application of a multi-stage classifier to an image data set. An image processing system is provided having a processor configured to apply a multi-stage classifier to the image data set to identify a distinctive region. The multi-stage classifier can include two or more component classifiers. The first component classifier can have a sensitivity level configured to identify one or more target regions in the image data set and the second component classifier can have a specificity level configured to confirm the presence of the distinctive region in any identified target regions. Also provided is a classification array having multiple multi-stage classifiers for identification and confirmation of more than one distinctive region or for the application of different classification configurations to the image data set to identify a specific distinctive region.

Abstract: The systems and methods described herein allow measurement of the velocity of a pulse wave propagating within a body lumen using an intravascular elongate medical device. The elongate medical device can include a data collection device configured to collect pulse wave data at a location within the lumen. The data collection device is communicatively coupled with a velocity measurement system and configured to output the collected data to the velocity measurement system. The velocity measurement system is configured to calculate the velocity of the pulse wave based on the collection data. The velocity of a pulse wave over a region of the lumen can be used for tissue characterization, diagnosis and the like.

Abstract: The field of the invention relates to medical imaging systems, and more particularly to systems and methods for estimating the size and position of a stent or other medical device within a patient. In one embodiment, a medical imaging system includes an elongated tubular member having distal and proximal ends, configured to be inserted into a vessel of a patient, an imaging device coupled to the distal end of the elongated tubular member, and a console electrically coupled to the imaging device, wherein the console includes a computer-usable medium, electrically coupled to the imaging device, having a sequence of instructions which, when executed by a processor, causes said processor to execute a process including generating an image of the vessel, and overlay one or more shapes onto the image age to provide a visual approximation of the size and position of a medical device to be applied within the patient.

Abstract: The field of the invention relates to medical imaging systems, and more particularly to systems and methods for estimating the size and position of a stent or other medical device within a patient. In one embodiment, a medical imaging system includes an elongated tubular member having distal and proximal ends, configured to be inserted into a vessel of a patient, an imaging device coupled to the distal end of the elongated tubular member, and a console electrically coupled to the imaging device, wherein the console includes a computer-usable medium, electrically coupled to the imaging device, having a sequence of instructions which, when executed by a processor, causes said processor to execute a process including generating an image of the vessel, and overlay one or more shapes onto the image to provide a visual approximation of the size and position of a medical device to be applied within the patient.

Abstract: The systems and methods described herein provide for fast and accurate image segmentation through the application of a multi-stage classifier to an image data set. An image processing system is provided having a processor configured to apply a multi-stage classifier to the image data set to identify a distinctive region. The multi-stage classifier can include two or more component classifiers. The first component classifier can have a sensitivity level configured to identify one or more target regions in the image data set and the second component classifier can have a specificity level configured to confirm the presence of the distinctive region in any identified target regions. Also provided is a classification array having multiple multi-stage classifiers for identification and confirmation of more than one distinctive region or for the application of different classification configurations to the image data set to identify a specific distinctive region.

Abstract: A method for imaging patient tissue using an intravascular ultrasound image includes inserting a catheter into a patient blood vessel. The catheter includes at least one transducer configured and arranged for insertion into a lumen of the catheter. Acoustic signals are transmitted from the at least one transducer along a series of scan lines towards patient tissue between incremental rotations of the at least one transducer. The transmitted acoustic signals include first acoustic signals having first frequency bandwidths centered at a first center frequency and second acoustic signals having second frequency bandwidths centered at a second center frequency. Corresponding echo signals reflected from patient tissue are received, transformed, processed, and displayed.

Abstract: The systems and methods described herein provide for fast and accurate image segmentation through the application of a multi-stage classifier to an image data set. An image processing system is provided having a processor configured to apply a multi-stage classifier to the image data set to identify a distinctive region. The, multi-stage classifier can include two or more component classifiers. The first component classifier can have a sensitivity level configured to identify one or more target regions in the image data set and the second component classifier can have a specificity level configured to confirm the presence of the distinctive region in any identified target regions. Also provided is a classification array having multiple multi-stage classifiers for identification and confirmation of more than one distinctive region or for the application of different classification configurations to the image data set to identify a specific distinctive region.

Abstract: The field of the invention relates to medical imaging systems, and more particularly to systems and methods for estimating the size and position of a stent or other medical device within a patient. In one embodiment, a medical imaging system includes an elongated tubular member having distal and proximal ends, configured to be inserted into a vessel of a patient, an imaging device coupled to the distal end of the elongated tubular member and configured to emit one or more energy pulses and receive one or more echo signals, and a console electrically coupled to the imaging device, wherein the console includes a computer-usable medium, electrically coupled to the imaging device, having a sequence of instructions which, when executed by a processor, causes said processor to execute a process including generating an image of the vessel, and providing a graphical representation of a stent to be overlaid onto the image.

Abstract: The invention is generally directed to imaging systems, and more particularly to systems and methods for pattern recognition. In one embodiment, a medical imaging system includes an imaging device and a computer-usable medium, electrically coupled to the imaging device, having a sequence of instructions which, when executed by a processor, causes said processor to execute a process including generating an image from signals received by the imaging device, deconvolving the image, and then extracting a desired pattern from the deconvolved image.

Abstract: The systems and methods described herein provide for fast and accurate image segmentation through the application of a multi-stage classifier to an image data set. An image processing system is provided having a processor configured to apply a multi-stage classifier to the image data set to identify a distinctive region. The, multi-stage classifier can include two or more component classifiers. The first component classifier can have a sensitivity level configured to identify one or more target regions in the image data set and the second component classifier can have a specificity level configured to confirm the presence of the distinctive region in any identified target regions. Also provided is a classification array having multiple multi-stage classifiers for identification and confirmation of more than one distinctive region or for the application of different classification configurations to the image data set to identify a specific distinctive region.

Abstract: The systems and methods of the invention described herein improve classification accuracy by producing classifiers with individuality, in which each classifier exhibits its own distinctive behavior. A method according to one exemplary embodiment produces each classifier with individuality by randomly selecting subsets of a feature vector and using the randomly selected subsets of the feature vector in the design of the classifier. Because different subsets of the feature vector are used for each classifier, each classifier exhibits its own distinctive behavior or individuality. The classifiers with individuality improve classification accuracy, for example, when used as classifiers in a classifier array. This is because the individuality among the classifiers in the array ensures that a misclassification committed by one of the classifiers will not be repeated by other classifiers in the array, thereby improving the overall accuracy of the classifier array.

Abstract: The systems and methods described herein allow measurement of the velocity of a pulse wave propagating within a body lumen using an intravascular elongate medical device. The elongate medical device can include a data collection device configured to collect pulse wave data at a location within the lumen. The data collection device is communicatively coupled with a velocity measurement system and configured to output the collected data to the velocity measurement system. The velocity measurement system is configured to calculate the velocity of the pulse wave based on the collection data. The velocity of a pulse wave over a region of the lumen can be used for tissue characterization, diagnosis and the like.

Abstract: The systems and methods described herein provide for fast and accurate image segmentation through the application of a multi-stage classifier to an image data set. An image processing system is provided having a processor configured to apply a multi-stage classifier to the image data set to identify a distinctive region. The multi-stage classifier can include two or more component classifiers. The first component classifier can have a sensitivity level configured to identify one or more target regions in the image data set and the second component classifier can have a specificity level configured to confirm the presence of the distinctive region in any identified target regions. Also provided is a classification array having multiple multi-stage classifiers for identification and confirmation of more than one distinctive region or for the application of different classification configurations to the image data set to identify a specific distinctive region.

Abstract: The systems and methods described herein allow measurement of the velocity of a pulse wave propagating within a body lumen using an intravascular elongate medical device. The elongate medical device can include a data collection device configured to collect pulse wave data at a location within the lumen. The data collection device is communicatively coupled with a velocity measurement system and configured to output the collected data to the velocity measurement system. The velocity measurement system is configured to calculate the velocity of the pulse wave based on the collected data. The velocity of a pulse wave over a region of the lumen can be used for tissue characterization, diagnosis and the like.

Abstract: A method of evaluating at least one tissue type includes providing a tissue classifier comprising multiple detector arrays for each of multiple tissue types. Each detector array comprises multiple detectors and each detector comprises multiple tissue type-assigned intravascular ultrasound (IVUS) spectra. A plurality of the tissue type-assigned IVUS spectra of each detector correspond to a tissue type of the detector and a plurality of the tissue type-assigned IVUS spectra correspond to other tissue types. For each of the detector arrays, an input IVUS spectrum of the tissue region is compared to the tissue type-assigned IVUS spectra of each of the detectors in the detector array. For each of the detectors, it is determined whether the input spectrum corresponds to the tissue type of the detector based on the comparisons of the input spectrum to the tissue type-assigned spectra for that detector.