Abstract: Regions-of-interest discovered from analyses of images obtained from one imaging modality can be further observed, analyzed, supplemented, and further analyzed by one or more additional imaging modalities and in an automated way. In addition, one or more pathologies identified from analyses of these regions-of-interest, and a metric of the likelihood of the presence of disease, and/or a metric of risk of disease progression can be derived therefrom.

Abstract: Methods for analyzing optical coherence tomography (OCT) images of the macula to reduce variance and improve disease diagnosis are presented. One embodiment of the invention is directed towards selecting analysis locations and data segmentation techniques to take advantage of structural homogeneities. Another embodiment is directed towards reducing the variance in a collection of normative data by transforming the individual members of the database to correspond to a Standard Macula. Variations in foveal size are corrected by radial transformation. Variations in layer thickness are corrected by axial shifting. Diagnosis is performed by comparing OCT images from a patient to the improved normative database.

Abstract: Methods for analyzing and visualizing OCT angiography data are presented. In one embodiment, an automated method for identifying the foveal avascular zone in a two dimensional en face image generated from motion contrast data is presented. Several 3D visualization techniques are presented including one in which a particular vessel is selected in a motion contrast image and all connected vessels are highlighted. A further embodiment includes a stereoscopic visualization method. In addition, a variety of metrics for characterizing OCT angiography image data are described.

Abstract: Systems, methods and applications for adjusting the imaging depth of a Fourier Domain optical coherence tomography system without impacting the axial resolution of the system are presented. One embodiment of the invention involves changing the sweep rate of a swept-source OCT system while maintaining the same data acquisition rate and spectral bandwidth of the source. Another embodiment involves changing the data acquisition rate of a SS-OCT system while maintaining the same sweep rate over the same spectral bandwidth. Several applications of variable imaging depth in the field of ophthalmic imaging are described.

Abstract: An imaging system (10) comprises at least one radiation detector (20) disposed adjacent a subject receiving aperture (18) to detect radiation from a subject, receive the radiation and generate measured data. An image processor (38) iteratively reconstructs the detected radiation into image representations, in each reconstruction iteration the image processor (38) applies noise reduction algorithms to at least a difference between the measured data and a portion of a previous iteration image representation.

Abstract: One embodiment of the present invention accounts for individual anatomical variation when evaluating optical nerve fiber measurements. In one aspect, contextual information is used to compensate or correct measurement data. In another aspect, reference coordinates are remapped for improved comparison or visualization. In one embodiment of this latter aspect, the method uses measurements of nerve fiber capacity and maps of nerve fiber retinal service to improve sensitivity and specificity in eye function metrics. In one instance, we use the birefringence of nerve fibers to determine the orientation of the fibers within the RNFL. Orientation of the fibers about the ONH is indicative of the service provided by the fibers and is used to improve the interpretation of thickness measurements of the nerve fiber layer. Normalized nerve fiber measurements about the optic nerve head improve specificity and sensitivity as compared to the standard model.

Abstract: An imaging system (10) includes at least one radiation detector (20) disposed adjacent a subject receiving aperture (18) to detect and measure at least one of emission and transmission radiation from a subject, the detector (20) at a plurality of projection angles. A processor (64) determines which radiation data belong to a field of view of the radiation detector (20) at each projection angle. An image processor (70, 72) iteratively reconstructs the radiation detected only in the determined field of view into image representations. Truncated data is compensated by supplying the untruncated data from the projections taken at different angles at which the truncated data is untruncated.

Abstract: One embodiment of the present invention accounts for individual anatomical variation when evaluating optical nerve fiber measurements. In one aspect, contextual information is used to compensate or correct measurement data. In another aspect, reference coordinates are remapped for improved comparison or visualization. In one embodiment of this latter aspect, the method uses measurements of nerve fiber capacity and maps of nerve fiber retinal service to improve sensitivity and specificity in eye function metrics. In one instance, we use the birefringence of nerve fibers to determine the orientation of the fibers within the RNFL. Orientation of the fibers about the ONH is indicative of the service provided by the fibers and is used to improve the interpretation of thickness measurements of the nerve fiber layer. Normalized nerve fiber measurements about the optic nerve head improve specificity and sensitivity as compared to the standard model.

Abstract: In an imaging method, estimated data is iteratively projected and backprojected. The iterative projecting and backprojecting includes projecting or backprojecting the estimated data along parallel paths each employing energy-dependent parameters appropriate for a different energy. During each iteration, the estimated data is adjusted based on comparison of the estimated data with measured data.

Abstract: One embodiment of the present invention accounts for individual anatomical variation when evaluating optical nerve fiber measurements. In one aspect, contextual information is used to compensate or correct measurement data. In another aspect, reference coordinates are remapped for improved comparison or visualization. In one embodiment of this latter aspect, the method uses measurements of nerve fiber capacity and maps of nerve fiber retinal service to improve sensitivity and specificity in eye function metrics. In one instance, we use the birefringence of nerve fibers to determine the orientation of the fibers within the RNFL. Orientation of the fibers about the ONH is indicative of the service provided by the fibers and is used to improve the interpretation of thickness measurements of the nerve fiber layer. Normalized nerve fiber measurements about the optic nerve head improve specificity and sensitivity as compared to the standard model.

Abstract: An imaging system (10) includes at least one radiation detector (20) disposed adjacent a subject receiving aperture (18) to detect and measure at least one of emission and transmission radiation from a subject, the detector (20) at a plurality of projection angles. A processor (64) determines which radiation data belong to a field of view of the radiation detector (20) at each projection angle. An image processor (70, 72) iteratively reconstructs the radiation detected only in the determined field of view into image representations. Truncated data is compensated by supplying the untruncated data from the projections taken at different angles at which the truncated data is untruncated.

Abstract: An imaging system (10) comprises at least one radiation detector (20) disposed adjacent a subject receiving aperture (18) to detect radiation from a subject, receive the radiation and generate measured data. An image processor (38) iteratively reconstructs the detected radiation into image representations, in each reconstruction iteration the image processor (38) applies noise reduction algorithms to at least a difference between the measured data and a portion of a previous iteration image representation.

Abstract: One embodiment of the present invention accounts for individual anatomical variation when evaluating optical nerve fiber measurements. In one aspect, contextual information is used to compensate or correct measurement data. In another aspect, reference coordinates are remapped for improved comparison or visualization. In one embodiment of this latter aspect, the method uses measurements of nerve fiber capacity and maps of nerve fiber retinal service to improve sensitivity and specificity in eye function metrics. In one instance, we use the birefringence of nerve fibers to determine the orientation of the fibers within the RNFL. Orientation of the fibers about the ONH is indicative of the service provided by the fibers and is used to improve the interpretation of thickness measurements of the nerve fiber layer. Normalized nerve fiber measurements about the optic nerve head improve specificity and sensitivity as compared to the standard model.

Abstract: In an imaging method, estimated data is iteratively projected and backprojected. The iterative projecting and backprojecting includes projecting or backprojecting the estimated data along parallel paths each employing energy-dependent parameters appropriate for a different energy. During each iteration, the estimated data is adjusted based on comparison of the estimated data with measured data.

Abstract: A diagnostic imaging system (20) comprising a computer workstation (26) for controlling the imaging system, interfacing with an operator and generating images. A coordinate system (100) is in data communication with the computer workstation. The coordinate system (100) is adapted to describe relative position of components in the diagnostic imaging system (20). A subject support (30) is describable within the coordinate system and an X-ray sub-system (22) is positionable around the subject support (30). Position sensors (44a) are operatively connected to the x-ray sub-system (22) and they provide signals to the workstation (26) indicative of the position of components of the x-ray sub-system (22) within the space represented by the coordinate system. A nuclear camera sub-system (24) is positionable around the subject support (30).

Abstract: A diagnostic imaging system (20) comprising a computer workstation (26) for controlling the imaging system, interfacing with an operator and generating images. A coordinate system (100) is in data communication with the computer workstation. The coordinate system (100) is adapted to describe relative position of components in the diagnostic imaging system (20). A subject support (30) is describable within the coordinate system and an X-ray sub-system (22) is positionable around the subject support (30). Position sensors (44a) are operatively connected to the x-ray sub-system (22) and they provide signals to the workstation (26) indicative of the position of components of the x-ray sub-system (22) within the space represented by the coordinate system. A nuclear camera sub-system (24) is positionable around the subject support (30).

Abstract: A gamma camera system and method are described which use multiple point sources to detect inaccuracies in detector translational and rotational alignment. In practice of the method of the preferred embodiment, three capillary tubes, each containing a drop of an isotope, are located in different planes and locations with respect to the axis of rotation of the detectors. A SPECT acquisition is performed and the point source projection data is processed to calculate the point source coordinates, from which center-of-rotation correction factors may be calculated. These correction factors are applied by mechanical and software adjustments to the gantry and acquisition systems of the camera to correct for both translational and rotational inaccuracies.

Abstract: A gamma camera system and method are described which use multiple point sources to detect inaccuracies in detector translational and rotational alignment. In practice of the method of the preferred embodiment, three capillary tubes, each containing a drop of an isotope, are located in different planes and locations with respect to the axis of rotation of the detectors. A SPECT acquisition is performed and the point source projection data is processed to calculate the point source coordinates, from which center-of-rotation correction factors may be calculated. These correction factors are applied by mechanical and software adjustments to the gantry and acquisition systems of the camera to correct for both translational and rotational inaccuracies.