Abstract: A method is disclosed for analyzing 3D image data generated from optical coherence tomography (OCT) systems. The first step in the method is to identify one or more surfaces within the 3D data set. The surfaces are then characterized using geometric primitives. Geometric primitives such as concavities, convexities, planar parts, saddles, and crevices can be used. In a preferred embodiment, the primitives are combined. Various pathological conditions of the eye can be evaluated based on any analysis of the primitives.

Abstract: An optical coherence tomography device is disclosed for improved imaging. Reduced levels of speckle in the images generated by the device are obtained by forming a B-scan from a plurality of A-scans, wherein each resolution cell of the B-scan is generated through compounding of a subset of the A-scans and wherein at least some of the subset of A-scans are separated by at least half the diameter of a speckle cell both tangent to and orthogonal to the B-scan at that cell.

Abstract: Techniques for collecting and processing complex OCT data to detect localized motion contrast information with enhanced accuracy and sensitivity are presented. In a preferred embodiment, vector differences between complex OCT signals taken at the same location on the sample are used to detect blood flow in the retina. Additional embodiments involving non-linear intensity weighting of the motion contrast information, normalization of the vector difference amplitudes, and calculating the absolute value of the standard deviation of Doppler signal are described. Image processing techniques to enhance the images resulting from these motion contrast techniques are also presented.

Abstract: Systems and methods for improving the assessment of disruption or abnormalities to retinal layers are presented. The disruptions are detected by analyzing at least one segmented boundary of optical coherence tomography data. Several different types of analysis can be used alone or in combination to make an assessment of the level of disruption to the particular boundary or layer defined by the boundary. The results can be presented as an end face image and quantified to report an amount of disruption. In one embodiment, a method for determining the disruption to the photoreceptor outer segment is described.

Abstract: A line scan imager is used to determine the motion of a subject. Each line of image data from the line scan imager is compared with a reference image. The location of a matching line in the reference image reveals the displacement of the subject. The current subject displacement can be determined based on each line of image data. The resulting displacement information can be used to correctly place other optical beams on the subject. The method can be applied to tracking the human eye to facilitate measurement, imaging, or treatment with a beam of optical radiation.

Abstract: Methods for relating ophthalmic structural measurements to ophthalmic function are presented. The central idea is that each value for a given structural measurement can be empirically associated with a certain likelihood of disability or reduced function by measuring relevant patient populations in which some subjects have those disabilities This method is intended as an aid to doctors who manage glaucoma, or for the study of glaucoma or glaucoma therapy in clinical trials. The method could also be used in other progressive diseases where more than one method is used to diagnose and manage disease, and it is desirable to use a structural method to predict the risk of further functional loss.

Abstract: Presented here are new processing techniques for optical coherence tomography (OCT) data that allow for improved visualization and use of full-range OCT images. These techniques minimize the central line artifact and the complex conjugate artifact without requiring additional system hardware or significantly increasing post-processing time. The central line artifact is minimized by normalizing each A-scan to account for ripples at the zero-delay position. The complex conjugate artifact is minimized by segmentation of a layer or layers that cross the zero-delay position, and in some embodiments by further segmentation of other surfaces based on the segmentation of the initial layer or layers. The segmentation information is then used to selectively attenuate the complex conjugate image. It may also be used for other purposes, such as dewarping.

Abstract: Systems and methods for efficiently displaying large volumes of medical imaging data using pre-defined dynamic displays to illustrate key anatomic features are described. In a preferred embodiment, one or more pulse files comprising en face images of sub sections of the volume are displayed sequentially to the user in a playback loop. These displays can aid in navigation of data for review and future data acquisition. Additional images generated from the data can be displayed next to or overlaid on the pulse files.

Abstract: Systems and methods for enhanced accuracy in optical coherence tomography imaging of the cornea are presented, including approaches for more accurate corneal surface modeling, pachymetry maps, keratometric values, and corneal power. These methods involve new scan patterns, an eye tracking mechanism for transverse motion feedback, and advanced motion correction algorithms. In one embodiment the methods comprise acquiring a first sparse set of data, using that data to create a corneal surface model, and then using the model to register a second set of denser data acquisition. This second set of data is used to create a more accurate, motion-corrected model of the cornea, from which pachymetry maps, keratometric values, and corneal power information can be generated. In addition, methods are presented for determining simulated keratometry values from optical coherence tomography data, and for better tracking and registration by using both rotation about three axes and the corneal apex.

Abstract: The present invention improves projection displays of volume data. Using the Minimum Intensity Projection (MinIP), fluid filled regions or other regions of hyporeflective tissue are displayed. By limiting the projection to partial volumes within the volume, differences in the scattering intensity within specific regions are isolated. In this way, hyperreflectivity of weakly scattering tissue can be assessed.