Topcon Medical Systems, Inc.

Alexandre Kotchkin

Yijun Huang

Tetsuyoshi Royama

Certain diseases of the retina are diagnosed by circular profile analysis of retinal parameters, such as thickness. Retinal thickness around a user-defined circle on the retina is measured by three-dimensional optical coherence tomography or other ophthalmological techniques. Abnormally thin regions are identified by comparing a measured function of thickness vs. polar angle to a reference function of thickness vs. polar angle. A degree of abnormality is characterized by the ratio of the integral of the measured thickness function to the integral of the reference thickness function over the abnormally thin region, as specified by a range of polar angles.

Characterization of retinal parameters by circular profile analysis

A second retinal characterization data set is mapped to a first retinal characterization dataset. The first retinal characterization dataset is displayed as a first graphical map. The second retinal characterization dataset is displayed as a second graphical map which is mapped to the first graphical map. The second graphical map may be warped and morphed onto the first graphical map. Retinal characterization datasets may be derived either from a fundus image or from a retinal parameter dataset calculated from a three-dimensional optical coherence tomography scan of a retina. Retinal parameter datasets may characterize parameters such as retinal thickness. In an embodiment, a fundus image is warped and morphed onto a retinal surface topographical map.

Mapping of retinal parameters from combined fundus image and three-dimensional optical coherence tomography

Certain diseases of the retina are diagnosed by circular profile analysis of retinal parameters, such as thickness. Retinal thickness around a user-defined circle on the retina is measured by various ophthalmological techniques and&#x2014;+mapped to a circular profile map. The circular profile map does not use segmentation of measurement data into arbitrary arcs, and thickness is mapped to a quasi-continuous range of display bands. The circular profile map is superimposed on a fundus image, or other two-dimensional image of the retina, allowing association of the circular profile map with the presence of blood vessels and other anatomical features. The simultaneous display of a series of circular profile maps generated from sets of measurement data taken at different times permits the ready visualization of the progression of retinal abnormalities.

Circular profile mapping and display of retinal parameters

Voxel data from a three-dimensional optical coherence tomography (3-D OCT) scan of a retina and pixel data from a two-dimensional (2-D) fundus image are spatially mapped. A 2-D composite image generated from the 3-D OCT data is spatially mapped to a fundus image using spatial indicia common to both images. The 3-D OCT data is then spatially mapped to the fundus image. An image processing system generates cross-correlated graphical representations of 3-D OCT data, subsets of 3-D OCT data, and a fundus image.

Method and apparatus for spatially mapping three-dimensional optical coherence tomography data with two-dimensional images

Disclosed are method and apparatus for mapping retinal thickness values to a movable measurement grid. A three-dimensional volume dataset acquired from three-dimensional optical coherence tomography is registered to a fundus image by rendering a two-dimensional composite image from the three-dimensional volume dataset and superimposing characteristic features in the two-dimensional composite image upon corresponding characteristic features in the fundus image. A measurement grid is displayed on the two-dimensional composite image. The measurement grid is moved to a region of interest, and retinal thickness values in the region of interest are mapped to sectors within the measurement grid.

Retinal thickness measurement by combined fundus image and three-dimensional optical coherence tomography

Disclosed are method and apparatus for characterizing the retinal nerve fiber layer (RNFL). An advantageous diagnostic parameter for characterizing the RNFL is a function of the product of the local RNFL thickness at a measurement locus&#xd7;the distance of the measurement locus from a base point. The value of the diagnostic parameter in a patient's retina is compared to a corresponding reference range acquired from a population of healthy retinas.

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Ridgewood, NJ, United States of America

Alexandre Kotchkin