The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 15, 1993
Filed:
Oct. 24, 1990
Steven R Verdooner, Sacramento, CA (US);
Patricia C Meade, Esparto, CA (US);
Dennis J Makes, Sacramento, CA (US);
Ophthalmic Imaging Systems, Inc., Sacramento, CA (US);
Abstract
A novel optical subsystem is connected to an analyzing computer. The optical subsystem projects a grid of parallel lines onto a patient's retina, and a video camera in the optical subsystem captures a first retinal image and transmits it to the computer, where the image is digitized for analysis. A second image of the same eye is also captured, with the grid of parallel lines oriented perpendicular to the grid of the first image. The computer stores image data for the patient for a plurality of visits. The computer analyzes the images by forming a skeletonized topographical map of the retinal area of interest. First, a novel one-dimensional line detection algorithm is used to process the images. The line detection algorithm dilates, erodes and restores, Fourier transforms, bandpass filters, thresholds, skeletonizes, line traverses and interpolates the data for each of the two images. The resulting information is normalized to compensate for the effects of the patient's ocular optics. A topographic line map is constructed using the lines detected in the two images and the map is divided into sections for analysis. Using selected landmarks, the computer then registers the map with the topographic maps constructed from images acquired on previous patient visits. Volumetric changes in the topography of the retina as compared to the prior topographies for the patient are calculated, and, with other quantities of interest, are displayed in an easily-interpreted report.