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Computer-vision-enabled augmented reality fundus biomicroscopy.

J W Berger·D S Shin
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Abstract

PURPOSE: To guide treatment for macular diseases and to facilitate real-time image measurement and comparison, investigations were initiated to permit overlay of previously stored photographic and angiographic images directly onto the real-time slit-lamp biomicroscopic fundus image. DESIGN: Experimental study in model eyes, and preliminary observations in human subjects. METHODS: A modified, binocular video slit lamp interfaced to a personal computer and framegrabber allows for image acquisition and rendering of stored images overlaid onto the real-time slit-lamp biomicroscopic fundus image. Development proceeds with rendering on a computer monitor, while construction is completed on a miniature display interfaced directly with one of the slit-lamp oculars. Registration and tracking are performed with in-house-developed software. MAIN OUTCOME MEASURES: Tracking speed and accuracy, ergonomic acceptability. RESULTS: Computer-vision algorithms permit robust montaging, tracking, registration, and rendering of previously stored photographic and angiographic images onto the real-time slit-lamp fundus biomicroscopic image. In model eyes and in preliminary studies in a human eye, optimized registration permits near-video-rate image overlay with updates at 3 to 10 Hz and misregistration errors on the order of 1 to 5 pixels. CONCLUSIONS: A prototype for ophthalmic augmented reality (image overlay) is presented. The current hardware/software implementation allows for robust performance.

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AlgorithmsChoroidal NeovascularizationFluorescein AngiographyFundus OculiHumansImage Processing, Computer-AssistedMacular DegenerationMicroscopyModels, AnatomicJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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J W Berger, D S Shin. 1999. Computer-vision-enabled augmented reality fundus biomicroscopy.. https://doi.org/10.1016/s0161-6420(99)90404-9

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