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New objective classification system for nuclear opacification.

D D Duncan·O B Shukla·S K West·O D Schein
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Abstract

We have developed an autonomous objective classification scheme for degree of nuclear opacification. The algorithm was developed by using a series of color 35-mm slides acquired with a Topcon photo slit-lamp microscope and use of standard camera settings. The photographs were digitized, and first, and second-order gray-level statistics were extracted from within circular regions of the nucleus. Classifications of severity were performed by using these features as input to a neural network. Training versus classification performance was tested by using photographs of different eyes, and test/retest classification reproducibility was evaluated by using paired photographs of the same eyes. We demonstrate good performance of the classifier against subjective assessments rendered by the Wilmer grading system [Invest. Ophthalmol. Visual Sci. 29, 73 (1988)] and markedly better test/retest reproducibility.

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AlgorithmsCataractHumansImage Processing, Computer-AssistedModels, BiologicalPhotographyReproducibility of ResultsSeverity of Illness IndexJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D D Duncan, O B Shukla, S K West, O D Schein. 1997. New objective classification system for nuclear opacification.. https://doi.org/10.1364/josaa.14.001197

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