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Date of download: 6/18/2016 Copyright © 2016 American Medical Association. All rights reserved. From: Quantification of Fundus Autofluorescence to Detect Disease Severity in Nonexudative Age-Related Macular Degeneration JAMA Ophthalmol. 2013;131(8):1009-1015. doi:10.1001/jamaophthalmol.2013.4014 Fundus Autofluorescence Signature GenerationA, The signature is derived from a 400 (horizontal) × 50 (vertical)-pixel box centered on the fovea. B, All pixel values from this box are plotted. gsi Indicates gray-scale intensity. C, Pixels at the same horizontal location are averaged to yield a characteristic fundus autofluorescence signature. Figure Legend:
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Date of download: 6/18/2016 Copyright © 2016 American Medical Association. All rights reserved. From: Quantification of Fundus Autofluorescence to Detect Disease Severity in Nonexudative Age-Related Macular Degeneration JAMA Ophthalmol. 2013;131(8):1009-1015. doi:10.1001/jamaophthalmol.2013.4014 Comparing Fundus Autofluorescence (FAF) Signatures to Calculate the Index of Retinal AutofluorescenceAn age-related macular degeneration (AMD) FAF signature (taken from image A) is plotted against the averaged control FAF signature (B). Using a difference of squares method, the Index of Retinal Autofluorescence quantifies both hyperfluorescent (arrow) and hypofluorescent (arrowhead) changes caused by AMD. gsi Indicates gray-scale intensity. Figure Legend:
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Date of download: 6/18/2016 Copyright © 2016 American Medical Association. All rights reserved. From: Quantification of Fundus Autofluorescence to Detect Disease Severity in Nonexudative Age-Related Macular Degeneration JAMA Ophthalmol. 2013;131(8):1009-1015. doi:10.1001/jamaophthalmol.2013.4014 Effect of Defocusing and Gain Setting on Index of Retinal Autofluorescence (IRA)Focusing adequate to obtain retinal vessels measuring 15 to 25 μm (A-C) and gain settings with total sensitivities ranging from 67 (F) to 100 (G) did not significantly affect IRA reproducibility. Defocusing (D) and excessive gain (E and H) adversely affected IRA reproducibility. Figure Legend:
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Date of download: 6/18/2016 Copyright © 2016 American Medical Association. All rights reserved. From: Quantification of Fundus Autofluorescence to Detect Disease Severity in Nonexudative Age-Related Macular Degeneration JAMA Ophthalmol. 2013;131(8):1009-1015. doi:10.1001/jamaophthalmol.2013.4014 Comparison of Index of Retinal Autofluorescence (IRA) Signatures of the Same Eye During Disease ProgressionA, Subject with minimal clinical progression shows no appreciable increase in IRA with serial testing. gsi 2 Indicates gray-scale intensity squared. B, Subject with slow clinical progression exhibits modestly increased IRA during sequential testing. C, Subject with rapidly progressive age-related macular degeneration shows large increases in IRA. Figure Legend:
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Date of download: 6/18/2016 Copyright © 2016 American Medical Association. All rights reserved. From: Quantification of Fundus Autofluorescence to Detect Disease Severity in Nonexudative Age-Related Macular Degeneration JAMA Ophthalmol. 2013;131(8):1009-1015. doi:10.1001/jamaophthalmol.2013.4014 Ordering of Age-Related Macular Degeneration Fundus Autofluorescence Images by Retina Specialists and Individual Index of Retinal Autofluorescence (IRA) ValuesLower numbers represent more advanced age-related macular degeneration. A, Subjective ordering by retinal specialists is strongly correlated (r s = 0.93, Spearman rank coefficient). B, A similarly strong correlation is found between subjective ordering of fundus autofluorescence images and ordering using their respective IRA values (r s = 0.77, Spearman rank coefficient). Figure Legend:
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Date of download: 6/18/2016 Copyright © 2016 American Medical Association. All rights reserved. From: Quantification of Fundus Autofluorescence to Detect Disease Severity in Nonexudative Age-Related Macular Degeneration JAMA Ophthalmol. 2013;131(8):1009-1015. doi:10.1001/jamaophthalmol.2013.4014 Box Plot of Index of Retinal Autofluorescence (IRA) Values Compared With Age-Related Eye Disease Study (AREDS) GradingThe IRA values are positively correlated with AREDS grades (r s = 0.73, Spearman rank coefficient). All AREDS grades are individually significantly different than controls (pairwise comparisons, all P <.01). The largest increase in median IRA occurs between AREDS grades 3 and 4 (P <.001). Figure Legend:
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