Fluorescence lifetime imaging ophthalmoscopy (FLIO) in the healthy eye.

A) Fundus autofluorescence intensity (FAF) and fluorescence lifetime (FLIO) images in the short (498–560 nm) and the long (560–720 nm) spectral channel. A standard ETDRS grid was used for quantitative analysis of individual grid areas (C = Center (diameter d = 1mm), IR = inner ring (d = 3mm), OR = outer ring (d = 6mm)). B) Corresponding scatter plots with overlaid decay histogram illustrate the decay times of individual locations such as the macular center (red square), and the optic nerve head (blue square). X-axis: Time line, y-axis: Number of detected photons (logarithmic scale). Below the decay curve, the corresponding residuals are displayed, indicating how precise the raw data is approximated by the fitting curve. Blue dots: Number of photons at this specific point in time at this location (binning fact(1)or = 1); red curve: Fitting line; green line: Instrument response function.