This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG) angiography using in vitro experiments and prospective observational study.
The fluorescence intensity had an inverse correlation with distance, and the transitional zone was shown at the distance of 4-5 cm by slope differential. FMAX , T1/2MAX , and Slope were affected significantly by camera distance, site of angiography, fluorescence emission source, ICG modes as conditional factors. On multivariate analysis, FMAX was independently associated with spectral ICG mode with red inversion, Laser mode, and camera distance. Conversely, TR was not related to any conditional factors.
Since quantitative parameters of ICG angiography are influenced by various conditions, a standardized protocol is required. The application of ICG specific modes with a constant distance of 4-5 cm can provide optimized fluorescence images.