Steps of calculation of the automatic full field perfusion image analyser (Source: matrix of intensity–time curves (64×256), gained by scanning laser doppler flowmetry (HRF))
| (1) | Fast Fourier analysis of all intensity–time curves |
|---|---|
| (2) | Calculation of the offset, flow, volume, and velocity |
| (3) | Interactive marking of |
| Saccades | |
| Rim area | |
| (4) | Automatic exclusion of |
| Pixels with incorrect DC values (underexposed, overexposed pixels) | |
| Pixels of excavation area | |
| Pixels of artificial movements (saccades) | |
| (5) | Automatic characterisation of the retinal vessel tree by a vessel detection algorithm based on the intensity image and the perfusion image |
| (6) | Automatic exclusion of vessels with a diameter greater than 30 μm |
| (7) | Moving average of the perfusion map with 5×5 pixel size |
| (8) | Automatic calculation and statistical analysis of total flow in the temporal, nasal, and rim area |
| Mean flow | |
| Standard deviation | |
| Box plot | |
| Histogram | |
| Cumulative distribution curve | |
| Capillary pulsation index |