Table 1 A summary of the metrics evaluated in this study.
Metric | Unit | Description |
|---|---|---|
Vessel area density (VAD) | % | Perfused blood vessel area in binarized OCTA MIP image divided by total image area |
Vessel length density (VLD) | % | Total length of all observable vessels measured along the vessel centreline divided by the total image area. Length measurements are calculated from the skeletonized OCTA MIP image |
Branchpoint density (BD) | Nodes/mm | Number of identified nodes divided by total vessel length |
Mean diameter (MeanD) | μm | Mean diameter derived from a local thickness algorithm applied to single vessels in the binarized OCTA MIP. Mean diameter is the mean for a single vessel including one value for each identified segment |
Median diameter (MedD) | μm | Median of single-vessel diameter measurements including one value for each identified segment |
Mean tortuosity (MeanT) | – | Tortuosity evaluated from the skeletonized image using the arc length-over-chord ratio |
Mean length (MeanL) | μm | Mean of the single-vessel centreline lengths including one value for each identified segment measured from the skeletonized image |
Median length (MedL) | μm | Median of the single-vessel centreline lengths including one value for each identified segment measured from the skeletonized image |
Fractal dimension (FD) | – | Indication of how the network fills space on variable length scales, calculated using the box counting method. FD is reported as FD ± FDerror27 |
