Supplemental Table 1 – Perfusion Examination of the Plantar Muscular Compartment in Patients without Vascular Compromise

Examined Plantar Compartment / Mean Perfusion (5 trials) in mL/g/s / Std Dev (5 trials) / Co- Vari-ation / Perfusion t-Values Comparison Between Feet of Same Patient / Intra-Subject Perfusion ratios / Maximum Slope of Tissue Enhancement vs. Time Series / Intra-Subject Slope ratios
Subject 1 Rt / 6.48E-04 / 2.54E-05 / 0.039 / 26.41 / 2.11 / 6.92E-02 / 1.96
Subject 1 Lt / 3.07E-04 / 1.39E-05 / 0.045 / 3.53E-02
Subject 2 Rt / 4.23E-04 / 2.80E-05 / 0.066 / 4.48 / 0.85 / 4.41E-02 / 0.82
Subject 2 Lt / 4.97E-04 / 2.35E-05 / 0.047 / 5.40E-02
Subject 3 Rt / 11.2E-04 / 4.77E-05 / 0.043 / 2.34 / 1.08 / 14.6E-02 / 1.13
Subject 3 Lt / 10.4E-04 / 4.94E-05 / 0.048 / 13.0E-02
Subject 4 Rt / 9.71E-04 / 6.69E-05 / 0.069 / 1.3 / 0.95 / 9.68E-02 / 0.99
Subject 4 Lt / 10.2E-04 / 4.56E-05 / 0.045 / 9.74E-02
Subject 5 Rt / 15.7E-04 / 15.1E-05 / 0.096 / 1.94 / 1.12 / 15.1E-02 / 1.35
Subject 5 Lt / 14.0E-04 / 12.5E-05 / 0.089 / 11.2E-02
Subject 6 Rt / 9.37E-04 / 8.64E-05 / 0.092 / 0.18 / 1.01 / 8.73E-02 / 0.99
Subject 6 Lt / 9.26E-04 / 10.4E-05 / 0.112 / 8.83E-02
Subject 7 Rt / 19.5E-04 / 12.2E-05 / 0.063 / 3.06 / 1.15 / 22.9E-02 / 0.90
Subject 7 Lt / 17.0E-04 / 12.6E-05 / 0.074 / 25.3E-02
Subject 8 Rt / 8.45E-04 / 5.23E-05 / 0.062 / 1.57 / 1.08 / 8.84E-02 / 1.19
Subject 8 Lt / 7.84E-04 / 6.96E-05 / 0.089 / 7.44E-02
Subject 9 Rt / 8.60E-04 / 4.24E-05 / 0.049 / 1.58 / 0.95 / 11.1E-02 / 1.06
Subject 9 Lt / 9.05E-04 / 4.76E-05 / 0.053 / 10.5E-02
Subject 10 Rt / 18.1E-04 / 12.2E-05 / 0.067 / 9.59 / 1.52 / 24.6E-02 / 1.43
Subject 10 Lt / 11.9E-04 / 7.95E-05 / 0.067 / 17.2E-02
Subject 11 Rt / 6.60E-04 / 6.22E-05 / 0.094 / 1.88 / 0.91 / 9.93E-02 / 0.80
Subject 11 Lt / 7.24E-04 / 4.42E-05 / 0.061 / 12.4E-02
Subject 12 Rt / 3.02E-04 / 1.57E-05 / 0.052 / 2.11 / 0.92 / 4.03E-02 / 0.95
Subject 12 Lt / 3.27E-04 / 2.20E-05 / 0.067 / 4.27E-02
Subject 13 Rt / 7.39E-04 / 4.50E-05 / 0.061 / 1.43 / 0.95 / 8.61E-02 / 1.03
Subject 13 Lt / 7.74E-04 / 3.08E-05 / 0.04 / 8.38E-02
Subject 14 Rt / 16.9E-04 / 29.5E-05 / 0.175 / 1.67 / 1.17 / 16.8E-02 / 1.40
Subject 14 Lt / 14.5E-04 / 11.5E-05 / 0.079 / 12.0E-02
Mean / 9.85E-04 / Mean / 1.13 / 1.13E-01 / 1.14
Std Dev / 4.64E-04 / Std Dev / 0.33 / 0.0585 / 0.31
Co Variation / 0.47 / Co Variation / 0.29 / 0.52 / 0.27

Abbreviations: Left Foot (Lt), Right Foot (Rt), Standard Deviation (Std Dev), Coefficient of Variation (Co Variation)

Caption: In healthy subjects, the standard deviation of perfusion measurements is typically an order of magnitude less than the perfusion estimate itself, thus indicating low intra-observer variability in perfusion estimates. Based upon a paired T test, several Subjects (4/14) have significantly different perfusion values between feet. Normal subjects also demonstrated a wide range of perfusion values, with the standard deviation of perfusion values across all feet equaling approximately half the perfusion estimate itself (coefficient of variation is 0.47). The data are better behaved if we consider the perfusion values as a ratio between the two feet (i.e. the foot with greater perfusion being in the numerator). The perfusion values between patients then demonstrate a tighter distribution (mean 1.13 and standard deviation 0.33).

Supplemental Table 2 – Tissue Perfusions vs. the Maximum Rate of Tissue Enhancement of the whole foot in Patients without Vascular Compromise

Subject / Perfusion Index / Intra-Subject Perfusion ratio / Maximum Slope of Tissue Enhancement vs. Time Series / Intra-Subject Slope ratios
1 Rt / 26.5E-05 / 0.68 / 21.5E-03 / 0.89
1 Lt / 39.1E-05 / 24.1E-03
2 Rt / 14.6E-05 / 1.38 / 12.2E-03 / 1.57
2 Lt / 10.6E-05 / 7.77E-03
3 Rt / 28.7E-05 / 1.49 / 29.7E-03 / 1.36
3 Lt / 19.2E-05 / 21.7E-03
4 Rt / 41.6E-05 / 2.25 / 14.1E-03 / 1.49
4 Lt / 18.5E-05 / 9.43E-03
5 Rt / 25.7E-05 / 0.94 / 18.4E-03 / 1.31
5 Lt / 27.3E-05 / 14.0E-03
6 Rt / 20.6E-05 / 1.37 / 12.4E-03 / 1.18
6 Lt / 15.1E-05 / 10.5E-03
7 Rt / 22.2E-05 / 0.85 / 18.2E-03 / 0.73
7 Lt / 26.1E-05 / 24.8E-03
8 Rt / 8.53E-05 / 1.15 / 8.6E-03 / 1.63
8 Lt / 9.80E-05 / 14.1.E-03
9 Rt / 25.1E-05 / 0.62 / 19.2E-03 / 0.88
9 Lt / 40.5E-05 / 21.8E-03
10 Rt / 58.3E-05 / 1.34 / 58.5E-03 / 1.40
10 Lt / 43.5E-05 / 41.9E-03
11 Rt / 11.4E-05 / 0.99 / 8.62E-03 / 0.76
11 Lt / 11.5E-05 / 11.3E-03
12 Rt / 3.18E-05 / 0.94 / 3.25E-03 / 0.86
12 Lt / 3.37E-05 / 3.80E-03
13 Rt / 11.4E-05 / 1.00 / 9.44E-03 / 1.08
13 Lt / 11.3E-05 / 8.73E-03
14 Rt / 25.7E-05 / 0.96 / 15.2E-03 / 1.05
14 Lt / 26.7E-05 / 14.5E-03
mean / 22.4E-05 / 1.14 / 17.2E-03 / 1.16
std dev / 13.2E-05 / 0.41 / 11.8E-03 / 0.30
Coefficient Variance / 0.59 / 0.36 / 0.69 / 0.26

Abbreviations: Right Foot (Rt), Left Foot (Lt), Standard Deviation (Std Dev)

Caption: We now consider soft tissues of the entire foot as a single structure where perfusion is measured en bloc. We find that the coefficient of variation for both perfusion estimates and the ratio of perfusion estimates (where ratio is expressed as the higher/lower perfusion value in individual patients) is higher using the entire foot approach than using only the plantar compartment as in table 2 (0.59 vs 0.47 for perfusion estimates, 0.36 vs 0.29 for ratios) and likely owing to the relatively greater heterogeneity of the tissues under examination. Considering tissue enhancement slope alone, the distribution is similarly varied using raw values (coefficient of variation 0.69 vs. 0.59) but remains resonably compact when ratios are considered (0.35 vs. 0.32).