Figure 1 Representative photomicrographs of foot-pad B16 melanoma, 7 (left) and 14 (Right) days after injection.
Figure 1 Representative photomicrographs of foot-pad B16 melanoma, 7 (left) and 14 (Right) days after injection.
Figure 2 Photography of the surgical vascular tourniquet system. Right leg occlusion photography issued from preliminary experiments. Only left side was used for definitive experiment. Surgical needle holder permitted to tighten the tourniquet around the leg basis. Thick red arrow reveals the vascular tourniquet silicone external part, which is tighten by a surgical needle holder (thick black arrow), clamped on tissue lac (thin red arrow). Thus, leg perfusion was totally occluded at the leg basis. Thin black arrow represents the isoflurane nose.
Figure 3 Laser speckle contrast images of healthy skin (A) and melanoma (B) after 14 days. Dotted line represents the corresponding ROI. Tumor ROI were generally very well perfused in the periphery, and sometimes displayed central hypoperfusion zones (Thin black arrows). Black thick arrow reveals the foot-pad vessels. Foot-pad vessels disappeared at 14 days, i.e. at the time of the laser speckle contrast imaging measurement.
Figure 4 Evolution of median healthy skin and melanoma perfusion over 20 min of laser speckle contrast imaging measurement. *p< 0.05, vertical bar indicates interquartile. Black line represents melanoma perfusion, grey line healthy skin perfusion.
Figure 5 Boxplot graphic of healthy skin and melanoma hyperemia percentage secondary to 30 seconds and 3 minutes of vascular occlusion. All groups have mutually statistical significant difference compared to 3 minutes occlusion in healthy skin group (p<0.05).
Figure 6 One B16 Melanoma perfusion curve (blue) issued from laser speckle contrast imaging software, compared to healthy skin perfusion (red). Tumor hyperemia peak is showed by a black arrow. Melanoma basal perfusion is higher than healthy skin, but hyperemia percentage is weaker, secondary to 3 minutes of vascular occlusion.
Figure 7 Negative correlation curve between melanoma hyperemia percentage and melanoma volume. Smallest melanoma had the highest hyperemia percentage (superior to 100%), compared to the biggest melanoma that showed a hyperemia percentage inferior to 20%.
| Basal perfusion | 5 min | 10 min | 15 min | 20 min | |
| Melanoma | 108.36 (17.25) | 89.18 (22.48)* | 79.11 (27.44)* | 81.09 (35.38)* | 88.73 (28.3)* |
| Healthy Skin | 36,85 (4.98) | 32,25 (4.38)* | 33,45 (7.1) | 29,65 (12.83) | 31,95 (15.93) |
Table1 Quantitative analysis of Laser speckle contrast imaging perfusion of healthy skin and melanoma over 20 minutes of continuous measurement. *p<0.05 versus basal perfusion. Values are expressed as median values (interquartile).
| Healthy Skin | Melanoma | ||
| 30 secondes occlusion | 3 minutes occlusion | 3 minutes occlusion | |
| ROI surface (mm2) | 10 (2.2) | 9.4 (1.1) | 29.9 (5.7)* |
| Basal perfusion (PU) | 35.1 (4.6) | 32 (5) | 81.5 (33.3)* |
| Peak hyperemia (PU) | 74.5 (6.1) | 78.8 (24.3) | 131.7 (71.4)* |
| Hyperemia percentage (%) | 105 (24)* | 160 (42.4) | 48 (43.3)* |
| Time to peak (secondes) | 16.5 (3.3)* | 24.5 (8.3) | 46.5 (26.8)* |
| Hyperemia duration (secondes) | 46.5 (14.8)* | 146 (41) | 248.5 (67.5)* |
| Repayment/debt ratio (%) | 229.6 (76.9)* | 125.7 (37.3) | 143 (47.5)* |
Table2 Quantitative analysis of laser speckle contrast imaging perfusion of healthy skin and B16 melanoma post-occlusive reactive hyperemia (*p< 0.05 versus 3 minutes occlusion in healthy skin). Values are expressed as median values (interquartile).