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| Videocapillaroscopic parameters | Criteria |
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| Distribution of the capillaries | |
| Regular | Homogenous distribution of capillaries |
| Altered | Nonhomogenous distribution of capillaries |
| Density of the capillaries | |
| Normal | 9–13 capillaries/mm |
| Increased | >13 capillaries/mm |
| Decreased | <9 capillaries/mm or avascular area |
| Diameter of the capillaries | |
| Normal | The diameter of the afferent limb (6 to 19 μm) and the diameter of the efferent limb (8–20 μm), venous limb width ratio: arterial limb no greater than 2 : 1 |
| Enlargement of the top part of the loop | Diameter of the limbs larger than average |
| Enlargement of the efferent limb | Diameter of the limbs larger than average |
| Length of the capillaries | |
| Normal | Approximately 400 μm |
| Elongated | >750 μm |
| Extravasation | |
| Absent | No extravasations |
| Single | Present in 1-2 fingers |
| Multiple | Present in >2 fingers |
| Subpapillary venular plexus visibility | |
| Invisible | |
| 1-2 fingers | Visible in 1-2 fingers |
| >2 fingers | Visible in >2 fingers |
| Background colour | |
| Pale | |
| Pink | |
| Reddish | |
| Morphology of the capillaries | |
| Normal | Appearance like an inverted letter U |
| Tortuous capillaries—regular appearance | Single crossovers |
| Tortuous capillaries—irregular appearance | Multiple crossovers or appearance like “treble clef” loop, “antler” loop, “trefoil” loop or meandering appearance with single/multiple crossovers |
| The number of tortuous capillaries | |
| Single | <5 at least in two fingers |
| Multiple | >5 at least in two fingers |
| Branching capillaries | |
| Present | At least one such loop in two fingers |
| Coiled capillaries | |
| Present | At least one such loop in two fingers |
| Features of the capillary neoformation | |
| Present | Thin, branching from one limb, or thin interconnection between the limbs (at least one such loop in two fingers) |
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