Dermoscopic features of port-wine stains: A study of 264 cases.

Background: Port-wine stains (PWS) occur in 0.3-0.5% of the population. However, the dermoscopic features of PWS have not been systematically studied.

Methods: Dermoscopic images of 264 cases with PWS were retrospectively analysed.

Results: Linear vessels were the most frequent dermoscopic features of PWS (42.0%). Other dermoscopic features were reticular vessels (28.0%), sausage-like vessels (13.6%), dots or globules vessels (9.1%) and mixed vessels (7.2%). Nonvascular morphology comprised white circles (13.6%) and whitish veil (38.3%). Sausage-like vessels and whitish veil were mainly present in the thickened type and in those with PWS aged ≥18 years; mixed vessels were mainly present in purple type of PWS. Dermoscopic features showed no significant difference between lesions located on different facial areas (V1, V2 and V3). Dots or globular vessels were more common in non-facial lesions (P < 0.0001). White circles were only found in the facial lesions, and the frequency of white circles and whitish veil was higher in the treated group than in the untreated group (P = 0.004 and P = 0.04, respectively). The frequency of white circles was significantly higher in the prior treated group than in the untreated group (P < 0.0001).

Conclusion: There are various of dermoscopic features of PWS. The dermoscopic features of patients with PWS may correlate with age, subtype, location, prior treatment history and pulsed dye laser (PDL) resistance.