Observation of blood flow in verruca vulgaris using laser speckle contrast imaging before and after pulsed dye laser treatment / 中华皮肤科杂志

ABSTRACT

Objective To visualize blood flow changes in verruca vulgaris noninvasively with laser speckle contrast analysis (LSCA), and to evaluate the relationship of size and location of warts with efficacy of laser treatment. Methods Pulsed dye laser(PDL)was used to treat 30 verruca vulgaris lesions in 17 patients. In order to evaluate therapeutic effect of PDL, LSCA was performed to observe blood flow in warts and their surrounding normal skin, and to calculate speckle flow index (SFI)values before laser treatment, and at 10 minutes as well as on 3 weeks after laser treatment. Results Before PDL treatment, SFI values were significantly higher in warts than in their surrounding normal skin (11.600 ± 1.190 vs. 5.280 ± 0.481, t = 8.169, P < 0.01). Compared with those before the treatment, SFI values in warts significantly decreased at 10 minutes(3.112 ± 0.484, t = 4.407, P < 0.01)and on week 3(7.315 ± 1.083, t = 3.294, P < 0.01)after the treatment, and were significantly higher on week 3 than at 10 minutes (t = 4.646, P < 0.01). SFI values in surrounding normal skin significantly increased at 10 minutes after the treatment compared with those before the treatment (20.260 ± 2.063 vs. 5.296 ± 0.708, t = 6.770, P < 0.01), but were significantly lower on week 3 than at 10 minutes (4.941 ± 0.616, t = 6.964, P < 0.01). No significant difference was observed between SFI values in surrounding normal skin on week 3 after the treatment and those before the treatment (t = 0.378, P = 0.707). The efficacy of laser treatment was associated wart size and location. Changes of blood flow(|ΔSFI|)were significantly higher in warts measuring less than 0.5 cm2 in size than in those equal to or more than 0.5 cm2 (t = 2.287, P < 0.05), and significantly differed among warts at different sites (F =15.71, P < 0.01). The greatest changes of blood flow in warts were observed on fingers, followed by the dorsum of feet, toes, palms and soles and periungual areas. Conclusions Blood flow in verruca vulgaris is markedly increased compared with that in normal skin. PDL can clear verruca vulgaris by solidifying and gasifying capillaries. LSCA may be used to evaluate the efficacy of laser on verruca vulgaris more quantitively by monitoring regional blood flow.