The Acute Damage Effect Of Microneedle Combine With Photodynamic Therapy In The Treatment Of Port Wine Stains

Part 1 Study of microneedle effect on transdermal permeation of 5-aminolevulinic acidObjective: 5-aminolevulinic acid(ALA) transdermal permeation is the main factor to determine 5-aminolevulinic acid photodynamic(ALA-PDT) effect. To discuss whether microneedles application can increase ALA transdermal permeation rate, so that to enhance photodynamic effect, this experiment aims at to observe after microneedles combine with ALA act upon combs, the pharmacokinetics of protoporphyrin IX(Pp IX) generated from ALA in comb tissues. Methods: Using comb as Port Wine Stain animal model, divided the chickens into ALA group and microneedles combine with ALA group. ALA group apply 5-ALA only, microneedles combine with ALA group use microneedles barrelling chicken comb first then apply 5-ALA,both of them use untreated side as self-control. The localization of Pp IX was observed under inverted fluorescent contrast phase microscope, and the fluorescence intensity of Pp IX was calculated by fluorospectro photometer. Results: In the comb, Pp IX content increased gradually after applying ALA. It achieved the peak level at 4hours in two groups, and then obviously decayed after 6 hours,but the Pp IX level was higher in group B than group A,with significant difference(all P<0.05). Inverted fluorescent contrast phase microscope showed that Pp IX in two groups distributed evenly in vascular tissue of dermis and the fluorescent in group B was stronger than group A. Conclusions: Microneedles contribute to 5-ALA transdermal permeation, and can increase Pp IX level in local tissues.Part 2 The acute damage effect of microneedles combine with ALA-PDT in the treatment of PWSObjective: To explore the efficacy of microneedles combine with aminolevulinic acid-photodynamic therapy(ALA-PDT) in the treatment of Port Wine Stain(PWS) comb model, and to determine whether microneedles can help enhance the effect of ALA-PDT to treat PWS. Methods: Using comb as Port Wine Stain animal model. A total of 42 leghorns were selected randomly and equally divided into 7 groups: blank control group receiving no treatment, three ALA-PDT groups irradiated with 630-nm red laser at 75, 100 and 150 J/cm2 respectively, three microneedles combine with ALA-PDT groups irradiated with 630-nm red laser at 75, 100 and 150 J/cm2 respectively. Tissue specimens were obtained on the 1st, 3rd and 7th days after treatment followed by the observation of morphological and histological changes, then calculating capillary number decrement rate. Results: Except blank control group, All six experimental groups’ experimental regions showed shallow and pale in varying degrees, microscopic observation showed dermal capillary number and pipe diameter decreased. As energy density increased, response of all six experimental groups were enhanced, and microneedles combine with ALA-PDT groups showed aggravated damage degree than ALA-PDT groups. Conclusions: Contrast to ALA-PDT, Microneedles combine with ALA-PDT has a better damage effect on comb capillary.