Objective:To explore the histopathological change of the fragrant pig skin induced by focus ultrasound repetition irradiation to offer experiment basis for the safety and effectivessness of clinically treating postherpetic neuralgia(PHN) by repetition irradiation.Methods:The pig skin was irradiated once every other day

altogether three

with irradiation power as 2W

and frequency as 10.06MHz

The skin change was observed under light microscope and electron microscope.Results:Hyperemia and edema in irradiation area after irradiation were observed instantly to the eye;Under light microscope there were hyperemia and edema in epidermis

angiotelectasis and inflammatory infiltrating

and find coagulative necrosis in slice was not observed.Under electron microscope

instantly after ultrasound irradiation every other day

endothelial cell of blood vessel can be found mitochondria swelling and more micropinocytotic vesicles

mitochondria swelling and rough endoplasmic reticulum dilatation were noted for in fibroblasts

and mitochondfia swelling for nerve fibre.Conclusions:(1)There is reversibile lesion in epidermis under this dose of ultrasound.(2)Skins don’t accumulate lesion every other day after irradiation repeatly .which illustrates that it is effective and safe to treat postherpetic neuralgia by ultrasound irradiation repeatly.