Research On Hyperplastic Scar By Radiotherapy

Objective This study adopts plenty projects which are commonly used in the clinical radiotherapy at present. By the 6Mev high energy electrons'Lines which are generated by medical linear accelerator, irradiating the scar model on rabbit ears, and observing the pathological variety to the wound healing, detecting the variation of ACTIN and VEGF in irradiated organization with immunohistochemical method. The project of the radiation treatment to hypertrophic scars will be further improved via this study, and it makes positive influences to guide the reasonable, safe, and effective scar treatment in clinical.Methods Use 18 New Zealand white rabbits (36 ears), make a round wound of 6mm diameter which should be in cartilage layers in each rabbit's ear, in all 360 scars are randomly divided into six groups, one of them is the irradiation control group (3 rabbits), the other five groups are irradiation groups (3 rabbits). Irradiate the wound on rabbit's ears with 6Mev electron beam produced by the linear accelerator; the radiation area is protected by Lead. Division status: the first group is 200cGy (2000cGy/10 times/10 days, a does is 200cGy, once per day, radiate 10 times continuously), the second one is 400cGy (2000cGy / 5 times / 5 days, a dose is 400cGy, once every other day, radiate 5 times continuously), the third one is 600cGy (1800cGy / 3 times / 3 days, a dose is 600cGy, every other three days time, radiate 3 times continuously), the fourth one is 800cGy (1600cGy / 2 times / 2 days, a dose is 800cGy,every other once a week, radiate 2 times continuously), the fifth group is 1000cGy (2000cGy / 2 times / 2 days, a dose is 1000cGy, once every other week, radiate 3 times continuously) for three rabbits. Observe the wound healing process and period, and the progress of partial hyperplasia on the healed wound. After one month, adopt the irradiation control group and the irradiation group for light and electron microscopy.Results The healing of wound in each irradiation group is delayed; Under the circumstance that almost all dose of radiation are the same, it will make a noticeable influence difference to the formation of hypertrophic scar with the different single doses of radiation on it, there is a dose-effect relationship between 200cGy and 1000cGy.Conclusion The ventral ears of New Zealand white rabbits can generate the similar hypertrophic scar tissue variation with human being under the circumstance without any stimulant, which could be taken regard as animal models to study pathological scars. The animal experiments prove that it has the remarkable therapeutic effect to irradiate the proliferation scars with 6Mev electron beam; there is a dose– effect relationship between them. The single dose is 400cGy, irradiate 5 times, the treatment result of scar will be best.