[Preventive effect of chitosan on capsular contracture after implantation of silicone gel-filled mammary implants in rats].

OBJECTIVE:To study the preventive effect of chitosan on capsular contracture after implantation of silicone gel-filled mammary implants in rats. METHODS:18 SD female rats were divided into three groups randomly. Small silicone gel-filled mammary implants were implanted under each side of latissimus dorsi muscle. Chitosan was injected into left cavities as experimental sides, and nothing was injected into right cavities as control sides. 4, 8 and 12 weeks postoperation, specimens were dissected and observed using light microscope, and area density of collagen both type I and type III were also detected. RESULTS:Fibrous capsules around implants consist of two layers: dense layer and loose layer. 4 weeks postoperation, total thickness of the experimental sides was less than that of the control sides (P < 0.01). Area density of collagen either type I or type III of the experimental sides was lower than that of the control sides (P < 0.01). Both 8 and 12 weeks postoperation, total thickness of the experimental sides was less than that of the control sides (P < 0.05). Area density of collagen type I of the experimental sides was lower than that of the control sides (P < 0.05). Area density of collagen type III was of no statistical difference between the experimental sides and the control sides (P > 0.05). CONCLUSIONS:Chitosan can remarkably prevent capsule contracture during the early period after implantation of silicone gel-filled mammary implants.