Polyacrylamide Hydrogel Biological Characteristics Of The Experimental And Clinical Case Analysis

In 1997, polyacrylamide hydrogel was introduced into China and used in clinical practice as a kind of injectable soft tissue filler. We have observed many patients developed varieties of complications after polyacrylamide hydrogel injection. Which reason causes the complications, the characteristic of the material or the method of injection, has not been definite. Through literature review, the information provided by basic and clinical researches about the underlying mechanism, especially the local and systematic immune reactions, is not rich. It is very difficult to explain some postoperative symptoms by the current knowledge. To evaluate the advantages of materials, we studied the polyacrylamide hydrogel and the silicon gel implant by animal experiment and clinic analysis.1 Animal ExperimentNowadays, the most popular implants used in breast augmentation mammaplasty are silicon gel implant and polyacrylamide hydrogel. We put implants into the subcutaneous soft-tissue of New Zealand rabbits. In treatment group, we injected polyacrylamide hydrogel into subcutaneous tissue (5ml/kg); in control group, we implanted 10ml silicon gel implants at the same location. There was no difference between treatment and control groups in terms of formation of capsule right after implantation. However, in treatment group, gel diffused into surrounding tissues in the third and eighth month after implantation. Especially in muscular tissue, gel diffused along the muscular fibers and prevented the formation of capsule. The outcome of diffusing gels in muscular tissue is still unknown. In control group, the implants were tightly surrounded by capsules. Halmatoxylin and Eosin(HE) stained biopsy sample slices showed that, in both groups, the number of lymphocyte decreased along with time. In treatment group, the number of lymphocyte is seemed higher than the control group. However, there is no statistical significant difference between 2 groups along with time in terms of the number of lymphocyte (p>0.05).In the eighth month after implantation, we examined the nerve conduction velocity and the peak amplitude of action potential of sciatic nerve. We found that the conduction...