Objeetive To discuss a reasonable postoperative management of breast augmentation by polyacrylamide hydrogel (PAHG) injection.Methods The retrospective study was used to analyze 157 cases which received breast augmentation by PAHG injection.MRI was used in all of cases preoperatively.Among these patients,23 were located by three-dimensional (3D) reconstruction,the content of mono acrylamide in the serum of 71 cases were examined in the hydrogel of 23 cases and in the tissue around the hydrogel of 12 cases,respectively.The silicone gel implants were planted after the removal of PAHG in 7 cases.Results MRI-3D could show the injectants location,scope,layer and integrality more intuitional and more detailed.The momo acrylamide was found in the serum with 7 cases,in the hydrogel with 5 cases,in the tissue around the hydrogel with 3 cases.131 cases gained satisfactory results.All the cases received 3 to 6 months follow-up.The scleroma was not found after the palpation of breast.In the 7 cases that were planted with the silicone gel implants immediately,the shape and texture of the breast were both great.Conclusions The preoperative MRI examination is a first-choice,and if possible,3D reconstruction is better.With the detecting methods so far,there is no strong evidence to support the possibility of PAHG resolving into poisonous acrylamide inside the human body.During the operation,the injectant,the integument around the hydrogel and degenerative tissue should be orthoptically cleared-up as much as possible.Sucking the injectant blindly is not commended.The silicon gel prosthesis is planted to reconstruct the shape of breast immediately,but the prerequisite is that the patients have this demand and that the muscle is intact without inflammation.