To evaluate the safety, reliability and effectiveness of "free style endoscopic technique" assisted transaxillary high level dual plane breast augmentation; To explore endoscopic techniques that can achieve higher efficiency and better result ; To discover a safe and effective method for dual plane dissection with the help of endoscopy.

Using new endoscopic techniques to perform transaxillary dual plane breast augmentation: ① High level dual plane technique, the muscle division line is about 1.5 cm higher than the original inferior mammary fold, the cephalic side of the muscle is retracted to the lower border of the areola with a special retractor to form a high level dual plane cavity, thus the upper and lower portion of the implant would be covered by pectorilis major muscle, while the rest of the implant was partially under breast parenchyma. ② "Free style endoscopic techniques" , the endoscopy and retractor are not fixed to each other, thus the space is exposed by an assistant with a new designed special retractor, while the operator is concentrate on dissecting with endoscopy in one hand and long tipped bowie in the other hand. ③ Accurate navigate technique, define the dissection border by acupuncture via skin in a 90 degree angle, thus to make the dissection right as preoperative design.

There were 1 106 cases underwent this kind of surgery, while 405 of them, whose minimum follow up were 12 months were included in this retrospective study. The follow up period ranged from 12-60 months, the average follow up period is 24.3 months. The average operation time is (1.47 ±0.46) h, the average drainage removal time is (4.23±0.51) d after surgery. The perioperative complication rate is 0.99%, including an incision site change caused by intraoperative bleeding, 1 case of pneumothorax, 2 cases of bleeding after surgery. Long period complication including: 6 cases (1.48%) Ⅲ grade capsular contracture, 21 cases (5.20%) of nipple-areola sensation disorders, implant palpable occurred in 14 case (3.46%), 3 cases (0.74%) implant malposition, 2 cases (0.49%) implant distortion, the total reoperation rate is 2.47%. There was no infection, hematoma, seroma, curtain deformity, double bubble deformity occurred in our study.

The high level dual plane techniques not only can solve the deficient soft tissue coverage problem thus to lower the rate of implant palpability, but also can relieve the relationship of the pectorilis major muscle and the inframammary fold(IMF), offering an option to replace Ⅱ and Ⅲ type of dual plane techniques, decrease the risk of curtain deformity and double bubble deformity. The free style endoscopic techniques are very flexible and efficient, with the help of accurate navigate technique, it can archive an accurate cavity dissection, accurate and definite IMF, and a lower complication rate. Though the learning curve is relatively longer, it is really a safe and effective breast augmentation method worthwhile to learn and spread.

Breast augmentation; Endoscopes; Dual plane; Breast implant