OBJECTIVE: To investigate the aesthetic shaping method of breast reconstruction using the inferior rectus abdominis muscle flap (TRAM) to further improve the morphology of the reconstructed breast. METHODS: Firstly, we analyzed the breast and abdomen morphology of normal women, and combined with the specific operation of TRAM breast reconstruction, we elaborated the reconstruction shaping method from the aesthetic point of view. RESULTS: In normal women, there is a depression in the middle of the upper abdomen, a clear outline of the rectus abdominis muscle, and a bulging lower abdomen. The main determinants of breast shape are the inframammary fold, the lateral curvature, and the degree of sagging and fullness. The breast reconstruction process should follow the principle of symmetry, filling the subclavian and axillary tissue defects to simulate the morphology of a young abdomen and breast. Conclusion: The application of TRAM flap breast reconstruction process can improve the morphology of the reconstructed breast by improving the shaping method from the aesthetic point of view. Fazhi Qi, Department of Plastic Surgery, Zhongshan Hospital, Fudan University The breast is the symbolic organ of female secondary sexual characteristics, with dual functions of lactation and breastfeeding and cosmetology. Removal of a woman’s breast seriously destroys the perfection of a woman’s form and has a serious impact on the patient’s body and mind, even affecting the surrounding relationships and the stability of the family [1]. With the progress of breast cancer treatment, surgical excision of breast as well as chest tissues is on a shrinking trend, and local mass removal and breast-conserving treatment have been gradually promoted in Europe and the United States and other countries. However, breast-conserving treatment has not been universally accepted in Southeast Asian countries such as China and Japan due to the unique caution of Eastern peoples and the fear that tumors cannot be completely removed [2], and many patients still undergo modified radical surgery or radical surgery for breast cancer. Recently, with the improvement of living standard and the change of concept, more and more patients request breast reconstruction to improve the quality of life (QOL). The two main types of surgical approaches for breast reconstruction are breast implants and autologous tissue transplantation [1-7]. Since 1992, when the US Food and Drug Administration (FDA) restricted the use of silicone gel breast implants, the use of autologous tissue grafts for breast reconstruction has become mainstream, including the rectus inferior muscle flap (TRAM), the latissimus dorsi muscle flap, the gluteus maximus muscle flap, and the local thoracoabdominal flap, among which TRAM is the most widely used and is known as the “standard procedure” for breast reconstruction [2]. ” [2]. However, further research is needed to improve the sensation and shape of the reconstructed breast, both in terms of restoration and aesthetic shaping. In 1995, we started to apply TRAM flap for stage II breast reconstruction, and in 1998, we started immediate breast reconstruction based on stage II reconstruction, and have completed more than 40 cases with good treatment results. Today, we will analyze the aesthetic factors in breast reconstruction with our specific surgical methods. 1, the normal female breast and abdomen morphology analysis female breast with the growth of age and change, since the beginning of the teenage period, the first manifestation of the nipple areola bulge, to puberty, the breast slight bulge, chassis expansion, widening of the anterior axillary fold, breast body further expansion, the arc of the areola gradually shallow, and finally with the curvature of the breast body, breast further development and expansion into a hemisphere, reflecting the female morphological beauty. Then, after years and years, the breasts gradually shrink after the mission of breastfeeding is completed. The beauty of the mature female breast is reflected in both texture and volume. The breast is located between the 2nd and 6th ribs, between the sternal margin and the anterior axillary line, and extends outward to form the caudal lobe of the breast. The main features of breast reconstruction are the intermammary sulcus, the inframammary fold, the lateral curvature of the breast, the height of the nipple to the pectoralis major muscle and the degree of breast ptosis (Figure 1), and the shape of the anterior axillary fold. Breast reconstruction should follow the principle of symmetry on both sides, and only in cases of severe sagging and atrophy of the healthy side of the breast is it necessary to operate on the healthy side. In the abdomen of young women, there is a shallow groove between the rectus abdominis muscles on both sides in the middle of the supraumbilical abdomen, a deep umbilical depression, a slight subumbilical abdominal bulge, and a shallow oblique depression in the ribbed abdomen on both sides, further highlighting the morphology of the rectus abdominis muscles on both sides (Figure 1). The application of TRAM breast reconstruction has the dual effect of breast shaping and abdominoplasty, and should aim to produce symmetrical breasts with some expansion and sagging on both sides and beautiful curves, as well as the abdominoplasty, which shows the abdominal shape of young women with a depression in the middle of the upper abdomen, a clear shape of the rectus abdominis muscle and a slight expansion of the lower abdomen. 2, surgery operation surgery under general anesthesia, preoperative catheter insertion. First, the chest scar is excised, and the anterior chest flap is separated up to the subclavian bone, outside to the mid-axillary line, inside to the parasternal bone, down to the inframammary fold, and a subcutaneous tunnel is made in the middle of the chest toward the abdomen. When making the subcutaneous tunnel, excessive separation of the inframammary fold on the affected side and disruption of the intermammary sulcus pattern should be prevented. The periumbilical area is incised and the umbilicus is separated from the flap. The upper edge of the TRAM flap is then incised, and the fat layer is incised with an oblique entry toward the head to facilitate the flap to bring in more fatty tissue and major periumbilical penetrating vessels. The apron-like flap is separated cephalad on the surface of the rectus abdominis sheath, crossing over the edge of the rib arch and tunneling subcutaneously toward the thoracic trabeculae. When separating the abdominal flap, the surface of the rectus abdominis sheath is left partially adipose to facilitate lymphatic drainage. The lower edge of the TRAM flap is incised, and the fascial surface is peeled from the lateral side opposite the tip to the middle of the abdomen, and then peeled from the external to the internal side ipsilateral to the tip until the lateral skin penetration of the rectus abdominis muscle is revealed. The lateral border of the rectus abdominis muscle is cut off to reveal the intercostal artery. The sheath of the rectus abdominis muscle is incised at the junction of the middle and lower 1/3 of the flap, lateral to the skin penetration, and the rectus abdominis muscle is separated to locate the inferior abdominal wall arteries and to confirm the course of the vessels, minimizing the amount of muscle brought into the flap. In preparation for vascular anastomosis if necessary, the subabdominal wall vessels are separated to the femoral artery and taken as long as possible for backup. Since most abdominal wall hernias occur in the lower abdomen, as much of the rectus abdominis muscle and its sheath should be preserved in this area as possible in order to prevent postoperative abdominal wall hernia formation. In other words, the central rectus abdominis muscle and its sheath are cut about 3 cm wide in the inferior part of the umbilicus, and part of the muscles on the inner and outer sides are preserved. The supraumbilical portion gives priority to ensuring the blood supply of the flap, preserving only the lateral 1/3 of the rectus abdominis muscle, and bringing the medial muscle into the rectus abdominis muscle tip. The muscle is separated upward to the edge of the costal arch, and the superior abdominal wall artery that enters the muscle from under the costal cartilage is identified, and the flap is rotated and grafted to the chest and temporarily fixed. Closure of the anterior rectus abdominis sheath was performed top-down with a double 8-way suture with a No. 2 silk suture. The contralateral anterior rectus abdominis sheath is similarly partially sutured to maintain symmetry of abdominal wall tension, and the umbilicus is secured to the anterior rectus abdominis sheath so that the umbilicus is in a median position. The patient is adjusted in a semi-sitting position, and a hole is made in the middle of the skin and the fatty tissue around the inner skin cavity is cut away so that the newly formed navel has a deep depression. A longitudinal incision is made in the mid-abdominal fat layer above the umbilicus, the flap is reversed, and some of the fatty tissue at the edge of the longitudinal incision is cut away to form a subcutaneous depression. The flap was repositioned and fixed with several stitches in the median abdominal depression and the anterior sheath on both sides of the abdomen to simulate the shape of a young female abdomen. A drainage tube is placed and the suprapubic incision is adjusted from the outside to the inside with sutures to avoid the formation of cat ears on both sides, and finally the periumbilical area is sutured. There are two types of flap placement, longitudinal and transverse, and most of the single-tipped TRAM flaps are in an external superior oblique longitudinal configuration. The upper lateral 1/4 of the flap, the quadrant of the flap, is first excised. The upper end of the flap is sutured and secured to the upper edge of the anterior chest cavity, simulating the caudal lobe and anterior axillary fold of the breast, then the medial, inferior, and lateral sides of the breast are secured, excess skin is excised, folded and shaped, and the wound edges are sutured. Care is taken to create an intermammary sulcus and a breast shape that is symmetrical to the healthy side with appropriate ptosis and augmentation. Postoperatively, the abdomen is wrapped with a lap band so that the donor flap is attached to the base and the abdominal wall is strengthened to prevent the formation of an abdominal wall hernia. The glabellar area has a tip passing through it, and care should be taken to prevent local pressure from affecting the blood supply of the flap. Postoperatively, constipation and coughing are prevented, the drainage tube is removed in 4-5 days and walking starts, the stitches are removed in about 10 days and the patient can be discharged without special circumstances. Three months after the operation, after the swelling of the flap has subsided and stabilized, local stellate flap outpatient surgery is applied to reconstruct the nipple areola, and later the tattoo is colored to complete the whole process of breast reconstruction. 3. Typical case Case 1: Female, 37 years old, presented 2 years after modified radical surgery for right-sided breast cancer. Under general anesthesia, the left tipped TRAM flap was transferred for breast reconstruction, and the left inferior abdominal wall artery was anastomosed with the right dorsal thoracic artery. The outcome 1 year after surgery was good and the patient was satisfied (Figure 2). Case 2: Female, 39 years old, immediate single-tip TRAM breast reconstruction after modified radical surgery for left-sided breast cancer, 3 months postoperatively, with good shape and patient satisfaction (Figure 3). Discussion It has been nearly 20 years since Hartrampf [1] reported the application of the TRAM flap for breast reconstruction, becoming one of the most commonly used surgical procedures for breast reconstruction. Considering the blood supply of the flap, the TRAM flap should be centered on the umbilicus because the vascular penetration around the umbilicus is the thickest and abundant, while from the cosmetic point of view, the flap should be placed as far down as possible so that the abdominal scar is located on the pubic bone and covered for the undergarment. We believe that the upper edge of the TRAM flap should be located 0.5~1 cm above the umbilicus, and the upper edge of the flap should be cut obliquely toward the head, which can also bring the main periumbilical vascular penetrating branches into the flap. the lower edge of the TRAM flap should take into account that the donor area can be sutured directly, especially for young patients, the abdominal skin is originally tense and lacks sagging, and the lower edge of the flap should be moderately shifted upward to prevent wound dehiscence or partial necrosis of the skin in the donor area . In one patient, we placed the lower edge of the flap inside the pubic hair intraoperatively in an attempt to reduce the abdominal scar, resulting in postoperative necrosis in the middle of the caudal side of the apron-like flap of the abdomen, which healed only after the wound was replaced with a skin graft. the extent of the TRAM flap is within the anterior superior iliac crest on both sides, that is, it is limited to the extent of the blood supply of the inferior abdominal wall vessels and the superficial abdominal wall vessels, beyond which the blood supply area of the superficial iliac vessels will be brought into the flap and become the flap cause of partial necrosis. To reduce the distortion of the tip, the contralateral rectus abdominis muscle on the reconstructed side was chosen as the muscle tip. Application of the through branch TRAM flap with partial excision of the rectus abdominis muscle and preservation of as much of the rectus abdominis muscle and its sheath as possible in the abdomen is an important measure to prevent abdominal complications such as abdominal tenderness and abdominal wall hernias. Recent anatomical studies [6] and clinical experience [2] have shown that the lateral portion of the rectus abdominis muscle is also innervated, and preserving part of the rectus abdominis muscle is beneficial in strengthening the abdominal wall tension.Hartrampf [4] investigated the changes in abdominal wall tension after breast reconstruction with TRAM flap showed that abdominal muscle tension decreased within six months after surgery, but still maintained sufficient abdominal wall tension, and after six months muscle tension gradually recovered, and reported 6 patients delivered successfully after surgery, and one case was a twin. Therefore, the use of intramuscular separation technique and the correct surgical operation method are more important than the debate of transfer with tip or free graft [8]. The application of the TRAM flap for breast reconstruction also acts as an abdominal wall reshaping for the abdominal donor area, especially for middle-aged women, so the principles of abdominal donor area management are consistent with abdominal wall reshaping. We close the anterior rectus abdominis sheath with the same partial suture of the contralateral anterior rectus abdominis sheath to maintain symmetry of abdominal wall tension and to position the umbilicus in a median position. Recently, Hein [7] et al. folded the anterior rectus abdominis sheath on both sides and simultaneously folded the inferior abdominal wall fascia over the groin on both sides to constrict the lower abdomen. The umbilicus was fixed to the anterior rectus abdominis sheath, and a “Y” shaped hole was made in the umbilicus at the midline of the skin, and the fatty tissue around the inner skin cavity was cut away so that the newly formed navel would have a deep depression. During the operation, part of the fat in the middle of the upper abdomen is cut out to form a subcutaneous depression, and the abdomen is fixed in the middle of the abdomen and both sides of the rib abdomen with the anterior sheath to simulate the shape of a young woman’s abdomen. The method of breast contouring varies depending on the mastectomy style. There are transverse and longitudinal settings of the flap, and single-tip TRAMs are mostly set longitudinally [2]. In patients undergoing modified radical surgery, the pectoralis major pectoralis minor muscle is preserved, the morphology of the anterior axillary fold is intact, and the flap is set internally superiorly and inferiorly, with emphasis on the lateral curvature of the reconstructed breast. In patients after radical or extended radical surgery, the pectoralis major muscle is removed, the chest tissue is severely deficient, and the reconstruction of the chest requires filling the depressions in the subclavian and axillary areas and shaping the spherical body of the breast, with the flap set up in an external superior-inferior setting, focusing on highlighting the anterior axillary fold and the curvature of the breast. In patients with severe chest tissue loss, the flap needs to be fixed to the medial aspect of the upper arm to simulate the stop and shape of the pectoralis major muscle. In this group of patients, the tissue requirement is large, and since the safe blood supply of the single-tipped TRAM flap is zones 1, 2, and part of zone 3, which accounts for 70% of the entire flap, the single-tipped TRAM flap is often too inadequate and can be selected as a double-tipped TRAM, VRAM, or additional vascular anastomosis (super-charge), free TRAM, and other procedures. Considering the damage to the rectus abdominis muscle caused by the double-tipped TRAM, we generally choose the additional vascular anastomosis. With the correct operation method and safe application of TRAM flap, we can reconstruct a breast with realistic shape and symmetry with the healthy side and relieve the patient’s physical and mental pain. How to improve the reconstructive and cosmetic surgery aspects to restore the sensation of the reconstructed breast [7], especially the restoration of sexual sensation, and improve the morphology of the reconstructed breast still needs to be further investigated.