Mastopexy with the splitting of the upper pectoral muscle and inferior muscle flap Mastopexia com splitting de músculo peitoral superior e cinta muscular

a technique with biplanar dissection of the pectoralis major muscle, creating a superior envelope for the prosthesis’s inclusion in this space. The modification of this, associated with Daniel’s lower flap, with low rates of complications. The is to describe the muscle splitting technique described by Kahn, performed in combination with the lower pedicle flap described by Daniel in the augmentation mastopexies. Methods: Description of the technique and retrospective analysis, through medical records, of patients submitted to this surgery at the Dr. Jerônimo Clinic, located in Ibitinga/ SP. Results: We analyzed 192 patients, with a mean age of 43 years. The procedure average time was 150 minutes. There were 21 complications, such as seroma, unaesthetic scarring, asymmetries, and epidermolysis. This technique is a therapeutic arsenal for mastopexies. It has the advantage of not presenting complications related to the total and subglandular submuscular plane. It presents the naturalness of the contour in the upper pole, absence of lateralization, and prosthesis movement. Furthermore, the association with a lower flap provides greater protection and support to the implant, reducing the chance of ptosis. Conclusion: The technique presented good results, with low rates of complications. It is evidencing a viable, safe and reproducible alternative to perform augmentation mastopexy.


INTRODUCTION
Mastopexies are among the most performed aesthetic procedures globally but still have a high patient dissatisfaction rate, with high rates of secondary surgeries for review (8-20%) 1,2 . The difficulties associated with this procedure derive from the antagonistic principle that the two techniques involved in it exert. The increase, due to tissue expansion, while mastopexy involves remodeling with excision of parenchyma and skin 3 . Several techniques have been described in consideration of those above and the search for improvement and a lower complication rate. Type of incision, dissection plan, envelope model are some of the variables in which they are sought as an alternative [4][5][6][7][8][9] .
Kahn described a technique with biplanar dissection of the pectoralis major muscle, creating a superior envelope for prosthesis inclusion in this space. Some of this modality's advantages are the transition and smoother contours and more accelerated postoperative recovery 10 .
In our clinic, located in Ibitinga, in São Paulo's interior, we chose to perform this technique in association Introdução: As mastopexias estão entre os procedimentos estéticos mais realizados no mundo, porém ainda apresentam alto índice de insatisfação dos pacientes. Várias técnicas foram descritas na busca pelo aperfeiçoamento da técnica. Kahn descreveu uma técnica com dissecção biplana do músculo peitoral maior, criando um envelope superior para a inclusão da prótese neste espaço. A modificação desta, associada ao retalho inferior descrito por Daniel  association of the lower support flap of the pectoralis major muscle with a superior split of the same. This study was conducted according to the Declaration of Helsinki for human studies.

Skin marking
With the patient in an orthostatic position, the thorax's midline, the breast meridian and the inframammary groove are defined. The upper edge of the areolas is marked exactly as described by Pitanguy in 1962 13 , projection of the inframammary groove in the breast meridian, point A. Then points B and C are determined by digital clamping maneuver, and point D is located in the previously marked breast groove ( Figure 2).

Anesthesia and surgical technique
General anesthesia and infiltration in the breasts with 1% xylocaine solution and 1:200,000 adrenaline are used.
With the patient positioned in the supine position and a slight elevation of the back (30 degrees), the areolar incision is made with the Schwartzman maneuver, crossing the region from point A to points B and C. It is made resection in the larger or smaller keel, depending on breast size and preoperative planning, until reaching the pectoralis major muscle's aponeurosis, preserving the lateral and medial pillars using the electric scalpel.
The upper implant pocket's preparation is performed through the subfascial plane's dissection until the breast's areolar part. From this location, the pectoralis major muscle is split, reaching a size close to that of the implant base. The lower pocket is performed through an incision in the pectoralis major muscle, in the sense of its fibers, 3 cm from its inferior insertion, towards the sternal and axillary region ( Figure 2).
Rigorous hemostasis and positioning of the prosthesis are performed, where the upper part will be in the subfascial plane and the lower part in the submuscular plane. The starting point of breast assembly is performed by joining the lateral abutments with the pectoralis major muscle. Subsequent stitches are only in breast tissue. Both were using Vicryl 2-0.

Partial release of the areolar dermis
Cutaneous excess is assessed using digital clamping and tailor tacking using 2-0 nylon. With these maneuvers, a greater ascension of the nippleareola complex (NAC) is achieved (Figure 2). With the evaluation of the shape and symmetry of the breasts, cutaneous excesses are removed. To prevent the breast scar from becoming too long, lateral and medial  compensations are performed, ending with an inverted T scar. The nipple-areola complex is repositioned, and it must be located at the apex of the cone and with an approximate distance of 6cm from the new mammary fold. The dermis suture is made with simple inverted stitches and on the skin with intradermal stitches using 4-0 monocryl thread. Drains are not used, and hospital discharge usually occurs 8 hours after the surgery, using surgical mesh for 30 days.
The dermis suture is done with simple inverted stitches and on the skin with intradermal stitches using 4-0 monocryl thread.
No drains are used, and hospital discharge usually occurs after 8 hours of completing the surgery, using surgical mesh for 30 days.

Implants
Round, high-profile silicone implants with polyurethane texture of the Brands Silimed and Polytech were used to perform the present study.

RESULTS
A total of 192 patients were submitted to mastopexy with an upper split implant and lower pectoralis muscle fixation (double space) ( Table 1). The patients had a mean age of 43 years, ranging from 19 to 68 years. Bmi ranged from 16-38Kg/m 2 , with an average value of 23Kg/m 2 . The average time of the procedure was 150 minutes. The volume of the implants ranged from 125 to 625ml, with a mean value of 265ml. Seven patients presented seroma in the postoperative period (3.6%), and in three (1.5%), the condition persisted for six months even after clinical treatment with compressive mesh, oral corticosteroids and antibiotic therapy. Thus, we opted for the bilateral removal of implants. Two patients have already undergone a new procedure with prostheses' inclusion, with the same technique described here, the same brand and volume as the previous ones.

Characteristics of patients
There were unaesthetic scars (2.6%) in five cases, two in areolar contour and three in the horizontal part, which required a new approach under local anesthesia and sedation, 12 months after the first surgery. Three patients presented small sufferings of the nipple-areola complex (1.5%), with epitheliosis, which was already readdressed, with scar revision. Breast asymmetries were observed in 5 patients (2.6%). Three underwent a surgical procedure to release the lower part of the breast's muscle that presented the prosthesis in the highest position. One episode of hematoma was described (0.5%) but without clinical repercussion and need for approach. There were no cases of infection, contracture or skin necrosis.
Postoperative follow-up ranged from 1 to 13 months, and in all cases, it was noticed the maintenance of the projection in the upper pole of the breast, with satisfaction with the aesthetic result, with no recurrence of the breast ptosis (Figures 3 to 6).

DISCUSSION
Since the original description by Gonzales-Ulloain 1960 14 and Regnaultin1966 15, breast augmentation combined with mastopexy remains a challenging and controversial procedure in plastic surgery, not only for its results but also for its potential complications 16,17 .
The smooth transition in the breast's upper pole and natural appearance made us choose to make a sandwich of the pectoralis major muscle in its part above the areola, as recommended by Khan in 2007 10 . This technique provides better coverage of the upper and lateral pole 18 ; another advantage is that there is no dissection of the muscle fibers of its insertion, preserving function and decreasing the chance of lateralization, displacements of the prosthesis and deformities of animation 19 .
In this superior plane, the complications related to the inclusion of the prosthesis in the total submuscular plane are avoided, such as: displacements, deformities, asymmetries and rupture; and associated with subglandulars as visible, palpable and rippling prostheses 18 . One of the common concerns among the authors is to avoid mammary ptosis. Daniel's pectoral muscle flap in 1994 11 provides muscle support in the lower pole of the breast, preventing the implant's ptosis and its displacement to the armpit, maintaining the upper pole of the projected breast. The prosthesis is placed in double space, with its lower pole submuscular and the rest in the subfascial space. In addition to decreasing the chance of ptosis, this lower flap offers additional coverage and protection, reducing the chance of extrusion and exposure of implants 20 .
We opted for silicone-polyurethane based on studies that suggest that its velcro sticks to the breast tissues with less displacement of the same within the manufactured pocket and lower rates of capsular contracture 21 .
The total number of complications presented, 10.9% of the cases, is lower than that reported in the literature and the number of secondary surgeries performed -3.15%. Asymmetry and seroma were the main causes of new approaches. The first, mainly related to the lower pedicle preparation, occurred in 2.9% of the patients, but 80% of them were reoperated. The surgical procedure performed was to enlarge the musculature release since the complaint was the highest prosthesis concerning the contralateral breast. Seroma occurred early in 1.5% of patients and remained despite clinical therapy. Secondary mastopexy was chosen in 100% of them, using the same surgical technique. The other complications, such as unaesthetic scarring and epidermolysis of NAC, were managed with small procedures performed under local anesthesia 17 .
The postoperative evaluations show the effectiveness of this technique, with minimal ptosis rate, one of the most cited complications in mastopexies. There were no cases of flattening of the mammary cone, which were more related to periareolar incisions 4 . The patients were satisfied with the surgical outcome.
The learning curve did not show a hindrance, with an average time of 150 minutes. The greatest difficulty at the beginning of this technique was dissection for bipartition of the pectoralis major muscle in its upper part.
The limitations present in this study are the retrospective character and be based on a single institution and a single surgeon's experience.