Chapter-2-Breast-Augmentation_Subglandular-Subfascial-Submus

2

Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

C H A P T E R

Chet Mays and Bradley Calobrace

DEFINITION

Subfascial Implant

■■ Advantages to placing the implant in a subfascial pocket ( FIG 2 ) include the following 1,3 : 23 ■■ It avoids implant deformation or distortion (animation deformity) that can be seen in the subpectoral position. ■■ This position provides additional soft tissue coverage between the implant and the skin as compared to the sub- glandular pocket. ■■ Fascia provides additional support to minimize implant edge visibility and palpability seen most commonly with subglandular placement. ■■ Fascia provides support of implant especially in the upper pole minimizing excess implant movement and potential rotation with shaped implants. ■■ Less postoperative pain as compared to submuscular placement ■■ Fascia provides a distinct layer separating the implant from the overlying breast parenchyma. ■■ The disadvantages of a subfascial pocket include the following: ■■ Less soft tissue coverage compared to submuscular coverage

■■ A critical choice in breast augmentation is where to place the implant pocket. ■■ Subglandular ■■ Subfascial ■■ Submuscular (for purposes of this paper, submuscular refers to below the pectoralis major) ■■ Implant choice, size, and location are based on a variety of patient qualities. ■■ A biodimensional analysis is essential in determining the optimal implant type, size, and pocket location. There are many methods of evaluation. The High Five system described by Tebbetts is a systematic approach that illus- trates the most important aspects of evaluation, including the following: 24 ■■ Base width of breast ■■ Base width of implant ■■ Nipple to fold distance ■■ Estimate of final implant volume ■■ Pocket determination based on skin pinch thickness Subglandular Implant ■■ The subglandular implant is deep to the breast tissue and superficial fascia, but superficial to the deep pectoralis fas- cia, coming to rest on the inframammary fold ( FIG 1 ). ■■ The subglandular pocket has long been regarded as the most natural pocket. 2 ■■ The advantages of subglandular implant placement include the following: ■■ It avoids implant deformation or distortion that can be seen in the subpectoral position ■■ Enhances the improvement in the constricted or ptotic breast ■■ Allows an easier dissection plane ■■ Decreased postoperative discomfort ■■ Allows access to the inframammary fold (IMF) as the superficial and deep fascial components merge ■■ There are some disadvantages of the subglandular pocket, which include the following: ■■ Pocket with the least soft tissue coverage to disguise the implant ■■ Increased visibility or palpability of implant with wrin- kling or rippling ■■ Higher capsular contracture rate ■■ Less support and stabilization of the implants, especially shaped devices, compared to subfascial or submuscular pockets

FIG 1 • Subglandular implant placement is deep to the breast tissue but superficial to the pectoralis fascia.

1298

Part 4 Plastic Surgery of the Breast

■■ Enhanced coverage of the implant ■■ Reduced issues with wrinkling ■■ Sloping natural upper pole ■■ Enhanced support for the breast implant ■■ Enhanced radiographic imaging with mammogram 5,22 ■■ The disadvantages of a submuscular pocket include the following: ■■ Animation deformity ■■ Increased risk of implant superior malposition with waterfall deformity ■■ Increased postoperative pain ■■ Limited expansion of the lower pole of breast (required to expand constricted and ptotic breasts) ■■ The most significant attribute of the submuscular pocket is in providing maximum soft tissue coverage for the implant. The widespread use of saline implants and wrinkling issues led to surgeons looking for improved implant coverage. After the moratorium on silicone was lifted, surgeons in the United States continued to use the submuscular pocket with mostly smooth and to a limited extent textured silicone implants. 6 ANATOMY ■■ An understanding of the breast blood and nerve supply is critical when performing breast surgery ( FIG 4AB ). ■■ Muscular attachments are shown in FIG 4C . ■■ The breast is a skin appendage contained within layers of the superficial fascia. ■■ The superficial layer of this fascia is near the dermis and is not distinct from it. ■■ The deep layer of the superficial fascia is more distinct and is identifiable on the deep surface of the breast when the breast is elevated in a subglandular augmentation mammoplasty.

Pectoralis major muscle

Pectoralis major fascia

Implant

FIG 2  • Subfascial implant placement is deep to the breast tissue and the pectoralis major fascia but superficial to the muscle.

■■ More challenging dissection to separate deep pectoral fas- cia from underlying muscle while keeping fascia intact. ■■ Higher rateof capsular contracture compared tosubmuscular Submuscular Implant ■■ Advantages to placing the implant in a submuscular pocket ( FIG 3 ) as compared to placement in the subglandular or subfascial pocket include the following: ■■ Lower capsular contracture rates 1,4

Pectoralis major

Pectoralis major

Pectoralis minor

Implant

FIG 3  • A. Submuscular position of the implant with overlying pectoralis muscle and breast parenchyma. Note that the released inferior edge of the pectoralis major allows lower pole expansion ( arrow ). B. Anterior view of the implant placement below the pectoralis major. A B

1299

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

Thoracoacromial artery

Subclavian artery

Axillary artery

Pectoral branch of thoracoacromial artery

Superior thoracic artery Internal thoracic artery

Lateral thoracic artery

Perforating branches

Lateral mammary branches of posterior intercostal arteries

Medial mammary branches

Lateral mammary branches

A

Lateral pectoral nerve

Thoracoacromial artery

Axillary artery

Medial pectoral nerve

Median nerve

Medial brachial cutaneous nerve

Pectoralis major Pectoralis minor

Intercostobrachial nerve

Thoracodorsal nerve

Long thoracic nerve

B FIG 4  • A. Arterial blood supply of the breast. B. Nerve branches supplying the breast.

1300

Part 4 Plastic Surgery of the Breast

Pectoralis major

Pectoralis minor

FIG 6  • Histologic slide of the inframammary fold (IMF) showing the superficial and deep fascia fusing together. 7

■■ The subfascial pocket is deep to this deep pectoral fascia but superficial to the underlying muscle. ■■ This fascia is thin and more fragile in the lower two-thirds of the pectoralis muscle and becomes denser and substan- tial in the upper third of the muscle. ■■ The thin fascia in the lower aspects of the breast can make the initial subfascial dissection more challenging, which becomes easier as the dissection proceeds toward the upper pectoralis muscle. ■■ The deep fascia overlying the pectoralis and the deep layer of the superficial fascia underlying the breast unite with the dermis to form the IMF ( FIG 6 ). 7 PATIENT HISTORY AND PHYSICAL FINDINGS ■■ Initial consultation should evaluate the patient’s goals and anticipated results with the breast augmentation. ■■ A thorough history and physical should be done to iden- tify any risk factors for the procedure, including bleeding or clotting disorders. ■■ Any history of breast lumps, masses, or breast disease should be elicited. ■■ A family history is required. ■■ In planning for optimal implant pocket selection, it is important to determine the desired appearance or “look” the patient is seeking. ■■ The submuscular pocket is more likely to create a smooth, sloping upper pole with minimal roundedness in the upper pole. ■■ A patient desiring a more rounded upper pole with a more obvious “implant appearance” with implant shape visibility may prefer a subglandular implant, provided there is adequate soft tissue coverage. ■■ The subfascial approach can provide a compromise between the two; the implant will be in a plane similar to the subglandular, but the additional fascia layer will minimize implant edge visibility and palpability that can be seen with the subglandular pocket. ■■ The preoperative exam of the breast augmentation patient will guide the surgeon’s implant selection and pocket place- ment. The physical exam measurements should include the following ( FIG 7 ):

■■ There is loose areolar tissue between the deep layer of the superficial fascia and the fascia to cover the pectoralis major that and to cover the adjacent rectus abdominis, serratus anterior, and external oblique muscles. ■■ The deep pectoralis fascia has its origin on the clavicle and sternum, extending toward the lateral border of the muscle to form the axillary fascia ( FIG 5 ). ■■ It continues down to cover the latissimus dorsi muscle, rectus abdominis, serratus anterior, and external oblique. C FIG 4 (Continued)  • C. Muscular attachments to the chest. The pec- toralis major is removed on the right side of the picture revealing the underlying pectoralis minor.

Pectoralis major muscle

Skin

Retromammary space with overlying pectoralis fascia

Mammary glands

Ducts

Suspensory ligament

Fat FIG 5 • Breast anatomy showing pectoralis fascia posterior to the breast tissue.

1301

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

■■ If the soft tissue coverage is lax and poor quality or if the implant selected is deemed at risk for wrinkling, a pinch test greater than 3 cm is more reliable in providing ade- quate coverage and minimizing the risk of rippling. ■■ Adequate soft tissue coverage in the upper pole in a sub- glandular augmentation will camouflage the transition between the breast and implant, aiding to a smooth natu- ral upper pole. ■■ The deep fascia overlying the implant in the subfascial pocket will provide additional support and coverage in the upper pole and minimize the implant edge visibility, which can be seen if implants are placed in the subglandu- lar pocket with limited upper pole coverage. ■■ If the patient prefers a full, rounded upper pole with an obvious transition between her implant and soft tissue, a subglandular implant would be preferred even if the pinch test is less than 2 cm. ●● One must have a discussion regarding visible and pal- pable rippling of the implant if placing the implant sub- glandular and the pinch test is less than 2 cm. ■■ Capsular contracture can be reduced by using a tex- tured implant in the subglandular position, but one must consider the risks of rippling with textured implant in a patient with inadequate upper pole coverage with a pinch test of less than 2 cm. 1 Physical Assessment ■■ Assess for all asymmetries, including breast volume, IMF, nipple-areolar complex (NAC), and chest wall. ■■ Chest wall (skeletal and muscle) abnormalities or asymme- tries are often underappreciated and can significantly alter the final result ( FIG 9 ). 8 ■■ Pectus excavatum occurs occasionally, whereas pectus carinatum and Poland syndrome are rare. 9 ■■ Central deformities are typically ameliorated sufficiently by breast augmentation alone. ■■ Deep pectus excavatum deformities can be treated simul- taneously with a custom solid silicone implant made from a plaster mold, although most patients decline this option. ■■ Poland syndrome (absence of sternal head of pectoralis muscle) is best addressed with subglandular augmenta- tion as the sternal head of the pectoralis major muscle is absent. When more severe, more extensive adjunctive procedures, such as tissue expansion, fat grafting, and latissimus muscle transfer, may be required. 10 ■■ Hemithorax asymmetry due to differences in shape, pro- trusion, or regression can create an uneven breast founda- tion, suggesting different size implants despite equivalent breast volumes.

SSN:N

SSN:N

BW

BH

N:IMF

IMD

FIG 7  • Necessary physical exam breast measurements.

■■ Breast width (BW) ■■ Sternal notch to nipple (SSN:N) ■■ Breast height (BH) ■■ Nipple to IMF (N:IMF) at rest and under maximal stretch. ■■ Upper pole pinch (UPP), medial pinch (MP), and lateral pinch (LP) ■■ Intermammary distance (IMD) Pinch Test ■■ A key point of the exam is the upper pole pinch test. ■■ A pinch test of less than 2 cm indicates the need for a submuscular placement of the implant to avoid noticeable rippling ( FIG 8A ). ■■ If the pinch test is more than 2 cm (1 cm of soft tissue thickness), the patient is a candidate for a subglandular or subfascial pocket ( FIG 8B ). (The deep fascial layer will provide additional coverage over the implant to allow for subfascial placement.) ■■ Implant selection impacts adequacy of soft tissue coverage. Keep in mind the thinner the soft tissue, the greater the risk of implant palpation and rippling. ■■ Some implants are prone to more wrinkling, including underfilled saline implants and textured devices. ■■ We require a pinch test of more than 2 cm if placing the implant subfascially or subglandularly, where the soft tis- sue coverage is firm and good quality.

FIG 8  • A. Upper pole pinch test less than 2 cm and (B) more than 2 cm.

1302

Part 4 Plastic Surgery of the Breast

Rectangular

Round

Pectus Excavatum

Asymmetric

FIG 9 • Examples of chest wall abnormalities.

■■ Unilateral prominence of the chest wall is often associated with scoliosis ( FIG 10 ). ■■ Subtle unilateral pectoralis hypertrophy should not affect subglandular or subfascial implant placement, but it could affect subpectoral placement and overall implant projection. IMAGING ■■ Screening mammography per the American College of Surgeons is recommended for patients over 40 years of age. ■■ Many plastic surgeons recommend a baseline mammogram at 35 or older prior to a breast augmentation, especially if a family history is present. ■■ Any additional diagnostic studies are guided by the preop- erative exam.

■■ Any palpable mass requires evaluation, usually with a diag- nostic ultrasound and/or mammogram. SURGICAL MANAGEMENT ■■ The preoperative evaluation and decision-making are a critical step in achieving optimal outcomes in breast augmentation. ■■ Capsular contracture is the leading indication for revision breast surgery after a breast augmentation and every effort should be made during planning and execution to minimize the risk of capsular contracture postoperatively. Placement of breast implants in the submuscular pocket has consis- tently demonstrated reduction in capsular contracture rates compared with the other pocket choices. 1,4 ■■ Validated steps to reduce this risk include the following: ■■ Nipple shields 11 ■■ No-touch technique 12 ■■ Use of an insertion sleeve 13 ■■ Pocket irrigation with triple antibiotics 14 ■■ Inframammary incisions 4 ■■ Use of textured implants 1,4 Preoperative Planning Incision ■■ The decision on incision placement is based on a variety of variables: ■■ Patient and surgeon preferences ■■ Anatomic considerations

FIG 10  • Left chest wall prominence compared to the right chest wall.

1303

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

■■ Implant type and size ■■ Issues of capsular contracture, breast-feeding, and NAC sensation ■■ There are many potential advantages of the inframammary approach, including the following: ■■ Well-hidden scar in the fold of the breast ■■ Incisional length is unlimited, thus can accommodate any and all implant choices ■■ Excellent visualization for dissection of the implant pocket ■■ The ability to control the IMF position during incision closure ■■ Can be used for any complication revision ■■ Lower capsular contracture ■■ Minimal issue of a scar contracture creating deformity ■■ Potentially less nipple sensation changes ■■ Potential disadvantages of the inframammary incision include the following: ■■ The scar is located on the breast ■■ Scar may be more visible if breast fold is absent or if the scar becomes pigmented ■■ Must determine final IMF position preaugmentation and place scar precisely in planned new fold. ■■ Scar position more vulnerable to irritation from the bra ■■ There are many potential advantages of the periareolar approach, including the following: ■■ Scar can be camouflaged in the areolar border ■■ Direct visualization and access into the breast pocket ■■ Can lower the IMF to any location without predetermin- ing location ■■ Central access allows use in most revision cases with optimal visualization and access to the upper pole of the breast ■■ Access for parenchymal breast scoring in constricted breast deformities ■■ Potential disadvantages of the periareolar incision include the following: ■■ The scar is located on the breast ■■ Access is through a tunnel and may limit visualization in dense, heavy breasts ■■ Cannot use if areolae are too small ■■ Poor scarring possible and can create significant deformities ■■ IMF control sutures not possible when IMF is lowered ■■ Transection of breast ducts may increase bacterial contamination ■■ Potentially higher capsular contracture rates 15 ■■ Good candidates for the inframammary approach may include the following: ■■ Small areola ■■ When controlling IMF is desired ■■ Indistinct areolar border ■■ Desire for no scar on the breast ■■ Potentially when placing larger implants ■■ Desire future breast feeding as interference with lactation has been implicated with periareolar incision. 5 ■■ Concerns with nipple sensation, although no strong data to support this concern. 3,16 ■■ Good candidates for the periareolar approach may include the following: ■■ Very distinct areolar borders present

■■ When areola large enough to accommodate implant and avoid implant trauma ■■ When performing a concurrent mastopexy ■■ Indistinct or absence of IMF to hide scar ■■ When lowering IMF (IMF position does not need to be predetermined) ■■ Treatment of tuberous breasts (parenchymal scoring, IMF lowering) ■■ The incision should be as small as possible but large enough to dissect the pocket and place the implant without distort- ing or injuring the device. ■■ Incision length ranges include 3 to 4.5 cm for saline implants, 4 to 6 cm for silicone round implants, and 4.5 to 7 cm for shaped cohesive silicone implants. 17 ■■ The length of the incision would be smaller with saline than with silicone implants. Factors requiring increased incision length include the following: ●● Shaped implants (cohesiveness and gel distribution) ■■ When using the periareolar approach, the incision is made around the areola and the dissection is carried inferiorly the appropriate distance to accommodate the selected breast implant. ■■ However, when the approach is through an IMF incision, the final position of the fold postaugmentation must be predetermined so the incision can be placed accurately in that location. ■■ Before surgery, the IMF is identified and marked in the sitting position ( FIG 11A ). To determine the true IMF posi- tion, the breast is autorotated inferiorly to identify the inferior extent of the attachments of the IMF ( FIG 11B ). ■■ The distance measured from the nipple to the true fold under maximal stretch assesses the amount of lower pole skin available to accommodate the selected implant. ■■ The amount of lower pole skin required and the ultimate position of the fold is a function of many factors, including the type of implant (saline vs silicone, round vs shaped), size of implant, pocket location, and the strength and stability of the soft tissue of the lower pole. ■■ An acceptable standard that can be used is to follow the guidelines that an implant with a base diameter of 11 cm requires 7 cm, a base diameter of 12 cm requires 8 cm, and a base diameter of 13 cm requires 9 cm from nipple to fold. 18 ■■ Another useful method of estimating fold position is based on implant height and projection and can be used for round or shaped implants 17 : ■■ Optimal nipple to IMF distance = (1/2 implant projec- tion) + (1/2 implant height) ■■ IMF lowering = (optimal nipple to IMF distance) − (mea- sured nipple to IMF distance) ■■ If the measured nipple to fold distance is less than the desired or optimal distance, the fold will need to be lowered. ■■ Keep in mind that textured and smooth implants have dif- ferent effect on the lower pole skin and fold over time. A larger smooth implant will lead to more stretch on the lower pole compared to a smaller or textured implant. ●● Implant volume ●● Implant texture ●● Silicone compared to saline ●● Increased gel cohesiveness (silicone gel firmness) ●● Increase implant projection

1304

Part 4 Plastic Surgery of the Breast

Inframammary fold

A

FIG 11  • A. The inframammary fold is a natural boundary where the chest and the breast meet. B. Autorotation of the breast. N:IMF is 6 cm at rest. N:IMF is 8 cm on stretch/autorotation.

Approach

Pocket Control

■■ Pocket control is key and begins during preoperative mark- ings to design the pocket size necessary to accommodate the selected implant. ■■ Controlling the pocket involves placement of the IMF, defin- ing the medial and lateral pocket margins. ■■ This creates the desired cleavage and prevents lateral migration or malposition of the implant. ■■ Whereas smooth implants often are designed with a larger pocket to allow for implant mobility and perceived softness, pocket design should be more limited when using a textured implant. ■■ Excess movement can lead to irritation and seroma formation. ■■ When using a shaped textured implant, a controlled pocket is even more essential to minimize the risk of implant rota- tion postoperatively. ■■ This requires defining the lateral, medial, and inferior as well as the superior border and limiting the pocket to only what is required to accommodate the shaped device. ■■ The implant and pocket should ultimately have a “hand- in-glove” fit. 19 Positioning ■■ Patients are placed on the operating room table in the supine position. ■■ The arms are secured to the arm board at approximately 45 degrees to stabilize the patient in the upright position. Actual arm placement is between 45 and 60 degrees ( FIG 12 ). ■■ Some surgeons place the arms directly by the patient’s side. ■■ Having the arms abducted to 90 degrees should be avoided because this does not allow the breasts to be in a relaxed position when sitting the patient up to check adequacy of implant placement and soft tissue redraping.

■■ Before surgical preparation, 50 mL of a local field block of 1/4% lidocaine, 1/8% bupivacaine, and 1:400 000 epineph- rine is injected into breast (Table 1). ■■ A 20-mL syringe with a 22-gauge spinal needle is used to inject the anesthetic into the dermis along the planned incision line, deep to the dermis along the IMF, the medial pectoral border, the anterior axillary line, and deep to the breast parenchyma, in a fanning fashion throughout the area of planned pocket creation ( FIG 13 ). ■■ These injections provide assistance not only in operative hemostasis but also in the management of postoperative pain. ■■ This is less important in the subglandular augmentation as postoperative pain is significantly less than with a sub- muscular augmentation.

FIG 12  • Arms abducted at approximately 45 to 60 degrees in supine position.

1305

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

Table 1 Breast Local Anesthetic Formula Drug

Amount  25 mL  25 mL  25 mL  25 mL 100 mL

½% lidocaine plain

½% lidocaine/1:200 000 epinephrine ½% bupivacaine/1:200 000 epinephrine

Injectable saline

Total concentration : ¼% lidocaine, 1/8% bupivacaine, 1:400 000 epinephrine

FIG 13 • Breast infusion with 20-cc syringe and a 22-gauge spinal needle.

T E C H N I Q U E S

■■ Subglandular and Subfascial Placement ■■ The distinction between the subglandular and the subfas- cial plane is subtle and opinions differ on whether it is of clinical importance. ■■ The common aspect is both involve dissection superficial to the muscle and avoid both, the animation deformity associ- ated with the muscle and the limitation the muscle plays on the ability of the implant to expand the breast envelope. Inframammary Fold Incision ■■ A variety of incisional approaches to the subglandular, subfascial, or submuscular pocket are possible, the infra- mammary fold (IMF) being the most common. ■■ This incision is performed the same for both subglan- dular or subfascial pockets. ■■ After determining the IMF position (either the native true fold position or the planned lowered position), a para- median line is drawn through the center of the breast and bisects the newly drawn IMF. ■■ The incision’s medial extent begins 1 cm medial to the paramedian line and extends laterally for the appropriate distance, as previously described based on the implant type ( TECH FIG 1A ). ■■ The incision is made with a no. 15 blade through the skin to the mid-dermis ( TECH FIG 1B ).

■■ Dissection is then carried out with electrocautery through the skin and subcutaneous tissue, beveling superiorly while rotating the breast off of the chest wall. ■■ Once dissection has been carried superiorly for 1 cm, the dissection is carried through the superficial fascia and toward the chest wall. ■■ The beveling preserves a small cuff of superficial fascia at the incision, which ensures the fold is not inadvertently lowered and also provides a cuff of Scarpa fascia that will prove useful during closure ( TECH FIG 1C ). ■■ As dissection proceeds toward the chest wall, a constant upward retraction of the breast tissue is maintained, exposing the pectoralis major with its overlying fascia ( TECH FIG 1D ). ■■ The upward retraction of the breast tissue is key, as the suspensory ligaments of the breast concomitantly elevate the muscle to expose the muscle edge. ■■ The only distinguishing characteristic is at the level of the IMF incision, dissection begins over the pectoralis fascia for the subglandular pocket or deep to the fascia for a subfascial pocket. ■■ The elevation of the subglandular pocket is superficial to the pectoralis fascia, and the elevation of the sub- fascial is deep to the breast and fascia, but superficial to the muscle.

TECH FIG 1  • A. Paramedian line drawn from the nipple to the IMF. Note the 5 cm incision length. B. 5-cm inframammary incision. C. Cuff of Scarpa fascia. D. Upward rotation of the breast with retractor exposes the underlying pectoralis muscle.

T E C H N I Q U E S 1306 Part 4 Plastic Surgery of the Breast

Pocket dissection

■■ The dissection should be directed in an inferior direc- tion to ensure that the nipple-areolar complex (NAC) is not inadvertently undermined during dissection and the blood supply compromised. ■■ Dissection proceeds either directly through the breast tis- sue (transparenchymal) to the pectoralis fascia or infe- riorly under the skin (subcutaneous) until the fascia is reached at the fold. The authors prefer the transparen- chymal approach ( TECH FIG 2D,E ). ■■ With the subcutaneous periareolar approach (like the IMF approach), the breast elevation and pocket creation begins at the fold and proceeds superiorly in the subglan- dular plane. ■■ The IMF is a fusion of the deep fascia attached to the pectoralis and the superficial fascia of the breast. ■■ Care is taken to prevent disruption of the IMF as the breast is elevated off the pectoralis fascia. ■■ If the transparenchymal periareolar approach is used, the dissection is directed through the breast down to the pectoralis fascia. ■■ The subglandular pocket is then developed as an infe- rior flap and superior flap with its overlying breast tissue, creating a continuous pocket superficial to the pectoralis muscle fascia. TECH FIG 2  • A. Periareolar incision noted with dark purple line . B. Periareolar incision along inferior border of NAC. Solid black line is the IMF. C. Periareolar incision along inferior border of NAC with counter tension. Be careful not to aggressively undermine the NAC. Solid black line is the IMF. D. Schematic of the transparenchymal and subcuta- neous approach. E.  Periareolar transparenchymal approach with electrocautery. Solid black line is the IMF.

Periareolar incision

D

Transparenchymal dissection

Subcutaneous dissection

Periareolar Incision

■■ Development of the periareolar incision differs slightly based on either subglandular or subfascial implant placement is intended. The differences are distinguished below. ■■ The planned incision location is marked directly on the border of the inferior areolar and breast skin with a series of dots. ■■ The dots are used instead of a line for more accurate visualization of the exact areolar border. ■■ It is most important to follow the exact outline of the areolar border even if irregular because any deviation off the border to smooth the incision outline leads to a more visible scar ( TECH FIG 2A ). ■■ The planned incision should extend equidistance medial and lateral from the midline but not to exceed half of the circumference of the areola. ■■ With the skin placed under tension by the assistant, the incision is made precisely on the areolar border with a no. 15 blade through the skin to the mid-dermis ( TECH FIG 2B ). ■■ Dissection then proceeds through the deep dermis and breast parenchyma with electrocautery. ■■ The skin edges are retracted inferiorly and superiorly, and dissection is carried down through the parenchyma toward the pectoralis fascia ( TECH FIG 2C ).

Subglandular Pocket

1307

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

T E C H N I Q U E S

Breast tissue

Deep pec fascia

Pectoralis fascia

Pectoralis major

A

TECH FIG 3 • A. Elevation of the overlying breast tissue with under- lying pectoralis muscle and fascia. B. Subglandular pocket with pecto- ralis muscle/fascia visible posterior to the pocket.

the lateral action of the forceful pectoralis muscle contraction. ■■ As one carries the subglandular dissection medially, the midline can quickly be violated due to the lack of sternal muscle attachments that usually limit the dis- section in the submuscular plane. ■■ The fascia is adherent to the underlying pectoralis muscle as the sternum is approached in the subfas- cial dissection and will provide some limitation to medial overdissection compared to the subglandular pocket. ■■ Overdissection can lead to implant medialization and the potential for postoperative symmastia. This is especially true when the chest wall is concave or slant- ing medially. Special caution with limited medial dis- section is warranted in these cases. ■■ Remember if IMF lowering is needed, the dissection is in the subglandular pocket, as the attachments creating the fold are superficial to the deep pectoral fascia. 20 Implant Placement ■■ Once dissection is complete, the pocket is irrigated with triple antibiotic solution (1 g cefazolin sodium, 80 mg gentamicin, 50 000 units bacitracin mixed in 500 mL of normal saline) and hemostasis is assessed ( TECH FIG 5A ). ■■ The authors as a personal preference generally remove bacitracin and add betadine solution (50 cc) to the irri- gation mixture if no allergy exists. 14 ■■ The implants are soaked in the irrigation solution before insertion. Gloves are changed and rinsed with the irriga- tion solution to remove any residue. ■■ In the authors’ practice, the implant is placed into the pocket with the assistance of an insertion sleeve such as the Keller funnel ( TECH FIG 5B ). ■■ The opening of the funnel should be cut large enough to allow easy egress of the implant through the funnel. This is confirmed by passing the implant with irrigation solution through the funnel before insertion. ■■ The implant orientation is confirmed in the funnel, and a maneuver of squeezing the implant through the funnel with pressure exerted on the back of the funnel slips the implant into the breast pocket. ■■ These maneuvers provide a “no-touch” technique, which has been associated with lower capsular con- tracture rates. 13 TECH FIG 4  • Creation of the subfascial plane. The deep pectoralis fascia is elevated with the breast tissue exposing the underlying pec- toralis major muscle.

■■ If the fold is inadvertently disrupted and the IMF lower- ing is not planned, the fold must be controlled with deep fascial sutures at the time of incision closure. ■■ Continued upward retraction of the breast will elevate the breast and its underlying superficial fascia as a single unit, leaving the deep pectoralis fascia attached to the muscle. ■■ The dissection is carried superiorly, medial and lateral to create the desired pocket ( TECH FIG 3 ). Subfascial Pocket ■■ With the subcutaneous periareolar approach (like the IMF approach), the breast elevation and pocket creation begins at the fold and proceeds superiorly in the subfas- cial plane. ■■ The IMF is a fusion of the deep fascia attached to the pectoralis and the superficial fascia of the breast. ■■ Care is taken to prevent disruption of the IMF as the breast and underlying pectoralis fascia are elevated off the underlying pectoralis muscle. ■■ If the transparenchymal periareolar approach is used, then dissection is directed through the breast down to the pectoralis fascia. ■■ The subfascial pocket is then developed as an inferior flap and superior flap of fascia with its overlying breast tissue, creating a continuous pocket superficial to the pectoralis muscle but beneath the fascia. ■■ If the fold is inadvertently disrupted and the IMF lower- ing is not planned, the fold must be controlled with deep fascial sutures at the time of incision closure. ■■ The inferior extent of the pectoralis fascia is thin and elevation is best carried out with the cut current of the electrocautery. The superior fascia is thicker and more developed providing more easily dissected plane. ■■ Continued upward retraction of the breast will elevate the fascial plane. ■■ The fascia is left attached to the overlying breast tissue and elevated as a single unit. ■■ The dissection is carried superiorly, medial and lateral to create the desired pocket ( TECH FIG 4 ). Pocket Control ■■ As with any breast augmentation, pocket control is key. ■■ Avoid overdissection of the pocket laterally to optimize medial projection of the implant and minimize lateraliza- tion of the implant. ■■ Subglandular implants have less lateral drift com- pared with submuscular implants because they lack

T E C H N I Q U E S 1308 Part 4 Plastic Surgery of the Breast

TECH FIG 5 • A. Irrigation of breast pocket prior to implant placement. B. Insertion of breast implant into subglandular pocket with Keller funnel. C. Hand-assisted implant pocket assessment and breast tissue redraping. D. Note the pocket control and the medial projection of the implant in the supine position.

■■ Once the implant is in the pocket, a finger-assisted assess- ment and manipulation of the implant within the pocket is necessary to confirm its proper placement and assure appropriate redraping of the breast parenchyma over the implant ( TECH FIG 5C ). ■■ This maneuver is especially important with textured devices, as these implants are less mobile and less likely to stretch the pocket and, thus, a distortion or wrinkling of the implant in a tight pocket may be per- manent if not resolved before closure. ■■ Repeated removal and insertions of the implant should be avoided to minimize implant or incision damage, potential contamination, and pocket over- dissection. This is especially important with shaped implants, as a stretched pocket from over manipula- tion could lead to implant rotation postoperatively ( TECH FIG 5D ). Pocket Closure ■■ Before incision closure, the patient should be placed in the upright position to assess implant position, fold posi- tion, and symmetry ( TECH FIG 6A ). ■■ The inframammary approach is useful to control the fold position during the final closure.

■■ The cuff of superficial Scarpa fascia that was preserved during the initial incision is used to secure the fold dur- ing closure. ■■ If the IMF structure is stable, and was not violated or lowered during the pocket formation, reapproximation of the superficial fascia during closure is usually adequate. ■■ If the fold is mobile from inherent weakness or was dis- rupted with fold lowering, the pocket closure should include stabilization of the fold. ■■ Fold stabilization is accomplished by incorporating the deep fascia in the closure. ■■ The Scarpa fascia cuff is sutured to the deep fascia in the lower incisional edge during the closure of the IMF ( TECH FIG 6B ). ■■ Both the periareolar and inframammary incision are closed in three layers: deep fascia/parenchyma (2-0 Vicryl running), deep dermis (4-0 PDS interrupted), and subcuticular (4-0 PDS running) ( TECH FIG 6C ). ■■ Periareolar incisional closures do not stabilize the fold structure as it does with an IMF incision closure. ■■ If using a textured device, the implant must be seated at the desired position at the base of the breast pocket because it is less likely to settle in the pocket postop- eratively as can be seen with smooth breast implants ( TECH FIG 6D ).

TECH FIG 6  • A. Patient sitting upright prior to final closure to assess for symmetry and final aesthetic result. B. Fold stabiliza- tion with a 2-0 Vicryl incorporating the deep fascia in the Scarpa fascial closure.

1309

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

T E C H N I Q U E S

TECH FIG 6 (Continued) • C. Image of the final closure incor- porating superficial Scarpa fascia and deep fascia as one con- sistent layer without the presence of an incisional step off. D. Downward pressure on the implant/breast demonstrates a locked and stable IMF.

■■ Submuscular (Subpectoral) Implants Inframammary Fold Incision ■■ Although the submuscular pocket can be accessed by any incision (periareolar, inframammary, transaxillary, tran- sumbilical), the most common approach is through the inframammary incision. ■■ After determining the IMF position (either the native true fold position or the planned lowered position), a para- median line is drawn through the center of the breast and bisects the newly drawn IMF. ■■ The incision’s medial extent begins 1 cm medial to the paramedian line and extends laterally for the appropriate distance, as previously described based on the implant type (see TECH FIG 1A ). ■■ The incision is made with a no. 15 blade through the skin to the mid-dermis (see TECH FIG 1B ). ■■ Dissection is then carried out with electrocautery through the skin and subcutaneous tissue, beveling superiorly while rotating the breast off of the chest wall. ■■ Once dissection has been carried superiorly for 1 cm, the dissection is carried through the superficial fascia and toward the lateral pectoral border deep on the chest wall. ■■ The beveling preserves a small cuff of superficial fascia at the incision, which ensures that the fold is not inadver- tently lowered and also provides a cuff of fascia that will prove useful during closure (see TECH FIG 1C ). ■■ Dissection is carried down toward the chest wall while maintaining a constant upward retraction of the breast tissue, ultimately exposing the lateral edge of the pecto- ralis muscle. ■■ The upward retraction of the breast tissue is key as the suspensory ligaments of the breast will concomitantly elevate the muscle (see TECH FIG 1D ). ■■ It is imperative to not cut the muscle unless you can ele- vate the muscle off the chest wall. ■■ Inability to elevate the muscle most likely indicates that the identified muscle is actually not the pectora- lis, but rather the serratus, rectus, or an intercostal muscle. ■■ Dissection through an intercostal could lead to pen- etration of the pleural space and pneumothorax. ■■ Once the lateral border of the pectoralis is identified, the fascia is incised to expose the underlying muscle. Continued upward retraction of the breast will elevate the lateral border, allowing further dissection and place- ment of the retractor beneath the overlying pectoralis muscle.

Periareolar Incision

■■ The planned incision location is marked directly on the border of the inferior areolar and breast skin with a series of dots. The dots are used instead of a line to allow more accurate visualization of the exact areolar border. ■■ It is most important to follow the exact outline of the areolar border even if irregular as any deviation off the border in order to smooth the incision outline leads to a more visible scar. ■■ The planned incision should extend equidistance medial and lateral from the midline but not to exceed half of the circumference of the areola (see TECH FIG 2A ). ■■ With the skin placed under tension by the assistant, the incision is made precisely on the areolar border with a 15 blade through the skin to the mid-dermis. ■■ Dissection then proceeds through the deep dermis and breast parenchyma with electrocautery (see TECH FIG 2B,C ). ■■ The skin edges are retracted inferiorly and superiorly, and dissection is carried down through the parenchyma toward the pectoralis fascia. ■■ The dissection should be directed in an inferior direction to insure that the NAC is not inadvertently undermined during dissection and blood supply compromised. ■■ Dissection proceeds either directly through the breast tis- sue (transparenchymal) to the pectoralis fascia or infe- riorly under the skin (subcutaneous) until the fascia is reached at the fold. The authors prefer the transparen- chymal approach (see TECH FIG 2D ). ■■ With the subcutaneous periareolar approach (like the IMF approach), the breast elevation and pocket creation begins at the fold and proceeds superiorly in the subpec- toral pocket. ■■ The IMF is a fusion of the deep fascia attached to the pectoralis and the superficial fascia of the breast (see FIG 6 ). Take care to prevent disruption of the IMF as the breast and pectoral fascia are elevated. ■■ If creating a subpectoral dual plane pocket, dissection proceeds subcutaneously or transparenchymal down to the lateral border of the pectoralis muscle. ■■ If accessing the submuscular pocket, the lateral border of the pectoralis is identified and the fascia is incised to expose the underlying muscle. Continued upward retrac- tion of the breast will elevate the lateral border, allowing further dissection and placement of the retractor beneath the overlying pectoralis muscle

T E C H N I Q U E S 1310 Part 4 Plastic Surgery of the Breast ■■

When creating the submuscular pocket, it is impera- tive to not cut the muscle unless it can be elevated off the chest wall. ■■ Inability to elevate the muscle most likely indicates that the identified muscle is actually not the pectoralis, but rather the serratus, rectus, or an intercostal muscle. ■■ Dissection through an intercostal could lead to pen- etration of the pleural space and pneumothorax. Pocket Dissection ■■ After the subpectoral space is entered, dissection is car- ried upward centrally to the superior extent of the pocket. ■■ Dissection is then carried laterally just superficial to the pectoralis minor until the lateral border of the pocket is reached. ■■ Keep lateral dissection of the pocket to a minimum with the cautery because the breast/nipple neural supply from the lateral cutaneous nerves can be inadvertently cut. ■■ Blunt dissection of the lateral edge of the pocket decreases the chance of nerve transection. ■■ Carry the dissection inferiorly along the lateral border of the pocket, identifying and staying superficial to the serratus muscle until the inferior extent of the pocket at the IMF is reached.

■■ Avoid overdissection of your pocket laterally to facili- tate optimal medial projection of the implant. ■■ The pectoralis is then released along the planned IMF, staying 1 cm superior to the fold to account for caudal muscle descent. ■■ Dissection directly at the fold will often lead to a fold that is lower than planned as the muscle retracts inferi- orly ( TECH FIG 7A ). ■■ As the dissection is carried medially along the IMF, it is critically important to stop it at the most medial extent along the sternum ( TECH FIG 7B ). ■■ Preservation of the most caudal attachment of the pecto- ralis muscle at the transition point (TP) along the sternum is critical to minimize the chance of window shading of the pectoralis with subsequent medial implant exposure and animation deformities ( TECH FIG 7C,D ). ■■ A transition zone (TZ) of tapered muscle release con- nects the transition point to the main body of medial pectoral muscle along the sternum. ■■ The extent of the pocket is completed by defining the medial pectoral border and dividing all of the accessory slips of pectoralis muscle that insert along the ribs, pre- serving only the main body of the muscle as it inserts along the sternum.

Muscle release

TZ

TP

IMF

C

TECH FIG 7  • A. Inferior/lateral border of the pectoralis major after it was released along the IMF. B.  Inferior release of the pectoralis major heading medially toward the sternum. C. Transition zone ( TZ ) and transition point ( TP ). Dashed line reveals pectoralis muscle release medially up to the TP. Solid line represents the inframammary fold ( IMF ). D. Schematic demonstrating the release of the pectoralis off of the chest wall to the transition point ( TP ). Notice the transition zone ( TZ ) which is a zone of thinning of the muscle at the caudal end of the ster- num just medial to the TP.

TZ

TP

D

1311

Chapter 2 Breast Augmentation: Subglandular, Subfascial, and Submuscular Implant Placement

■■ Dividing these muscle slips with electrocautery instead of blunt dissection improves postoperative cleavage and maintains hemostasis. Although completely divid- ing all accessory slips is required to achieve maximal cleavage, division of the main body of medial pectora- lis muscle should be preserved, other than conservative thinning at the transition zone, to minimize the risk of postoperative wrinkling or implant show. ■■ This division of the inferior pectoralis muscle just above the IMF during initial pocket dissection creates a level 1 dual plane. Thus, all subpectoral pockets where the muscle is released inferiorly are actually dual-plane pockets, as the segment between the caudal edge of the divided muscle and the IMF is subglandular. 21 ■■ The level of dual plane required varies, and each sur- gery can be tailored to provide the optimal level based on soft tissue requirements and implant selection. ■■ The greater the amount of breast parenchyma or breast laxity, the greater the level of dual plane. ■■ It is this creation of a lower pole subglandular pocket that allows for an optimal breast-implant interface and soft tissue redraping. ■■ Failure to optimize the breast-implant interface can lead to a waterfall deformity, with the breast sliding off of the implant. ■■ When submuscular, IMF lowering can be more chal- lenging as it is tempting to carry the dissection under the muscle inferiorly to lower the fold. ■■ The dissection along the chest wall at the level of the fold is deep to the suspensory ligament structures that create the IMF. ■■ IMF lowering in the subpectoral pocket requires transi- tioning into a more superficial plane above the pectoralis fascia to lower the IMF. 20 ■■ Dissection deep to the pectoral fascia will likely result in a lowered fold with persistence of the fold structure, resulting in a double-bubble deformity. ■■ This is more likely when dissection begins from above, such as a periareolar or transaxillary approach. ■■ When using an IMF incision, the dissection below the native fold begins in the subcutaneous plane until the pectoralis muscle is reached, resulting in appropriate obliteration of the native fold at the correct level. Implant Placement ■■ The implants are bathed in the irrigation solution before insertion. Gloves are changed and rinsed with the irriga- tion solution to remove any residue (see TECH FIG 5A ). ■■ In the authors’ practice, the implant is placed into the pocket with the assistance of an insertion sleeve such as the Keller funnel (see TECH FIG 5B ). ■■ The opening of the funnel should be cut large enough to allow easy egress of the implant through the funnel. This is easily confirmed by passing the implant with irrigation solution through the funnel prior to pocket insertion.

■■ The implant orientation is then confirmed in the fun- nel, and a maneuver of squeezing the implant through the funnel with gentle pressure exerted on the back of the funnel allows the implant to slip effortlessly into the breast pocket. ■■ These maneuvers provide a “no-touch” technique, which has been associated with lower capsular con- tracture rates. 12,13 ■■ Once the implant is in the pocket (see FIG 3A ), a finger- assisted assessment and manipulation of the implant within the pocket is necessary to confirm its proper placement and ensure appropriate redraping of the breast parenchyma over the implant (see TECH FIG 5C ). ■■ This maneuver is especially important with textured devices, as these implants are less mobile and less likely to stretch the pocket and, thus, a distortion or wrinkling of the implant in a tight pocket may be per- manent if not resolved before closure. ■■ Repeated removal and insertions of the implant should be avoided to minimize implant or incision damage, potential contamination, and pocket overdissection. ■■ This approach is especially important with shaped implants, as a stretched pocket from overmanipulation could lead to implant rotation postoperatively. Pocket Closure ■■ Before incision closure, the patient should be placed in the upright position to assess implant position, fold posi- tion, and symmetry, and the adequacy of the dual plane (see TECH FIG 6A ). ■■ The IMF approach for submuscular implant placement is useful to control the fold position during the final clo- sure. The cuff of superficial Scarpa fascia that was pre- served during the initial incision is used to secure the fold during closure. ■■ If the IMF structure is stable and has not been vio- lated or lowered during the procedure, reapproxima- tion of the superficial fascia during closure is usually adequate. ■■ If the fold is mobile and unstable from either inherent weakness or from disruption during fold lowering, the pocket closure should include stabilization of the fold. ●● Fold stabilization is accomplished by incorporating the deep fascia in the closure. ●● The Scarpa fascia cuff is sutured to the deep fascia in the lower incisional edge during the closure of the IMF (see TECH FIG 6B,C ). ■■ Both the periareolar and inframammary incision are closed in three layers: deep fascia/parenchyma (2-0 Vicryl running), deep dermis (4-0 PDS interrupted), and subcuticular (4-0 PDS running). ■■ If using a textured device, the implant must be seated at the desired position at the base of the breast pocket because it is less likely to settle in the pocket postopera- tively as can be seen with smooth breast implants (see TECH FIG 6D ).

T E C H N I Q U E S

Made with FlippingBook - Online Brochure Maker