BREAST AUGMENTATION

Definition: 

Breast augmentation, also known as breast enlargement, mammoplasty enlargement, augmentation mammoplasty, and popularly known as boob job, is a surgery performed to increase the size of the breasts in women that are dissatisfied with the size of their breasts for either cosmetic or reconstructive reasons (e.g. after treatment for breast cancer or to correct congenital deformities and asymmetries). According to the American Society of Plastic Surgeons, breast augmentation is the most commonly performed cosmetic surgical procedure in the United States.

Indications:

Primary augmentation (for cosmetic reasons)

Primary reconstruction (in cases of congenital deformities (presents at birth), trauma, or after treatment for breast cancer)

Secondary augmentation (revision surgery to correct or improve the aspect of the breasts)

Procedure:

The surgical procedure for breast augmentation takes approximately one to two hours. Variations in the procedure include the incision type, implant material, and implant pocket placement, as follows:

A)     Incision types:

• Inframammary: an incision is placed below the breast in the infra-mammary fold (the place where the breast and the chest meet). This approach provides maximum access for pocket dissection and placement of an implant. However, this method can leave more visible or thicker scars. 

•  Periareolar: an incision is placed along the areolar border (usually the lower half). This technique allows the surgeon to make adjustments to the infra-mammary fold position or even to combine a mastopexy (breast lift) with it (e.g. Benelli mastopexy). Silicone gel implants require a minimal incision length of about 4 -5 cm, which could be contraindicated in patients with small areolas. This method can also leave visible or thicker scars, especially if the surgeon fails to accurately follow the border of the areola. The quality of the scars is better in patients with lighter areolar pigment. This technique is more associated with breastfeeding problems, due to cutting milk ducts, and problems with areolar sensitivity.

• Transaxillary: an incision is placed in the armpit and the dissection tunnels medially. This approach allows implants to be placed with no visible scars on the breast, but is more likely to produce asymmetry of infra-mammary fold (the bottom of the breasts). Subsequent revisions of transaxillary-placed implants usually require inframammary or periareolar incisions. Transaxillary procedures can be performed with or without an endoscope, which is small video camera that allows the surgeons to perform the surgery under direct vision, increasing the precision of the procedure.

• Transumbilical Breast Augmentation (TUBA): a small incision (~ 2 cm) is placed in the navel and dissection tunnels superiorly. This approach enables implants to be placed with no visible scars on the breast, but makes appropriate dissection and implant placement more difficult. Transumbilical procedures can also be endoscope-assisted or not. This technique is not appropriate for placing silicone gel implants because those implants are pre-filled and cannot be passed through the small 2-cm incision.
• Transabdominoplasty Breast Augmentation (TABA): surgery similar to TUBA, where the implants are tunneled up from the abdomen into bluntly dissected pockets while a patient is simultaneously undergoing an abdominoplasty (tummy tuck) procedure.

A)     Implant Pocket Placement:

The placement of implants is described in relation to the pectoralis major muscle (main muscle situated at the chest, behind the mammary gland/breast):

• Subglandular: the implant is placed between the breast tissue and the pectoralis major muscle. The subglandular position in patients with thin soft-tissue coverage and small mammary gland is more likely to show ripples or wrinkles of the underlying implant. Also, the borders of the implant may be more noticeable to the eye due to insufficient soft-tissue coverage. Capsular contracture rates (see complications) are slightly higher with this approach. A rough estimate to determine if you are a candidate for this procedure is to pinch the breast tissue between your thumb and the forefinger and measure its thickness. If your breast tissue is equal to or greater than 2 cm thick, you are a good candidate for the subglandular approach. 

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• Subfascial: the implant is placed in the subglandular position, but underneath the fascia of the pectoralis muscle (which is a thin tissue layer that surrounds the muscle). The benefits of this technique are controversial, but proponents believe the fascial layer of tissue may help with coverage and sustaining positioning of the implant.
• Submuscular/Subpectoral: the implant is placed below the pectoralis without release of the inferior origin of the muscle. This technique is most commonly used for maximal coverage of implants used in breast reconstruction. The implants tend to migrate upwardly due to the contraction of the muscle.
• Submuscular/Subpectoral with Dual Plane Technique: the implant is placed underneath the pectoralis major muscle after releasing the inferior muscular attachments. It’s a combination of the subglandular technique and the submuscular technique, where the implant will be partially beneath the pectoralis major muscle in the upper pole, while the lower half of the implant is in the subglandular plane. Animation or movement of the implants in the sub pectoral plane can be excessive to some patients. The implants can also migrate upwardly if the inferior muscular attachments are not completely released.
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B)      Types of Implants (filling):

• Saline-filled Breast Implants: are made of a silicone elastomer (rubber) shell. They are inserted empty and then filled with salt water (saline) after the implant is placed in the body. Therefore, they can be surgically placed via smaller incisions (when compared to the pre-filled silicone gel implants). The saline implants may be placed through all 4 incisions available, including the transumbilical (through the belly button) approach (TUBA). Saline-filled implants are rarely used in other countries due to the increased risk of cosmetic problems when compared to silicone gel implants, such as rippling, wrinkling, and to be more noticeable.

• Silicone gel-filled Breast Implants: also made of a silicone elastomer (rubber) shell, but they are pre-filled with silicone gel. The high cohesive gel filler (that reduces the risk of leakage) associated with the high quality shell produced nowadays improved durability of the implants to the point that surgeons cannot predict a timeframe for the implants to be replaced. Capsular contracture is the most common cause of removal and replacement of both silicone and saline implants.

C)      Types of Implants (Coating):

• Smooth: the silicone rubber shell is made with a shiny polished surface.

• Textured Surface: the silicone rubber shell is made with a finely rough surface. It’s not an extra layer attached to the surface, but the surface itself is made textured rather than smooth. There are different textures depending on the manufacturer and type of implant. Overall, the purpose of texturing an implant is to prevent the rotation of the implant (in anatomical shaped implants) and to decrease the capsular contracture rates (which have been controversial). When there is rippling or wrinkling, it is more pronounced with textured than smooth.

• Polyurethane: These implants are similar to textured implants but they have an extra layer of polyurethane coating on the implant shell, which is believed to diminish capsular contracture rates. They were briefly discontinued due to concern of potential carcinogenic (related to cancer) breakdown products from the polyurethane. Polyurethane implants are still used in Europe and South America, especially in Brazil. They are surgically harder to be placed as they require more precision in its positioning and a pocket dissection. They are also more likely to present rippling and wrinkling than smooth implants.

D)     Types of Implants (Shape)

• Round: they are shaped as their name suggests. Some people think that round implants take the natural shape of the breast when held vertically into position in the body. Round implants are more popular than anatomical ones among plastic surgeons, especially in the United States and Brazil.
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• Anatomical (tear-shaped, teardrop, contour implants):  they are tear-shaped, designed to look more natural by resembling the shape of a normal breast (more volume on the bottom and less volume on the upper pole). There is risk of malpositioning or rotation, rendering the implant upside down or sideways in the body, leading to an unnatural look and a poor result. To prevent this complication, the surgeon usually uses a textured and more adherent implant. The anatomical implants were originally developed for breast reconstructive patients. There are some surgeons that prefer anatomical shaped implants to round ones (e.g. Dr Perin, Sao Paulo, Brazil, Dr. Parsa, Honolulu, Hawaii).
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E)      Types of Implants (Profile/Projection)

The profile is the relation between the projection (height) and the base diameter of an implant. The profile will depend on the patient’s frame (wide, narrow), size of the implant, and the amount of projection and cleavage desired. By comparing the patient’s frame and desires with the implants’ specifications, the surgeon is able to choose the right profile for each patient.  
 
            Low                       Moderate                       High

• Low Profile: for wide framed patients;

• Moderate Profile: Low and moderate profile implants are better used in wide framed patients

• Moderate Plus Profile: Mentor's breast implant line (both saline and silicone breast implants) also includes this profile which is between moderate and high profile breast implants.

• High Profile: if a woman has a small chest diameter, the increased breast implant width is transmitted laterally toward the arm and vertically toward the neck. This may not look and feel proportional to her body. Therefore, A high profile implant would look more natural in narrowed frame patients.

• Extra High Profile: High and extra high profile implants are used in patients with narrow and very narrow frame, respectively.

Risks: (not common but possible)

1.      Capsular contraction:  Scar tissue forms around the implant to form a hard
shell.  There are several steps to prevent it, such as, size and location of the implant, as well as medications like Singular and Acculent.
2.      Infection or rejection from non-sterile techniques.
3.      Shifting (moving) of the implant.  The pocket for the implant should be adjusted for the patient (this will usually, prevent shifting).
4.      Scars:  Less conspicuous in the periareola compared to sub-mammary incision.
5.      Sensation:  May be initially decreased.  Usually 90% of sensation will return within 1-2 years of surgery.
6.      Violation of breast tissue.
7.      Breast Feeding:  About 50% of women won’t be able to successfully breast feed, particularly those with periareola incision.
8.      Synechia:  Adhesions (also known as "kissing Breast"), sometimes related to techniques.

References:
1. Young VL, et al. (1994). "The efficacy of breast augmentation: breast size increase, patient satisfaction, and psychological effects". Plast Reconstr Surg. 94 (Dec): 958–69. 
2. National Plastic Surgery Procedural Statistics, 2006. Arlington Heights, III, American Society of Plastic Surgeons, 2007
3. Johnson GW, Christ JE. (1993). "The endoscopic breast augmentation: the transumbilical insertion of saline-filled breast implants". Plast Reconstr Surg. 92 (5): 801–8.
4. Hester TR Jr, Tebbetts JB, Maxwell GP (2001). "The polyurethane-covered mammary prosthesis: facts and fiction (II): a look back and a "peek" ahead". Clin Plast Surg 28 (3): 579–86. 
5. Heden P, Jernbeck J, Hober M (2001). "Breast augmentation with anatomical cohesive gel implants: the world's largest current experience". Clin Plast Surg 28 (3): 531–52. 
6. Tebbetts T (2002). "A system for breast implant selection based on patient tissue characteristics and implant-soft tissue dynamics". Plast Recon Surg 109 (4): 1396–409. 
7. Brown MH, Shenker R, Silver SA (2005). "Cohesive silicone gel breast implants in aesthetic and reconstructive breast surgery". Plast Reconstr Surg 116 (3): 768–79; discussion 780–1. 
8. http://en.wikipedia.org/wiki/Breast_implant
9. Tebbetts JB (2004). "Does fascia provide additional, meaningful coverage over a breast implant?". Plast Recon Surg 113 (2): 777–9.  

10. http://en.wikipedia.org/wiki/Endoscope

11. http://www.plasticsurgery.org/ 

12. Plastic surgeon's opinions around the US and Brazil 
13. http://www.locateadoc.com/articles/plastic-surgery-breast-implants-1311.html