SURGICAL BREAST ENLARGEMENT TECHNIQUES
The general principles of breast augmentation surgery need to be observed even more stringently when the use of prosthetic material such as implants is involved. Once appropriately informed and consented to by the surgeon, the most basic operative technique decisions involve choices in:
- Access Incision
- Pocket Creation
Use of sterile technique, no-touch approach and perioperative antibiotics are naturally vital.
- Infra-mammary (Under the breast) by far, this is the most common and versatile access incision. It is the most versatile incision allowing most clear dissection, subsequent visualisation of the implant pocket and placement of the implants in any pocket. The evidence also suggests that it is least associated with capsular contractures. This maybe due to clear visualisation and “dry” technique allowing good haemostasis or reduced risk of bacterial contamination through the incision and operative field. Its direct access to the glandular-muscular interface and overlap allows manipulation of either or both for the best symmetrical and aesthetically pleasing outcome. The drawbacks of this access are the relative visibility of the scar, its site and placement. The incision should be placed in the predicted location of the new IMF, which has been determined and marked preoperatively. An incision length of up to 5.0 cm is required. The incision should be designed with the majority of the incision lateral to the breast midline, as this will place the resulting scar in the deepest portion of the new IMF.
- The periareolar approach for augmentation mammaplasty was described by Jenny in 1972. The principle advantage of this incision is that the resulting scar is usually well-camouflaged and quite inconspicuous. The periareolar approach allows easy adjustment of the IMF and direct access to the parenchyma for scoring and release when the lower pole of the breast is constricted. Whether this is a transparenchymal approach or peri-parnchymal via dissection to the inferior pole this incision allows for access for creation of sub-glandular, sub-muscular as well as subfascial pockets. In addition to the higher risk of contamination and apparent association with higher capsular contracture rates, it is associated with reduced sensitivity and of the Nipple Areolar Complex (NAC) as well as increased rates of peri-areolar pain. The dissenting view has been offered by a much smaller series of 20 patients not showing any difference between the two incision types. In pigmented skin the risk of keloid and depigmentation remains high. It is also exceedingly difficult to place many cohesive or anatomically shaped implants through this incision. Despite, the evidence this access continues to enjoy popularity with many surgeons who argue for its use given the “direct” access, “remote” control of the IMF and “invisible” incision. In the opinion of the authors in light of the basic science and clinical series evidence there is no justification in using the peri-areolar incision.
- Trans-Axillary Incision: This incision technique was first developed in the 1970s as an open technique, before being adapted to a minimally invasive approach. Although this technique theoretically offers access to creation of all three implant pockets, the traditional open technique involved blunt dissection of the inferior origins of the Pectoralis Major muscle, for creation of the sub-muscular pocket. The open blunt technique led to a series of suboptimal aesthetic outcomes. This was in part due to uneven coverage of the implant, its malposition owing to in particular a lack of controlled dissection of the vascular infero-medial aspect of pectoralis major. This is also where major intercostal vessels traverse the space increasing the risk of haematomas. As saline implants became popular, especially in the United States, proponents of this technique increased. Introduction of saline implants through a 2-3 cm incision, enhanced by precision view owing to endoscopic assistance became a major standard. Currently, the technique is performed with a slightly longer incision of 4-5 cm for use of silicone implants. Although textured implants can be placed via this incision, anatomical-shaped implants cannot routinely be placed via this access incision. The IMF is lowered 1-2cm depending on size and asymmetry through this technique. The proponents of this technique point to its track record in safety, its minimal incision hidden in the axilla and remote access and better control of the IMF. With the exception of the evidence of implicating this incision in increased capsular contractures, the authors believe that this technique is more anatomically and surgically sound than the peri-areolar technique but less versatile than the infra-mammary incision. However, the purported control over the IMF is, in the opinion of the authors, offset by the fact that there is little or no possibility for a nuanced manipulation of the gland-muscle interface or position at the IMF. This is imperative in view of the authors, as it gives a more direct control on the NAC to IMF distance as well as the shape of the lower pole. Despite this fact, Tebbets reports excellent equivalent outcomes with both techniques dual plane and trans-axillary with long-term follow-up.
- Trans-Umbilical: This technique was developed in the 1990s. The first large series reported by Dowden argued for its use based on the following reasons: versatility (Access to both sub-pectoral, as well as sub-glandular pockets), minimal scarring and no implant tension on wound, reduced loss of nipple sensation, elimination of dead space and finally good control of the implant pocket. This technique is only suited to inflatable saline implants. It involves blunt dissection over the rectus sheath toward the breast. Creation of the sub-glandular or sub-pectoral pockets achieved by means of avulsion of the tissues including the inferior pectoralis major (for the sub-pectoral pocket). Despite purported good results by Dowden and other surgeons, the authors feel this is not a surgically sound technique. It has poor to no visualisation of the operative field, which defines surgery and its planned accuracy. It only has application for inflatable saline implants. Its safety based on basic surgical principles cannot be recommended in comparison to any of the other incisions.
Pocket Creation for Implant
- Sub-glandular (under the breast over the muscle): The original implant pockets were dissected in a sub-glandular plane. Where soft tissue envelope is considered thick enough, many surgeons continue to use sub-glandular pocket for implant placement.
- Sub-muscular: This approach is developed in either a complete or partial sub-muscular pockets. The lower edge of the pectoralis major is dissected off the chest wall and the lower sternum. For a total sub-muscular pocket, it may be necessary to also dissect serratus anterior and the external oblique off the chest well. The issues of animation of the implants with contraction, the implants riding too high and the wide cleavage are well-known drawbacks of the sub-muscular plane. By definition, with this technique it can sometimes be difficult to place the NAC on the most projected part of the breast tissue. Tebbet’s described the dual plane technique as a means of addressing the various shortcomings of each technique and allowing a nuanced approach to implant placement and pocket dissection. He described the dissection of tissue in both sub-muscular and sub-glandular planes. The lower edge of the pectoralis major is dissected in all cases, followed by dissection of the breast tissue from the underlying pectoralis major. He described three different levels of dissection of the breast tissue-muscle interface and redraping of the pectoralis major muscle on the implant as projected nipple level.
- Type I No dissection, the inferior border of the muscle covers the implant and entire Nipple level.
- Type II The inferior border of the muscle drapes over the implant to the level of the Nipple.
- Type III The inferior border of the muscle retracts to the superior margin of the Nipple.
I believe that the appropriate utilisation of dual plane technique provides the most flexible and nuanced approach for implant positioning and placement. It goes a long way to alleviating the implant animation problem due to muscle contraction. It allows a good soft tissue coverage of the upper pole and facilitates not only the expansion of the lower pole but eases adjustment of the IMF should that be necessary. Additionally, this technique has been shown to reduce capsular contracture rates.
3. Sub-fascial: This is a more recent technique where the implant is placed under the pectoralis major facia. They have reported very low or no capsular contractures in patients undergoing this technique. The authors have little experience with this technique. However, to observe that the pectoralis major fascia is rather thin and, indeed may not alleviate the issues of implant animation or optimal Nipple position on the breast mound.
After irrigating the pockets with betadine and antibiotics and trailing the appropriate sizers, I place the implants into the pocket and close the wound in layers with absorbable sutures covered with skin glue. This allows my patients to shower from the next morning. The surgical postoperative bra is then placed on the patient prior to transfer to recovery from the augmentation procedure.