Acellular Dermis (ACD)
Achieving an ideal breast shape, size, and feel can be difficult or impossible using a patient’s own tissues and implants alone. This is especially true in slender women or in women that have developed problems after an initial breast augmentation surgery. The patient’s own tissues may not be plentiful or strong enough to counteract the forces of muscle contraction and weight of the breast implants. So, it is exciting to have a material that can make up for a patient’s own deficiencies and help her achieve the ideal she is seeking.
A structural material has been used for many years in women needing breast reconstruction after surgery for breast cancer. This material is the thick part of human skin specially treated to remove the cells that cause allergic reactions or rejection. This process leaves a thick and soft but strong and slightly flexible sheet of collagen matrix that can be used to supplement a patient’s own tissue. After this material is stitched in place, minute blood vessels grow into the material incorporating it, making it like the patient’s own tissue. This material is called Acellular Dermis (ACD). Acellular because the cells have been removed and Dermis for the thick structural part of the skin that footballs and belts are made of. Another name for this material is Acellular Dermal Matrix (ADM). Several manufacturers make this material.
However, there are some ethical considerations of this material preventing widespread use for cosmetic patients. This material was derived from human skin donated by those wishing to help others after death by donating body organs (including skin). So, the ethical dilemma is of well-meaning donors having parts sold for cosmetic use being very different from the donor’s original intentions!
The original material mentioned above is AlloDerm® Regenerative Tissue Matrix (human origin) by LifeCell™. However, LifeCell™ has made another product called Strattice™ Reconstructive Tissue Matrix, which is derived from pig skin that resolves this ethical dilemma. Other companies’ offerings include FlexHD® STRUCTURAL Acellular Hydrated Dermis (human derived) by Ethicon, FlexHD® Acellular Hydrated Dermis (human derived) by Mentor®, and NeoForm™ (human derived) by Mentor®. My preferred material is Strattice™ Reconstructive Tissue Matrix since its introduction in 2008. Non dermal materials are also becoming available that can provide similar benefit. The first of these is SERI® Surgical Scaffold made from silk fibers.
ACD can be used to minimize recurrent capsular contracture and to transfer deforming forces, and it can be used as another layer of tissue thickness. The material itself is pricey (about twice the cost of gel implants) and takes extra time to use during surgery, making it too expensive to use during the initial breast augmentation to avoid future problems.
Revision surgery procedures often incorporate the use of ACD, which dramatically increases the odds of successful revision surgery. The decision to add the expense and complexity of using ACD depends on such factors as implant size relative to the quality of the patient’s own tissues and her willingness to risk further surgery for reoccurrence if ACD is not used.
Capsular Contracture and ACD
The thick contracting capsule does not seem to grow on Strattice™. Thus, the ACD serves as an interruption, a “firebreak” in the otherwise confluent layer of the capsule that shrinks (contracts), causing problems associated with capsular contraction. Often, capsular contraction with resultant excess implant firmness and distortions causing asymmetry causes patients to seek implant revision surgery. In the past, even with the extensive surgery complete capsulectomy and implant change, there was up to a 33 percent (one in three) chance of the firmness returning. Although only in routine use for contracture since 2008, using Strattice™ ACD seems to reduce this reoccurrence rate to about 2 percent (one in fifty).
Bottoming out, “Double Bubble”, other implant malposition and ACD
Implant malposition often involves the implant cavity being too large for the implant, allowing it to move to an undesired location and look unnatural or asymmetrical. Capsulorrhaphy and neo-pocket creation are successful at correcting many implant malposition problems. Capsulorrhaphy involves using the capsule (every patient’s body makes a capsule around the implant) to keep the implant in a better position. Often, the capsule on the other side is loosened to allow the implant to stay in the desired location. Neo-pocket creation lifts the existing capsule to place the implant in a new (“neo”) pocket to keep it in the desired location.
ACD can be used to reinforce such capsular work, making it less likely to stretch out again. Factors such as implant size relative to the quality of the patient’s own tissues and her willingness to risk further surgery if no ACD is used are considered in the decision to undergo revision surgery expense and complexity of using ACD.
Animation Deformities (excessive animation) and ACD
A woman’s breasts move as she moves, and this motion can be more noticeable after implant surgery because the breasts are larger! If implants are placed under the muscle, necessitating some muscle release, the muscle can attach to the breast tissue, skin, or scar tissue, causing pulling and indentations on the undersurface of the breast or hasten implant malposition. ACD can be used to transfer the muscle pull back to its original attachment to the ribs, reducing unwanted excessive animation.
Wrinkling, Indentations, and Other Implant Visibility Issues and ACD
ACD can be used as an extra layer of tissue between the implant and the patient’s skin and thus help hide the underlying implant. Switching from saline-filled to gel-filled “gummy bear” implants and placing subglandular implants into a sub-muscle location can reduce implant palpability. In slender patients or other situations, there is concern about support for a relatively large implant. ACD is a powerful addition to reduce implant visibility and palpability.
Surgery and ACD
The decision of whether or not ACD will be used during surgery is invariably made ahead of time.
The material comes in various shapes and sizes and is measured and ordered to best match each patient’s specific need.
The length of the operation is longer to allow time for the ACD to be prepared, custom trimmed for fit, inserted, and secured in place. Often, a sizer implant is inserted and removed repeatedly as the surgery proceeds to achieve the desired contour.
Existing incisions alone are most commonly used for the breast revision with ACD. Occasionally, a lengthened incision (or, rarely, two separate incisions) are needed. Axillary and umbilical incisions are too remote to be used for procedures involving ACD.
Most of the time the sutures (stitches) used to keep ACD in place are absorbable (removed by the body afterwards) as the patient’s own body grows into the ACD, keeping it in place soon after surgery.