Centre de Chirurgie Plastique de l’Île-des-Sœurs is pleased to present important information concerning mammoplasty's.
Types of implants
A - Shell: The shell of prostheses or breast implants is made from a silicone elastomer (solid silicone rubber). This material is considered to be extremely inert and is widely used for various types of medical prostheses (e.g.: joint prostheses for the hand).
B - Content: The actual content of prostheses consists of salt water or silicone gel
- Salt water or saline: Water with a salt concentration similar to that of blood. The human body is comprised of 60% to 65% water and salt. These prostheses are also referred to as inflatable, because the water is injected into the prosthesis during the operation. A valve holds the water inside the prosthesis.
- Silicone gel: Silicone gel is a silicone polymer that has a different degree of cohesivity. Silicone gel is not a natural substance in the human body, even though a minimal concentration in the blood can be considered normal.
Forming a capsule
Once the breast prosthesis has been positioned, the body forms an envelope of scar tissue around the prosthesis in order to isolate it. This envelope is called a capsule. The formation of a capsule around prosthesis is a normal part of the healing process, just as one forms around any foreign body that is implanted into the body (e.g.: a metal plate to treat a fracture).
In reaction to the prosthesis, the capsule that forms can sometimes contract, leaving less room for the prosthesis. In such cases, the prosthesis feels harder to the touch, and may distort the breast. This condition is referred to as capsular contracture. If this occurs, it may be necessary to undergo another operation (capsulotomy) to increase the space around the prosthesis, understanding that the condition may recur. The frequency of capsular contracture varies depending on the type of prostheses:
- Salt water prostheses: The frequency of capsular contracture around salt water prostheses is estimated at approximately 5%. This condition generally occurs within the first months following the surgery.
- Silicone gel prostheses: The frequency of capsular contracture around silicone gel prostheses is estimated at approximately 25%. This condition can occur within the first months following the surgery or many years later.
Service life of a prosthesis and deflation
Breast prostheses are generally implanted in young patients. They should not be considered to be life-long prostheses, even though their service life cannot be predicted.
A - Salt water prostheses: Over time, prostheses can lose some water, either through the valve or because of a leak in the shell. In such cases, the water is absorbed by the body, and deflation occurs. The prosthesis must be replaced.
When salt water prostheses were first introduced (1965), valve-related deflation was a very frequent occurrence, which limited their use. In the 1980s, despite the use of a more secure valve, deflations related to leaks in the shell were more common, often as the result of under-inflation. The risk of deflation is currently estimated a 2% to 3% within 5 years, as deflations tend to occur within the first years. There is no recommendation with respect to replacing prostheses based on their service life.
Guarantee: If deflation occurs, the manufacturer will replace the prosthesis, regardless of the date of the surgery. In addition, if deflation occurs within the first 10 years, the manufacturer often covers the costs associated with the procedure for replacing the prosthesis (operating room costs and anesthesia, as required) as well.
B - Silicone gel implants: Over time, prostheses can lose silicone, either through a rupture of the shell or by silicone passing through the shell (transudation or seepage), as the shell weakens as a result of prolonged contact with the gel. With the presence of loose silicone in the cavity, one must be aware that the silicone will be in contact with the breast and the surrounding tissue. In addition to the fact that the presence of loose silicone in the cavity increases the frequency of contraction of the fibrous capsule, it can also cause local damage to the breast, migrate into more remote tissue (ganglions) or increase the percentage of silicone in the blood. If the presence of loose silicone in the cavity is detected by mammography or by MRI, the prosthesis must be replaced. However, tests cannot detect minimal quantities of loose silicone in the cavity, which is why it is wise to plan to replace the prostheses for preventive reasons in 10-12 years, despite the current marketing claims by manufacturers, who state that the gel remains inside the prosthesis in the case of a defect in the shell, because of the cohesivity of the gel. However, it has not been proven that the gel maintains its cohesivity over the long term. On the other hand, an increased percentage of silicone in the blood has not been shown to result in health problems to date.
Guarantee: If the shell ruptures, the manufacturer will replace the prosthesis, regardless of the date of the surgery. If it occurs within the first 10 years, the manufacturer often covers the costs associated with the procedure for replacing the prosthesis (operating room costs and anesthesia, as required) as well. However, if there is loose silicone present in the cavity but no rupture of the shell of the prosthesis, the replacement policy does not apply.
Sub-mammary or sub-muscular implants
The prosthesis can be placed between the mammary tissue and the pectoral muscle (sub-mammary implant) or between the pectoral muscle and the thorax (sub-muscular or sub-pectoral implant). In my experience, sub-muscular implants feature numerous advantages:
A – More esthetically pleasing shape: The tissue covering the implant is thicker. The upper contour of the implant is hidden by the muscle and is less visible. Capsular contracture is also less frequent with sub-muscular implants:
B – Less frequent changes in the sensitivity of the nipple and the breast: Following the implant surgery, a temporary decrease in the sensitivity of the nipple and the breast for several weeks is normal. However, these changes can be permanent in 10% of cases. This frequency is considerably lower with the sub-muscular implants.
C - Better support for the prosthesis: In the case of sub-mammary implants, the prosthesis is supported by the skin alone. Over time, the weight of the prosthesis can cause the skin to stretch more quickly. In the case of sub-muscular implants, the prosthesis is supported by the muscle, and the weight of the prosthesis has less effect on the stretching of the skin.
1 - Length: With a salt water prosthesis, the required incision is 3 cm, regardless of the size of the prosthesis, because the prosthesis is empty when it is inserted. With a silicone gel prosthesis, the required incision is at least twice as long, and sometimes longer, depending on the size de the prosthesis, because the prosthesis is full when it is inserted.
2 - Location: Although the scar caused by the incision is usually difficult to see, it is sometimes more visible than expected. Therefore, the location of the incision may be important. The incision can be made in the following locations: mammary fold, armpit, nipple, navel.
a - Mammary fold: This is the most common location. The incision is hidden in a natural fold, and is easily hidden by a bra. This location allows the surgeon to create the cavity where the implant will be placed with his fingers, and affords optimal control during the procedure. In the case of a secondary procedure, the incision must often be made in this location, even if the initial incision was elsewhere.
b - Armpit: The incision is also hidden in a natural fold, but in an area that is more exposed to view than the mammary fold if the scar is visible. It is widely understood that a scar in the armpit often signifies breast enhancement surgery. In addition, the incision is far from the site of the implant, and does not allow the surgeon to create the cavity where the implant will be placed with his fingers (specialized instruments must be used). With this approach, the risk of not having the prosthesis in the ideal position are elevated, with the prosthesis being placed too far to the side, because it is inserted from the side, or with differences in location between the two breasts. In the case of a secondary procedure, it may be necessary to make the second incision in the mammary fold.
c - Nipple: The incision is hidden in the natural border of the areola, between the brown and white areas. This area, which is shaded, may present a clearer border because of the scar. If the scar pulls, this can sometimes distort the roundness of the nipple. This incision location may also increase the risk of decreased sensitivity of the nipple. However, this approach is more desirable when a procedure involving the areola is required (e.g.: reduction of an excessively large areola).
d - Navel: A 3-cm incision in the navel cannot be completely hidden. In addition, it is not hidden in a natural fold, as with the other approaches. It is harder to hide the scar under clothing, especially given current styles, which often leave the area around the navel uncovered. The incision is very far from the site of the implant, and requires sophisticated instruments that make this technique more time consuming and more difficult, especially in the case of sub-muscular implants, with no offsetting advantages. A secondary procedure cannot be carried with an incision in the same location.
Selecting the size of the implant
For someone who has never had large breasts, selecting the size of the prosthesis is difficult, due to lack of experience. During the consultation, a trial with prostheses of different volumes under a sports bra gives a good approximation of the final results, and helps the patient to make an informed decision. In my opinion, it is important to respect two principles in order to have a natural-looking breast after the implantation of prostheses:
A - Prosthesis centred with respect to the breast and the nipple: In order to avoid distorting the breast, the prosthesis must be centred with respect to the nipple and the breast, both horizontally and vertically.
B - Large enough prosthesis to ensure a minimal space between the breasts: In order to achieve a natural look, the space between the breasts should not be too large, with a more voluminous breast that begins at the centre at the level of the sternum. In addition, the diameter of the prosthesis must be large enough to maintain a minimal space between the breasts.
Final volume of breast
The final volume of the breast depends on the volume of the prosthesis and the initial volume of the breast. In general, patients prefer to increase the volume by two cup sizes. Those who currently wear an A or B cup with a significant amount of padding will wear a C cup, and those who currently wear a full B cup will wear a D cup.
Salt water or silicone gel
A - Prostheses: salt water or silicone gel
Any prosthesis, when placed in the vertical position, will have folds on the edges. These folds may be discernable by touch, and sometimes visible, depending on the thickness and firmness of the tissue that covers the implant. Silicone gel prostheses, and especially those with gel that has a higher degree of cohesivity, are said to have less folds, but not to be without folds.
Round or anatomical shape
B – Round or anatomical shape
1 - Round: Round prostheses are the most common type used for breast enhancement.
2 – Anatomical or tear drop shape: Anatomical or tear drop shaped prostheses is less full in the upper part. Because most patients want the breast to be more full on the top, this type of prosthesis is used less often for breast enhancement. The problems are different in the case of breast reconstruction after cancer. It is necessary to use a textured shell with this type of prosthesis in order to prevent it from moving.
Low, medium or high profile
C – Low, medium or high profile
If two prostheses have exactly the same volume, the larger prosthesis will have less projection, which is referred to as low profile, whereas the smaller prosthesis will have greater projection, which is referred to as high profile. Medium profile is between the two.
Salt water prostheses offer low, medium or high profiles. The profile increases as inflation increases. Because the volume is fixed, silicone gel prostheses offer low to high profiles with more increments.
Selecting the prosthesis based on the profile:
1 - Low profile: The low profile prosthesis is larger, which means that a smaller space between the breasts is possible and the upper part of the breast can be fuller. This type is more common than the higher profile, especially for those who have a thorax.
2 - High profile: The high profile prosthesis is smaller, with more projection, which means that it does not always allow for a smaller space between the breasts, unless the thorax is narrow or a much higher volume is desired.
Smooth or textured shell
D - Smooth or textured shell
1 - Smooth shell: The smooth shell is a surface that does not cling to the surrounding tissue. If secondary procedures are required, they are technically easier. The shell is thinner, so the folds of the prosthesis are harder to feel. This is the most common type.
2 - Textured shell: The textured shell is a porous surface that clings to the surrounding tissue. The capsule that forms in the case of a textured shell is less likely to contract. This type is used more often with silicone gel prostheses. However, if secondary procedures are required, they are technically more difficult. The shell is thicker, so the folds of the prosthesis are easier to feel. The objective of a textured shell is to reduce the frequency of capsular contracture and to prevent the implant from moving. The lesser frequency of capsular contracture with sub-muscular salt water implants means that the use of a textured shell is not indicated. However, the use of a textured shell is necessary with anatomical or tear drop shaped implants in order to prevent them from moving.