Enhanced projection: Adjustable Gel Implants
Hilton Becker. M.D., F.A.C.S., FRCS Boca Raton Fl. USA.
Luis A. Picard Ami jnr, m.d Facs,FRCS., PanamaCity Panama
Silicone breast implants were first used in 1962; saline implants were developed a few years later. The main goal in developing saline implants was to enable the surgeon to place the implant through a smaller incision.
The original silicone gel implants were made of a very thick gel, necessitating a large incision for insertion. A new type of silicone gel implant was later developed, containing a softer, more liquid silicone gel that could be placed through a smaller incision, similar to that of a saline-filled implant. Although the silicone gel implant had a softer, more natural feel, it was more prone to rupture; and if it did rupture, the liquid silicone was more prone to flow out of the implant, often an unpleasant sight at the time of removal. It was those silicone gel implants that fueled the silicone scare of the 1990’s.
Good to excellent results may be obtained with saline implants; however, compared to silicone gel implants, they are more likely to have cosmetic problems associated with them. Such problems include rippling and wrinkling, resulting in an abnormal shape and feel, particularly in women with very little breast tissue. Furthermore, the leakage rate of saline implants is higher than that of silicone gel implants largely due to shell failure.
Most plastic surgeons feel that silicone gel implants are the superior device. Since the silicone gel moratorium following the silicone scare of the 1990’s, saline-filled implants have been the most commonly used implants in the U.S.; however, saline-filled implants are rarely used in other countries, due to the high complication rate.
Due to the problems related to saline implants, several improvements were instituted in an attempt to decrease these complications. One approach was to texture the shell which would, theoretically, decrease the incidence of capsular contracture (hardening around the implant). It was found, however, that texturing actually led to additional rippling and a higher incidence of implant rupture. The thicker shell also made the implant more palpable.
Another advance in the area of saline implants was the introduction of adjustable saline implants. These implants offer many advantages over the standard saline-filled implant. Because the implant can be filled after surgery, the patient has input into the final size. In addition, size can be adjusted accurately in cases of breast asymmetry. Small breasts can also be expanded to improve the shape. Most importantly, rippling can be decreased by adjusting the volume of the implant post-operatively. The spectrum valve (used in adjustable saline implants) has a decreased leakage rate compared to the standard diaphragm valve.
After reviewing case studies, it also became evident that the incidence of leakage could be reduced by mildly overfilling the implant. Overfilling did not cause firmness, thus enabling the implant to function well over a wider volume range.
The adjustable saline implant is particularly useful in treating breast implant complications, such as scarring, asymmetry, and capsular contracture.
Adjustable saline implants paved the way for wide acceptance of immediate breast reconstruction. The implant can be placed under filled at the time of the mastectomy, thus greatly decreasing the risk of wound breakdown, due to excessive pressure on the raised skin flap. Once healed, the tissues can then be safely expanded. Upon completion of the expansion, the injection dome is removed, leaving the implant in position and, thus, avoiding an unnecessary two-stage procedure.
Volume adjustability of adjustable saline implants also makes them safer to use in cases where radiation will or has been used.
While saline implants continue to be improved, improvements are also being made with silicone gel implants. One of these improvements is the increased viscosity of the gel. The new “5th generation” or cohesive gel implant has been shown to have a far lower incidence of rupture. Also, if, for some reason, the shell does rupture, the gel remains cohesive and in its original form.
Texturing was also applied to gel implants in order to decrease the incidence of capsular contracture. A consensus of opinion remains as to the advantages and disadvantages of texturing. Textured implants are more difficult to insert and position. The introduction of anatomical, or shaped, implants was a further innovation. Texturing is necessary in these implants in order to prevent rotation.
Newer anatomical implants have been developed with enhanced projection ability. The first attempt at an enhanced projection implant consisted of a double-lumen device with a more dense gel in the inner lumen. Although excellent results were initially obtained, a high incidence of rupture occurred where the two shells were joined. The heavier gel, having a different viscose-elastic property to the surrounding gel, caused unanticipated shearing forces, which resulted in eventual rupture. An improved version of this enhanced projection implant, having two different gels within the same shell, has shown encouraging results.
Double-Lumen Adjustable Implants
In order to combine the advantages of saline implants with the advantages of the gel implants, double-lumen adjustable implants were introduced. These implants function in a similar way to adjustable saline implants with the added advantage of having silicone in the outer chamber consisting , resulting in a better look and feel.
The currently available adjustable double-lumen implant has either 25% or 50% gel in the outer chamber, and they are known as the 25/75 or the 50/50, respectively.
Texturing was also added to the adjustable double lumen implants; however, the thicker shell necessitated by the textured surface decreased the elastic properties, rendering the device less effective as a tissue expander.
The anatomical textured adjustable gel saline implant has been used outside of the United States, but is currently still not FDA-approved in the U.S.A.
Enhanced Projection: Adjustable Gel Implant
In choosing a breast implant today, it is no longer simply a matter of volume. The surgeon must consider a wide variety of measurements and factors, including:
Adjustable implants have been proven very effective in managing these discrepancies. Today, however, adjustable implants are more like saline implants, with a coating of silicone. Subareolar projection is often deficient. Therefore, a new generation implant has been developed to address these deficiencies.
The implant is essentially a gel implant, with a centrally placed small inner lumen, to which saline can be added, as desired. Should no further projection be desired, the saline chamber can be left completely empty. The degree of enhanced projection can be determined with the implant in position. Alternatively, the fill tube can be attached to an injection dome and buried or exteriorized.
The inner chamber is filled, preferably to a point to where it becomes taut. Projection is greatly enhanced, without firmness, due to the cushioning affect of the surrounding gel. Another advantage of the small inner lumen is that the volume of the implant can be increased without altering the base diameter (i.e., with a specific base diameter, the volume and projection can be selected by the surgeon and modified by the patient post-operatively).
The adjustable gel implant known as the” Spectra” has recently been introduced in Europe, with both a smooth and textured surface. The anatomical version will be released later this year.
The adjustable gel implant decreases the need for the vast array of shapes and sizes that a surgeon must select from, when using fixed volume anatomical implants.
Post-operative adjustability will be most beneficial in cases of asymmetry, and patients desiring enhanced projection.
Figure 1a: Saline added post operatively via injection dome injection; dome may be removed at any stage
Figure 1b: Filled to enhance projection, fill tube removed
Figure 1c: Implant in position, no saline added. Saline may be added on the operating table, or post operatively
Figure 2a: Patient undergoing Augmentation mastopexy with a the Spectra implant
Figure 2b: Volume adjusted prior to fill tube removal
Figure3a: Pre Op
Figure 3b: Post augmentation mastopexy with Spectra implant
Figure 3c: Pre op lateral
Figure 3d: Post op lateral figure
Figure 4 a: Patient following previous augmentation mastopexy Saline implants 225cc
Figure 4 b: Following circumareolar mastopexy and replacement with 275 cc spectra filled to 285 cc on the R and 305cc on the L
Figure 4 c: Pre Op Lateral view Img3345
Figure 4d: Post Op lateral view