Stacked/"Hybrid" GAP flap reconstruction is a newer approach to GAP that can be used to reconstruct one breast in women who don’t have a lot of extra tissue in their buttocks and therefore aren’t eligible for standard GAP flap surgery.
GAP stands for the gluteal artery perforator, a blood vessel that runs through your buttocks. An SGAP flap (superior gluteal artery perforator), or gluteal perforator hip flap, uses this blood vessel, as well as a section of skin and fat from your upper buttocks/hip (the so-called “love handles”) to reconstruct the breast. Because no muscle is used, an SGAP flap is considered a muscle-sparing type of flap. There is another type of GAP flap, the IGAP (inferior gluteal artery perforator) flap, which uses tissue from the bottom of your buttocks, near the buttock crease.
Your plastic surgeon may recommend GAP flap reconstruction if you don’t have enough belly tissue to reconstruct your breasts, you’ve had multiple abdominal surgeries, or you’ve had previous reconstruction that already used tissue from your belly. If your buttocks are fairly small and your breasts are larger, there may not be enough tissue to reconstruct both breasts using GAP flap reconstruction. However, if you only need one breast reconstructed, stacked GAP reconstruction may be a solution for you. This approach typically uses the SGAP flaps, also called hip flaps, from the upper buttocks.
In standard SGAP or hip flap surgery, a flap of fat, skin, and blood vessels is cut from each side of your upper buttocks/hip and moved up to your chest to rebuild your breasts. Your surgeon carefully reattaches the blood vessels of the flap to blood vessels in your chest using microsurgery. In stacked GAP flap surgery, the surgeon takes a flap of skin from each upper buttock and stacks them, one on top of the other, to recreate a single breast. Because skin and fat are moved from the buttocks to the chest, having the SGAP flap can mean your buttocks will be tighter -- as if you had a buttock lift. The SGAP flap leaves a scar near the top of your buttocks, but it's almost always covered by a bikini bottom or underwear.
Like the standard SGAP/hip flap surgery, stacked GAP surgery is more technically difficult than a TRAM, DIEP, or SIEA flap and usually takes more time to do. There are not many plastic surgeons who are trained to do it, so you may have to search for one if you’re interested in this procedure. If you've previously had liposuction on your buttocks, you may not be a good candidate for stacked GAP reconstruction because you may not have enough extra tissue available. You can consult with your surgeon about your individual situation to determine whether or not you have enough tissue.
Learn more about stacked GAP reconstruction on these pages: