GAP stands for gluteal artery perforator, a blood vessel that runs through your buttocks. An IGAP flap uses the inferior gluteal artery perforator blood vessel, as well as a section of skin and fat from your lower buttocks — basically the lower section of the “butt cheek,” near the buttocks crease — to reconstruct the breast. Because no muscle is used, an IGAP flap is considered a muscle-sparing type of flap.
IGAP flap surgery is less commonly done than the other type of GAP flap, the SGAP (superior gluteal artery perforator) flap or hip flap, which uses tissue from top section of the buttocks, high up on the hip.
GAP flaps tend to make the most sense for women who are having both breasts reconstructed but can’t use tissue from the abdomen — either because the abdomen is thin or has been damaged by other previous major surgeries there, such as a tummy tuck.
In the IGAP flap surgery, fat, skin, and blood vessels are cut from your lower buttocks 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. Because skin and fat are moved from the buttocks to the chest, having the IGAP flap can mean your buttocks will be smaller and tighter. However, some of the natural contour of the buttocks can be lost, which some women don’t like. The IGAP flap leaves a scar in the buttock crease, so it generally isn’t that visible.
There aren’t many surgeons who perform GAP flap surgeries. Those who do tend to prefer the SGAP/hip flap surgery, which removes tissue from high on the hip to avoid placing the surgical site in a potentially weight-bearing area, as the IGAP approach does. Also, surgically tightening the buttock is more effective when pulling more above, much like “pulling up your pants.” The IGAP is less favorable because fat is removed from the area over your ischium, the large weight-bearing bone in your pelvis. This is where you bear your weight when you are sitting. It also produces some numbness around the incision site, which may be a concern for the formation of pressure-related wounds.
IGAP flap 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. An IGAP flap may be a good choice for thin women who don't have enough extra belly tissue for a TRAM, DIEP, or SIEA flap. If you've previously had liposuction on your buttocks, you may not be a good candidate for IGAP flap 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 IGAP flap reconstruction on these pages: