Perforator flaps

Perforator flap surgery is a technique used in reconstructive surgery where skin and/or subcutaneous fat are removed from a distant or adjacent part of the body to reconstruct the excised part. The vessels that supply blood to the flap are isolated perforator(s) derived from a deep vascular system through the underlying muscle or intermuscular septa. Some perforators can have a mixed septal and intramuscular course before reaching the skin. The name of the particular flap is retrieved from its perforator and not from the underlying muscle. If there is a potential to harvest multiple perforator flaps from one vessel, the name of each flap is based on its anatomical region or muscle. For example, a perforator that only traverses through the septum to supply the underlying skin is called a septal perforator. Whereas a flap that is vascularised by a perforator traversing only through muscle to supply the underlying skin is called a muscle perforator. According to the distinct origin of their vascular supply, perforators can be classified into direct and indirect perforators. Direct perforators only pierce the deep fascia, they don't traverse any other structural tissue. Indirect perforators first run through other structures before piercing the deep fascia. Perforator flap surgery is a technique used in reconstructive surgery where skin and/or subcutaneous fat are removed from a distant or adjacent part of the body to reconstruct the excised part. The vessels that supply blood to the flap are isolated perforator(s) derived from a deep vascular system through the underlying muscle or intermuscular septa. Some perforators can have a mixed septal and intramuscular course before reaching the skin. The name of the particular flap is retrieved from its perforator and not from the underlying muscle. If there is a potential to harvest multiple perforator flaps from one vessel, the name of each flap is based on its anatomical region or muscle. For example, a perforator that only traverses through the septum to supply the underlying skin is called a septal perforator. Whereas a flap that is vascularised by a perforator traversing only through muscle to supply the underlying skin is called a muscle perforator. According to the distinct origin of their vascular supply, perforators can be classified into direct and indirect perforators. Direct perforators only pierce the deep fascia, they don't traverse any other structural tissue. Indirect perforators first run through other structures before piercing the deep fascia. Soft tissue defects due to trauma or after tumor extirpation are important medical and cosmetic topics. Therefore, reconstructive surgeons have developed a variety of surgical techniques to conceal the soft tissue defects by using tissue transfers, better known as flaps. In the course of time these flaps have rapidly evolved from 'random-pattern flaps with an unknown blood supply, through axial-pattern flaps with a known blood supply to muscle and musculocutaneous perforator flaps' for the sole purpose of optimal reconstruction with minimum donor-site morbidity.Koshima and Soeda were the first to use the name “perforator flaps” in 1989 and since then perforator flaps have become more popular in reconstructive microsurgery. Thus perforator flaps, using autologous tissue with preservation of fascia, muscle and nerve represent the future of flaps. The most frequently used perforator flaps nowadays are the deep inferior epigastric perforator flap (DIEP flap), and both the superior and inferior gluteal (SGAP/ IGAP) flap, all three mainly used for breast reconstruction; the lateral circumflex femoral artery perforator (LCFAP) flap (previously named anterolateral thigh or ALT flap) and the thoracodorsal artery perforator (TAP) flap, mainly for the extremities and the head and neck region as a free flap and for breast and thoracic wall reconstruction as a pedicled perforator flap. Perforator flaps can be classified in many different ways. Regarding the distinct origin of their blood supply and the structures they cross before they pierce the deep fascia, perforators can either be direct perforators or indirect perforators. We will discuss this classification based on the perforators' anatomy below. Direct cutaneous perforators only perforate the deep fascia, they do not traverse any other structural tissue. It is questionable whether these perforators are true perforators, because it might be more logical to not include these perforators. The surgical approach needed for direct perforators is slightly different from the one needed for indirect perforators. When direct perforators are not included, surgeons can focus on the anatomy of the perforator and the source vessel. Indirect cutaneous perforators traverse other structures before going through the deep fascia. These other structures are deeper tissues, and consist of mainly muscle, septum or epimysium. According to the clinical relevance, two types of indirect cutaneous perforators need to be distinguished. We will clarify these two types below. Musculocutaneous perforators supply the overlying skin by traversing through muscle before they pierce the deep fascia. A perforator which traverses muscle before piercing the deep fascia can do that either transmuscular or transepimysial. This latter subdivision is however not taken into account during the dissection of the perforator. Only the size, position, and course of the perforator vessel are considered then. When a flaps’ blood supply depends on a muscle perforator, this flap is called a muscle perforator flap.