ANATOMY OF THE POSTAURICULAR ISLAND REVOLVING-DOOR FLAP (FLIP-FLOP FLAP)

Reconstruction following resection of auricular (cavum conchae) lesion s may be done with a retroauricular rotation flap. Recently there has been revived interest in this elegant reconstructive procedure. Althou gh the vascular anatomy of the area was studied, no direct study of fl ap anatomy was reported, Six fresh adult male cadaveric dissections of the retroauricular area were performed, The skin and underlying subcu taneous tissue layer were reflected to correspond with flap size, and anatomic structures were studied. Dissection was carried out on 12 ear s. The origin of the occipital belly of the occipitofrontalis muscle a rising from the posterior mastoid region was identified in four patien ts and only as part of the fascial layer overlying the posterior masto id region, Only a small portion of the sternocleidomastoid tendon at b est is possibly incorporated in the flap, It seems that only a negligi ble contribution to the flap is derived from the temporalis muscle, Th e posterior auricular muscle was identified in all patients and its or igin from the skull was (in all patients) included or bordered the pos terior flap region. The posterior auricular artery (PAA) was seen in a ll 12 dissections. The artery was adjacent to the styloid process medi al to the parotid gland superficially between the auricular cartilage and the mastoid process, The PAA was then found on the periosteum of t he mastoid process, ascending deep to the posterior auricular muscle. The flap seems to be a truly fasciocutaneous flap with small, question able, superior and anteroinferior muscular contributions, and an inclu sion of the rather small posterior auricular muscle. As reported in ot her studies, blood supply to the area seems to be derived from the PAA .