To expand the indicational spectrum of the myocutaneous vastus lateralis flap, which is often too voluminous for intraoral application, we performed extreme, primary thinning of the fat and muscle component of this microsurgical transplant in 14 patients. After subfascial localization of the 0.5- to 1.0-mm-thick perforating vessel, it is exposed through the fascia and muscles up to its exit from the descending branch of the lateral circumflex femoral artery. After isolating the perforating vessel, it is no longer necessary to include parts of the vastus lateralis muscle in the flap. The fatty tissue of the remaining epifascial fat component is completely removed except for a ca. 1- to 2-cm-wide cuff of fatty tissue and fascia around the perforating vessel. When performing this primary radical removal of the subcutaneous fatty tissue, care should be taken not to injure the deep subdermal vascular plexus. In addition to the thinning procedure, de-epithelialization of the skin was performed using scalpel blade dissection (five patients) or carbon dioxide laser (6 W, five patients). This thinning technique was used for covering ten intraoral and four extraoral defects and enabled the raising of skin flaps with a thickness of 3-5 mm even in obese patients. The vessel pedicle length of thinned flaps was between 12 and 16 cm; flap size varied between 4 x 5 and 9 x 15 cm, and the donor sites were directly closed. In one case, there was a partial necrosis (20%), but the remaining flaps healed without complications. On the intraoral flaps, a thin, smooth and pliable surface developed after re-epithelialization within 3-6 weeks. The described method expands the application possibilities of the myocutaneous vastus lateralis flap for a large number of intraoral and flat defects with minimal donor-site morbidity.