[Anatomy of the frontal region].

Abstract

The forehead is an anatomic region located between the frontal hairline cranially, the eyebrow and the glabella caudally, and the anterior border of the temporal fossa laterally on both sides. Its vertical situation, due to the telencephalon growth, is specific of the human species. From surface to deep planes, the skin and sub-cutaneous fat pads are described first. The muscular plane is constituted of the frontal muscles elevators of the forehead and the eyebrow, and the depressors which are the procerus and orbicularis oculi muscles superficially, the depressor supercilii muscle, and the corrugator supercilii in a deep plane. The galea aponeurotica, located deep to the frontal muscles, is a fibrous lamina on which the muscles of the skull insert. There is a sexual dimorphism of the frontal bone. The male forehead has extensive supraorbital bossing, and above this there is often a flat area, in teh femalethe supraorbital bossing is often nonexistent and above, there is a continous mild curvature. Blood supply to the forehead is given by an anterior pedicle constituted by the supraorbital and supratrochlear vessels and a lateral pedicle made of the anterior branches from the superficial temporal vessels. The sensory innervation of the forehead is given by the ophtalmic nerve which divides in frontal, nasociliar and lacrymal nerves. The motor innervation is given by the temporal ramus of the facial nerve which passes laterally to the zygomatic arch, and gives the innervation of the frontal, corrugator supercilii and procerus muscles.