Brow Deformities

Figure 6-5 Three planes of superficial temporal fascia (STF). Plane I is confluent with the deep galea plane across the zone of fixation (slanted lines). Planes II and III are thin, yet distinct fibrous sheets that rest over temporalis fascia (TF). The frontal branch of the facial nerve (FB) consistently runs just under or within plane I in the anterior temporal region. Frontalis muscle (FM) and deep (DSO) and superficial (SSO) divisions of the supraorbital nerve are indicated. Modified with permission from Knize DM: An anatomically based study of the mechanism of eyebrow ptosis.

    Changes in brow position and of the surrounding soft tissues occur with age and have a profound effect on periorbital aesthetics. The most discernible change is the development of rhytids. Prolonged hyperactivity of periorbital and forehead musculature results in the development of deep furrows perpendicular to the direction of muscle contraction. Deep horizontal furrows of the forehead are attributed to the frontalis, whereas horizontal furrows in the glabellar region are secondary to procerus hyperactivity. Vertical furrows in the glabellar region are a result of corrugator hyperactivity. Transection or resection of the offending musculature during brow lifting procedures can ameliorate these deformities and prevent dynamic accentuation of rhytids from muscle activity. Alternatively, muscle function may be targeted with botulinum toxin, but will require periodic treatments to maintain the result. Brow ptosis is typically a major component of the age-related changes affecting the periorbital region. This is characterized by malposition of the brow and migration of brow skin into the superior lid region creating skin excess, loss of the normal supratarsal definition and lateral hooding. Although the exact mechanism is not clear, several factors have been proposed for the development of brow ptosis (Fig. 6-6).5 The frontalis muscle suspends the brow and resists the tendency for ptosis. The lateral-most limit of frontalis muscle resting tone extends to the zone of fixation along the temporal fusion line. Lateral to this region, the weight of the unsupported tissue mass over the temporal fossa in association with lateral orbicularis oculi and corrugator muscle activity contribute to the descent of the lateral brow.


    Manual elevation of the lateral brow will improve the periorbital appearance of most middle-aged persons presenting for facial rejuvenation and is easily demonstrated to the patient. The difficulty lies in surgically recreating the result obtained by digital elevation of the brow during patient evaluation. Ptosis of the brow does not occur evenly across the forehead and in most cases, affects the lateral brow earlier and more markedly than the medial brow. Most surgical procedures are not able to reposition accurately the lateral brow without affecting the medial brow, especially when the medial brow depressors (corrugator) are surgically-transected.

Figure 6-6 Forces contributing to lateral eyebrow ptosis. Unsupported eyebrow lateral to the temporal fusion line of the skull (TL) is pushed down by the gravity-driven descent of the temporal fossa soft tissues. The lateral-most limit of frontalis muscle resting tone suspension of the eyebrow extends just over the zone of fixation (slanted lines) along the temporal fusion line of the skull. Hyperactive corrugator supercilii muscle and lateral orbicularis oculi muscle action can antagonize frontalis muscle action and actively facilitate the descent of the superficial temporal fossa soft tissues. Modified with permission from Knize DM: An anatomically based study of the mechanism of eyebrow ptosis.