EYELID RECONSTRUCTION James F Thornton MD and Jeffrey M Kenkel MD ANATOMY AND PHYSIOLOGY laterally. Its vascular supply is primarily via the oph- Surgery of the eyelids requires a thorough knowl- thalmic artery. The marginal artery of the eyelid courses approximately 3–3.5mm above the lid mar- edge of the periorbital anatomy. The complexity of 2 the eyelids as well as the importance of each com- gin. The inferior marginal arcade is supplied predomi- ponent to the function of the eyelid must be appre- nantly from branches of the facial artery in addition ciated. A detailed description of eyelid anatomy to a branch from the superior marginal vessel. These and the lacrimal apparatus was given by Jones1 in arcades travel just anterior to the tarsus. The mar- 1961. The reader is also encouraged to peruse ginal artery courses 1mm superior and anterior to Zide and Jelks’s2 Surgical Anatomy of the Orbit for the base of the lower tarsus.3,4 Laterally the superfi- a complete description and excellent illustrations of cial network of the skin is supplied primarily by the periorbital anatomy. branches of the superficial temporal artery and the lacrimal artery. Blood Supply The extensive collateralization that exists between branches of the internal carotid artery—mainly the The rich vascular supply of the eyelids is through ophthalmic artery—and branches of the facial artery marginal and peripheral arcades.2,3 Medially a rich accounts for reversal of flow seen when the internal superficial network is formed via anastomoses from carotid artery is obstructed.2 both the internal and external carotid artery sys- tems (Fig 1). Innervation Sensation to the periorbital area is via the first and second branches of the trigeminal nerve. The motor supply to the orbicularis oculi muscle is from the temporal and zygomatic branches of the facial nerve, which enter the muscle from its deep sur- face. Ouattara and coworkers5 find three common patterns of innervation of the orbicularis (Fig 2). In the most common variant, present in 63.3% of their cases, the muscle is innervated by a superior plexus fed by temporal and superior zygomatic branches and an inferior plexus fed by inferior zygomatic and superior buccal branches. In the lower lid, Mendelson et al6 describe the situation as follows: The zygomatic branches of the facial nerve that Fig 1. Blood supply of the eyelid. ADT=anterior deep innervate the orbicularis oculi enter the pars temporal artery; DN=dorsal nasal artery; F=facial artery; orbitalis at or near its periphery and seem to do so IO=infraorbital artery; L=lacrimal artery; OA=ophthalmic in four distinct locations [Fig 3]. Ultimately, the artery; SO=supraorbital artery; ST=supratrochlear artery. several branches become more superficial as they (Reprinted with permission from Tucker SM, Linberg JV: Vascular enter the suborbicularis oculi fat on the underside anatomy of the eyelids. Ophthalmology 101:1118, 1994.) of the orbicularis. The [zygomatico-facial] nerve, previously The upper marginal arcade is initially quite tortu- considered the main innervation of the orbicularis ous and then straightens out as it passes further oculi, separates from the zygomatic nerve well SRPS Volume 10, Number 8 Fig 2. Common anatomical variations in the innervation of the orbicularis oculi and their relative prevalence. T = temporal branch of facial nerve. SZ = superior zygomatic branch. IZ = inferior zygomatic branch. SB = superior buccal branch. a, 63.3%; b, 16.7%; c, 13.3%. (Reprinted with permission from Ouattara D, Vacher C, Accioli de Vasconcellos JJ, et al: Anatomical study of the variations in innervation of the orbicularis oculi by the facial nerve. Surg Radiol Anat 26:51, 2004.) before the latter passes deep to the zygomaticus major. [The zygomatico-facial nerve] continue[s] its directly horizontal course over the outer surface of the zygomaticus major, within a centimeter of the upper edge of the muscle origin. This orbicularis branch courses immediately outside the pre- zygomatic space as it passes on the inferior surface of the same zygomatic ligament forming part of the inferior boundary of the prezygomatic space, . [and] continues medially onto the surface of the zygomaticus minor, . where it abruptly changes course, from transverse to vertical, to enter the sub- orbicularis oculi fat overlying the zygomaticus minor. It remains in this layer, in the ceiling of the space, as it ascends toward the lid margin [Fig 4]. Fig 3. Pattern of innervation of the orbicularis oculi of the lower Mendelson et al (2002) lid. The branches at 6 o’clock and 7 o’clock course from deep to the parotid-masseteric fascia to become superficial into the 7 sub-orbicularis oculi fat near the retaining ligaments. The dark In the upper lid, Hwang and colleagues follow arrows indicate the three common surgical approaches to the the course of the temporal branch of the facial nerve prezygomatic space. (Reprinted with permission from Mendelson in the orbicularis oculi muscle and designate a haz- BC, Muzaffar AR, Adams WP Jr: Surgical anatomy of the midcheek ard zone where injury to the temporal branch is and malar mounds. Plast Reconstr Surg 110:885, 2002.) likely to occur. On the basis of a study on 20 cadav- ers, the authors found the temporal branch of the Skin and Subcutaneous Tissues facial nerve coursed horizontally along the fibers of the orbicularis oculi muscle with interconnections, Eyelid skin has only 6 to 7 cell layers and averages but did not cross over the superior orbital rim. <1mm thick. The upper eyelid is even thinner than The location of the supraorbital and infraorbital the lower lid in most people. Sebaceous glands are nerves can be predicted by palpating for the more numerous on the medial half of the lids, con- supraorbital notch. Cadaver studies by Wilhelmi tributing to smoother, oilier skin on the nasal side.9 and associates8 place the vertical course of the Eccrine sweat glands are found throughout the eye- supraorbital and infraorbital nerves approximately lid, while apocrine glands (Moll) are more commonly 16–17mm from the medial canthus along the medial found near the lid margin. The sebaceous glands of one third of the orbit. Zeis are associated with the eyelashes.9 2 SRPS Volume 10, Number 8 Fig 4. The temporal approach to the prezygomatic space passes deep to the lower temporal branches of the facial nerve (TFN) to the orbicularis. The zygomatico-facial nerve (ZFN) is the only structure crossing the space, and lies directly cephalad to the zygomaticus minor muscle. (Reprinted with permission from Mendelson BC, Muzaffar AR, Adams WP Jr: Surgical anatomy of the midcheek and malar mounds. Plast Reconstr Surg 110:885, 2002.) In the Western upper eyelid, fascial bands from border of the tarsus. Asians usually lack a palpebral the levator palpebrae pass through the orbicularis fold because the levator expansions do not pen- oculi muscle and insert into the skin from the ciliary etrate the orbital septum. In the lower eyelid of margin to the level of the palpebral furrow (Fig 5A). Europeans, fibrous bands from the orbital septum The skin superior to the furrow is nonadherent and pass through the orbicularis oculi and insert into the relatively mobile; this transition from adherent skin, forming an inferior palpebral furrow. As in the pretarsal skin to mobile preseptal skin forms the upper upper lid, Asians lack these fascial extensions and eyelid fold, which typically runs along the superior therefore show no palpebral crease (Fig 5B). Fig 5. A. Sagittal section of upper eyelid in left, Westerners and right, Asians. The levator expansions penetrate the orbital septum and orbicularis muscle to attach to the skin in Europeans. These extensions are lacking in Asian eyelids. (Adapted from Sheen JH: Supratarsal fixation in upper blepharoplasty. Plast Reconstr Surg 54:424, 1974.) Fig 5. B. Sagittal section of lower eyelid in left, Westerners and right, Asians. The capsulopalpebral fascia in the lower lid corresponds to the levator in the upper lid. (Reprinted with permission from Wolfort FG, Kanter WR, eds: Aesthetic Blepharoplasty. Boston, Little Brown, 1995.) 3 SRPS Volume 10, Number 8 Orbicularis Oculi Muscle The orbicularis oculi consists of palpebral and orbital portions, with the palpebral portion further subdivided into pretarsal and preseptal portions. Medially, the orbital portion of the muscle origi- nates directly from the bony orbital rim and the medial canthal tendon. Superiorly, the orbital por- tion of the muscle overlies both the frontalis and corrugator muscles. Inferiorly, the orbicularis muscle attaches indirectly to the orbital rim by means of the orbicularis retaining ligament (Fig 6), overlying the origins of the levator muscles to the upper lip. The orbicularis retaining ligament separates the prezygomatic space from the preseptal space (Fig 7). Laterally, the ligament merges into the lateral orbital thickening.10 The upper and lower portions of the preseptal orbicularis converge at the lateral canthal raphe.2 Fig 7. The orbicularis retaining ligament (ORL) indirectly at- taches the orbicularis oculi (OO) to the periosteum of the orbital rim and separates the prezygomatic space from the preseptal space. (Reprinted with permission from Muzaffar AR, Mendelson BC, Adams WP Jr: Surgical anatomy of the ligamentous attach- ments of the lower lid and lateral canthus. Plast Reconstr Surg 110:873, 2002.) sac, while medial movement produces positive pres- sure and is responsible for the lacrimal pump. The pretarsal muscle is closely adherent to the tarsal plate. The pretarsal muscle is an integral com- ponent of lid closure and helps to maintain the structural integrity of the tarsal plate.11 Medially the pretarsal muscles insert on the medial orbital wall Fig 6. Attachments of the orbicularis oculi in the lower lid. both anterior and posterior to the lacrimal sac. Lat- Medially, the muscle originates directly from the orbital rim above the origin of the levator labii superioris (LLS).