Eyelid Defects Involving the Eyelid Margin
Small upper eyelid defects
Small defects involving the upper eyelid margin can be repaired by primary closure if this technique does not place too much tension on the wound (Fig 11-9). Primary closure is usually employed when one-third or less of the eyelid margin is involved; if a larger area is involved, advancement of adjacent tissue or grafting of distant tissue may be required. The superior limb of the lateral canthal tendon can be released to allow 3–5 mm of medial mobilization of the remaining lateral eyelid margin. Care must be taken to avoid the lacrimal ductules in the lateral upper eyelid; removal or destruction of these ductules may lead to chronic dry eye problems in the patient. Postoperatively, the eyelid may appear tight and ptotic due to traction, but it typically relaxes over several weeks.
Moderate upper eyelid defects
Moderate defects of the upper eyelid margin (33%–50% margin involvement) can be repaired by advancement of the lateral eyelid segment and temporal tissue. The lateral canthal tendon is released, and a semicircular skin flap is made below the lateral eyebrow extending from the canthus to allow for further eyelid mobilization. The temporal branch of the facial nerve should be avoided when incising the flap. Tarsal-sharing procedures involving the lower eyelid may be required in younger patients with less eyelid laxity.
Large upper eyelid defects
Upper eyelid defects involving more than half of the upper eyelid margin are likely to require eyelid-sharing techniques. After a horizontal subciliary incision in the lower eyelid tarsus, a full-thickness lower eyelid flap is advanced into the defect of the upper eyelid behind the remaining lower eyelid margin (Cutler-Beard flap; Fig 11-10). This procedure requires a second procedure to open the eyelids, and often results in a thick and relatively immobile upper eyelid. Alternatively, a tarsoconjunctival flap from the lower eyelid used in conjunction with an overlying skin graft may result in better cosmesis. Eyelid-sharing procedures are less optimal in monocular patients or in children in whom deprivation amblyopia may be a concern. A free tarsoconjunctival graft taken from the contralateral upper eyelid and covered with a skin–muscle flap may be an option if adequate redundant upper eyelid skin is present.
Small lower eyelid defects
Small defects of the lower eyelid (margin involvement of less than one-third) can be repaired by primary closure (Fig 11-11). In addition, the inferior crus of the lateral canthal tendon can be internally or externally released so that there is an additional 3–5 mm of medial mobilization of the remaining lateral eyelid margin.
Moderate lower eyelid defects
Semicircular advancement or rotation flaps, which have been described for upper eyelid repair, can also be used for reconstruction of moderate defects in the lower eyelid. The most commonly used flap in such cases is a modification of the Tenzel semicircular rotation flap. Tarsoconjunctival autografts harvested from the underside of the upper eyelid may be transplanted into the lower eyelid defect for reconstruction of the posterior lamella of the eyelid. When tarsal grafts are harvested, the marginal 4–5 mm height of the tarsus is preserved to prevent distortion of the donor eyelid margin. Tarsoconjunctival autografts may be covered with skin flaps or skin–muscle flaps. Cheek elevation (suborbicularis oculi fat lift) may be required to avoid ectropion and vertical traction on the eyelid. Alternatively, a tarsoconjunctival flap developed from the upper eyelid and a full-thickness skin graft can be used (discussed in the next subsection).
Large lower eyelid defects
Defects involving more than half of the lower eyelid margin can be repaired by advancement of a tarsoconjunctival flap from the upper eyelid into the posterior lamellar defect of the lower eyelid. The anterior lamella of the reconstructed eyelid is then created with an advancement skin flap or, in most cases, a free skin graft taken from the preauricular area, the postauricular area, or the contralateral upper eyelid (modified Hughes flap). The modified Hughes flap therefore results in placement of a bridge of conjunctiva from the upper eyelid across the pupil for several weeks (Fig 11-12). The vascularized pedicle of conjunctiva is then released in a staged, second procedure once the lower eyelid flap is revascularized, typically 3–4 weeks later. Eyelid-sharing techniques should be used cautiously in children, because deprivation amblyopia may develop. Large rotating cheek flaps (Mustardé flap; Fig 11-13) can work well for repair of large anterior lamellar defects, but they may require a tarsal substitute such as a free tarsoconjunctival autograft, hard-palate mucosa, or a Hughes flap for posterior lamella replacement. Both the cheek rotation flap and the semicircular rotation flap frequently result in a rounded lateral canthus, which can be mitigated by creating a very high incision toward the lateral end of the eyebrow, in which the incision emanates from the lateral commissure. Free tarsoconjunctival autografts from the upper eyelid covered with a vascularized skin flap have also been used to repair large defects. This type of procedure has the advantage of requiring only 1 surgical stage and prevents temporary occlusion of the visual axis.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.