A 20-year-old man was admitted to our hospital for a pigmented lesion of his left lower eyelid (Figure 1). Six years before, the upper eyelid portion of a divided nevus involving the lateral two-thirds of the upper and lower eyelids and the lateral canthus, with an extension 2 mm into the tarsal conjunctiva, was excised, sparing the portion along the ciliary margin and conjunctiva. The defect was reconstructed using a full-thickness skin graft taken from the retroauricular area, and the lower eyelid lesion was excised, sparing the pretarsal portion and conjunctiva. The defect was reconstructed using a primary closure and half Z-plasty. During this visit, the remnant lesion in the pretarsal portion of the lower eyelid was excised but not the ciliary margin. How would you repair this defect?
Resolution of the Conundrum
After excision of the lesion, a bipedicled skin flap fashioned from the remaining inferior eyelid tissue was prepared to cover the resulting pretarsal defect (Figure 2, left). The flap was fully dissected from the underlying orbicularis muscle. After advancing the flap vertically to the defect site (Figure 2, right, and Figure 3), both sides of the defect at the ciliary margin were minimally trimmed, and the upper margin of the flap was sutured using 6–0 polyglactin 910 sutures with a slightly wider interval on the flap than on the ciliary margin to correct a length discrepancy between the upper margin of the flap and the defect of the ciliary margin. The rest of the margin was sutured using 6–0 synthetic, monofilament, nonabsorbable polypropylene sutures, and a full-thickness skin graft from the retroauricular area was used to resurface the donor site. No intraoperative or postoperative complications were noted. Two months later, the appearance of the patient was cosmetically acceptable, although there were small residual lesions on the ciliary margin (Figure 4). Irregularities appeared in the margins where the skin graft interfaced with the flap and the intact eyelid skin, possibly due to a scar contracture of the skin graft or thickness difference between the skin graft and the surrounding tissues. If the cause was the former, the irregularities could improve spontaneously with the passage of time.
Discussion of Considerations
Surgery is the most effective treatment for a divided nevus of the eyelid, but surgical treatment does not need to be completed in a single step. Most patients with such a lesion primarily want to address aesthetic problems, so various methods can be used step by step with low comorbidity. Reconstruction of the pretarsal portion, which is usually the last to be treated after sequential treatments for a divided nevus of the eyelid, is difficult because of the number of important anatomic structures in the eyelid.
There is a difference between treatment of a nevus in the eyelid and other reconstructive procedures for malignant tumors or posttraumatic defects. Although a congenital melanocytic nevus involves the ciliary margin and the anterior lamella of the eyelid, the involved ciliary margin is not routinely removed, making it easier to reconstruct the defect and producing few functional problems. The decision to excise and reconstruct the ciliary margin is made only in select cases, such as with the presence of wart-like excrescences on the eyelid margin, which cause corneal irritation. Malignant transformation of the divided nevus has not been reported, but if it occurs, it requires careful follow-up.
A divided nevus of the eyelid is typically repaired using skin grafts.[1-4] Margulis and colleagues reported that, for an intermediate-size nevus that does not extend beyond the eyelid crease, nonexpanded full-thickness skin grafts can be used for reconstruction, whereas for large nevi beyond the eyelid crease, supraclavicular expanded full-thickness skin grafts are the first choice for reconstruction. This latter approach avoids problematic scarring at the junction lines between smaller grafts and results in less of a patchwork appearance in the outcome. Grafts taken from surrounding skin, such as the retroauricular area, the upper eyelid of the affected eye, or the unaffected eye, have been successful in light-skinned patients for treatment of a divided nevus,[1-4] but the incidence of ectropion after full-thickness skin grafting of the lower eyelid is high and has been reported to be up to 14.2%, so the authors reconstructed the defect of the pretarsal portion in the lower eyelid using a bipedicled skin flap to decrease the incidence of ectropion.
Several papers have reported the use of a bipedicled flap in the context of lower eyelid reconstruction,[6-8] but the flaps elevated from the upper eyelid were transferred to lower eyelid defects for ectropion repairs or total reconstruction after malignant tumor removal in the lower eyelid and not a divided nevus of the eyelid. The flap used in our case was not a myocutaneous flap including the orbicularis ocularis muscle but rather a skin flap.
An advantage of this flap for repair of pretarsal defects of the lower eyelid is its physiologic similarity to the removed tissue. In addition, if scar contracture occurs in the pretarsal portion adjacent to the ciliary margin, it can easily cause ectropion, but if the pretarsal portion is reconstructed using highly vascularized tissue, the incidence of scar contracture is low, and although scar contracture can occur in the preseptal or orbital portion of the eyelid, the flap acts as a barrier to prevent the downward pull of the ciliary margin. Third, it is safe and easy to dissect a flap with adequate circulation because of the rich vascularity of the eyelids, and the subdermal vessels of the eyelids are elongated and arranged parallel to the palpebral fissure, which coincides with the long axis of the flap.
Most divided nevi of the eyelids are surgically removed for aesthetic reasons, and reconstruction causes few aesthetic problems in the donor and recipient sites, but the operators do not have a wide range of choices, so a flap is an alternative reconstruction method for a divided nevus.
- Herein we report the reconstruction of a defect of the pretarsal portion of the lower eyelid using a bipedicled skin flap after excision of a divided nevus.
- It is physiologically similar to that removed.
- It acts as a barrier to prevent the downward pull of the ciliary margin when developing severe contracture of the inferior eyelid tissue.
- It is safe and easy to dissect the flap.