Introduction

The reconstruction of large eyelid defects or scars can present a significant clinical challenge; there is a need for static eyelid height that permits dynamic function and tear production while simultaneously preventing corneal exposure due to eyelid scarring and retraction. Accomplishing these goals in an aesthetically sensitive area relies on eyelid-sharing flap techniques. The underlying principle of eyelid-sharing flaps is replacing "like-with-like"; eyelid-sharing flaps provide well-vascularized local tissue with an excellent color and texture match.[1][2] The main goals of eyelid-sharing flap procedures are recreating a functional eyelid that protects the corneal surface, providing aesthetically pleasing reconstruction, and limiting the morbidity of the donor eyelid.

Considering the reconstructive ladder is imperative in any attempt to repair a defect. The components of the reconstructive ladder, from simplest to most complex, include healing by secondary intention, immediate or delayed primary closure, employing split- or full-thickness skin grafts, using tissue expanders, or executing an adjacent tissue transfer, regional flap, or free flap. More minor eyelid defects may be well served using a free autograft or adjacent tissue transfer using a local or rotational flap. However, reconstruction of defects encompassing more than 50% of the eyelid benefits from a staged procedure, allowing the transposition of vascularized tissue with the later division of the vascular pedicle performed after the 1 to 4 weeks required for neovascularization. The staged eyelid-sharing flap techniques most commonly employed in lower and upper eyelid reconstruction are the Hughes and Cutler-Beard flap procedures.[3] 

Wendell Hughes first described his eponymous tarsoconjunctival flap in 1937 to reconstruct lower lid defects encompassing more than 33% of the total lid area. This technique recreates a well-vascularized posterior lamella; the anterior lamellae can be reconstructed with a skin graft.

Norman Cutler and Crowell Beard described their eponymous full-thickness cutaneoconjunctival flap in 1955 to reconstruct upper eyelid defects measuring more than 50% of the lid margin. Such defects are commonly encountered in the setting of congenital abnormalities, the resection of malignancies, and eyelid trauma, including burns.[1] The original description of the Cutler-Beard flap technique reconstructs the anterior and posterior lamellae but not necessarily the tarsus.

The Hughes and Cutler-Beard techniques have undergone some modifications in the intervening years since their original descriptions, yet both remain workhorses for reconstructing significant eyelid defects.

Anatomy and Physiology

Anatomy of the Upper Eyelid

The vascular supply of the upper eyelid is the marginal and peripheral vessel arcades, which are closely associated with the tarsus.[4] The arcades run horizontally deep to the aponeurosis.

The upper eyelid comprises 3 lamellae: anterior, middle, and posterior.

The anterior lamella comprises the skin and orbital and palpebral parts of the orbicularis oculi muscle.[4] The muscular fibers condense at their lateralmost extent to form the lateral canthal tendon, which inserts onto the tubercle of Whitnall at the posterior border of the lateral orbital rim.[4]

The middle lamella comprises the orbital septum and intervening fat between the muscular layer and septum.[4] The orbital septum is derived from the area where the arcus marginalis fuses inferiorly with the periosteum of the orbital rim.[5]

The posterior lamella comprises the levator muscle, its anterior and posterior split aponeurosis, the tarsus, and the conjunctivae.[4][6] The anterior layer of the aponeurosis of the levator courses thinly over the tarsus and attaches to the orbital septum. The posterior layer courses toward the base of the tarsal plate.[6] The muscle of Mueller is located deep to the aponeurosis and is controlled via sympathetic innervation.[4][6] The tarsal plate is secured medially and laterally by canthal tendons and contains meibomian glands to stabilize a tear film.[6]

The upper eyelid also contains the central and medial fat pads and the lacrimal gland.[4] The suspensory ligament of Whitnall, also known as the superior transverse ligament, spans from the trochlea to the lacrimal gland and is critical in directing levator function.

Anatomy of the Lower Eyelid

The lower eyelid is less complex and dynamic than its upper counterpart and can also be divided into anterior, middle, and posterior lamellae.[5]

The anterior lamella comprises skin and muscle; the middle lamella contains the septum and fatty and fibroadipose tissues.[4][5] The posterior lamella comprises the retractors, tarsus, and conjunctivae.[4] The ligament of Lockwood is also found in the posterior lamella and supports the globe.

The orbital septum is thicker laterally than it is medially.[4][5] The suborbicularis oculi fascia covers the septum anteriorly and is distinct from the orbital fat pads.[4][5] The lower eyelid contains the lateral, medial, and central fat pads; the inferior oblique muscle divides the central and medial fat pads.[5] The central and lateral fat pads are arbitrarily divided by the ligament of Lockwood, coursing to its attachment on the inferolateral orbital rim.[4] 

The levator aponeurosis of the upper eyelid is analogous to the lower lid capsulopalpebral fascia. The muscle of Mueller is analogous to the inferior tarsal muscle.

Indications

The Cutler-Beard full-thickness cutaneoconjunctival flap is utilized for full-thickness defects spanning more than 50% of the upper eyelid.[1]

The Hughes tarsoconjunctival flap has been historically used on the lower eyelid and can be employed in cases with full-thickness defects encompassing one-third or more of the lid's total area.[7][8][9] Centralized lesions of the lower lid occupying 60% to 80% of the total area are excellent candidates for the Hughes technique.[7] The Hughes tarsoconjunctival flap can also be employed to address postoperative eyelid retraction.[10][11]

Contraindications

The Hughes and Cutler-Beard eyelid-sharing surgical techniques cannot be employed in patients with defects on both the upper and lower eyelids; involvement of both upper and lower eyelid tissues should prompt recruitment of other tissue.[12] Patients with dry eye symptoms secondary to autoimmune diseases are considered poor candidates for these eyelid-sharing techniques.[9]

While not an absolute contraindication, these eyelid-sharing techniques may be less favorable options for patients who have only one seeing eye, as the flap will cover the cornea for an average of 3 weeks.[12] 

Equipment

The following equipment is required for eyelid-sharing techniques; preferences will vary with the performing surgeon.[13]

• Calipers
• Marking pen
• Corneal protector
• Castroviejo forceps
• Westcott scissors
• Colorado-tip Bovie or Thermal pen cautery
• Desmarres retractor
• Bard-Parker blade, No. 15
• 3-0 or 4-0 silk suture for lid retraction
• 5-0 vicryl or polygalactin sutures
• 7-0 vicryl or polygalactin sutures
• 6-0 nylon suture for skin closure
• Ophthalmic antibiotic ointment
• Compressive dressing materials such as non-adherent gauze, Xeroform, eye patch, or plastic patch
• Ophthalmic topical antibiotic and anti-inflammatory drops [9]

Personnel

The necessary personnel for an eyelid-sharing surgical procedure typically include the following:

• Oculoplastic or facial plastic surgeon
• Surgical first assistant
• Anesthetist
• Circulating or operating room nurse
• Surgical technician or operating room nurse

Preparation

The maximum dimensions of the flaps created using eyelid-sharing techniques are cited as 30 mm horizontally and 7 mm vertically.[9] The exact size and depth of the defect being repaired must be known to design a flap that appropriately covers the reconstruction effort. Surgeons must be prepared to recruit or harvest tissue from elsewhere if a portion of the defect remains uncovered due to horizontal or vertical size limitations of the Hughes or Cutler-Beard flaps.

It is acceptable for the anticipated length of the donor tissue to measure between one-half to two-thirds of the defect length; biological and mechanical creep can compensate for deficiencies of that size over time.[12]

Technique or Treatment

During eyelid-sharing flap procedures, great care must be exercised to protect the cornea. Infiltration with local anesthesia with epinephrine is regularly used in conjunction with general anesthesia. Ophthalmic betadine is commonly used for skin preparation before sterile draping.

Hughes Tarsoconjunctival Flap for Lower Eyelid Reconstruction

To fashion the tarsoconjunctival Hughes flap for lower lid reconstruction, the anterior lamella of the lower lid defect is separated from the orbital septum.[13][14] It is favorable to leave the medial canthal tendon, or at least a cuff of periosteum, to secure the donor flap. After eversion of the upper lid, an incision is made approximately 3 to 4 mm above the lid margin to free the flap from the underlying levator aponeurosis and muscle of Mueller, leaving the superior vascular pedicle intact.[13][14] For larger defects, the tarsoconjunctival flap only repairs the central portion of the defect overlying the cornea, with medial and lateral periosteal recruitment in an oblique fashion to advance tissue from the medial and lateral aspects and achieve the reconstruction of the posterior lamella.[13][14][15] 

The tarsus is sutured to the periosteal flaps with 5-0 or smaller polydioxanone (PDS) or nylon suture.[2][9][14][16] Anterior lamellar skin deficiencies can be covered using a combination of an orbicularis oculi advancement muscle flap and a full-thickness skin graft or skin swing flaps.[2][15] Full-thickness skin grafts should be oversized by 10% to prevent contracture.  

When extending medially, the lower canaliculus is not reconstructed. Once the flap is secured, a compressive dressing is placed for one week.[14] Multiple authors stress the importance of massaging the affected area after dressing removal to improve skin elasticity. The flap can be divided in 1 to 8 weeks; flap division may be performed under local anesthesia as patient factors dictate.[2][9][16]

In the second stage of the procedure, the bridge of the remaining conjunctival tissue is carefully divided while ensuring an adequate pedicle length is harvested to prevent lower lid height contracture.

A video adjunct outlining the Hughes Tarsoconjunctival Flap, performed by RC Allen, MD, PhD, FACS, is available. [University of Iowa, Ophthalmology and Visual Sciences, EyeRounds, Hughes Flap (tarsal-conjunctival flap)].

Cutler-Beard Full-Thickness Flap for Upper Eyelid Reconstruction

The Cutler-Beard full-thickness flap is transposed under the lower eyelid margin. This technique is designed to spare the tarsal plate and avoid damaging the native marginal vascular supply to the lower eyelid.[3] Placing a lower eyelid retraction suture helps maintain tension on the lower eyelid margin. The width of the flap should be the same size as the defect and will be left pedicled inferiorly. The anterior and posterior lamellae of the flap are separated.[17] The anterior and posterior lamellar flaps are passed posterior to the spared lid margin and stretched superiorly to the upper eyelid defect. A three-layer inset is performed, advancing the posterior lamella to the residual conjunctiva using buried sutures to avoid corneal abrasion. In this technique, the anterior and posterior lamella are sutured separately to the levator muscle and orbicularis oculi at the defect site.[17] The skin is secured to the upper eyelid margin.[1]  

The second stage of the procedure is performed in 4 to 8 weeks. During this procedure, the bridge flap pedicle is cut so the superior aspect will fit the size of the defect; the remainder will retract to its original position and can be sutured inferior to the lower eyelid margin.[17][1] Dividing the pedicle with an additional 2 to 3 mm of tissue length is critical to accommodate tissue retraction.

An optional technical modification to create a more favorable contour at the recipient site is reconstructing the tarsus with an inlay graft using auricular cartilage or fascia lata.[1][8][17] The conjunctival layer must be sutured deep before inlay graft placement if this modification is employed.

Complications

The skin and layered tissues of the eyelids are very thin, and close attention must be paid intraoperatively to avoid undue tension when suturing these delicate tissues. Excess tension or frank tearing of tissues will compromise the final size of the available flap and increase the risk of wound dehiscence and flap necrosis.[2][9][16][9][17] Patients can develop postoperative lacrimation disorders due to the proximity of the inferior canaliculus and loss of meibomian glands.[2][3][9]

Retraction and entropion of the upper eyelid after pedicle division were common complications of Hughes’ original technique.[14][7][12] Newer techniques recommend releasing only the levator aponeurosis and leaving the muscle of Mueller attached to the superior portion of the tarsus.[14] The loss of eyelashes in the recipient eyelid may result in corneal irritation from surrounding skin hair.[12] Corneal irritation and ulceration may occur during flap maturation since the flap will cross the cornea before its division.[9][8][12] Patients often reported blurred vision.[12] 

The development of a cicatricial scar may predispose to ectropion after a Hughes reconstruction.[2][16][17] Additionally, lower eyelid retraction is possible over time.[16][17] If extensive periosteal dissection is required during the Hughes procedure, significant edema and bruising may occur, and sensory disturbances may be perceived in the distribution of the zygomaticofacial nerve.

Ectropion of the donor site, entropion or retraction of the recipient site, and the need for supplemental tissue harvest for further reconstruction are complications and drawbacks of the Cutler-Beard technique.[17][1] These complications arise because the Cutler-Beard reconstructive flap does not include tarsus, and effective reconstruction requires employing analogous tissues, such as auricular cartilage.[3]

If the donor eyelid skin is inadequate to cover both the defect and donor sites, the donor site may be left to heal by secondary intention; this increases the risk of postoperative eyelid retraction or contraction.[12]

Other uncommon but possible risks of eyelid-sharing flap reconstructive procedures include symblepharon, lagophthalmos, notching, trichiasis, and exposure keratitis.[9][12] Newly published techniques for single-stage reconstruction procedures decrease temporary morbidity; technique selection should account for the preference and safety of the patient.[8][13][18]

Clinical Significance

The eyes are a critical focal point of cosmesis. Defects around the eye draw significant attention and public concern. Appropriate and expert reconstruction of these defects affects patients aesthetically and functionally. Eyelid-sharing flaps are advantageous because they create better symmetry than other local flaps, such as hinge flaps.[1] Functionally, appropriate reconstruction can prevent epiphora and improve life quality.

Enhancing Healthcare Team Outcomes

Patients of all ages may be affected by large eyelid defects due to congenital abnormalities, trauma, burns, or the resection of cutaneous malignancies near the eye. Patients with eyelid defects are commonly negatively affected aesthetically and functionally. Primary care and ocular health practitioners must know that surgical techniques can correct many eyelid defects, even those encompassing more than 50% of the total eyelid surface area. However, because of the risk of complications, patients who are candidates for reconstructive procedures of the eyelid must be treated by experienced surgeons with specific knowledge and expertise in this complex anatomical area. Although the Hughes and Cutler-Beard eyelid-sharing reconstructive flap techniques are frequently employed to correct large eyelid defects, newly published techniques for single-stage reconstruction procedures that decrease temporary morbidity exist. Therefore, team members must be aware of all possible surgical options and select the procedure that best suits the situation while promoting patient safety and accommodating patient preferences.[8][13][18]

Providing optimal outcomes to patients undergoing eyelid reconstructive procedures requires an interprofessional team, with all members actively engaged in patient counseling and identifying, evaluating, and managing postoperative complications. Additionally, patients require the active engagement of an ophthalmologist to ensure optimal visual outcomes following these reconstructive procedures.