provides excellent structural support and an inherent blood supply. The main disadvantage is obscuration of the pupil by the tarsoconjunctival bridge for 4–8 weeks.

To begin the flap formation, the inferior border of the defect is squared off with a #15 blade to create a rectangular defect with the lateral and medial edges perpendicular to the lid margin. The edges are advanced centrally with forceps, and the horizontal defect is measured. A lateral canthotomy may be employed to increase horizontal movement and reduce the width of the defect.

The ipsilateral upper lid is everted over a chalazion clamp. A three-sided flap is harvested on the central tarsal conjunctival surface of the upper lid with a #15 blade. The incision should be at least 4 mm from the lid margin to minimize postoperative entropion, contour deformities, loss of lashes, and trichiasis. Vertical incisions through the tarsus and conjunctiva are directed superiorly in a plane perpendicular to the lid margin. The flap is undermined from the overlying levator aponeurosis and orbicularis muscle with Wescott scissors. Dissection is continued above the superior tarsal border between the conjunctiva and Mueller’s muscle toward the superior fornix. The tarsoconjunctival flap is then mobilized into the lower lid defect so that the upper lid superior tarsal border is aligned with the lower lid margin remnant. Interrupted partial-thickness 5-0 Vicryl sutures are passed through the tarsus to secure the lateral and medial edges of the flap to the tarsal stumps. Finally, interrupted and running 7-0 Vicryl sutures are used to secure the inferior edge of the flap to the cut edge of the inferior forniceal conjunctiva and lower eyelid retractors.

The second stage of the Hughes procedure is undertaken 4–8 weeks later. It is delayed until the reconstructed lower lid has established its new blood supply and sufficient time has passed to counteract the downward contractile forces of scar maturation and gravity. The flap is incised 0.5–1.0 mm above the new lower lid margin with blunt Wescott or Stevens scissors. Care is taken to avoid traumatizing the underlying cornea. The excess mucosa from the lower portion of the flap is left to retract or sutured to a skin incision made along the new lid margin with a running 7-0 Vicryl suture. This process establishes the new mucocutaneous border. The superior portion of the flap is allowed to retract under the upper lid.

The anterior lamella may be addressed with either a full-thickness skin graft or an advancement flap. A tarsoconjunctival graft will serve as a vascular source for a skin graft.

32.2.2.3 Free Tarsal Graft/Hard Palate Graft + Flap

The posterior lamella may be repaired with a free tarsal graft or a hard palate graft. The anterior lamella may be repaired with a myocutaneous advancement flap, an ellipse sliding flap, or a unipedicle flap. The newly reconstructed eyelid should be kept on stretch to prevent retraction during the healing process. A 4-0 silk suture should be placed through the newly created lid margin. The suture is secured to the forehead with Benzoin and paper tape and kept in place for 2 weeks.

Summary: Special Circumstances

•Medial canthal defects may be closed with a glabellar flap. This advancement of local tissue not only provides wound closure but allows for repair with tissue of adequate depth. Other special circumstances include the use of a galeal or pericranial flap in cases of an insufficient vascularized pedicle and the use of a tissue expander in patients with deficient anterior lamella.

32.3Special Circumstances

32.3.1 Medial Canthal Defect

Defects of the medial canthus have additional considerations. First, the lacrimal system must be evaluated. If there is uncertainty regarding the state of the canaliculi, a 00-Bowman probe may be used to check for defects. The punctum is first dilated. For the upper lid, the Bowman probe is placed into the punctum and directed superiorly (inferiorly for the lower lid) for approximately 2 mm. It is then angled toward the medial canthus through the canaliculus until a hard stop is felt. If the canaliculus is intact, the Bowman probe that has been placed into the lacrimal system should not be visible. If canalicular defects are encountered, they must first be repaired.

One option is to place a mini Monoka stent into the lacerated canalicular lumen. The stent is first trimmed to the appropriate length. After placement, the edges of the lacerated canaliculus are reapproximated with a few interrupted 7-0 Vicryl sutures.

If the canalicular defect is too medial for a Monoka stent, a donut silicone stent may be placed. A pigtail lacrimal probe is passed through the intact opposing canaliculus and into the proximal portion of the lacerated canaliculus. It is then threaded through the severed distal portion. A 6-0 Prolene is threaded through the eyelet at the tip of the probe. The probe’s path is reversed and separated from the Prolene which alone now maintains the canalicular system. Next, a piece of silicone stent (~26–27 mm in length) is guided over the Prolene. The suture ends are then tied together and the knot is trimmed. The knot is then rotated to face the common canaliculus. Reconstruction is now directed toward the soft tissues.

32.3.1.1 Glabellar Flap

A glabellar flap is an excellent method of reconstructing an anterior lamellar defect of the medial canthal region. It is a modified V- to Y-rotation flap [3]. First, an inverted V incision is outlined from the midpoint of the glabella just above the brow at an angle less than 60°. Both segments of the flap should extend below the brow with the longer portion joining the lateral aspect of the defect. The previously outlined skin and subcutaneous tissue are incised with a #15 blade and then undermined extensively with Stevens scissors. It is then rotated into the defect. The apex of the flap is placed at the lateral edge. Once the tip of the flap is trimmed to fit the defect, the flap is secured with buried anchoring, interrupted 5-0 Vicryl sutures. The skin is then closed with interrupted and running 7-0 Vicryl sutures. The donor site is sutured in a V- to Y-closure in two layers. The donor site closure may induce a shortening of the interbrow distance. Occasionally, the flap requires a secondary debulking 6–8 weeks later at its base if the tissue from the donor forehead glabellar region is thicker than that of the recipient medial canthus.

32.3.2 Insufficient Vascularized Pedicle

Some flaps are too large to close primarily or with local tissue recruitment. Because two free grafts overlying each other will not survive, additional methods of repair must be employed to provide an inherent blood supply.

Galeal and pericranial flaps provide well-vascularized tissue beds upon which further reconstruction may be based [9]. Skin is not transposed with a galeal or pericranial flap. Bunching over the nasal bridge is less of concern secondary to the thinner nature of these flaps when compared to a glabellar flap. The galeopericranial flap is thought to be superior to the pericranial flap because of its increased vascularity.

The five layers of scalp’s soft tissue are the skin, subcutaneous soft tissue, galea aponeurotica, subgaleal loose areolar tissue, and periosteum. The pericranium consists of the periosteum and the overlying subaponeurotic loose connective tissue. It is contiguous with the deep temporal fascia in the temporal region. The pericranium also has a dual blood supply, which ensures the viability of a pericranial flap. The galea aponeurotica is composed of dense fibrous tissue.

The posterior lamella is first reconstructed prior to the repair of large upper eyelid defects. The soft tissue defect is then filled with a galeopericranial or pericranial flap. To begin, a standard bicoronal incision is made over the vertex of the skull. A transcoronal incision provides access to the pericranium of the forehead. The plane of dissection is between the subcutaneous tissue and the galea for a galeopericranial flap. The plane for pericranial flaps is subgaleal. The loose areolar tissue and periosteum of the frontal bone are left intact. Dissection proceeds toward the supraorbital rim while care is taken to leave the supraorbital and supratrochlear neurovascular bundles undisturbed. Dissection stops where the vessels enter the base of the flap. The pericranium and galea are incised and elevated from the frontal bone with an elevator. The flap is mobilized and turned down anteriorly through the skin defect. It may be turned in multiple arcs for reconstructive purposes. The length, width, angle, and shape are tailored for the specific deformity to allow for adequate rotation and coverage. It is important to avoid a transverse incision of the flap 2 fingerbreadths above the superior orbital rim because the frontalis nerve enters the frontalis muscle in this area. Once the flap is in place, it serves as a well-vascularized bed for a full-thickness skin graft.

32.3.3 Insufficient Anterior Lamella

Very large anterior lamellar defects may require additional methods beyond skin grafts and flaps. Tissue expansion has been used in periocular reconstruction