Introduction
In a full-thickness reconstruction of the upper or lower eyelid it is important to reconstruct the posterior lamella of the lid to give support to the reconstructed anterior lamella. In the upper lid it is essential that the posterior lamella is lined with mucosa. In the lower lid this is less important but still desirable. If a skin flap is available for the anterior lamella the posterior lamella may be reconstructed with either a flap or a graft. If, however, a free skin graft is to be used for the anterior lamella the posterior lamella must be reconstructed with a vascularised flap.
To estimate the length of posterior lamella required, pull gently on the edges of the defect to reduce the horizontal extent and eliminate horizontal lid laxity. The remaining defect is the length of the reconstruction required.
Classification
Grafts
oral mucous membrane
tarsal plate
hard palate
nasal septal cartilage
tarsomarginal graft
Flaps
Hughes’ tarsoconjunctival flap
lateral periosteal flap
tarsal transposition flap (Hewes)
Grafts to reconstruct the posterior lamella
Choice of operation
In the upper lid tarsal plate from the same or opposite upper lid, oral mucous membrane, hard palate or a tarsomarginal graft is used.
In the lower lid the posterior lamella must provide added support because of the effect of gravity. Oral mucosa alone will not be sufficient to support a thin skin flap; it may be acceptable, although not ideal, as a lining for a thicker flap. In general a graft of tarsal plate, hard palate, sclera or cartilage is preferable.
The reconstructed lids need support from the canthal tendons. If a canthal tendon has been compromised in the surgical excision it must be reconstructed with one of the methods described below.
Preparing the grafts
See Ch. 2 , Sect. D , for methods of taking oral mucous membrane, auricular cartilage, tarsal plate, hard palate and sclera. See 16.2 for the method of taking nasal septal cartilage with mucoperichondrium and 16.3 for taking a tarsomarginal graft.
16.1
Using grafts for the posterior lamella
The posterior lamellar graft must be sutured to tarsal plate or canthal tendon, at the ends of the defect, with interrupted or continuous 6/0 absorbable sutures (see Fig 15.10d , Fig 15.11b ).
If the canthal tissues are absent medially the attachment should be to the periosteum posterior to the normal attachment of the medial canthal tendon – ideally to the periosteum of the posterior lacrimal crest – with two 4/0 or 5/0 nonabsorbable sutures.
Laterally, a new canthal tendon may be reconstructed with a flap of periosteum (see 16.5 ) or a flap of tarsal plate transposed from the upper lid.
The posterior lamellar graft must be adequate vertically to lie without tension against the anterior lamella. An excess of mucosa wrapped over the reconstructed lower lid margin can result in persistent redness along the margin (see 15.18e, post ). This can be avoided by trimming the mucosa so that it is level with the lid margin before suturing. If the posterior lamella is secure at the lid margin at the end of the procedure the suture can be omitted.
Some degree of contraction occurs with all posterior lamellar grafts. Those without a mucosal lining, such as sclera, may cause irritation until they are epithelialised.
Alternative procedures
16.2
Nasal septal cartilage with mucoperichondrium
This cartilage graft has the advantage over auricular cartilage (see 2.18 ) of being lined with mucosa although it is rather thick mucosa. The cartilage, also, is thicker than auricular cartilage but it provides a useful support in some situations such as a Mustardé cheek rotation flap.
Bleeding may be reduced by packing the nose in the anaesthetic room with ribbon gauze soaked in 4% cocaine. In theatre inject 1 : 200,000 adrenaline submucosally on one side of the septum. Insert a nasal speculum on the side opposite to the injection. Adequate access to the nasal septum can usually be obtained with a nasal speculum alone. If difficulty is experienced the exposure is improved by incising through the alar base and elevating the lateral wall of the nostril.
Incise the nasal septal mucosa just above and parallel to the mucocutaneous junction within the nose. Deepen the incision to make a partial-thickness cut through the septal cartilage.
Cut through the remaining cartilage with a Rollett’s rougine. Take care not to perforate the opposite perichondrium and mucosa. If a perforation is made suture it with 6/0 plain catgut.
Dissect the intact mucoperichondrium from the opposite side of the cartilage using a blunt periosteal elevator (e.g. MacDonald).
Protect the intact mucoperichondrium with the blunt dissector and cut the graft of cartilage and attached mucosa with scissors from each end of the original incision.
Use angled scissors or a blade to cut the proximal end of the composite graft. Shave to reduce the cartilage, if necessary, to the required thickness.
Repair the alar base if it was opened.
To dress the nose cut two fingers from an operating glove, pack each with paraffin gauze and lubricate each with liquid paraffin. Place one finger in each side of the nose. Remove on the first postoperative day and use antibiotic and vasoconstrictive drops for a month.
If the intact mucosa of the opposite side of the nose is incised close the defect with interrupted 6/0 absorbable sutures.
16.3
Tarsomarginal graft
Because a defect of a quarter of the length of an eyelid margin can be closed directly, free grafts of this size, which include the lid margin, may be excised from one or more of the normal lids and used to reconstruct an upper or lower lid defect. The skin and orbicularis muscle are removed from the surface of the graft but the lid margin and lashes are left intact. The graft of tarsal plate and lid margin is sutured into the defect and covered with a local skin flap. There should be minimal tension across the graft/s when sutured into the defect. Remove all skin sutures at 5 days and the lid margin sutures at 7 days.
Because the blood supply is from the skin flap two or even three tarsomarginal grafts may be sutured in a row to reconstruct larger defects.
The graft may necrose particularly if there is significant tension across it. The resulting notch may be excised when healing has occurred, after 3 to 6 months, and the defect reconstructed by an alternative method.
Flaps to reconstruct the posterior lamella
Choice of operation
The only posterior lamellar flap is tarsal plate with its blood supply intact through a pedicle of conjunctiva. The donor site is always the upper lid tarsus because the lower tarsal plate is too narrow to use as a graft. The Hughes’ tarsoconjunctival flap (16.4) is the most commonly used but variations have been described, including the Hewes transposition flap (16.6) which also provides support to the lid laterally. They are indicated for shallow lower lid defects which do not extend beyond the lid. In larger defects these procedures can be used to reconstruct the eyelid, and an extra graft or flap can be added for the extension into the cheek or canthus.
The lateral canthal tendon may be reconstructed to support the lateral canthus by fashioning a flap of periosteum (16.5) at the lateral orbital rim. The Hewes flap (16.6) mentioned previously is an alternative. Support at the medial canthus relies on direct attachment to the periosteum (see 7.7 , 7.8 ) or to a transnasal wire (see 18.3 ).
16.4
Hughes’ tarsoconjunctival flap ( )
The use of the Hughes’ flap is indicated for relatively shallow lower lid defects which do not extend much beyond the inferior border of the tarsal plate. A broad strip of upper tarsal plate on a pedicle of conjunctiva is used to reconstruct the posterior lamella of the lower lid. It may be covered with a skin graft (16.4g) or flap. The pedicle is divided after a few weeks.
Evert the upper lid. Insert a stay suture of 4/0 silk through the tarsal plate close to the lid margin and evert the lid over a Desmarres retractor. Estimate the length of posterior lamella required by gentle traction on the edges of the defect to check that there will be sufficient horizontal length of tarsal plate for the posterior lamellar reconstruction. Mark a line 4 mm from and parallel to the lid margin as far as the superior tarsal border medially and laterally.
Incise the tarsal plate to enter the easily identified pretarsal space. Extend the incision medially and laterally to the full extent of the mark. Turn the flap of tarsus down by dissection in the pretarsal space as far as the superior border of the tarsal plate, leaving the superior attachment to Muller’s muscle and the conjunctiva intact.
Identify Muller’s muscle as it inserts along the superior tarsal border. It can be disinserted from the tarsal border, taking care not to damage the underlying conjunctiva. This reduces the risk of upper lid retraction following the second stage of the procedure. Alternatively, Muller’s can be left intact at this stage and recessed at the second stage. This improves the blood supply to the graft. Extend the edges of the conjunctiva–Muller’s part of the flap vertically for 3 to 4 mm to lengthen the flap.
When the tarsoconjunctival flap is in place measure the size of skin graft required.
After about 3 weeks divide the pedicle 2 to 3 mm superior to the tarsal plate and skin graft taking care that no skin remains behind the upper lid. Trim the mucosal edge of the flap (now divided) so that it is flush with the edge of the skin graft at the lid margin. A suture along the lid margin is usually not necessary.
The upper lid retractors will have been advanced by the procedure and must be recessed to prevent upper lid retraction. To do this, dissect between the conjunctiva and the retractors until the lid is at a satisfactory level. Allow the proximal conjunctiva to retract. A downward traction suture on the upper lid for 24 hours may be needed.
Retraction of the upper lid may follow the second stage if the upper lid tissues have not been freed sufficiently. Dissect further between the conjunctiva and the upper lid retractors until the lid is at the correct level.
16.5
Lateral periosteal flap
This technique is used to support the upper or lower lid, or both, laterally when the lateral canthal tendon is inadequate. It is useful in lid reconstruction when lateral fixation of the posterior lamella is required, or in any situation where the tendon is lax or absent and the lateral canthus has moved medially (the case illustrated).
Make a horizontal incision from the lateral canthus to expose the lateral orbital rim. At the level of the lateral canthal tendon mark two horizontal lines on the periosteum, 8 to 10 mm apart, extending from the medial border of the lateral orbital rim to the temporalis fascia laterally. If support for both lids is required, cut a broader strip of periosteum to allow it to be split later. Mark the lateral extent of the flap with a vertical line.
Care is needed in the design of the flap to ensure that the canthus is held at the correct level. With time some relaxation of the flap may occur.
16.6
Hewes tarsal transposition flap
This flap of tarsoconjunctiva is harvested from the upper lid and remains attached at the lateral canthal tendon to support the lower lid. It is most suitable for defects of the lower lid extending to the lateral canthus but not including the upper limb of the lateral canthal tendon. It may also be used in other defects of the lower lid when, for example, a lateral cantholysis, Tenzel flap, McGregor flap or Mustardé cheek rotation flap has been used for reconstruction and lateral support is required.