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Putting It Back Together
By Marianne Doran
 
 

A primer on reconstruction techniques for eyelid lesions.

Reconstructing an eyelid after excision of a lesion can be challenging. Although defects from small lesions may be amenable to direct closure, larger lesions often require the use of flaps, free tissue grafts or both. Nonetheless, reconstruction of a lower lid defect is something all ophthalmologists should be able to do, according to Robert A. Mazzoli, MD.

Upper eyelid defects are less common, and they are more challenging because of the dynamic movement of the eyelid and the lid’s function in protecting the cornea, noted Christine C. Nelson, MD. Repairs of these defects, she said, are more likely to be referred to an oculoplastics specialist (see “Upper Eyelid Issues”).

A number of specialties have staked a claim in eyelid reconstruction, including otolaryngologists and general plastic surgeons, but Dr. Mazzoli contends that ophthalmologists are best suited for the job. “Whether it’s a lid reconstruction for a tumor or for trauma, the ophthalmologist is the pro,” he said. “We’re the ones who know the anatomy, and we’re the ones who can repair the lids the best.”

Nailing Down the Diagnosis
A correct early diagnosis with complete removal of the eyelid tumor always takes precedence over cosmetic concerns. Identified early, most eyelid lesions have an excellent prognosis, said Daniel P. Schaefer, MD. He underscored the importance of being familiar with the clinical signs, presentation and appearance of malignant lesions in the periocular area and of having the diagnosis established before excising the lesion.

When to biopsy. Characteristic findings that require a biopsy are growth, ulceration, induration, pearly borders, irregular borders or asymmetry, telangiectasia, loss of the normal eyelid architecture (such as loss of eyelashes) and discoloration.

Technical concerns. Dr. Nelson agreed that eyelid lesions should be approached with a high index of suspicion, especially with the dramatic increase in malignant melanoma. “If you are concerned at all about melanoma, you should not do a shave biopsy,” she emphasized. “You want to take a full-thickness skin biopsy because the prognosis for melanoma is based on the depth. If you shave off the top half of the lesion, the prognosis for that patient is gone forever.”

Dr. Schaefer noted that the biopsy should include both normal and abnormal tissue, capturing the junction between the two to assist the pathologist in the diagnosis. Before Dr. Schaefer does a biopsy, he takes photographs and marks the lesion on the photograph to facilitate subsequent identification of the involved area. He hangs these photographs in the OR to refer to while he is doing the repair.

Surgical Essentials
Avoid surgical surprises. Dr. Mazzoli pointed out that planning for a lid reconstruction begins in the office. Because the reconstruction technique is determined in large part by the size of the defect, the surgeon needs to anticipate defect size and what type of repair may be involved.

“You have to be able to look at the lesion and say, ‘I’m going to need a skin graft.’ That’s a decision you have to make in the office. You can’t wait until you’re in the operating room, where you could end up with a surgical surprise.” Dr. Mazzoli recommends using the natural landmarks of the eye to estimate the size defect that will be created (see “Estimating Lesion Size”).

But lid laxity, especially in older patients, also comes into play when making the final selection of a reconstruction technique. In a patient who has a larger defect but who has ample lid stretch, you may be able to use a technique typically reserved for smaller defects.

“After I get clear margins, I take a forceps on each side and with gentle traction pull the two cut ends toward each other,” Dr. Mazzoli said. “The residual gap is what I have to fill in. If someone appears to have a big defect but has really loose tissue, you may surprise yourself at how much you are able to bring the two edges together.”

Excision options with nonmelanoma lesions are direct excision with frozen section control or a Mohs’ procedure, Dr. Nelson said. A Mohs’ procedure is typically performed by a specially trained dermatologist, who then sends the patient to the ophthalmologist for the subsequent reconstruction. With melanoma, she added, you can’t do frozen sections. You need permanent sections, and you may have to do the margins, wait several days for the permanent pathology and then excise the lesion or take more margins.

Reconstruction rationale. The goals of eyelid reconstruction are to re-establish a stable eyelid margin, provide adequate lid to protect the eye, minimize vertical tension on the lid, provide a smooth posterior surface and restore a good cosmetic appearance. Full-thickness defects are reconstructed in layers—tarsal plate and conjunctiva, orbicularis oculi muscle and skin.

Inviolable principles. “When you are replacing eyelid structures, you have to think about a blood supply, and you always want to have vascular tissue available to you,” said R. Patrick Yeatts, MD. “So you have to know where your blood supply is going to come from.” This consideration is the basis for another inviolable principle: Never use two free grafts together. If one layer is a free graft, the other layer has to be vascularized.

It’s also important to freshen the wound edges when performing a delayed reconstruction, as when a Mohs’ procedure was performed earlier by a dermatologist.

“Freshening the wound edges is a critical basic surgical technique that we don’t use a lot in ophthalmology and that ophthalmologists sometimes forget,” Dr. Nelson said. “I take a 15 blade and scrape off any fibrin and clot, make the wound rebleed and then cauterize it.”

Fix It: Small Defects
In general, a lid defect is considered to be small if it involves about 30 percent or less of the lid. A medium-sized defect involves about 30 percent to 50 percent of the lid, and a large defect has taken 50 percent or more. A very small defect—or a somewhat larger one in an older patient—generally can be repaired by direct closure, sewn in layers if it is full-thickness.

The first step is to align the borders, Dr. Mazzoli said. You put the landmarks back together on either side of the defect, approximating grayline to grayline, mucocutaneous border to mucocutaneous border, and lash border to lash border. This achieves an accurate alignment of the lid margin both vertically and anteroposteriorly and avoids any vertical step or notch or a forward bump. It also lines up the tarsus posteriorly, providing long-term stability of the repair.

A variety of sutures and suturing patterns can be used on the margins, and the choice depends on the surgeon’s preference. Reapproximating the tarsus, however, requires a substantial suture that won’t dissolve and fall apart before the tarsus can heal together. When repairing an upper lid, the tarsal sutures must be partial thickness to prevent corneal abrasion.

Fix It: Medium Defects
Larger defects that require only a small amount of extra tissue often can be closed directly by using adjacent tissue from the lateral canthus. When more tissue is needed, a semicircular rotational flap procedure can be performed.

Lateral canthotomy and cantholysis. A lateral canthotomy and cantholysis release the lid at the outer corner where it attaches to the orbital rim. These procedures can provide another 25 percent to 30 percent of horizontal length to close the defect, depending on patient age and tissue laxity, and they work equally well on lower and upper lids. In a canthotomy, the upper and lower lids are split with scissors at the lateral canthus. In some instances, this alone will provide sufficient relaxation. If not, severing the inferior limb of the canthal tendon will allow the lid to swing in closer to the other cut edge. Dr. Mazzoli noted that if a little more laxity is needed, sometimes you can make a back cut across the lower lid retractors and septum. The skin of the lateral canthus is closed with interrupted silk or absorbable sutures.

Semicircular rotational flap. A semicircular rotational flap (Tenzel procedure) may be used when additional tissue is needed or when a defect is bordering on 50 percent. Dr. Mazzoli described the Tenzel flap as a “very forgiving” procedure that works equally well in both lower and upper lid repairs.

The procedure allows you to borrow adjacent temporal tissue and rotate it in at the lateral side to provide enough laxity to close the defect. The diameter of the flap should be about twice that of the defect. In repairing lower lid defects, the semicircle starts at the lateral corner of the lid and curves superiorly and temporally—up toward the brow but avoiding the brow hairs.

“You need to have fairly good vertical height because as you stretch the flap it is going to flatten out,” Dr. Nelson said. “If you do a straight line out of the lateral canthus, the lid will sag laterally.”

The semicircular flap is widely undermined. Maximal rotational movement is achieved by performing a lateral canthotomy and severing the inferior limb of the lateral canthal tendon, the orbital septum and the retractors. The flap is then rotated in to provide a natural contour to the lid margin. The lid defect is closed primarily, as discussed, and the flap tissue is anchored to the periosteum of the lateral orbital rim to re-create the lateral canthus. The donor site is reapproximated with deep sutures.

Fix It: Large Defects
Lower lid lesions that involve more than 50 percent of the lid need to be reconstructed in layers, re-creating a posterior and an anterior lamella. Several procedures are available, but these repairs are often accomplished with a Hughes tarsoconjunctival flap reconstruction or a free tarsoconjunctival graft.

Hughes tarsoconjunctival flap. In the Hughes procedure, tarsus and conjunctiva are brought down from the upper eyelid like a window shade to form the posterior lamella, Dr. Yeatts explained. A skin-muscle flap or a skin graft is then used to cover the tarsoconjunctival pedicle. The Hughes procedure offers a good cosmetic and functional result. The downside is that it is a two-stage procedure that traditionally involves several weeks of ocular occlusion during healing. However, some oculoplastics surgeons are taking the flaps down sooner.

“Increasing evidence suggests that these flaps can be divided earlier,” Dr. Yeatts said. “It used to be said that you had to wait six to eight weeks, but people are dividing them earlier and earlier, and recent literature supports an earlier division.”

Flap size is determined by gently drawing the edges of the lower lid defect toward each other. The flap should be roughly the size of the residual defect.

With the upper lid everted on a Desmarres retractor, a horizontal incision slightly shorter than the length of the defect is made to the depth of the pretarsal space. A vertical cut extending to the top of the tarsal plate is made at each end of the horizontal incision, and the tarsus and conjunctiva are separated from Müller’s muscle and the upper lid retractors.

“Be sure to start the tarsoconjunctival flap at least 4 or 5 millimeters back from the upper lid margin, or you will get an entropion on the upper lid,” Dr. Nelson cautioned. “It’s tempting to start at the very edge because that is the closest. But you have to measure back and take the superior portion of the tarsal conjunctiva.” She added that if the surgeon isn’t meticulous in releasing Müller’s muscle, an upper lid retraction may develop.

After the flap is created, it is advanced down into the defect and sutured into place laterally and medially. An anterior lamella can then be re-created with a myocutaneous cheek flap that is rotated in from the side. The flap is sewn in place, lining up its upper border to create the new lower lid margin.

A myocutaneous flap is not recommended for patients with tight, nonelastic skin because of the possibility of an ectropion. Instead, a full-thickness skin graft can be taken from behind the ear or from the opposite upper lid.

The second stage of the Hughes procedure is performed after an adequate blood supply has been established and the flap has sufficiently healed. (Because cigarette smoking can interfere with these processes, patients should be advised to stop smoking before the procedure and to refrain from smoking during healing.) With a grooved dissector under the flap, the flap is separated with a scalpel or scissors angled so that the edge of the conjunctiva is slightly higher than that of the anterior edge. The extra conjunctiva can be draped forward to create a new lid margin.

Dr. Mazzoli noted that a similar procedure, known as a Cutler-Beard flap, can be performed for large upper eyelid defects. In this instance, a flap from the lower lid is advanced into the upper lid.

Free tarsoconjunctival grafts. Dr. Mazzoli pointed out that a free tissue graft may be preferable to a Hughes procedure in some patients. These would include individuals who are monocular and would experience significant functional impairment if their good eye was obscured with a flap for several weeks. Patients with glaucoma also would have difficulty with a Hughes flap procedure because of their need to instill their eye drops.

A free tissue graft requires a semirigid posterior lamella and an anterior lamella of muscle and skin. “For the posterior lamella, you could harvest tarsus and conjunctiva from the upper lid and bring it down as a free graft, or you could do the same from the other upper eyelid,” Dr.  Mazzoli said. “Other tarsal substitutes include ear cartilage, nasoseptal cartilage or hard palate.”

If a tarsal substitute is used for the posterior lamella, the anterior lamella must be vascularized. On a lower lid, that might mean advancing a cheek flap from below. The reverse also is true: If the anterior lamella is a free tissue graft, the posterior lamella must be vascularized.

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Upper Eyelid Issues

What about larger upper eyelid defects? Because these are technically more difficult, most upper lid reconstructions are referred out. “On the upper lid you have a lot more going on—blinking, a lot of movement, contour and lashes,” Dr. Nelson commented. “Reconstructing an upper lid requires meticulous and atraumatic management of the eyelid tissue because you need to have really good eyelid function and the repair has to be more aesthetically pleasing. Upper lid defects also can lead to corneal exposure and can threaten vision, and these issues may lead a general ophthalmologist to refer.”

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Estimating Lesion Size

Lesion size can be estimated by comparing the lesion to natural ocular landmarks, according to Dr. Mazzoli. He noted that the eyelid is about 28 to 30 mm side to side, and the corneal light reflex is seen at the 14- to 15-mm mark. “So if you have a tumor that extends from the lateral canthus to the corneal light reflex, you know you are going to have about a 50 percent defect.”

Similarly, the corneal diameter is about 12 mm, and a lesion that extends from limbus to limbus would then account for 12 mm out of the 28 to 30 mm of total eyelid—or a defect of about 40 percent to 50 percent.

That leaves about 30 percent of the eyelid on either side of the cornea. But because the distance from the medial limbus to the medial canthus is a little longer than that from the lateral limbus to the lateral canthus, Dr. Mazzoli apportions the lid into about 35 percent medially, 40 percent centrally and 25 percent laterally. Using these landmarks and percentages will give you a rough estimate of lesion size at any point on the lid.

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Meet the Experts

Christine C. Nelson, MD  Associate professor of ophthalmology at the University of Michigan, Ann Arbor.

Robert A. Mazzoli, MD  Chief and chairman of ophthalmology at Madigan Army Medical Center, Tacoma, Wash.

Daniel P. Schaefer, MD  Director of oculoplastic orbital reconstructive surgery, clinical professor of ophthalmology and associate professor of otolaryngology at the State University of New York, Buffalo.

R. Patrick Yeatts, MD  Professor and vice chairman of ophthalmology at Wake Forest University, Winston-Salem, N.C.