Paralytic lagophthalmos: gold-weight implantation.

An important aspect of the management of patients with facial paralysis is the rehabilitation of the paralyzed periocular area. Failure to rehabilitate this area can result in exposure keratitis, corneal ulceration, and even blindness.

Medical therapy consists primarily of ocular protectants (e.g., lubricants), eyelid taping, and use of a moisture chamber. Although these modalities are effective, they are often poorly tolerated. The most commonly used method of surgical correction of paralytic lagophthalmos is gold-weight lid loading (figure). This procedure has been proven to be safe and effective for the long-term management of the paralyzed eyelid, and it is preferable to tarsorrhaphy, which is associated with a poor cosmetic outcome and a limited visual field.

Jobe first suggested the placement of a gold weight into the upper eyelid to assist closure by counteracting the normal levator muscle retraction. (1) The use of 99.9% pure 24K gold helps prevent foreign-body reactions. The gold implant is shaped into a thin, curved plate that fits the curvature of the cornea. Each implant is punched with holes that allow for suture fixation and fibrous ingrowth. Reported complications of gold-weight implantation include implant migration or extrusion, wound infection, failure to correct the lagophthalmos, and excessive postoperative ptosis, but these problems are rare. (2-4) Complications can be minimized by proper surgical technique and a good understanding of periocular anatomy. Gold-weight lid loading is easily reversible.

An interesting new concept in lid loading was suggested by Berghaus et al in 2003. (5) They reported that a platinum chain may be superior to a gold weight in several ways. For example, a platinum implant can be smaller than a gold implant because platinum is more dense than gold (21.5 vs. 19.4 g/[cm.sup.3]). Also, the flexible nature of a chain allows for better alignment of the implant with the contour of the tarsal plate. Finally, when platinum implants were removed and examined histologically after facial nerve function had been restored, the peri-implant capsules showed less inflammation than the capsules around typical gold implants.

Regardless, a gold weight can be safely implanted in an outpatient setting with local anesthesia (general anesthesia may be induced if necessary). The surgery can be performed as a stand-alone procedure or at the time of parotidectomy or temporal bone surgery when facial nerve function has been compromised. It can also be performed in conjunction with a lower-lid-tightening procedure.

Preoperative photographs should be taken of all patients to document the lagophthalmos. The weight of gold implants ranges from 0.6 to 1.6 g. The weight of an implant for a given patient is determined by testing different weights; this is accomplished by adhering different weights to the upper eyelid with Steri-Strips or a benzoin adhesive. When choosing a weight, the surgeon must consider the balance between the amount of corneal protection afforded by eyelid closure and the degree of visual-field obstruction caused by ptosis at rest. The authors usually use a 1.2-g implant (MedDev Corp.; Sunnyvale, Calif.).

Presurgical marking of the supraciliary crease (often 9 to 10 mm above the eyelashes) and the midpupillary line are imperative for accurate placement. Anesthesia is induced with a subcutaneous injection of 1% lidocaine with epinephrine 1:100,000. The eyelid is prepped and draped in sterile fashion. Some surgeons prefer to place a corneal shield prior to injection.

A 1.5-cm incision is made in the supraciliary crease. Blunt dissection is carried deep to the orbicularis oculi muscle to the tarsal plate. Special attention is paid to staying at least 2 mm superior to the lid margin and centered just medial to the midpupillary position. Dissection below the superior margin of the tarsus should be emphasized because this is the primary insertion point of the levator muscle. (6) A "precise pocket" is created that is approximately the size of the implant and positioned 2 mm medial to the midpupillary line. If awake, the patient may assist by simulating eyelid closure. The weight should be placed inferior to the levator insertion on the tarsal plate, deep to the orbicularis oculi, and superficial to the tarsal plate. Muller's muscle, which is deep to the levator muscle, should not be violated during dissection. The implant is secured to the tarsus with two partial-thickness sutures of 6-0 clear polypropylene or Vicryl.

The orbicularis oculi is closed over the implant with absorbable 6-0 Vicryl suture, and the skin is carefully approximated with 6-0 nylon or fast-absorbing gut. For 24 hours postoperatively, the patient's head should remain elevated and ice packs should be applied to the eyelid. Ophthalmic antibiotic ointment is applied for 3 days postoperatively.

References

(1.) Jobe RP. Atechnique for lid loading in the management of the lagophthalmos of facial palsy. Plast Reconstr Surg 1974;53:29-32.

(2.) Kao CH, Moe KS. Retrograde weight implantation for correction of lagophthalmos. Laryngoscope 2004;114:1570-5.

(3.) Snyder MC, Johnson PJ, Moore GE Ogren FR Early versus late gold weight implantation for rehabilitation of the paralyzed eyelid. Laryngoscope 2001;111:2109-13.

(4.) May M. Prospective evaluation of eyelid function with gold weight implant and lower eyelid shortening for facial paralysis. Arch Facial Plast Surg 2002;4:60-1.

(5.) Berghaus A, Neumann K, Schrom T. The platinum chain: A new upper-lid implant for facial palsy. Arch Facial Plast Surg 2003;5: 166-70.

(6.)Kartush JM, Linstrom C J, McCann PM, Graham MD. Early gold weight eyelid implantation for facial paralysis. Otolaryngol Head Neck Surg 1990;103:1016-23.