11 Lower Eyelid Blepharoplasty
As essentially all lower lid blepharoplasty procedures are performed for cosmetic reasons, the most important aspect of the preoperative evaluation is to ask the patient what characteristics of their lower lid appearance they wish to change. If “baggy lids” are of concern, then certainly herniating orbital fat removal will be the principal goal of surgery. If the patient is not concerned about skin wrinkling, then a transconjunctival approach can be considered. If a transcutaneous approach is selected, then there is little reason to risk complication by trying to remove too much skin. Be wary of the patient who expects unrealistic social or occupational rewards from the surgery.
With the use of a mirror, one can show the patient what can be expected from skin removal, by pulling down on the cheek to smooth the skin, to approximate the postoperative appearance.
The first physical finding to be evaluated in the lower lid is the presence or absence of fat herniation. Look at the patient from the front and side, make a simple sketch of the three fat pockets, and grade the amount of herniation from 1 to 4. Gentle pressure against the globe through the upper eyelid will give an indication of orbital septum tautness to predict whether more fat will herniate forward once the septum is opened.
The next characteristic to evaluate is the amount of excess skin present. Assess the amount of wrinkles present and pull down gently on the cheek skin to approximate the amount of skin that can be removed without displacing the eyelid.
It is important to evaluate the horizontal tone of the lower lid, especially if the skin is to be removed. A “snap test” is performed in which the lower lid is pulled downward with the thumb and released without the patient blinking. If the lid snaps back against the globe, the tone is very good. This will allow a prudently aggressive approach to skin removal. If it moves back slowly to its original position, then fair tone exists and judicious skin removal should be exercised. The patient should be advised before surgery of the need for conservatism and its effect on skin removal. If the lid does not return to its normal position until the patient blinks, then the tone is poor and horizontal shortening of the eyelid should be combined with skin removal, or a transconjunctival approach should be used. The lateral canthal tarsal strip method of tightening the lid is preferred (see Chapter 7).
It is also important to evaluate the contour of the orbicularis in the lower eyelid. If the patient has redundancy of the pretarsal orbicularis, usually noticeable upon smiling, then a strip of the redundant muscle can be excised prior to skin closure. If excess rolls of orbicularis are present along the infraorbital rim, the so-called orbicularis festoon, then a redundant strip of preseptal orbicularis can be excised.
A patient’s blinking dynamic and lid closure status is also evaluated. Tear film breakup time and results of the Schirmer test are recorded.
Preoperative photographs of the eyelids should be taken. They serve not only as part of the medical record, but patients enjoy looking at them several months later.
A thorough medical history and appropriate physical examination for the type of anesthesia should be obtained. Aspirin intake should be discontinued 2 to 4 weeks before surgery. If a patient uses certain antidepressants, such as tranylcypromine (Parnate) or phenelzine (Nardil), then the use of epinephrine and some sedatives may be contraindicated.
Finally, there should be a thorough discussion of the surgery, type of anesthesia (usually local with mild sedation), and postoperative care, including ecchymosis and swelling.
As this is aesthetic surgery, the basic indication is a cosmetically significant excess of lower lid skin or fat herniation that is surgically correctable. Since lower lid blepharoplasty procedures should not be repeated frequently, surgery should result in enough of an improvement to be beneficial to the patient. The surgeon should have good rapport with the patient, and the patient should have a good understanding of what to expect from the surgery.
Patients with significant excess skin and redundant orbicularis are best treated with a transcutaneous approach. The transconjunctival approach is best utilized when there is little or no need to excise skin, a visible scar is very undesirable (as in young male), and the lid is lax enough to permit surgical exposure. This approach requires the surgeon to have more familiarity with eyelid anatomy. This is also a good approach as a reoperative procedure to remove residual fat.
There are several important points to remember about the lower eyelid anatomy during blepharoplasty.
The pretarsal orbicularis is responsible for lid apposition and blink. Preservation of as much of its function as possible is desirable. Care should be taken not to excise too much muscle or to separate the muscle from its nerve supply.
The orbicularis, particularly the preseptal orbicularis, can become redundant along with the skin and, therefore, should be excised. Marked redundancy of the orbicularis along the infralateral orbital rim is referred to as festoons.
The retractors of the lower eyelid consist of the capsulopalpebral fascia and Müller’s muscle. The capsulopalpebral fascia begins as the capsulopalpebral head, with fine fibrous connections to the inferior rectus muscle and tendon. The capsulopalpebral head divides into two portions as it extends around and fuses with the sheath of the inferior oblique muscle. Anterior to the inferior oblique muscle, these two branches rejoin to form the Lockwood’s ligament. The fascial tissue anterior to the Lockwood’s ligament is the capsulopalpebral fascia. A large portion of the capsulopalpebral fascia ascends the lower eyelid to insert onto the inferior margin of the tarsal plate. The inferior oblique muscle originates from behind the posterior lacrimal crest, several millimeters behind the orbital rim. It can be damaged during lower eyelid blepharoplasty, particularly the transconjunctival approach.
Because the orbital septum is attached to the inferior orbital rim, an adhesion between the cut edge of the septum and the movable portion of the lid could result in downward tethering of the lid.
Appropriate oral or injectable sedatives may be given before injection of the local anesthetic. The patient must be reasonably alert to cooperate in assessing the amount of skin for removal.
A mixture of 6 ml of lidocaine with 1:100,000 epinephrine plus 3 ml of plain lidocaine plus 1 ml of 8.4% sodium bicarbonate gives effective local anesthesia and vasoconstriction. The 1:166,000 dilution of epinephrine concentration avoids overconstriction of blood vessels, which can result in rebound dilation after surgery and postoperative bleeding. After placing a drop of topical proparacaine in the cul-de-sac, an infraorbital nerve block may be given. This is accomplished by transconjunctival injecting over the infraorbital foramen, located about 1 cm below the midinferior orbital rim. A small amount of anesthetic is also injected along the preseptal and infraciliary region of the lid. Gentle pressure at this point minimizes hematoma formation. Since epinephrine takes 8 to 10 minutes to take effect, the incision should be delayed appropriately. The patient is then prepared and draped. It is essential that surgical drapes do not distort the facial skin, which can result in an overestimation or underestimation of the amount of skin removal. Slight reverse Trendelenburg positioning is preferred to minimize orbital venous pressure and to more closely approximate the effect of gravity on the cheeks.