Since the incidence of single eyelids in Han population is 40.85%, double eyelid operation has become the most popular cosmetic procedure in China. In recent years, affected by the media, more and more younger people desire double eyelids, so that their eyes appear bigger and more alert.
According to the previous study of the anatomic microstructure of Asian people with double eyelids, there is fiber of the levator aponeurosis running through the orbicularis muscle layer and then attaching to the subcutaneous tissue of the eyelid skin.1 Asian people with single eyelids lack this fiber,2 so all kinds of double eyelid procedures aim to create it.
Although there are various kinds of procedures to perform double eyelids, how to obtain a natural and vivid double eyelid is still a problem. Most performed double eyelids along with some late complications, such as iatrogenic ptosis, bilateral asymmetry, depressed scar, sausage-like appearance, relapse, and so on.
To reduce the incidence of these complications, in our procedure we made some modifications. By simulating the anatomy structure of congenital double eyelids, we created natural and parallel double eyelids.
MATERIALS AND METHODS
From October 2012 to October 2018, 352 patients with 704 eyes underwent our procedure and followed up. The patients with congenital blepharoptosis or moderate/severe epicanthus were excluded through preoperative examinations. The average age was 24 years.
The preoperative design was performed with the patient in a supine position after the operative field was sterilely prepped and draped. While the patient's eyes closed lightly, gently pull the upper eyelid skin towards eyebrows, until the eyelashes were lightly everted. Then drew a line 7 to 8 mm distance parallel to the ciliary margin throughout the entire length. The medial point of the line starts from the vertical line of the lacrimal caruncle, and the lateral point ends up with the vertical line through the midpoint of the lateral canthus rahpe.
It is important to maintain the line parallel to the ciliary margin. As we all know, the contraction of the lateral and medial area of the levator aponeurosis is weaker than that of the midpupillary area. So, although the distance to the ciliary margin is the same, when people open their eyes, the excursion of the lateral and medial area of the crease still curves downward. If the design line of the lateral or medial area is lower, there will be pretaral skin sagging, which is prone to happen in the medial area (Fig. 1A).
Then gently pinched the skin above the incision line until the eyelashes were lightly everted, the skin pinched was marked for excision (Fig. 1B). Observation should be taken to ensure the symmetry of both creases, and modification would be performed depend on the position of the upper eyelids margin and the patient's desires.
Local anesthesia was administered by injecting 1.5 to 2 mL of 1% lidocaine with 1:100,000 epinephrine into the pretarsal skin subcutaneously each side. The incision was made through the whole thickness of the skin, and excess skin was resected with fine curved scissors. At this time, the subcutaneous tissue was exposed with some longitudinal microvessels walking through it (Fig. 1C).
At a 1 to 2 mm distance above the lower incision line, an ultrafine needle tip electrocautery was used to cut the subcutaneous tissue and orbicularis muscle open. Then a dissection between the orbicularis muscle and pretarsal fascia was performed using the ultrafine needle tip electrocautery until 1 mm away from the margins of eyelids, make sure not to injure the hair follicle of eyelashes. Pay attention not to impair the vessels in medial and lateral canthal areas, and preserve the longitudinal microvessels on the pretarsal fascia as far as possible (Fig. 2).
After obtaining the orbicularis myocutaneous flap, we started to deal with the orbital septum. First, resect the residual muscle and fascia from the superior border of the tarsus, and be careful not to injure the levator aponeurosis. Then, from the lowest site laterally, open the orbital septum transversely with a fine curve scissor parallel to the superior border of the tarsus. For patients who had an extremely droopy orbital septum, a moderate part of the septum tissue need to be resected parallel to the double eyelid line, and the excess fat herniated spontaneously should be removed. There we got a pearly white and reflective membrane flap composed of inferior orbital septum combining with the levator aponeurosis, which is quite dense and thick (Fig. 3).
The septal fat is contained within a thin and transparent membrane. Sometimes we found that there are fibrous connections between the posterior orbital septum and this membrane, which impedes the lifting movement of the levator aponeurosis. By cutting these fibers, the load of the levator aponeurosis is reduced, and it would be easier and quicker for patients to open their eyes.
Then, the superior margin of pretarsal orbicularis muscle was sutured to the inferior margin of levator aponeurosis interruptedly with 7–0 nylon suture. The first suture was placed on the midpupillary point, and the second was next to it in the medial, the third was next to it in the lateral (Fig. 4).
The patient was asked to open her/his eyes after each stitch to observe the arc of the crease and made sure the eyelids margin site cover 1 mm of the corneas (Fig. 5A).
If the appearance was unsatisfied, we adjusted the suture site of the orbicularis muscle or the thickness of orbicularis myocutaneous flap to gain symmetry and smooth double eyelids.
When this step completed, the skin margins of the lower and upper incisions were closed by their own, and 7–0 nylon suture was used to close it without any tension.
Appropriate use of ice packs in first 48 hours post-operative was helpful in reducing edema. The patient was asked to remove dressing and clean incisions with saline solution on the second day. All the patients were followed up for 6 to 30 months.
A total of 352 patients with 704 eyes were operated on by one senior surgeon from October 2012 to October 2018. The follow up was performed by 2 surgeons simultaneously from 6 to 30 months after operation to evaluate the long-term results (Supplemental Digital Content, Table 1, http://links.lww.com/SCS/A927).
There were 29 patients (8.2%) that showed slight asymmetry, and 7 eyes (2.0%) showed shallow creases. Besides that, all the creases were smooth and natural, just like congenital supratarsal fold, when opening eyes, there was no sausage-like appearance, and when closing eyes, there were no depressed scars.
Among the 29 patients with slight asymmetry creases, there were 8 patients who underwent revision operations with our procedure, and the results were satisfying. Since other patients’ double eyelids’ asymmetry was not obvious, the revision operations were not required. The patients with shallow creases in 7 eyes all underwent revision operations.
The asymmetry of creases is the main complication in our procedure, because unlike traditional procedure, the double eyelid we performed is a dynamic structure. So, the height of crease is decided not only by the incision height, but also by some other factors, such as the thickness of the orbicular muscle, the suture position of orbicular muscle and levator aponeurosis, the residual length of the orbicular septum, and so on. In order to avoid this complication, after each suture, the patient was asked to open eyes to make sure the eyelids margin cover 1 mm of the corneas. And the 2 eyes sutured simultaneously are also important. As we can see in Table S1, the incidence rate of asymmetry double eyelids declined from 2012 to 2018. Therefore, the proficiency of this procedure can reduce this complication.
The complication of shallow creases happened in the prophase of our procedure.
During the revision operation of this complication, we found that it tended to occur in the patients with droopy orbital septum. Accordingly, for these patients, the residual orbital septum was trimmed moderately parallel to the double eyelid. And this complication has rarely occurred since then, but the long-term results still need to be assessed.
Besides that, all the patients showed symmetry, parallel and natural double eyelids, when opening eyes there was no sausage-like appearance, and when closing eyes there were no depressed scars (Fig. 5B and C).
Double eyelid operation is a common cosmetic procedure. There are various procedures.4,5,6,7 Accordance between operative double eyelids and congenital double eyelids should be subject to the anatomical structure.
By using the scanning of electron microscope and observing the microstructure of upper eyelid of Asians, it can be found that as for people with double eyelids, the levator aponeurosis fiber passes through the intermuscular septum of the orbicularis muscle and ends in the subcutaneous tissue. Single eyelids people diverge greatly, as their cross section shows that fibrous structure is absent and there is no bundle of fiber passing through the muscle and no fibrous structure in the intermuscular septum.3 So, all kinds of double eyelids procedures aim to create the fibrous connection between skin and levator aponeurosis to form double eyelids.
In traditional double eyelid operations, the pretarsal orbicular muscle is over resected in order to adhere the skin to the pretarsal tissue to created double eyelids. So, when people close their eyes, the creases are depressed. Besides that, because the tarsus is a static anatomical structure and cannot move along with eyes’ movement, the double eyelids are artificial obviously.
Therefore, to obtain a natural and dynamic supratarsal crease, there were some modifications to the traditional blepharoplasty procedures.4,5,6 These procedures fixing the pretarsal skin to the levator aponeurosis aim to simulate the anatomy structure of congenital double eyelids, so the double eyelids are more dynamic and natural. However, the contact area between the pretarsal skin and levator aponeurosis is narrow, which is one reason for the relapse of double eyelids.
So in our procedure, we made some modifications. First of all, we dissected the orbicularis muscle from the pretarsal fascia without excision of any orbicularis muscle. Kakizaki found the orbicularis muscle and skin of double-eyelids at the crease are thinner than those of single eyelids.8 Therefore, some surgeons propose that a strip of orbicularis muscle and preseptal tissue should be removed to obtain a finer upper eyelid fold.5,6 Instead of that, we dissect the orbicularis myocutaneous flap from the pretarsal fascia, then pull it cephalad to suture to the levator aponeurosis. By this step, the stretch of skin and orbicularis muscle makes them thinner, especially when people open eyes. For people with thick soft tissue, this step can make the double eyelids agiler, and the sausage-like appearance is avoided.
Furthermore, unlike most procedure which sutures the levator aponeurosis to the pretarsal skin,4,5,6 we suture the levator aponeurosis to the orbicularis muscle. Under the electron microscope, as for people with double eyelids, the levator aponeurosis fiber passes through orbicularis muscle and ends in the subcutaneous tissue.3 So, in our procedure, we reconstructed this physiological structure by suturing the levator aponeurosis to the orbicularis muscle. Since the levator aponeurosis and orbicularis muscle are both dynamic anatomical structures, it can move along with the movement of the palpebral fissures to form dynamic double eyelids.7 And meanwhile the contact area of orbicularis muscle is wider than that of the pretarsal skin, so the adhesion is firmer, and the relapse rate is reduced.
Otherwise, during the procedure, we used ultrafine needle tip electrocautery to cut and dissect tissue, which brought about negligible bleeding and a clear vision of the operative field, and was favorable for identification and dissection of different tissues. It not only can make smaller damage to tissue but also can preserve vascular net of tissues, which can minimize bleeding in the operative field and reduce the recovery time post-operatively.
In conclusion, relative to the traditional double eyelid operations, our procedure reconstructed the physiological structure of double eyelids, which can avoid some traditional complications, such as depressed scar, sausage-like appearance; meanwhile, the obtained double eyelids are more natural and vivid than before.
While there are still some complications in our procedure: asymmetry and shallow creases. The former one can be overcome by the experienced surgeon by modifying the suture position according to the location of eyelids margin. The latter one tended to occur in the patients with a droopy orbital septum, and trimming the residual orbital septum would be helpful.
By reconstructing the physiological structure of upper eyelids, our procedure creates dynamic, parallel and natural double eyelids, which are accordant with the congenital double eyelids both in appearance and movement.