Transconjunctival Lower Blepharoplasty: Key Technique for Patients with Small Lid
Transconjunctival Lower Blepharoplasty is a surgical procedure designed to improve the appearance of the lower eyelids by removing excess fat and addressing issues such as puffiness or bags under the eyes. This cosmetic surgery technique is primarily employed to create a more youthful and refreshed look in individuals with lower eyelid concerns, without leaving visible external scars.
Unlike traditional lower blepharoplasty, which often involves an external incision just below the eyelashes, the transconjunctival approach is performed from the inside of the lower eyelid. This means that no external incisions are made on the skin, leading to inconspicuous scarring. Transconjunctival lower blepharoplasty primarily focuses on addressing the accumulation of excess fat in the lower eyelids. The surgeon carefully removes or redistributes the fat to eliminate puffiness and bags under the eyes. By working through the inner lining of the lower eyelid, there's no need to cut through the skin, making it a minimally invasive technique. In cases where there is excess skin as well as fat, the traditional lower blepharoplasty approach may be more appropriate, as it allows for the removal of surplus skin. Transconjunctival blepharoplasty, however, does not involve skin excision and is better suited for individuals with good skin elasticity.
Understanding the Anatomy
Before delving into the organization of the periorbital soft tissues, it is crucial to establish a grasp of the dimensions of the bony orbit and its contents. Generally, the bony orbit assumes a conical shape, with dimensions that typically encompass a depth ranging from 38 to 44 mm, a height ranging from 33 to 37 mm, and a width spanning from 38 to 41 mm. On average, the internal volume of the orbit is approximately 30 cc, housing three primary structures: the globe (10 cc), extraocular muscles (10 cc), and orbital fat and lacrimal gland (10 cc).
Of particular significance in the context of lower blepharoplasty is the organization of periorbital fat. Postseptal orbital fat is categorized into five discrete pads, comprising two upper and three lower pads. Concerning the three lower fat pads, they consist of a lateral, middle, and medial fat pad. Notably, the middle and medial fat pads are connected by a narrow isthmus of fat and are separated by the inferior oblique muscle.
Furthermore, orbital fat is unevenly distributed within the orbit, with a significant portion located in posterior, supraperiosteal pockets between intramuscular septae. In fact, approximately 60% to 70% of the fat volume is situated deep within the bony orbit, posterior to the globe. Consequently, the posterior orbital fat has limited impact on vertical globe support, a role primarily attributed to the aforementioned orbital fat pads. This concept holds great significance, as even the removal of a small amount of orbital fat from the anterior areas, immediately deep to the orbital septum, can profoundly affect the position of the globe. In 1986, Manson demonstrated that the removal of just 0.5 cc (equivalent to a pea-sized volume) of orbital fat caused the globe to shift 1 mm inferiorly and 2 mm posteriorly.
With the foundational knowledge of the bony orbit's contents in place, we can now explore the organization of the periorbital soft tissues. The periorbital soft tissues of the eyelid are delineated in layered terms, with an anterior and a posterior lamella separated by the orbital septum. Moving from superficial to deep, the anterior lamella consists of skin, subcutaneous adipose tissue (referred to as malar fat), and the orbicularis muscle. This orbicularis muscle is subdivided into three distinct components: pretarsal orbicularis (overlying the inferior tarsal plate), preseptal orbicularis (overlying the orbital septum), and preorbital orbicularis (overlying the facial bones). The fibrous attachment of the orbicularis is located at the lateral orbital rim, specifically at a discrete fibrous structure known as the lateral thickening. Extending medially from the lateral thickening, along the inferior rim, is another crucial ligament called the orbicular retaining ligament (ORL), which attaches the orbicularis muscle to the zygomatic bone. Understanding the function and location of this structure is fundamental to comprehending the pathophysiology of lower lid aging, a topic that will be addressed later. Immediately beneath the orbicularis muscle lies the orbital septum, which serves to separate the anterior and posterior lamellae. As for the posterior lamellae, it comprises the inferior tarsus and palpebral conjunctiva.
Having grasped the layered organization of the periorbital soft tissues, we can now delve into a pivotal component of the globe's support system, the Lateral Canthal Tendon (LCT). The LCT plays a dual role, primarily offering lateral anchorage for the eyelids and, secondarily, providing vertical support for the globe and lower lid. The bony attachment of the LCT is situated at Whitnall tubercle, positioned approximately 4 mm posterior to the lateral orbital rim on the lateral orbital wall. It is from this point that the LCT extends inferomedially, attaching to the lateral aspects of the upper and lower tarsal plates. Furthermore, the LCT is positioned 2 to 3 mm superior to the medial canthal tendon, contributing to the formation of a 2 to 3 tilted intercanthal axis, a desirable characteristic.
Lower Eyelid Aging
Lower eyelid aging, akin to various physiological processes, stems from intricate cause-and-effect relationships. The cumulative impact of these relationships manifests in well-documented and frequently observed physical manifestations. This section delves into the precise origins of several common physical examination findings commonly associated with aged lower eyelids. This knowledge equips the surgeon to pinpoint the source of a patient's primary concerns, thereby enhancing the prospects of achieving a successful outcome.
The anatomical discussion of lower-lid changes initiates with an assessment of the external appearance of the aging lower eyelid. One of the most prevalent findings often described as "puffy eyelids" occurs as the lidecheek junction merges with the tear trough. This fusion results in a continuous furrow that demarcates the displacement or pseudoherniation of postseptal fat from the inferiorly displaced and sagging suborbicularis oculi fat (SOOF) pad. These anatomical shifts culminate in the formation of lower lid bags, indicative of herniated or, more commonly, pseudoherniated postseptal fat.
Regarding the surface appearance of the lateral lower eyelid, noteworthy changes include the presence of fine rhytids and crow's feet extending from the lateral canthus. These changes frequently result from ultraviolet (UV) damage compounded by age-related collagen remodeling decline. In addition to the development of fine rhytids and crow's feet, the lateral canthal angle assumes a more rounded contour with age, chiefly attributable to increased laxity of the lateral canthal tendon (LCT). This process leads to the loss of the aesthetic, almond-shaped palpebral aperture, ectropion, increased scleral show, and a pronounced accentuation of lower lid rhytids.
Each of the aforementioned physical findings is interconnected with their etiologies. The aging process of the lower lid is a chain reaction, commencing with the progressive laxity of the globe's support apparatus, primarily consisting of the Lockwood suspensory ligament (LL) and the LCT. This results in the descent and posterior translation of the globe, causing postseptal fat to displace anteriorly, leading to bulging or pseudoherniation through the orbital septum. This process accounts for both lower lid bags and sunken eyes. Furthermore, increased laxity of the LCT and LL not only displaces the globe and postseptal fat but also leads to the shortening of the palpebral aperture, ectropion, and accentuated rhytids.
As mentioned earlier, the age-induced development of LCT and LL laxity initiates a series of events that result in various unaesthetic changes in periorbital soft tissues. One of the more distressing changes is the development of the aforementioned lower lid bag, causing dark circles due to shadowing. The majority of the infraorbital bulge is attributed to displaced postseptal fat that protrudes anteriorly, with the inferior boundary of the bulge held in place by the orbicular retaining ligament (ORL), defining the crucial lidecheek junction.
Adjacent to the lidecheek junction lies another common age-related lower lid anomaly, the tear trough deformity. Unlike the lidecheek junction, this deformity does not originate from increased LCT laxity. Instead, it results from the descent of the malar fat pad and the exposure of a triangular intermuscular depression bordered by the levator palpebrae superioris, levator palpebrae superioris alequae nasae, and the orbicularis muscles.
Lastly, as individuals age, the orbital fat pads do not expand in volume; there is even a tendency for lipoatrophy, implying that the characteristic infraorbital fat bags associated with aging are not caused by an increase in adipose volume. These changes primarily result from shifts in globe position and periorbital fat distribution. This understanding is pivotal when devising a treatment plan for patients with lower eyelid fat pseudoherniation, a condition that responds well to fat repositioning.
Indication
One specific indication pertains to patients presenting with pseudoherniated fat, mild to moderate skin laxity, and minimal redundancy of the orbicularis muscle. Nevertheless, it's crucial to note that these indications are not inflexible. Indeed, the transcutaneous approach can be combined with complementary procedures such as skin pinch and lateral canthopexy, thus rendering it a versatile and adaptable technique.
Advantages and Disadvantages Having covered the surgical anatomy of the orbit, the pathophysiology of aging, and the indications for use, we are now better equipped to assess the merits and drawbacks of transconjunctival lower blepharoplasty.
Let us begin by addressing the multitude of advantages associated with this technique. Foremost among these advantages is the substantial reduction in the incidence of a major complication commonly encountered in transcutaneous lower blepharoplasties, namely ectropion. By confining the incision to the conjunctiva and circumventing the dissection of the delicate anterior lamella, the risk of scar contracture of the lower lid is significantly minimized. Additionally, the transconjunctival approach eliminates visible scarring, which is a notable aesthetic benefit.
In most instances, the advantages of the transconjunctival approach far outweigh the disadvantages. However, it is essential to acknowledge that this may not be universally applicable. For instance, patients exhibiting pronounced lid laxity may necessitate a transcutaneous approach involving skin and muscle resection. Another limitation of the transconjunctival approach is the heightened level of technical proficiency required for its execution.
source: Transconjunctival Lower Blepharoplasty With and Without Fat Repositioning (2018)
The Technique
Due to its exceptional versatility, transconjunctival fat repositioning has emerged as one of the most frequently employed techniques in lower blepharoplasty. This approach is aptly indicated for patients presenting with lower lid bags and minimal-to-moderate skin laxity. Another common observation is the presence of a conspicuous lidecheek junction/lower lid bag, which can be effectively addressed through this procedure either on its own or in combination with a midface lift.
Following intubation, the lower lid is gently drawn forward using a 5-0 prolene tarsal stitch. In this position, approximately 3 cc of 1% lidocaine with 1:100,000 epinephrine is administered within the subconjunctival and subcutaneous planes near the lateral canthal tendon (LCT). Subsequently, a standard lateral canthotomy is performed.
At this juncture, an incision is made in the conjunctiva, positioned 1 to 2 mm inferior to the tarsal plate, utilizing bovie electrocautery. This incision extends medially along the length of the lower lid, terminating 5 mm lateral to the medial punctum. The incision penetrates to a superficial depth, just above the orbital septum, revealing the orbicularis muscle at the depth of the incision. Once the orbicularis is exposed along the length of the incision, a subperiosteal plane is meticulously developed downward to the inferior orbital rim. At the level of the orbital rim, specifically the arcus marginalis, the arcus is incised using bovie, reaching the level of the orbital rim. This dissection is then continued subperiosteally, maintaining a 5 mm distance beneath the arcus marginalis. This effectively severs the ligamentous attachment of the orbicularis oculi muscle to the midfacial skeletal structure. At the same level, this dissection is extended medially into the tear trough. These precise steps are of paramount importance, as they establish the pocket within which the periorbital fat will be repositioned.
At this stage, the repositioning of pseudoherniated orbital fat over the inferior orbital rim and into the previously dissected subperiosteal pocket can commence. The orbital fat is meticulously teased out over the rim using a curved hemostat. Subsequently, a 5-0 vicryl suture, affixed to a tapered P-3 needle, is employed to secure the fat to the periosteum at the depth of the subperiosteal dissection, situated below the attachment of the arcus and extending into the tear trough deformity. This technique effectively harmonizes the lidecheek junction. Finally, closure is executed through the use of four interrupted 6-0 fast-absorbable gut sutures within the palpebral conjunctiva.
Prophylactic lateral canthopexy is nearly always integrated into the lower blepharoplasty procedure. This simple and expeditious adjunct, which involves the superior repositioning of the LCT, enhances globe support and tightens the skin of the lower lid. To initiate this phase of the procedure, toothed tissue forceps are employed to grasp the common limb of the LCT, which had been lysed during the initial steps of the procedure. A 5-0 nylon suture is then passed through the tendon twice, in the same direction, with the needle left attached. Subsequently, the LCT is securely affixed to the periosteum of the lateral orbital rim using the same nonresorbable suture. The positioning of the LCT 2 mm higher than ideal is substantial to account for potential relapse. The closure process is concluded with interrupted 5-0 prolene sutures for the skin, and the grey line is meticulously reapproximated with 6-0 fast-absorbable sutures.
Complications
Adhering to the conservative approach of transconjunctival lower blepharoplasty, there are relatively few complications specific to this procedure. As previously mentioned, a significant advantage of this method is the reduced occurrence of complications, including lid malposition, external scarring, canthal webbing, wound dehiscence, and, most notably, ectropion. However, it is noteworthy that, similar to the transcutaneous approach, the risk of the most severe complication, retrobulbar hematoma, is exceptionally rare.
Reference:
Transconjunctival Lower Blepharoplasty (2016)
Anatomy, pathophysiology, and prevention of senile enopohtalmia and associated herniated lower eyelid fat pads (1997)
The aging eye: pathophysiology and management (1997)
Transconjunctival versus subciliary approach for orbital fracture repair–an anthropometric evaluation of 221 cases (2013)
Transconjunctival orbital fat repositioning: transposition of orbital fat pedicles into a subperiosteal pocket (2000)
Transconjunctival Lower Blepharoplasty With and Without Fat Repositioning (2018)
Discover the Science behind Asian Blepharoplasty
in our upcoming Mini Fellowship happening globally:
IFAAS Mini Visiting Fellowship (Observation)
Korean Advanced Facial Aesthetic Surgeries - Advanced Asian Blepharoplasty
Mar 18-19, 2024 - Seoul, South Korea - [Register Now]
May 3-4, 2024 - Singapore - [Register Now]
More Upcoming Global Events