Why Simultaneous Surgery of Under-Eye Fat Repositioning and Lateral Canthoplasty is Advantageous When Using Conjunctival Incision Method (Explanation by Plastic Surgery Specialist)
Author: Director Lee Won (Plastic Surgery Specialist: Representative Director of 21plastic surgery)
This content has been written in compliance with relevant laws including the Medical Practice Act.
Together or Separate? Here's the Conclusion First
To put it simply, if it's under-eye fat repositioning using the conjunctival incision method, performing it simultaneously with lateral canthoplasty can be advantageous in many ways.
Both surgeries are performed in the lower eyelid area, and their incision approach sites are adjacent to each other. A clinical study published in Archives of Aesthetic Plastic Surgery analyzed 59 Asian patients who underwent both conjunctival incision under-eye fat repositioning and lateral canthoplasty (outer canthus plastic surgery), concluding that simultaneous surgery is a safe, effective method that can maximize aesthetic results and patient satisfaction. In particular, the study reported that the outer canthus incision for lateral canthoplasty also served as a pathway to secure the surgical field for the conjunctival incision approach.
Simply put, the conjunctival incision method approaches through the eyelid's inner mucosa without touching the outer skin. When the lateral canthoplasty incision naturally connects with this approach, both objectives can be addressed in a single surgery without the burden of additional incisions.
However, since eyelid laxity, skin redundancy, and eye corner structure vary from person to person, the decision to perform simultaneous surgery must be made following individual evaluation.
Mini Q&A
Q. Why is the condition "if using the conjunctival incision method" attached?
Among lower eyelid surgeries, the skin incision method handles both the skin and muscle layer together, so there are more variables to consider for simultaneous surgery. In contrast, the conjunctival incision approach from inside the eye preserves external tissues, so the burden of combining with lateral canthoplasty is relatively lighter. This will be explained in detail below.
What Both Surgeries Do Under the Eye
| Classification | Under-Eye Fat Repositioning (Conjunctival Incision) | Lateral Canthoplasty (Lower Outer Canthus Plastic Surgery) |
|---|---|---|
| Primary Purpose | Move orbital fat toward the tear trough to simultaneously improve bulging and hollowing | Open the area below the eye corner to expand horizontal and vertical eye width |
| Incision Location | Conjunctiva inside the eyelid (no outer skin incision) | Conjunctival incision and outer eye corner |
| Visible Scarring | None | Hidden along the eye corner wrinkle line |
| Surgical Area | Inside lower eyelid | Inside and outer side of lower eyelid |
As shown in the table, the incision sites of both surgeries are adjacent regions in the lower eyelid. This structural characteristic is the starting point of the simultaneous surgery advantage.
Advantages of Simultaneous Conjunctival Incision + Lateral Canthoplasty Surgery
1. Incision approaches are shared.
In the previously cited study, the outer canthus incision (lateral canthoplasty incision) was utilized as a pathway to broaden the surgical field that might be limited with the conjunctival incision approach alone. The researchers reported that this enabled more accurate correction of under-eye fat problems. Since the incisions complement each other structurally, there is no burden of opening the same area twice as there would be with two separate surgeries.
2. No scarring remains on the outer skin.
Conjunctival incision is performed inside the eyelid, and the lateral canthoplasty incision is hidden along the eye corner wrinkle line. In the cited study, no complications related to visible wounds were reported.
3. Low risk of ectropion.
According to PMC/NIH clinical data, the conjunctival incision approach does not touch the palpebral septum and anterior lamella (skin and muscle layer), so the postoperative ectropion incidence rate is reported to be lower. Lower eyelid ectropion, the most concerning postoperative complication, is mainly caused by vertical shortening of the anterior lamella from excessive skin removal, but conjunctival incision preserves this layer.
4. Recovery can be consolidated into one period.
One anesthesia, one swelling and bruising period. Since the recovery processes of both surgeries overlap considerably in the same area, you don't need to experience recovery periods twice as you would with separate procedures.
5. Eye contour ratio is completed within one plan.
Since lower eye refinement (fat repositioning) and vertical width expansion (lateral canthoplasty) are coordinated within the same surgical plan, the final eye contour ratio and harmony can be designed consistently.
Different from Skin Incision Lower Eyelid Surgery
Many people worry about ectropion after skin incision lower eyelid surgery, but this concern mainly applies to the skin incision method. According to the previously cited data, ectropion is closely related to excessive skin removal or palpebral septum damage—that is, vertical shortening of the anterior lamella. PMC/NIH 2025 data warns that if ectropion occurs, surgical correction accompanied by skin and cartilage grafting may be necessary, which is why the conjunctival incision method's preservation of the anterior lamella is important.
Of course, conjunctival incision is not always the answer. If severe skin ptosis requires skin removal itself, the skin incision method may be necessary, and the simultaneous surgery plan must be different in such cases. As PubMed/PMC clinical data points out, precise pre-evaluation must be a prerequisite in conditions where tension on lower eyelid tissue increases.
21plastic surgery's Diagnostic and Plan Development Approach
The primary criterion for determining whether to perform simultaneous surgery is eyelid laxity.
According to an article published in Archives of Aesthetic Plastic Surgery, when the snap-back test suggests laxity or the distraction test shows 7mm or more, it is recommended to perform outer canthus fixation together. Interestingly, those with eyelid laxity may actually need a surgical plan that addresses the outer canthus area together. In other words, eyelid laxity assessment is not a barrier preventing simultaneous surgery but rather a criterion for determining how to address both together.
21plastic surgery uses a comprehensive total eye cosmetic surgery consultation as the standard when planning under-eye fat repositioning and lateral canthoplasty. After comprehensively evaluating eyelid laxity, skin redundancy, eye corner angle, and orbital fat distribution, we design a simultaneous surgery plan individually for each patient.
Diagnostic and Plan Development Flow:
▪ Eyelid laxity evaluation (snap-back test / distraction test)
▪ Skin redundancy and elasticity evaluation
▪ Eye corner angle and scleral exposure measurement
▪ Orbital fat distribution and tear trough depth confirmation
▪ Determination of suitability for simultaneous conjunctival incision
▪ Surgical sequence and approach planning
Points You Should Know
While we've mentioned the advantages of simultaneous surgery, we also honestly guide you on aspects to be aware of.
In the previously cited 59-patient study, 3 cases of entropion (inward rolling of the eyelid) and 2 cases of eye corner rounding were reported, which recovered without recurrence after secondary surgery to correct fixation position. It's good to know before surgery that situations requiring correction can occur even at low frequency.
Conjunctival swelling (temporary puffiness of the sclera) is a common reaction that can occur after eyelid surgery, and performing both surgeries together may result in greater initial swelling compared to single surgery. While most resolve naturally, if it persists, it's safe to visit for examination.
Items requiring confirmation before surgery:
▪ Degree of skin ptosis (if skin removal is necessary, the surgical plan may differ)
▪ Eyelid laxity (outer canthus fixation method is determined based on laxity degree)
▪ Dry eye history or current symptoms (post-surgical dryness may temporarily increase)
▪ Recovery period availability
Post-Surgery Precautions:
▪ Swelling and bruising are most severe 2-3 days after surgery and subside over 2-4 weeks
▪ Final under-eye contour stabilizes approximately 6 months post-surgery
▪ If conjunctival swelling persists, immediate visit is necessary
▪ Early medical consultation is recommended if dry eye or eyelid pulling sensations occur
Results may vary depending on individual condition.
Confirm Which Method is Right for You Through Consultation
At 21plastic surgery located between Sinnon-hyeon Station and Gangnam Station, please confirm the direction suited to your eye structure through consultation.
Whether the advantages of simultaneous conjunctival incision surgery apply to you can only be accurately determined by directly examining your eyelid laxity, skin redundancy, eye corner angle, and fat distribution. We provide the same evaluation standards and guidance to patients from nearby areas such as Yeoksam, Seocho, and Nonhyeon who visit regarding under-eye fat repositioning and lateral canthoplasty.
Frequently Asked Questions
Q1. Will recovery take twice as long if done simultaneously?
No. Both surgeries are performed in the lower eyelid area, so the recovery processes overlap considerably. In fact, if done separately, you would experience the swelling and bruising recovery period twice, so simultaneous surgery is often more efficient in terms of overall timeline. However, initial swelling with simultaneous surgery may be greater than single surgery, and it's good to allow approximately 6 months for final stabilization.
Q2. What if conjunctival swelling occurs?
Conjunctival swelling is a reaction where the sclera becomes swollen as lymph circulation temporarily slows after eyelid surgery, and most naturally resolve without special treatment. It may appear relatively more with simultaneous surgery but remains a temporary reaction. If it persists, it's safe to visit for examination.
Q3. Can eye appear larger even with under-eye fat repositioning alone without lateral canthoplasty?
Under-eye fat repositioning is a surgery to improve under-eye bulging and tear trough hollowing to refine the eye area. While it has the effect of making eyes appear clearer and brighter, directly increasing the vertical eye width (scleral exposure) is the role of lateral canthoplasty. If the desired change is limited to under-eye refinement, single surgery may be sufficient in some cases.
Q4. Doesn't simultaneous surgery increase the risk of ectropion?
Ectropion is mainly a complication from the skin incision method when skin is excessively removed. Conjunctival incision preserves the anterior lamella (skin and muscle layer) and palpebral septum, so the risk structure itself is different, and clinical data also report that the ectropion incidence rate with conjunctival incision approach is low. However, this can vary depending on individual eyelid condition, so pre-evaluation is essential.
Q5. What if I still want them done separately?
Separate procedures are possible. However, with the conjunctival incision method, the incision approaches of both surgeries are adjacent, so doing them separately means not utilizing this advantage and experiencing two recovery periods. Conversely, if skin ptosis correction is necessary, separate or alternative surgical planning may be more appropriate, so the sequence and combination should be determined during consultation.
Results may vary depending on individual condition.