Who is suited for epicanthoplasty, and when does it become overdone? The dividing line depends on the strength of the epicanthal fold

Epicanthoplasty suits people who have a pronounced epicanthal fold (the skin fold covering the inner corner of the eye) and want to widen the eye horizontally inward[1]. Among the fold types common in Asian populations, types 2 and 3 are the target for this surgery, according to textbooks[1]. Conversely, in people with mild folds, there is no clear difference depending on the surgical technique, and some people undergo revision surgery to restore over-resected tissue, making it worthwhile to consider carefully[2][3].

What changes with the strength of the epicanthal fold?

The stronger the fold, the more the difference in surgical technique shows in the results. In a study comparing 172 patients using an improved Z-plasty (94 patients) and the conventional Z-plasty (78 patients), the improved technique had a higher rate of scar concealment in moderate to severe folds.[2]. In mild folds, this difference is not clear[2].

There are also reports that plan surgery by dividing the fold into three degrees. There is a research study that divided 17 patients into mild (3 people), moderate (8 people), and severe (6 people) and performed eyelid surgery simultaneously with inner canthus refinement[4]. A review summarizing methods to reduce scarring identified Z-plasty as the most frequently reported technique with minimal recurrence from mild to severe cases, while noting that there is still insufficient research comparing the advantages and disadvantages of different techniques by degree[5].

Who is more prone to scarring?

People whose skin is pulled with high tension. The main cause of scarring at the inner corner of the eye is high tension, and it is reported that it is important to adequately sever the fibrous connective tissue between skin and muscle to relieve tension[6]. Even the authors of the 172-patient study explicitly state that "zero scars" cannot be guaranteed with any technique[2].

Measures to minimize scarring are also being studied. A double-blind randomized trial comparing left and right sides of the face showed that injecting botulinum toxin in the early post-operative period can prevent hypertrophic scarring[7]. The review states that although the frequency of hypertrophic scarring has decreased relatively, scar appearance and fixation suture nodules remain as major sources of dissatisfaction[5].

When does overdoing occur?

When too much of the fold is removed and the shape of the inner corner no longer fits the face.[3]. There is a report of revision surgery to restore over-resected folds in 548 Asian patients, and 6% underwent further scar revision after the correction[3]. The very fact that this many people underwent revision is evidence that "wider is always better" does not apply in the initial surgery[3].

Conversely, if the release is insufficient, recurrence occurs. Inadequate skin movement causes the skin to be pulled back, leaving residual folds, as explained.[6]. Also, within the range of references consulted, no numerical standard was found regarding how many millimeters the distance between the inner corners should be. Rather than thinking in terms of "how much to widen," assessing suitability based on "fold strength" aligns better with current evidence.

Should it be done together with double-eyelid surgery?

Combining procedures is common. Epicanthal folds often coexist with single eyelids, and epicanthoplasty combined with double-eyelid surgery is described as a standard procedure to widen the eye horizontally.[4]. There are multiple surgical techniques, and in practice they are selected based on the surgeon's preference and experience, according to a report that organized this[8].

Therefore, it is more fruitful to ask "why that technique" rather than "which technique." How are your own fold degree, double-eyelid design, and scar appearance to be reconciled? If this explanation is concrete, you don't need to memorize the technique name.

What is the satisfaction rate and recurrence rate?

Satisfaction differed by technique. In the 172-patient study, very satisfied was 79.8% with the improved technique and 47.4% with conventional Z-plasty; dissatisfied was 0% with the improved technique and 6.4% with the conventional technique.[2]. There was no difference in recurrence between the two groups; 97.9% had no recurrence with the improved technique, and 2.1% had mild recurrence[2].

However, this is a retrospective comparison at the 6-month mark.[2]. Long-term recurrence and whether the same results occur at other facilities cannot be determined from this study alone.

Four things to confirm at your consultation

First, determine whether your epicanthal fold is mild, moderate, or severe.[1][4]. Second, ask where and how scars will remain, and whether measures are in place to suppress hypertrophy[6][7]. Third, ask how the amount of widening is decided and what criteria are used to avoid over-resection[3]. Fourth, if performing double-eyelid surgery simultaneously, clarify the design[4].

Fold strength, skin thickness, and intercanthal distance vary from person to person. Based on an article alone, you cannot decide whether surgery is right for your inner corner. At your consultation, have your fold degree and skin laxity examined directly, and confirm the range that can be widened and how scars will appear while looking in a mirror.