Outcomes vary widely among different surgeons. Since subtle variations in technique may yield substantial effects, it is naïve to extrapolate the results obtained by a specialist to those expected from a less experienced surgeon using simplified or stock operations.
Even an expert will obtain variability in results. Especially with double eyelid surgery, tiny differences in fat and skin removal or the placement of incisions will generate noticeable effects on the final appearance.
Damaged skin, inborn ptosis, a shortage of eyelid fat, or unusual eyelid or epicanthal anatomy will also influence the outcome.
Patients with fully "single" eyelids are more likely to show mild but noticeable asymmetry after surgery.
In the setting of preexisting asymmetry, it should be expeced that at least some of the imbalance will remain.
If a patient has undergone previous double eyelid surgery (incisional or non-incisional), internal scarring and distortion will influence healing and the final outcome.
If a patient is older than forty, has heavy or sun-damaged skin, or has other medical conditions affecting the eyelids, results are not as predictable as in younger patients with healthier and stronger tissues.
Achieving consistently satisfactory results demands not only careful preoperative evaluation and planning but attention to surgical detail and a certain degree of luck. Achieving consistently near-perfect results, however, is simply not possible for any surgeon, and so some asymmetry should be considered the rule rather than the exception.
While patient preferences such as crease height and shape are taken into account during planning, final results cannot be guaranteed.
Especially when a patient has undergone previous double eyelid surgery years earlier or has experienced complications from surgery performed elsewhere, improvement may be less than hoped for.
Because all operations possess inherent limitations and drawbacks, plastic surgery is not as predictable as most people would like to believe, and only seldom is a patient fully satisfied with every aspect of the result.
To avoid disappointment, it is crucial that expectations not be set unrealistically high.