Does repeating the procedure lead to cumulative results? Research on multiple sessions

There is no large study confirming that cumulative effects increase with repeated procedures. In a review of 29 patients using PDO threads for eyebrow lifting, it was suggested that repeated sessions could accumulate tightening and lifting effects, but the sample size and follow-up period were limited.[1]Currently, the evidence is stronger for combining with other treatments than for increasing the number of sessions when it comes to durability.[2].

Where did this talk of 'cumulative effects' come from?

From the discussion section of a small preliminary study. In a retrospective review of 29 patients who underwent eyebrow lifting with PDO threads alone between January 2023 and January 2024, the change in eyebrow height in photos at 3 months was only approximately 1.2–1.3 cm.[1]Despite this slight elevation, the inner eyebrow angle changed by 4.00 degrees and 4.44 degrees, improving the appearance, and 26 of the 29 patients answered "satisfied" or "very satisfied," with no serious adverse events observed.[1]In the discussion of this study, it was stated that repeated procedures could generate new collagen and potentially accumulate effects.[1].

What's important to note here is that this is not a study that actually verified the effects of repeated procedures. It is a projection based on results of a single treatment observed over 3 months, and the authors themselves noted the limitations in scale and follow-up.[1].

What do studies on multiple sessions show?

In combined treatment approaches, there is data showing improved evaluation with each session. In a retrospective observational study of 58 patients divided into two groups of 29, where Thread lift and ultrasound were combined over 3 sessions, the physician's assessment of appearance showed significant improvement both between the first and second sessions and between the second and third sessions.[3]The measured distance of the sagging fat position below the cheek also decreased with each session.[3]However, the conclusion also states that the effects persisted in only some participants.[3].

Is there a set guideline for when to have the next procedure?

For Thread lift, there is no established recommendation. A multi-center review of over 110,000 cases does address changes in case numbers and patient backgrounds, but does not address the interval for individual patients' repeat procedures.[2]The same review states that Thread lift alone has limited effect durability, and better results were obtained when combined with other treatments.[2]The widespread use of hyaluronic acid in combination is also based on the observation that threads alone have limitations in long-term effects.[4].

Since the research side lacks a basis for determining the interval, in practice you will need to consult based on how the effects fade. If you are given guidance such as "every six months," ask about the evidence behind it.

What about the concern that repeated procedures make the tissue harder?

Direct data on Thread lift is not available. Relevant knowledge comes from other procedures: re-treatment of fibrotic tissue takes more time and carries increased risks of heat-related damage, fibrosis, scarring, and contour distortion.[5]Since this is a general principle regarding liposuction, caution should be exercised in directly applying it to the risks of repeated Thread lift.[5]The accurate approach at this point is to acknowledge what is not yet known.

The review concludes that what influences the result is not the type of thread but patient selection and individual planning.[6]The same perspective applies to the number of sessions.[6].

Confirm details at your consultation before deciding on the number of sessions

There are three things to verify: where and how many threads were placed last time, how those threads are thought to be now, and whether the next session will be in the same location or a different one. If you have records from your previous procedure, bringing them with you will speed things up.

If the goal becomes repeating the procedure itself, costs and burden accumulate. Discuss with your doctor what you want to restore and to what extent before deciding on your next step.