Laser Lifting

XERF in Seoul: What to Plan Before Your Visit

For visitors planning XERF at RESUM Plastic Surgery Clinic in Gangnam, Seoul: the time a session needs, what the skin does in the first days and how the result develops after you leave.

Plan a consultation

Published: 2026-10-15

Updated: 2026-10-15

At a glance

XERF is a non-invasive monopolar RF device that uses two frequencies, 6.78 MHz and 2 MHz, in one session.
A session takes about 20-40 minutes under numbing cream, with a return to daily activities right after.
New collagen changes start to show from 4-6 weeks and build over 2-3 months.

What is XERF?

Cynosure Lutronic developed XERF as a lifting device that works with radiofrequency (RF). It is non-invasive and works with two frequencies in the same session: 6.78 MHz warms the collagen in the dermis, and 2 MHz travels further down, as far as the layer of fat under the skin. Texture near the surface and firmness in the deeper layers can therefore be treated on one visit.

While it runs, the device cools the skin surface and measures the skin's electrical resistance (impedance) in real time, matching the energy to each person. The doctor's part is deciding how much of each frequency you receive.

How long does an XERF session take?

An XERF session takes about 20-40 minutes. The tip covers a large area, which helps when the full face, jawline and neck are treated together. Add the consultation and the wait while numbing cream takes effect, and you can go straight back to your day afterwards. Let us know your travel dates before you come.

Session	About 20-40 minutes
Numbing	Numbing cream
Back to daily activities	Right after the session
How long it lasts	About 12 months

What XERF cannot do

XERF on its own is not enough for advanced sagging or deep lines. If the sagging sits at the depth of the SMAS, Ultherapy is the option suggested. If the whole dermis needs more contraction, Thermage or a combined plan is suggested, and when facelift surgery fits better, that is assessed too. RESUM says this openly in the consultation instead of recommending XERF regardless.

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Purpose & suitability

You want firmer skin and smoother texture without giving up facial volume.

You are sensitive to pain and would prefer a treatment done under numbing cream, without IV sedation.

You have tried Thermage or Oligio by itself and found the change insufficient.

Your time in Seoul is limited and you want the dermis and the deeper layers addressed in one session.

You intend to repeat the treatment 1-2 times a year as regular care.

Treatment process

Assessment. Skin thickness, where the sagging is and the real-time impedance reading are checked to set the criteria for your treatment.
Frequency plan. The doctor decides the share of 6.78 MHz and 2 MHz, the depth and the number of applications for each area.
Numbing and treatment. After numbing cream, RF is delivered with automatic cooling on the surface and energy matched to your impedance.
Before you leave. You hear what to expect from 4-6 weeks onward, how to look after the skin and when a booster session would be due.

Time & recovery

Mild redness, slight swelling or a flaky feel can appear for 1-2 days and settles by itself. Makeup covers it in most cases.

For 1 week, skip saunas and hot compresses. Keep up sun protection and avoid irritating skincare products while collagen is forming, which also helps prevent hyperpigmentation.

A first change from collagen contraction may be noticed on the day. New collagen changes show from 4-6 weeks and accumulate over 2-3 months, while collagen formation itself continues for 4-6 months. Judge the result well after you are home.

Limitations & precautions

During pregnancy, XERF is not recommended. Where acne is active or inflammation is severe, the doctor decides in the consultation whether RF can be used on that area.

Temporary hyperpigmentation or itching in the treated area occurs in rare cases. Cooling and impedance checks keep the risk of burns low, and the intensity is set within a range that suits your skin and pain sensitivity, not at the device maximum.

How the two frequencies are divided, and the result, vary with skin thickness and the pattern of sagging. Please consult Dr. Jin-Young Kim before treatment.

Frequently asked questions

Is a short trip to Seoul enough for XERF?

Yes, in most cases, since an XERF session takes about 20-40 minutes and daily activities resume right after. Redness or swelling can last 1-2 days, and saunas should be avoided for 1 week.

Does XERF hurt?

XERF is carried out under numbing cream and does not require IV sedation. Automatic cooling protects the surface, the energy is adjusted to your skin's impedance, and the doctor sets the intensity according to your sensitivity to pain.

How is XERF different from Thermage?

Both are monopolar RF, and the 6.78 MHz of XERF is the same band Thermage uses for the dermis. XERF adds a second frequency, 2 MHz, that goes deeper, down to the subcutaneous fat layer, which widens the choice of depth.

Will I see the result before I fly home?

Partly. A change from collagen contraction may be noticed right after XERF, but new collagen changes appear from 4-6 weeks and build over 2-3 months. Most of the result therefore shows after you have left Seoul.

How long does XERF last, and how often is it repeated?

The result of XERF lasts about 12 months. Regular care is usually planned 1-2 times a year, and Dr. Jin-Young Kim plans the allocation of the two frequencies for each patient.