Key facts
- Responds
- Untethered rolling scars and shallow boxcar scars: dermal collagen loss that heat at depth remodels
- Responds after another step
- Tethered rolling scars after subcision; deep boxcar walls alongside fractional CO2
- Does not respond
- Ice-pick tracts, which need TCA CROSS; raised hypertrophic or keloid scars, which need a different plan
- How depth is set
- Needle depth and energy chosen per scar field from the stretch test and skin thickness
- Risk specific to scars
- Post-inflammatory darkening in Fitzpatrick III to V skin, grid marks if energy is stacked
- Fee
- Set in writing after assessment; see how fees are quoted
Which acne scars does RF microneedling respond to?
RF microneedling responds to acne scars whose problem is lost or disorganised dermal collagen with nothing holding the floor down: untethered rolling scars and shallow boxcar scars. In both, the needles pass to a set depth beneath the scar and release radiofrequency heat at the tips, creating small coagulation zones in the dermis that the skin repairs with new collagen and elastin, so the floor of the scar is gradually supported from beneath. The RF microneedling page explains the mechanism; this page is about which scars it fits.
Three scar types sit outside that fit. A tethered rolling scar is held down by a fibrous band, and heating the dermis around a band that is still attached changes little until subcision has released it. An ice-pick scar is a narrow tract that reaches deeper than the needles usefully go, and it is collapsed with TCA CROSS. A raised hypertrophic or keloid scar is too much collagen rather than too little, and needling it can provoke more. The acne scar types guide shows how each is recognised.
How is the scar type confirmed before the needles are chosen?
The scar type is confirmed by stretching and lighting the skin, scar by scar. A depression that flattens when the skin is pulled taut is a rolling scar with no tether; one that dimples or deepens on stretch is tethered from below; a depression with a defined edge and a flat floor is a boxcar scar, and its depth is judged in angled light; a pinpoint hole that seems to have no floor is an ice-pick scar. Dr Sin Yong maps the cheeks, temples and jaw this way before deciding where RF microneedling applies, because most faces carry more than one type in the same square centimetre.
Skin type and history are mapped alongside. Fitzpatrick III to V skin, a past of post-inflammatory darkening, recent isotretinoin, a tendency to keloid and active acne each change the settings or the order of work. Active inflamed acne is brought under control first, because needling through it is the wrong order and new scars form while old ones are treated. The acne scar treatment page sets out the full toolkit and how the steps are sequenced.
“If someone offers you one treatment for your acne scars, they haven't looked closely enough.”
Dr Sin YongOn mixed acne scars · from his Instagram explainer series
How are needle depth and energy set for different scars?
Depth follows the scar and the zone. Beneath a rolling scar on the cheek the needles are set deeper, into the mid to deep dermis where the collagen loss sits; over a shallow boxcar field they are set shallower; over the temple, the jawline and anywhere thin skin lies over bone they are set conservatively. Energy follows depth and skin type, and in Fitzpatrick IV to VI skin insulated needles, which release heat only at the tip and spare the epidermis, are generally chosen, with non-insulated needles kept for broad, shallow texture work.
Passes are not stacked over the same point. Overlapping high-energy passes are what leave the grid or tram-track marks sometimes seen after RF microneedling, and they add heat without adding remodelling. Where the surface around a scar also needs attention, the 1540 nm non-ablative fractional laser on the same Secret Duo platform may be used in the same visit. Progress is judged at review against photographs taken at assessment, and the plan is adjusted to how each scar field has responded rather than fixed in advance.
Acne scar types and how RF microneedling fits each| Scar type | What it is | RF microneedling's role |
|---|
| Rolling, untethered | Broad, soft depression from dermal collagen loss; flattens on stretch | A direct fit; depth set to the dermis beneath the scar |
| Rolling, tethered | Dimples deepen on stretch; a fibrous band holds the floor down | After subcision has released the band, not before |
| Shallow boxcar | Flat floor, defined edges, shallow depth | A direct fit, often with the 1540 nm laser on the same platform |
| Deep boxcar | Flat floor with steep, deep walls | Partial; fractional CO2 resurfaces the walls, RF remodels the floor |
| Ice pick | Narrow tract reaching deep into the dermis | No; TCA CROSS collapses the tract first |
| Hypertrophic or keloid | Raised, firm scar tissue above the surface | No; see the keloid treatment page |
What is staged before or alongside RF microneedling for mixed scarring?
Mixed scarring is staged so that each step does the job the others cannot. Subcision comes first for tethered scars, releasing the band so the skin can lift from beneath; TCA CROSS is placed into ice-pick tracts; fractional CO2 resurfacing with the S3 Resurfacing Lift sculpts deep boxcar walls and coarse texture; RF microneedling then remodels the dermis under rolling and shallow boxcar scars once they are free to respond. Pigmented acne marks are treated separately with pigment-directed laser rather than with needles.
Doing the steps in the wrong order wastes them. Needling over a tether treats the surface of a structure that is still being pulled down; resurfacing a face with active acne creates scars as it treats them. The sequence, and how many of the steps a particular face needs, is set at assessment, and the subcision page explains the step that most often comes first.
What are the risks specific to scar work, and what determines the fee?
The risks specific to acne scar work come from treating deeper and more densely than for texture alone. Post-inflammatory darkening is the commonest concern in Fitzpatrick III to V skin, raised by sun exposure during healing, by energy too high for the skin and by non-insulated needles used at depth; it tends to fade with protection but can take a long time. Grid marks follow stacked passes. An acne flare, a cold sore outbreak, small scabs, prolonged redness and, in keloid-prone skin, new raised scarring are the other risks, and infection is uncommon when the skin is kept clean. Worsening redness, pain, swelling, pus or dusky skin should be reported the same day.
The fee follows the scar map rather than a list: which scar types are present and across what area, what depth and cartridge each field needs, whether subcision, TCA CROSS or fractional laser is staged with it, and how the plan is reviewed. Singapore's rules prevent clinics from advertising prices, so no figures appear here; a written quote follows assessment, as the how fees are quoted page explains.
