Tixel vs fractional CO2 vs RF microneedling:
three ways to injure skin on purpose

What is the difference between Tixel, fractional CO2 and RF microneedling?

Each of the three is fractional: it treats a pattern of small zones and leaves the skin between them intact, so healing proceeds from the bridges. What differs is the physics inside each zone.

Tixel is the odd one out because it uses neither light nor current. Its maker, Novoxel, describes the tip as biocompatible titanium pyramids on a gold-plated base, heated by a flat ceramic element; the clinician sets the speed and distance at which the tip contacts the skin and the number of pulses. There is no chromophore and no return pad, which is why it can be brought close to the eye and why its heat stays shallow. The fractional laser glossary entry explains the grid principle the three share.

Which goes deepest, and why does depth decide the scar?

Depth decides what each treatment can change. An acne scar is architecture: a wall, a floor and sometimes a tether running down to the fat. A treatment that cannot reach the edge of the wall can smooth the skin around it but not reshape it.

Tixel

Heat delivered by contact falls off quickly with depth, so Tixel's effect sits in the epidermis and upper dermis. The randomised periorbital study that compared it with a 1565 nm non-ablative laser found both produced moderate improvement in fine wrinkles, which is the level at which the technology works well. It is not a tool for a deep boxcar or a tethered rolling scar.

Fractional CO2

CO2 light is absorbed so strongly by water that each column is vaporised, leaving an open channel with a rim of heat around it. The channel reaches the scar edge, and the rim drives contraction and a strong collagen response. On the DEKA Tetra Pro, Pulse Shape Design lets Dr Sin Yong set how each pulse rises, dwells and tails off, so ablation can go deep and narrow into a scar edge and shallow and wide across the surrounding skin. In his S3 Resurfacing Lift, point shots are placed into individual pits before fractional passes, and the laser is sequenced after subcision for tethered scars and TCA CROSS for ice-pick tracts.

RF microneedling

The needle sets the depth directly. On the Secret DUO, needles are placed between 0.5 and 3.5 mm in 0.1 mm steps and release bipolar radiofrequency in the dermis, with insulated needles sparing the epidermis. That makes it the deepest of the three that leaves the surface intact, and the reason it is favoured for rolling scars and early laxity in darker skin. It heats rather than removes, so a sharp scar edge is softened more than it is reshaped; the S3 Resurfacing Lift vs Secret RF comparison sets out how the two are chosen and combined.

“A scar edge has to be reached before it can be reshaped. Heat that stays on the surface softens skin; it does not rebuild a wall.”

Dr Sin YongOn choosing between fractional treatments for acne scars

What does the downtime look like after each?

The recovery pattern follows the surface. Where the surface is removed, there is an open phase; where it is heated through, there is a pinpoint or sandpaper phase; where it is only warmed, there is redness. Durations vary between people and settings, and are discussed at assessment rather than promised.

• After Tixel: redness and a fine grid of brown micro-crusts where each pyramid touched, which shed; swelling is mild and mainly periorbital. The published chart reviews in skin types II to V describe this as the expected course.
• After fractional CO2: an open, weeping phase with swelling, then a bronzed, sandpaper phase as the columns re-epithelialise, then pinkness that fades. Moist healing, no picking and shade are the rules while the skin is open; the CO2 laser downtime guide describes the day-by-day course.
• After RF microneedling: pinpoint bleeding on the day, redness and a grid of tiny scabs at the needle entry points, and mild swelling. Because the surface is largely intact, make-up can usually be worn sooner than after CO2; the RF microneedling downtime page gives the detail.

Pain follows the same gradient. Tixel is usually done with topical anaesthetic alone; RF microneedling with topical anaesthetic and sometimes more for deeper settings; fractional CO2 at scar-resurfacing depth with topical and local anaesthetic. None of the three is suitable with active acne in the field, a current cold sore, a recent tan or isotretinoin within the interval Dr Sin Yong sets.

Can any of them be used on the eyelids?

Eyelid skin is the thinnest on the body and sits over the eye, so the question is not only what works but what is safe to bring that close. Tixel's claim to the periorbital area rests on having no laser beam: its 2023 clearance added the treatment of periorbital wrinkles, and ophthalmologists use a low-energy setting along the eyelid margin for evaporative dry eye, with a shield placed over the eye. Its depth suits fine crepe at the lateral canthus and lower lid.

Fractional CO2 can be used on the lower lid and around the orbit with metal eye shields in place and low density, but it is a wound on the thinnest skin on the face, and in Asian skin that is where darkening is most likely. RF microneedling with the shortest needles and a small tip is used around the orbit by some practitioners; needle depth has to be shallow enough for the lid, which limits the energy that can be delivered.

At this practice heavy or hooded upper lids are not treated by fractional resurfacing at all. The assessment on the droopy eyelids treatment page separates brow descent, lid skin and muscle: ptosis is referred, and lid skin is treated with the FSX Laser, a non-ablative 1540 nm and 1927 nm protocol, or the VF Lift – Vertical Facelift with the 0.25 cm² tip. The FSX Laser vs VF Lift – Vertical Facelift for droopy eyelids comparison explains which is chosen for which lid.

Which is gentler on Asian skin, and how is darkening avoided?

No device is safe or unsafe in itself; the risk is post-inflammatory hyperpigmentation, and it tracks heat, ablation and density. Fitzpatrick III to V skin carries more epidermal melanin and melanocytes that respond readily to inflammation, so the same setting that passes without comment on lighter skin can leave a brown shadow after an Asian face has healed. The retrospective Hong Kong series that first measured this after fractional resurfacing found that density, the proportion of skin treated, mattered more than energy; the same group's series on fractional CO2 in Chinese patients recorded darkening in many patients at one month that had largely settled by six.

That ordering puts fractional CO2 on the highest rung of the risk ladder, RF microneedling with insulated needles near the bottom, and Tixel somewhere in between depending on how hard the tip is pressed. It is why, for a Fitzpatrick IV patient with rolling scars and no sharp edges, Dr Sin Yong often reaches for the Secret DUO first; why the Tetra Pro is run at a lower density and a shaped pulse when the scar pattern does need ablation; and why every plan here includes preparation, antiviral cover where indicated, a pause on actives, shade while the skin is open and daily sunscreen once closed. The full reasoning is on fractional CO2 in Asian skin and RF microneedling in Asian skin. If a mark has already appeared, it is treated as post-inflammatory hyperpigmentation, not as a reason to resurface again.

What decides the plan, in order: the scar type and depth found on mapping; the Fitzpatrick type and any history of darkening; whether tethers or ice-pick tracts need subcision or TCA CROSS first; how much recovery time is realistic; and what has been done to the skin before. Tixel is described here so that a patient who has been offered it elsewhere can place it on that ladder; it is not a treatment Dr Sin Yong performs.