The clinical approach
Fractional resurfacing works by keeping each injury small enough that the skin around it can pay for the repair. Every focal spot drills a microscopic channel into tissue. Around that channel sits a ring of thermal coagulation, and around the ring a wider zone of sub-lethal heating. Untouched skin bridges the gaps and supplies the cells for reepithelialisation. Manstein and colleagues put numbers on this in 2004 in Lasers in Surgery and Medicine, describing microscopic treatment zones spaced 250 micrometres or more apart with reepithelialisation complete within a day.
Spacing decides the outcome before energy does
Our engineering archive is blunt on this, and it's the part brochures skip. Pick the wrong combination of pulse width and spot density and the coagulation rings merge. Once they merge you are no longer treating fractionally. You've ablated a continuous slab, the tissue sloughs, and it heals as a scar. Push the other way, with heat that never bridges between channels, and you buy the downtime without the remodelling. The target is thermal continuity between channels without confluent coagulation. Two numbers set it: pulse width and spots per square centimetre.
Pulse width also decides how much coagulation you get per spot. Short pulse, thin ring, cleaner ablation. Long pulse, wide ring, more collagen contraction and more residual heat sitting in the dermis. Neither is correct in the abstract. Thick hypertrophic tissue often wants the wider ring. Thin periorbital skin absolutely does not. This is also where thermal relaxation time comes in, the interval a target needs to shed roughly two thirds of its heat, which scales with the square of target size.
Fractional and pixel are not the same machine
Worth knowing before you line up quotes. A true fractional scanner places spots one at a time through a galvanometer, so density, pattern and scan area are all programmable, and each spot carries the full pulse energy. A pixel head fires its whole array at once through a fixed optic. Density is whatever the optic says, and each point receives only a fraction of the pulse. For scar work, where you'll drop density on darker skin and raise it along stubborn boxcar edges, programmable wins. Ask which one you're being sold. The two get described with the same marketing vocabulary.
Treatment protocol
A worked parameter set, straight from the archive
Our internal operation notes for erbium glass fractional treatment split the face into seven positions carrying five distinct energy windows - 12 to 32 mJ, 30 to 50 mJ (two positions), 25 to 42 mJ, 18 to 25 mJ and 10 to 25 mJ - with a seventh position left to operator judgement against patient feedback. Square pattern throughout, 2.0 x 2.0 cm scan area, density of 12 x 12 or 24 x 24 spots per square centimetre, pulse interval held at 1 ms. Same machine, same session, five different energy windows. That range is the whole argument for buying an adjustable platform instead of a fixed-preset one.
Two operational numbers from those same notes belong in your room planning. Topical anaesthetic sits for 20 minutes before you start. A full face runs roughly 1.3 to 2 hours. The notes also call for repeated treatment, at least three times, on the areas that matter. Scar work is a course. Anyone quoting a single session is quoting something else.
Space those sessions several weeks apart so remodelling can finish between passes. What you photograph at the end of a course is not what you see the week after a pass, and clinics that book too tightly end up stacking heat into tissue that hasn't settled.
Risk sits on two axes: skin type and energy. Ablative fractional work carries a higher rate of post-inflammatory hyperpigmentation and of scarring than non-ablative work, and darker skin carries more of that risk. A retrospective series of 1,160 treatments with a 1540 nm non-ablative fractional laser, published in JAAD International in 2023, reported adverse events in 12.07 percent of treatments, with prolonged erythema the most common at 7.84 percent and hyperpigmentation in about 1.1 percent. Test spots, conservative first passes and strict photoprotection are the standard mitigations. Any lesion whose diagnosis isn't certain needs a dermatology opinion, and biopsy where indicated, before a beam goes anywhere near it. Our page on post-inflammatory hyperpigmentation covers the management side.
Recommended equipment
Ablative or non-ablative, chosen by case mix
The CF-01 CO2 fractional laser runs at 10600 nm from a sealed RF-excited tube, rated 30 W, delivered through a 7-joint articulated arm into a galvo scanner. Focal spot is adjustable across 50 to 2000 um. Pulse energy runs 2 to 200 mJ in 2 mJ steps, pulse interval 1 to 100 ms, densities of 6 x 6, 12 x 12 and 24 x 24 spots per square centimetre across 1 x 1, 2 x 2 and 3 x 3 cm scan areas. It also runs continuous wave and ultrapulse modes, so one trolley covers soft-tissue cutting and focal ablation as well as gridded resurfacing. Our engineering archive puts maximum ablation depth near 4 mm at the tightest focal spot. Deep atrophic scarring and firm surgical lines are its territory. Cooling is air, which means no chiller and no water loop to plumb in.
The EF-01 1550 nm fractional laser covers the non-ablative side. Erbium glass fiber source, TEM00 beam, pulse width adjustable from 0.067 to 6.7 ms, penetration to roughly 2 mm with micro-channels around 0.12 mm across. Surface coverage runs from about 1.56 percent at 36 spots per square centimetre to about 25 percent at 576. Those coverage percentages are the honest way to compare aggressiveness between two platforms, far more useful than a watt rating. Ask every vendor for theirs and watch how many can't produce them.
| Spec | CF-01 | EF-01 |
|---|
| Wavelength | 10600 nm | 1550 nm |
| Tissue effect | Ablative | Non-ablative |
| Pulse width | Not stated on the specification sheet; pulse interval 1 to 100 ms | 0.067 to 6.7 ms, adjustable |
| Focal spot | 50 to 2000 um | 50 to 2000 um |
| Spot density | 6 x 6, 12 x 12, 24 x 24 per cm2 | 36, 144, 576 spots per cm2 |
| Fractional coverage | Not stated - ask the vendor for the figure | ~1.56% / ~6.25% / ~25% at 36 / 144 / 576 spots |
| Stated depth | Ablation to about 4 mm at the tightest focal spot | About 2 mm, micro-channels about 0.12 mm across |
| Cooling | Air | Air |
| Downtime | Longer - the surface is removed and has to close | Shorter - the surface stays intact |
| Best-fit scar type | Deep atrophic scarring, firm surgical lines | Shallow rolling scars, general textural damage, darker phototypes |
Clinics with real scar volume tend to end up with both, and they rarely buy them in the same year. If acne scarring is the bulk of your caseload, the acne and acne scars workflow page is the closer match to how you'd actually schedule the room.
What to verify at acceptance
- Request the laser product classification under IEC 60825-1, in writing.
- Request the equipment safety file against IEC 60601-2-22, the particular standard covering Class 3B and Class 4 surgical and cosmetic laser equipment.
- Check the CE documentation handed to you is current rather than a scan from an earlier directive era. Our own certification archive holds conformity declarations old enough to prove the point, which is exactly why you check dates rather than logos.
- Specify wavelength-rated eyewear for every wavelength in the room, not one pair for the clinic.
- Get spare lens cones and fractional tips quoted up front, before the discount lapses.
- Confirm the lead time on the laser source itself, since the source is the single largest line on any quotation in this class.
Installation, calibration and consumable questions sit on our service page.
Frequently asked questions
CO2 at 10600 nm or 1550 nm for scars?
Depends on the scar and on the skin around it. Deep, sharply walled atrophic scars need tissue removed and rebuilt, and that's ablative work. Shallow rolling scars, general textural damage, and any patient who cannot lose a week to recovery do better on the non-ablative route. Darker skin types tilt the choice toward 1550 nm as well. A lot of clinics use both across a single course rather than picking a side.
What spot density should operators start at?
Lower than instinct suggests. Density is the control that quietly turns a fractional pass into a full ablation, and it's the first setting to drop on darker or thinner skin. The facial protocols in our archive sit at 12 x 12 or 24 x 24 spots per square centimetre, with energy varied zone by zone rather than density. Start conservative, photograph properly, escalate at the next visit.
How many sessions does a scar course take?
More than one, always. Our internal operation notes specify repeated treatment at least three times on the areas that need it, and older or deeper scarring runs longer than that. Collagen remodelling is slow and gradual, so improvement accumulates between visits rather than during them. Patients need telling this on day one, not at session three.
Will a laser remove a scar completely?
No, and it's cheaper to say so early. Laser work changes depth, colour and texture, sometimes dramatically, but it does not restore original dermal architecture. The updated international clinical recommendations on scar management published in Dermatologic Surgery in 2014 place laser inside a combination approach alongside other modalities rather than treating it as a standalone cure. Frame the goal as meaningful improvement.
Do these platforms need a chiller or special power?
Neither one here does. Both are air cooled, which removes the water loop, the drain-down before a service visit, and one recurring failure point in humid climates. Input is standard mains. What they do need is a room you can control: laser signage, interlock discipline, non-reflective surfaces near the beam path, and eyewear rated for the wavelength actually in use. Talk to us through the contact page if you want the room checklist before the machine ships.
References
- Manstein D, Herron GS, Sink RK, Tanner H, Anderson RR. Fractional photothermolysis: a new concept for cutaneous remodeling using microscopic patterns of thermal injury. Lasers Surg Med. 2004;34(5):426-438.
- Gold MH, McGuire M, Mustoe TA, et al. Updated international clinical recommendations on scar management: part 2 - algorithms for scar prevention and treatment. Dermatol Surg. 2014;40(8):825-831.
- Adverse events associated with 1540-nm nonablative fractional resurfacing in darker skin: A retrospective study. JAAD International, 2023.
- IEC 60601-2-22:2019 - Medical electrical equipment, Part 2-22: Particular requirements for basic safety and essential performance of surgical, cosmetic, therapeutic and diagnostic laser equipment
- IEC 60825-1:2014 - Safety of laser products, Part 1: Equipment classification and requirements