Laser Resurfacing: Assessment, Treatment Planning, & Technique

Overview of Laser Fundamentals

Laser resurfacing devices differ by wavelength, chromophore target, depth of penetration, and degree of thermal injury. Understanding these differences helps trainees choose the correct device for texture, pigment, vascularity, or scar remodelling.

Think in terms of chromophores and thermal injury

The clinical effect of a laser depends on:

• the chromophore absorbing energy,
• the depth of penetration,
• and the amount of collateral thermal spread.

In resurfacing:

• CO2 produces more coagulation and collagen contraction,
• Er:YAG produces cleaner ablation with less thermal damage,
• and fractional delivery leaves untreated skin between columns to accelerate healing.

Indications and Suitability

Laser resurfacing improves surface texture, dyschromia, fine-to-moderate rhytides, and selected scars by controlled epidermal and dermal injury. It does not correct significant facial descent, deep volume loss, eyelid malposition, or unrealistic expectations.

Match the indication to what resurfacing can actually change

The best indication is a visible skin-quality problem where controlled injury and remodelling can improve contour, texture, or pigment.

• Photoageing: resurfacing may be used for skin-ageing changes such as rhytides and actinic texture change. ²
• Acne scarring: ablative fractional CO2 is a supported option for improving acne scars.
• Postoperative scars: patients with post-Mohs scars can be counselled for laser as a less invasive scar-revision option with reported safety and satisfaction. ⁴
• Damaged skin: ablative resurfacing may be considered for photodamage, acne scars, hidradenitis-related scarring, and selected posttraumatic or post-excision scars.

Choose suitability before choosing the machine

Suitability depends on skin type, healing capacity, pigmentation risk, downtime tolerance, and the depth of the problem.

• Fractional CO2 candidate: facial rejuvenation is best suited to Fitzpatrick I–III patients aged 40–60 with moderate-to-advanced wrinkles and mild-to-moderate dyspigmentation. ¹
• Darker skin: Er:YAG is often preferred for darker-skinned patients undergoing cutaneous resurfacing. ⁶
• Milder change: short-pulsed Er:YAG suits mild rhytides, mildly atrophic scars, and textural changes from fibrosis or dermatochalasis. ⁶
• Broader Er:YAG use: Er:YAG may be considered across skin types and body sites for indications from lentigines to deeper rhytides.

Decline when resurfacing will create risk without benefit

Do not offer resurfacing to solve the wrong problem. Patients with brow ptosis, jowling, lower lid laxity, marked laxity, or deep tethered scars usually need another procedure or combination treatment.

• Active skin disease: postpone if infection, inflammatory flare, poor barrier function, or recent aggressive treatment is present.
• Healing risk: review keloid tendency, immunosuppression, smoking, radiation, and previous poor wound healing.
• Expectation mismatch: decline if the patient expects lifting, scar erasure, or permanent reversal of ageing.
• Timing conflict: avoid treatment immediately before unavoidable sun exposure or events requiring rapid social recovery.

Applied Skin and Laser Anatomy

Laser resurfacing is a controlled injury. The trainee must understand where the energy goes, how heat spreads, and which skin units must survive for safe healing.

Treat water as the main ablative target

Ablative resurfacing works because water-containing tissue absorbs energy, vaporises, and leaves a predictable wound with surrounding thermal effect.

• CO2 concept: ablative fractional lasers are planned as water-targeting devices that create injury to drive re-epithelialisation and remodelling. ⁴
• Er:YAG concept: Er:YAG has a higher affinity for water-containing tissue, supporting finer ablation when precision is prioritised.
• Thermal relaxation: pulse duration and stacking determine whether heat remains localised or spreads into adjacent dermis.
• Coagulation zone: more coagulation may improve haemostasis and contraction, but increases erythema, dyspigmentation, and scarring risk.

Plan fractional injury around columns and reservoirs

Fractional treatment leaves untreated skin between treatment zones, which provides epithelial reservoirs for faster closure.

• Microcolumns: fractional CO2 creates microablative columns through the epidermis into the dermis, relevant for scar remodelling and topical adjuvant delivery. ⁸
• Healing reservoir: hair follicles, sebaceous units, and untreated intervening skin support re-epithelialisation.
• Expected closure: microablative columns typically re-epithelialise within 2–3 days after fractional CO2 treatment. ⁸
• Nonfacial caution: neck, chest, and extremity skin have fewer adnexal reservoirs and tolerate aggressive resurfacing poorly.

Respect thin skin and functional borders

The same energy is not equally safe across all regions. Thin skin and scarred skin magnify thermal injury.

• Eyelids: thin skin, globe proximity, and ectropion risk require conservative settings and eye protection.
• Neck: reduced adnexal density and mobile skin increase scarring and pigment risk.
• Mandibular edge: visible transition lines occur if resurfacing stops abruptly.
• Scarred fields: previous surgery, radiation, burns, or undermining reduce vascular reserve.

Use chromophores to avoid the wrong laser

Laser choice should follow the target, not the brand name.

• Water: CO2 and Er:YAG target water for ablation and resurfacing.
• Oxyhaemoglobin: pulsed dye laser is anatomically aligned with erythema and telangiectasia treatment. ⁴
• Melanin: pigment-targeting requires caution in darker phototypes because competing epidermal melanin increases dyspigmentation risk.

Assessment and Planning

Assessment prevents the common errors: treating the wrong diagnosis, overtreating high-risk skin, and promising a result that the laser cannot deliver.

Take a history that changes the plan

The history should identify infection risk, pigment risk, photosensitivity, impaired healing, and poor timing.

• HSV history: ask about cold sores, previous outbreaks after procedures, and current prodromal symptoms.
• Medication risk: document isotretinoin exposure, photosensitising drugs, anticoagulants, immunosuppression, retinoids, and recent peels.
• Pigment behaviour: ask about tanning, post-inflammatory hyperpigmentation, melasma, and prior laser response.
• Healing history: record keloids, hypertrophic scars, radiation, smoking, diabetes, connective tissue disease, and poor wound healing.

Skin type is a planning variable, not a label

Phototype informs risk, settings, staging, and counselling.

• Fitzpatrick classification: the Fitzpatrick system is the most widely accepted phototyping method, based on sunburn tendency and tanning ability. ⁹
• Prediction value: skin phototyping helps predict outcomes of aesthetic procedures. ⁹
• Pigment risk: higher phototypes, melasma tendency, and recent UV exposure push planning toward staged, conservative treatment.
• Documentation: record baseline pigment, scars, rhytids, laxity, and asymmetry before treatment.

Examine the deformity before choosing the laser

Not all wrinkles or scars respond to resurfacing alone. Classify the dominant problem before discussing devices.

• Rhytids: separate fine etched lines from dynamic wrinkles, folds, and laxity.
• Acne scars: classify ice-pick, boxcar, rolling, hypertrophic, and mixed patterns.
• Ice-pick scars: assess for adjunctive or combination treatment rather than laser monotherapy alone.
• Atrophic scars: choose adjuncts according to scar type, severity, and number. ¹⁰

Build the plan around severity, skin type, and downtime

Planning should end with a clear decision: treat now, modify, stage, combine, or defer.

• Acne scar planning: session number, interval, parameters, phototype, scar severity, and scar type affect fractional CO2 effectiveness. ¹¹
• Facial ageing: treatment area, wrinkle depth, phototype, and dyspigmentation tendency should guide fractional ablative CO2 settings.
• Skin preparation: no universal consensus protocol exists for preprocedural skin preparation before ablative resurfacing, so document the local protocol you are using. A typical regimen is sun avoidance, cessation of retinoids or irritants several days before treatment, antiviral prophylaxis for HSV-risk patients, and pigment suppression such as hydroquinone in selected higher-risk phototypes. ¹²
• Consent record: document target, expected improvement range, downtime, pigment risk, infection risk, scarring risk, and need for staged treatment.

Decide whether to proceed, modify, or defer

Use a simple pre-treatment decision frame.

• Proceed: stable skin, suitable indication, realistic goals, acceptable pigment risk, and planned prophylaxis.
• Modify: darker phototype, melasma risk, mixed scars, eyelid or neck treatment, or limited downtime.
• Combine: tethered scars, ice-pick scars, volume deficit, dynamic wrinkles, or residual vascular redness.
• Defer: active infection, recent UV injury, pregnancy or breastfeeding, active dermatitis, poor adherence, or unstable expectations.

Device and Technique Selection

The device is only part of the decision. The trainee must also choose density, energy, number of sessions, intervals, and whether another modality is needed.

Select the device by the dominant clinical problem

The safest selection framework starts with the clinical target, then accepts the trade-off.

Choose CO2 when efficacy matters more than morbidity

CO2 is favoured when collagen contraction, deeper remodelling, and visible rejuvenation are the main goals.

• Wrinkle efficacy: CO2 may offer greater efficacy for facial wrinkles, while Er:YAG may be favoured when complication profile is prioritised. ¹³
• Er:YAG limitation: Er:YAG should not be expected to produce the same dramatic clinical and histologic improvement as CO2.
• Combined ablation: combined CO2 and Er:YAG may be selected to maximise targeted collagen contraction while limiting postoperative morbidity.
• High-risk areas: reduce energy, density, or passes around eyelids, neck, bony prominences, and prior scars.

Stage treatment when pigment risk is higher

Higher pigment risk should push the plan toward lower intensity, staged sessions, and strict sun control.

• Fitzpatrick III–IV: technique intensity should generally be reduced and staged across sessions compared with single higher-setting treatment in Fitzpatrick I–II skin. ¹
• Dark or sensitive skin: fractional radiofrequency or needling may be lower-risk alternatives or adjuncts. ¹⁰
• Dark acne scarring: PRP or fractional radiofrequency microneedling added to fractional laser may improve efficacy and reduce PIH.
• Melasma tendency: avoid aggressive heat-based treatment unless the indication and counselling are strong.

Combine only when the second treatment solves a defined problem

Combination therapy should not become automatic. Add treatments only for tethering, deep scars, vascularity, pigment, or downtime control.

• Deep acne scars: fractional laser may need subcision or punch techniques rather than laser alone.
• Vascular redness: use vascular laser adjuncts such as pulsed dye laser (PDL) when erythema or telangiectasia is the residual target.
• Radiofrequency caution: adding radiofrequency to CO2 should not be assumed to improve results and may prolong erythema. ²
• Treatment sequencing: avoid stacking multiple inflammatory procedures in high-risk skin without a staged plan.

Operative Principles

Operative failure usually comes from excessive energy, unsafe overlap, poor regional adjustment, inadequate protection, or missed infection risk.

Prepare the patient, room, and team before firing

Laser resurfacing is a controlled burn performed in a shared safety environment.

• Consent pause: confirm indication, target zones, settings, prophylaxis, and expected endpoint.
• Skin preparation: choose cleansing agents cautiously because efficacy and safety evidence for pre-laser preparation is sparse. ¹²
• Eye safety: use wavelength-specific eyewear and corneal shields for eyelid or periocular treatment.
• Airway safety: avoid oxygen pooling, use wet towels where appropriate, and coordinate with anaesthesia.

Build analgesia into the workflow

Pain control is a procedural requirement, not an afterthought.

• Pain expectation: pain is common during dermatological laser procedures, so analgesia should be planned.
• Anaesthesia choice: active non-invasive anaesthesia is preferable to none; topical anaesthetics and pneumatic flattening appear more effective than cooling.
• Topical protocol: lidocaine/tetracaine 7%/7% peel cream was applied 45 minutes before fractional resurfacing and removed immediately before treatment in a trial. ¹⁵
• Effect size: that cream reduced mean pain from 8.6 to 3.0 on a 10-cm VAS in a 30-patient trial. ¹⁵

Choose settings to hit the target, not the maximum

Parameters should be set to the indication, skin thickness, region, and risk profile.

• Target logic: wavelength and fluence should affect the intended target while limiting collateral injury during scar resurfacing. ⁴
• Fractional variables: energy, density, pulse duration, coverage, and passes determine depth and thermal burden.
• Non-ablative Er:YAG: settings should account for superficial temperature rise, partial epithelial preservation, and subepithelial matrix coagulation. ¹⁶
• Er:YAG margin: precise ablation with less thermal injury supports shorter healing times and a greater safety margin. ⁷

Execute in a controlled sequence

Order matters because erythema, oedema, smoke, and bleeding obscure endpoints.

1. Confirm the map: mark treatment boundaries, transition zones, scars, and regions needing reduced settings.

• Boundary control: feather edges to avoid visible stop lines.
• Regional adjustment: reduce intensity over eyelids, neck, thin skin, and scars.

2. Treat by aesthetic unit: work systematically so overlapped and skipped zones are visible.

• Overlap control: avoid pulse stacking unless deliberately planned.
• Endpoint check: stop when the planned clinical endpoint appears, not after a fixed number of passes.

3. Control plume and debris: visibility and staff safety deteriorate quickly without active evacuation.

• Plume control: use smoke evacuation close to the treatment field.
• Debris removal: wipe gently according to device protocol without traumatising the wound.

4. Dress immediately: the wound should leave theatre protected, cooled, and documented.

• Immediate care: apply the agreed occlusive or open-care regimen.
• Record: document device, settings, passes, endpoints, adjuncts, and complications.

Complications

Complications should be organised by timing and consequence. Escalate severe pain, spreading erythema, purulence, vesicles, visual symptoms, delayed healing, or early contracture.

Recognise early problems before they scar

Early complications are often treatable if identified before deeper injury or infection develops.

• Thermal injury: excessive pain, blistering, grey tissue, or sharply demarcated burns require senior review.
• Infection: pustules, honey crusting, malodour, spreading erythema, or systemic symptoms need swab and treatment.
• HSV: grouped vesicles, disproportionate pain, or known HSV history warrants prompt antiviral treatment.
• Acneiform eruption: occlusion, ointments, and inflammation may trigger papules or pustules.

Counsel pigment change as common in the right context

Dyspigmentation is central to consent, especially for acne scarring, darker skin, melasma tendency, and UV exposure.

• Acne scars: pigment changes after facial acne scar resurfacing were reported in up to 44% and usually lasted a few weeks.
• CO2 and Er:YAG: reported complications include erythema, hyperpigmentation, crusting, and rarely hypopigmentation. ¹³
• Expert experience: hyperpigmentation, contact dermatitis, and local infection were commonly discussed after fractional ablative CO2 resurfacing.
• Late pigment loss: hypopigmentation can be delayed and difficult to reverse.

Treat scarring and ectropion as high-consequence events

Scarring is uncommon but unacceptable when preventable. Watch functional borders closely.

• Overall adverse events: a systematic review of 1093 resurfacing patients reported adverse events in 106 patients, or 9.7%. ⁵
• Hypertrophic scarring: hypertrophic scarring was rare in that review, reported in five patients. ⁵
• Facelift combination: in simultaneous facelift and laser resurfacing, ectropion was reported in 0.12% and hypertrophic scarring in 0.51%. ¹⁸
• Escalation triggers: delayed epithelialisation, lid retraction, contracture, or expanding hypertrophic scar needs early specialist intervention.

Postoperative Care and Surveillance

Postoperative instructions must be specific to the device, depth, region, and patient risk. Generic “keep it clean” advice is not enough.

Protect the wound until the barrier recovers

The first priority is cooling, comfort, moisture balance, and avoidance of trauma.

• Immediate care: cold compresses and topical petrolatum are commonly used after fractional ablative CO2 resurfacing. ¹
• Occlusive care: petrolatum-based regimens reduce desiccation and friction over ablative wounds.
• Open care: lighter regimens may be used for less aggressive fractional or non-ablative treatment.
• Analgesia: prescribe simple analgesia and escalate if pain is worsening rather than settling.

Prevent infection while recognising protocol variation

Prophylaxis should follow local policy and patient risk, with a low threshold to treat suspected infection.

• HSV prophylaxis: expert consensus supports valacyclovir 500 mg for 5–7 days starting the day before or day of fractional ablative CO2 resurfacing.
• Bacterial prophylaxis: most expert panelists recommend it for fractional ablative CO2 resurfacing, but antibiotic choice is not standardised. ¹
• Red flags: vesicles, purulence, spreading erythema, fever, severe pain, or delayed healing require review.
• Swabs: culture suspicious crusting, pustules, or non-healing areas before changing treatment blindly.

Control inflammation and pigment risk

Sun exposure and premature active skincare can convert an uncomplicated procedure into dyspigmentation.

• Sun avoidance: strict photoprotection is mandatory while erythema and barrier disruption persist.
• Active skincare: active ingredients are generally restarted gradually between days 8 and 42 once healing permits. ¹
• Erythema expectation: reviewed rejuvenation studies reported erythema around 12.8 days with combination treatment versus 15.24 days with monotherapy. ²
• Pigment surveillance: review earlier in darker skin, melasma tendency, or any new brown-grey change.

Use follow-up to detect both complications and opportunities

Surveillance is not only complication screening. It also identifies whether further scar or texture treatment is appropriate.

• Early review: check epithelialisation, pain trajectory, infection signs, and adherence.
• Later review: assess erythema, pigment, contour, scar softening, and need for staged treatment.
• Mohs scars: laser scar revision after Mohs has been reported from immediately post-procedure through 4 years later. ⁴
• Perioral treatment: adverse events after perioral rejuvenation should be recognised early so treatment can start without delay. ¹⁹

Outcomes and Counselling

Counselling should focus on expected improvement, downtime, pigment risk, need for staged treatment, and the limitations of resurfacing compared with lifting or volume-restoration procedures.

Counsel improvement, not perfection

Patients should understand that:

• Laser resurfacing improves rather than completely removes wrinkles, scars, or pigment abnormalities.
• Several months may be required for maximal collagen remodelling and final results.
• Multiple treatment sessions are often required, particularly for acne scars, non-ablative resurfacing, and darker skin types.
• Laser resurfacing improves skin quality but does not replace procedures that address skin laxity, facial descent, or volume loss.
• Maintenance treatments and ongoing sun protection help preserve long-term results.

Match expectations to downtime and risk

More aggressive treatment generally increases:

• Wrinkle reduction and skin tightening.
• Collagen remodelling.
• Improvement in deeper scars and photodamage.

but also increases:

• Recovery time and postoperative erythema.
• Risk of post-inflammatory hyperpigmentation, particularly in darker phototypes.
• Risk of infection, prolonged healing, and scarring.
• Need for meticulous wound care and strict photoprotection.

References