Introduction

Laser resurfacing is a very popular procedure in the United States and worldwide. Data from The American Society of Aesthetic Plastic Surgery collected yearly from core specialists since 1997 through 2010 has shown the rise, fall, and rise again of this procedure as devices have been introduced (Table 7.1). In the mid 1990s carbon dioxide lasers were extremely popular, but toward the turn of the century they fell out of favor and were somewhat replaced by non-ablative technology. Laser resurfacing resurged in the last 5 years with the introduction of fractional lasers.

History

Lasers were introduced into the plastic surgery and dermatology world initially for the treatment of vascular lesions. The introduction of the carbon dioxide laser for skin resurfacing in the mid 1990s rapidly became popular and replaced chemical peels and dermabrasion in many practices. The carbon dioxide laser has a wavelength of 10 600 nm, an absorbing chromophore of water, and is used to vaporize tissue. Continuous mode lasers were initially used, but complications due to excessive depths of ablation and thermal damage led to advances to deliver short laser pulses to the skin to minimize complications. Competing technology delivered either short pulses, each of which contained enough energy to cause tissue ablation (Ultrapulse^® laser, Lumenis lasers, Yokneam, Israel) or an optomechanical flashscanner used to scan a continuous laser beam in a spiral pattern (Silk-touch^® and Feather-touch^® lasers, Lumenis lasers, Yokneam, Israel). Both methods created a tissue exposure time of less than one millisecond, which allowed tissue ablation with limited residual thermal damage of approximately 75–100 µm. Short-term results of eradicating wrinkles and tightening lax tissue were excellent, but longer-term follow-up showed hypopigmentation in a large percentage of patients. These pigmentary complications and the considerable downtime created for the patient led to the demise of ‘full field’ carbon dioxide laser resurfacing around the turn of the century.

Erbium : YAG lasers (2940 nm) were introduced around 2000 and marketed for superficial resurfacing. Erbium lasers have a higher water absorption coefficient than carbon dioxide lasers (about 10 times more efficient) and ablate tissue with much less thermal damage (5–10 µm). Initial machines were low powered, lacked pattern generators, and needed considerable number of passes and treatment time to achieve deeper depths of ablation. Subsequent systems had more significant power and could be used for efficient deeper resurfacing. There is a linear relationship between the energy delivered and depth of ablation, with approximately 3–4 µm ablated per joule of Er : YAG laser fluence delivered. Complications were fewer, yet downtime appeared to be similar to that of carbon dioxide systems. Conclusions of comparative studies were that the combined depth of ablation and coagulation was the determining factor in length of recovery. Combination systems of carbon dioxide and Er : YAG lasers were popular for a short time (Derma-K^®, Lumenis lasers, Yokneam, Israel) with the beams being delivered either sequentially or at the same time.

Variable or long-pulse Er : YAG lasers (Sciton Inc, Palo Alto, CA) allow control over the amount of residual thermal injury produced for a given amount of tissue removal. These variable pulse Er : YAG systems seem to produce skin tightening and wrinkle reduction similar to carbon dioxide lasers with a much shorter period of erythema and much lower risk of hypopigmentation. These devices are very popular today.

Other wavelengths for skin resurfacing have been introduced (2780 nm and 2790 nm) (Cutera Lasers, Palomar Lasers) which allow variable degrees of thermal damage and ablation settings but have not had significant commercial success. Plasma skin resurfacing uses nitrogen plasma energy to coagulate a very controlled depth of skin. Healing times and results appear to be similar to Er : YAG lasers. These devices were popular for some time, but were removed from the marketplace due to financial problems of the manufacturer. They were recently reintroduced into the market.

In 2004 Manstein et al introduced the concept of fractional photothermolysis. Full field or traditional laser resurfacing as described above removes the entire skin surface in the area being treated with depth of injury depending upon energy level, whereas fractional laser resurfacing treats a small ‘fraction’ of the skin at each session, leaving skip areas between each exposed area (Fig. 7.1). This was first performed commercially using non-ablative fluences at 1550 nm (Solta Medical, Mountain View, CA). These non-ablative fractional lasers created a column of thermal damage with intact epidermis. Healing occurred from deeper structures as well as from adjacent structures. This differs from full field resurfacing in which healing occurred from only deeper structures. Deeper treatments (i.e. to the reticular dermis) can safely be performed using this approach than would be tolerated using a full field treatment. Advantages of this approach include avoidance of an open wound and very low risk of pigment disturbance or scarring. Disadvantages have included the need for multiple treatments and somewhat less clinical response than with full field ablative resurfacing. Since the introduction of the original system there have been many manufacturers that have introduced similar non-ablative fractional devices with wavelengths of 1440 nm, 1540 nm, and 1550 nm. These devices differ in power output, spot size, density, etc. and comparisons of clinical efficacy are difficult, yet similar degrees of tissue injury should produce similar clinical results.

Figure 7.1 Traditional ablative laser resurfacing (full field).

Fractional ablative resurfacing with carbon dioxide, erbium, and yttrium-scandium-gallium-garnet (YSGG) systems was introduced with the intent of providing more significant results than non-ablative fractional systems while achieving shorter healing times and complications when compared with full field ablative systems (Fig. 7.2). These devices differ not only in wavelength but in system power, spot size, and amount of thermal damage created adjacent to and deep to the ablated hole. One popular erbium system, the Sciton ProFractional^®, allows one to vary the amount of thermal damage similarly to their full field system. Other newer carbon dioxide fractional lasers allow variation of the thermal damage zones (Deka Medical) while others allow superficial and deeper penetration with a single scan (Syneron, Yokneum, Israel). As with the non-ablative fractional systems, direct comparison between devices is difficult as devices differ in power output, spot size, density, and degree of thermal damage, but similar degrees of injury should produce similar clinical results.

Figure 7.2 (A) Fractional treatment; (B) ablative fractional laser treatment.

The newest wavelength to be introduced into the fractional arena is the Thullium^® (1927 nm) by Solta Medical. This non-ablative fractional device is especially effective in removing superficial pigment. Full field ablative resurfacing and both fractional ablative and non-ablative systems remain very popular in clinical use at this time.

Patient selection

Patient selection and a clear understanding of potential complications are important to achieving consistent results. The most common indications for both full field and fractional laser resurfacing are superficial dyschromias, dermatoheliosis, textural anomalies, superficial to deep rhytides, acne scars, and surgical scars. Other conditions that may respond favorably include rhinophyma, sebaceous hyperplasia, xanthelasma, syringomas, actinic cheilitis, and diffuse actinic keratoses. Dyschromias such as melasma have been successfully treated with fractional resurfacing but results are not consistent. The usual area for resurfacing is the face, but body and neck skin may be treated with variations of technique. Non-facial areas lack the appendages necessary for skin rejuvenation and treatment must be performed non-aggressively to avoid complications. These devices are generally used with patients with Fitzpatrick skin types I–IV, but can be used in skin types V and VI with modification of technique.

Patient assessment starts at the consultation with observation of the patient’s Fitzpatrick skin type, ethnicity, and pathology to be treated. For example, deep acne scarring will not be successfully treated with a single treatment of non-ablative fractional treatment, but mild textural issues may respond to superficial treatment. The next assessment is of the patient’s tolerance of healing period ‘downtime’. A busy executive with no urgency for end point of clinical results may be able to be treated only with a series of no-downtime non-ablative fractional therapy, whereas the bride’s mother looking for maximum improvement in a short time to look her best for her daughter’s wedding may need a single session with more aggressive treatment. The last parameter is one not usually discussed in medical journals or book chapters: patient finances. A deep full field resurfacing performed under general anesthesia will be more expensive for the patient then a superficial treatment performed with topical anesthesia. However, in patients with deep rhytides a more aggressive procedure under general anesthesia may be more cost effective than multiple more superficial treatments. Another consideration is laser resurfacing while patients are undergoing other procedures such as facelift, abdominoplasty, or aesthetic breast surgery. These patients often have built-in downtime from other procedures and have the recovery time available for deep resurfacing.

Many of us with various devices in our offices can offer patients a plethora of treatment options and this can be very confusing to the patient. An effective consultation will encompass a thorough evaluation of the pathology and provide options to the patients in terms of downtime, efficacy, risks, and cost.

Expected benefits and alternatives

The potential for improvement depends upon the device used and depth and degree of injury produced. There are many options for superficial treatment of texture issues, dyschromias, and superficial rhytides including non-aggressive full field resurfacing with Er : YAG, carbon dioxide, YSGG, or plasma devices or with non-ablative or ablative fractional treatment. Many practitioners are using combination therapy with superficial full field treatment combined with fractional treatment, whereas others are combining fractional ablative and non-ablative therapy and others again are using intense pulsed light therapy combined with resurfacing. Other treatments that may yield similar results for superficial pathologies include light chemical peels such as 15–30% trichloroacetic acid (TCA), intense pulsed light (IPL) devices, and Q-switched lasers (532 nm for dyschromias). We prefer lasers and plasma devices to chemical peels owing to the uniformity and predictability of treatment as the device produces tissue effects with minimal variability from pulse to pulse or patient to patient. The learning curve with lasers is less than with chemical peels due to the predictability of the treatment. Expert chemical peelers may get similar results to laser treatment at a fraction of the laser cost, but years of experience are necessary to achieve consistency of results. Intense pulsed light devices may be used to treat dyschromias and superficial vasculature, but require multiple sessions and do not address textural issues or rhytides. Q-switched lasers (532 nm, 694 nm, and 755 nm) are excellent at removing dyschromias in one session but have resultant erythema that lasts for up to 10 days.

More significant pathology requires deep treatment to achieve results in a single session. There is still a question of whether repeated superficial therapies with ablative fractional devices will achieve similar results to one more aggressive full field session. Deep ablative full field resurfacing may be performed with either erbium or carbon dioxide systems. YSGG in full field mode and plasma devices do not ablate deep enough to treat more significant pathology. Acne scars appear to respond better to fractional therapy than to full field therapy. Alternative treatments may be deeper chemical peels such as phenol or dermabrasion. The authors feel that lasers provide more consistent and reproducible results than chemical peels or dermabrasion.

Lasers and technical overview

As discussed above, current devices used for ablative laser resurfacing include carbon dioxide, Er : YAG, and YSGG lasers, in both full field and fractional modes, and non-ablative devices in a variety of wavelengths including 1440 nm, 1540 nm, 1550 nm, and 1927 nm (Table 7.2). Some machines offer upgradeable expandable platforms where full field devices and fractional devices are available in one machine whereas other companies offer only isolated full field or fractional devices.

Er : YAG full field

The erbium : YAG laser (2940 nm) has an absorption coefficient 10 times greater than the carbon dioxide laser and ablates tissue more efficiently and leaves less residual thermal damage (5–10 µm). There is a linear relationship between energy density (fluence) delivered and tissue ablated with 3–4 µm of tissue removed per J/cm² and multiple passes can be used to produce deeper tissue removal without additive residual thermal injury. This leads to recovery time of deep full field Er : YAG laser resurfacing of 7 days to full epithelialization followed by 3–6 weeks of erythema. Superficial and deep resurfacing can be performed with these devices with increasing results and increasing recovery times with deeper treatments (Figs 7.3 and 7.4). Complications including hypopigmentation were less than with carbon dioxide laser full field resurfacing.

Figure 7.3 Periocular treatment – a 38-year-old female (A) before, and (B) 3 years after full field variable pulse width Er : YAG laser treatment of the lower lids.

Figure 7.4 Perioral treatment – a 60-year-old woman (A) before, and (B) 2 years after full field perioral resurfacing with a variable pulse width Er : YAG laser.

Variable pulse Er : YAG systems allow a shorter ablative pulse followed by longer subablative pulses to create increasing thermal damage. These devices are typically used to achieve carbon dioxide laser like results, but without the long healing times and complications such as hypopigmentation.

Fractional ablative technology

Ablative fractional resurfacing can be performed with carbon dioxide, Er : YAG, and YSGG devices. There are many devices available from many well-known laser manufacturers. Differences in devices are the mode of spot placement – scanning versus stamping, size of holes (width and depth) created, and power output of devices. Differences between fractional carbon dioxide systems, fractional Er : YAG systems, and YSGG systems are similar to their full field counterparts in that the carbon dioxide systems cause leave more residual thermal damage. Newer Er : YAG systems have variable pulse widths, which cause carbon-dioxide-like thermal damage. Re-epithelialization is quicker than with full field ablation and recovery time varies from hours to a few days depending upon depth and density of treatment.

Both ablative fractional and non-ablative fractional devices are used to treat acne and other scars. Multiple treatments are needed and there is no current consensus as to the best technology for this at present. It is very common in our offices to perform combination treatment with superficial full field Er : YAG resurfacing followed by Er : YAG fractional treatment. The superficial Er : YAG treatment improves skin texture and minor irregularities while the fractional treatment is useful for collagen remodeling (Figs 7.5, 7.6).

Figure 7.5 A 68-year-old woman with combination fractional Er : YAG resurfacing and fractional 1540 nm non-ablative resurfacing with total coverage of 55%. Time to epithelialization was 4 days. Duration of erythema was 11 days. (A) Before, and (B) 6 months after treatment.

Figure 7.6 (A, B) This patient had scars of the forehead treated with ablative fractional resurfacing.

As fractional CO₂ treatments have been pushed to higher and higher coverages in an attempt to maximize efficacy, healing times predictably have increased. More importantly, complications such as scarring and hypopigmentation have been observed at coverages in excess of 45%. CO₂ resurfacing histology consistently shows a significant component of tissue ablation and coagulation. Efficacious resurfacing is believed to require a significant component of both. One strategy that has been explored to increase coverage percentage and maximize efficacy involves a combination treatment with ablative Er : YAG fractional and non-ablative fractional exposures in a single treatment session. This provides a component of largely ablative exposure with the fractional Er : YAG treatment and a component of coagulation with the non-ablative fractional treatment. Rather than being spatially overlapped as in a fractional CO₂ microthermal zone, the coagulation and ablation are separated. Coverages up to 65% are routinely applied with only a modest increase in healing time and erythema compared with fractional Er : YAG treatment alone and somewhat less than that reported for fractional CO₂. Advantages of this approach include preservation of the short recovery and low incidence of complications seen with fractional Er : YAG treatments and the potential for significant improvement even in perioral rhytides. Disadvantages include the need for two lasers or a single laser platform that offers both options and the time-consuming nature of the treatments (Fig. 7.7).

Figure 7.7 (A–F) Combination treatment with Er : YAG micropeel and Er : YAG fractional. The healing time is 2–3 days; shown are pre-treatment and immediately, day1, day 2, day 3 and 1 week after treatment.

Overview of treatment strategy

Complications and their treatment

Infection

Infection after laser resurfacing can be viral, bacterial, or fungal. The most well-known complication is due to herpes simplex virus. Many patients have been infected previously and so are carriers. The current recommendation as outlined above is for all patients to be prophylaxed against herpes viral infections. Some patients may avoid taking the anti-viral medications whereas others may experience breakthrough infection (Fig. 7.8). The treatment is early recognition of the infection and treatment with oral antiviral agents. For very severe infections with herpes simplex or zoster intravenous anti-viral medication may be needed.

Figure 7.8 A 40-year-old patient who developed candida infection following laser resurfacing.

Pearl 10

Infection after laser resurfacing can be viral, bacterial, or fungal.

Bacterial infection after laser resurfacing using open treatment is uncommon but with increasing methicillin-resistant Staphylococcus aureus (MRSA) there have been patients who have had infection after laser resurfacing. The treatment is administration of broad-spectrum antibiotics with culture of the skin and targeted antibiotic treatment after culture results are obtained.

True fungal infection is rare, but infection with yeast (Candida albicans) is common (Fig. 7.9). The patient usually presents with an extremely red face with a history of having improvement in the healing and suddenly appearing much redder. Treatment is topical anti-fungal therapy with or without an oral antifungal medication such as fluconazole.

Figure 7.9 Herpes infection following laser resurfacing. Patient failed to take prescribed antiviral medication and noticed these lesions. Patient was treated with valaciclovir 100 mg TID, and responded without scarring.

Erythema

Erythema after laser resurfacing is a normal part of the inflammatory healing process. It is directly related to depth of laser resurfacing and to the amount of thermal damage created. Some patients will experience an amount of erythema disproportionate to the treatment. They may be left untreated for the erythema to resolve spontaneously (which it will) or else they may be treated with mild topical corticosteroids, LED treatments, IPL treatments, or with a vascular laser such as a pulsed dye laser.

Skin eruptions

Skin eruptions due to acne or milia are common following laser resurfacing. They may be due to overocclusion with topical products or to activation of gland function. Acne may be treated with discontinuation of occlusive agents. If this fails, oral antibiotics and / or acne laser treatment with mid-infrared lasers may be used. Milia are treated by nicking the overylying skin with a small-gauge needle and expressing them with a comedo extractor.

Pearl 11

Skin eruptions due to acne or milia are common following laser resurfacing.

Telangiectasia

Increased appearance of telangiectasia after laser resurfacing is common. This is due to eradication of overlying photodamage and unmasking of the vasculature. Treatment is with a vascular laser.

Dermatitis

Two types of dermatitis are seen following laser resurfacing: irritant and allergic. Irritant dermatitis, as mentioned previously, may be due to start of topical skin care treatments such as retinoids too early or too aggressively. Allergic contact dermatitis is due to true allergy, usually to one of the topical agents, but may also be due to one of the oral antibiotics. Treatment for both conditions is discontinuation of the offending agent and application of a mild topical corticosteroid.

Hypopigmentation

This is a dreaded complication of deep laser resurfacing and has been reported both with carbon dioxide and Er : YAG treatments and with full field and fractional treatments. It is not uncommon with deep carbon dioxide resurfacing, with some series reporting up to 70% of patients getting hypopigmentation. It is rare with deep Er : YAG full field resurfacing and very rare with all fractional treatments. There are not many effective treatments, but some have reported improvement with excimer laser therapy. Blending of the noticeable line of demarcation is often helpful (Fig. 7.10).

Figure 7.10 A 49-year-old Asian woman who developed hyperpigmentation following Er : YAG resurfacing.

Hyperpigmentation

Postinflammatory pigmentation (PIH) is a very common problem following laser resurfacing. It is more common in darker skin types and in patients who have had early sun exposure (Fig. 7.11). Prevention as outlined above is key. Treatment is with topical bleaching creams, often combined with retinoids. Failures of this regimen are usually treated with IPL.

Figure 7.11 Hypopigmentation that developed after laser resurfacing.

Pearl 12

Postinflammatory pigmentation (PIH) is a very common problem following laser resurfacing.

Scarring

Scarring after laser resurfacing may occur owing to overly aggressive full field or fractional treatment, infection, or even scratching by the patient. Full field resurfacing is a controlled first-degree or second-degree burn and anything such as infection may convert that controlled second-degree burn into a third-degree burn with resultant scarring. Overaggressive fractional resurfacing may be due to too deep a treatment, or too much density, creating a full field defect when a fractional treatment was intended. We prefer early treatment of thickened areas that appear to be heading towards scarring with potent topical corticosteroids such as a pulsed regimen with clobetasol. Intralesional corticosteroids, intralesional 5-FU, vascular laser or IPL treatment, and fractional lasers have all been used to improve hypertropic scars after laser resurfacing (Fig. 7.12).

Figure 7.12 A 64-year-old woman who developed a hypertrophic scar after laser resurfacing: (A) before, and (B) after treatment with intralesional corticosteroids and IPL.

Slow healing

Slow healing has been reported in some cases with re-epithelialization of many months of up to a year. This has led to hypertrophic scarring. This scenario of slow healing may represent an indolent infection. Patients with this scenario should be cultured and potentially biopsied to determine and underlying cause.

Ectropion

Ectropion is caused by laser resurfacing by tightening of the lower eyelid skin in the face of weak lower eyelid canthal support. A snap test or other measurement of lower eyelid laxity is recommended prior to laser resurfacing. Patients with significant laxity are offered either canthal support surgery (rare) or canthal temporary support (temporary tarsorraphy – common).

Synechia

This is caused by healing of two epidermal surfaces and appears as a line (usually in the lower eyelid). If untreated this may lead to cyst formation. Treatment is to manually stretch the edges of the synechia until the line opens.