Laser Principles

Ablative lasers achieve wrinkle reduction through the use of water as the target chromophore to heat and vaporize tissue. The two main laser wavelengths used for ablative resurfacing, 2940 nm (Er:YAG) and 10,600 nm (carbon dioxide), are well absorbed by water. A third, less frequently used wavelength is 2790 nm (yttrium scandium gallium garnet or YSGG). Figure 29-2 shows the water absorption spectrum and these three ablative resurfacing lasers. Note that the erbium 2940 nm wavelength is at a water absorption peak and is approximately 15 times more highly absorbed by water than CO₂.

FIGURE 29-2 Water absorption spectrum and common ablative skin resurfacing lasers.

Absorbed laser energy has two main effects on tissue: (1) removal of tissue, called ablation, and (2) heat transference to surrounding tissue, called coagulation. Coagulation clinically results in tissue tightening. A controlled amount of coagulation with treatments is, therefore, desirable but too much thermal injury can be associated with complications such as hypopigmentation and scarring. Due to a greater absorption by water, Er:YAG lasers ablate tissue at lower fluences (approximately 1 J/cm²), compared to CO₂ lasers, which require higher fluences to achieve similar ablation (approximately 5 J/cm²). Er:YAG lasers, therefore, cause less thermal damage to the surrounding tissues and have smaller zones of coagulation than CO₂ lasers. Figure 29-3 shows the zones of coagulation around a region of ablation with a CO₂ versus an erbium laser. The amount of ablation and coagulation is controlled by laser fluence and pulse width (see Chapter 19, Aesthetic Principles and Consultation, for a discussion of laser parameters). Ablation is most effectively achieved with short pulse widths and high fluences, whereas coagulation is achieved with longer pulse widths and lower fluences (Figure 29-4). By varying these two parameters, ablative laser devices can independently control the amounts of ablation and coagulation achieved.

FIGURE 29-3 CO₂ and Er:YAG coagulation zones around ablated skin.

FIGURE 29-4 Ablation and coagulation with ablative lasers.

Laser fluence is also a major determinant of the depth of injury with fractional ablative devices, where higher fluences penetrate deeper. Density settings control the percentage of skin that is treated. More aggressive fractional ablative treatments are, therefore, achieved with high fluences and high density parameters. Some fractional devices utilize scanners and computer software to “randomly” deliver pulses within a set pattern so that the pulses are not adjacent to one another. Changing the energy delivery pattern from sequential to nonadjacent pulses allows for high energies to be delivered without the effects of bulk heating.⁷ This is particularly useful with CO₂ devices which cause greater thermal injury.

In summary, fractional ablative laser devices have variable fluences, spot sizes, spot densities, and pulse widths, all of which affect the depth of penetration as well as the degree of ablation and coagulation achieved.⁸ Because these devices are still relatively new, clinical correlation is required to determine how these different parameters impact results, downtime, and side effects.

Patient Selection

Fitzpatrick skin type classification is an important factor in assessing patients for laser resurfacing (see Chapter 19, Aesthetic Principles and Consultation, for skin type classification). The ideal patient has a fair complexion (Fitzpatrick types I through III) with lesions responsive to laser ablation (see the Indications section below). Patients with darker complexions (Fitzpatrick types IV and V) may be treated as well, but must be informed about their higher risk for pigmentary complications and the need for more cautious treatment parameters, which may limit results. Although patients with Fitzpatrick skin type V may be candidates, in reality these patients rarely present with the facial aging signs that patients with lighter skin types complain of, and one rarely encounters such a patient seeking facial resurfacing. It is advisable for providers getting started with fractional ablative resurfacing to limit treatments to lighter skin types (I through III).

It is also very important that patients have realistic expectations regarding results. Fractional ablative laser resurfacing can generally improve wrinkles, however, significant skin laxity and sagging jowls may be better addressed with surgery, such as a facelift. Patients must fully understand the ablative laser postoperative recovery course and agree to comply with the postprocedure instructions. Re-epithelialization following fractional ablative laser treatments typically requires 5 to 7 days. Patients must be able to tolerate this recovery period, and anticipated professional and social obligations should be considered with patient selection and timing of the procedure.

Patients often seek laser resurfacing to improve wrinkles near the lower eyelids and significant improvements may be achieved in this area. However, there are certain contraindications to treatment in this area including prior lower blepharoplasty and poor lower eyelid skin elasticity.

Indications9,10

Ablative laser resurfacing has traditionally been used for patients with more advanced signs of facial aging (Glogau stage IV) including generalized static wrinkles, keratoses, severe dyschromia, sallow color, and coarse pores (see Chapter 19 for a discussion of the Glogau photoaging scale). With the advent of fractional technologies that have more rapid recovery times and fewer risks, ablative laser procedures are being performed in patients with less severe photoaging. Nonetheless, the most common indication today for fractional ablative laser resurfacing is still moderate to severe wrinkles as well as scars.

Although ablative lasers are indicated for treatment of pigmentation, patients presenting with only pigmented lesions without concerns about wrinkles and textural changes, may benefit from other less aggressive options, such as nonablative lasers, which maintain an intact epidermis, have minimal risks and little to no recovery time.

Alternative Therapies

Skin resurfacing can also be accomplished by mechanical exfoliation procedures such as microdermabrasion and chemical peeling treatments which typically penetrate to the epidermis or upper reticular dermis (see Chapter 22, Chemical Peels and Chapter 23, Microdermabrasion). Dermabrasion is a mechanical, “cold steel” method of removing epidermis, papillary, or upper reticular dermis. Dermabrasion and chemical peeling have the advantage of being less expensive than laser resurfacing. However, extensive hands-on experience in a preceptor environment is required in order to learn the art of dermabrasion.¹¹

Products Currently Available

Fractional ablative lasers are a relatively new class of lasers. Three main wavelengths are used for these technologies:

See the Resources section at the end of the chapter for a list of manufacturers of devices that have these wavelengths.

Contraindications

See the General Laser Contraindications section in Chapter 26, Hair Reduction with Lasers. Additional contraindications include the following:

Advantages of Laser Resurfacing

Disadvantages of Laser Resurfacing

Anatomy

Superficial nonfractionated ablative laser treatments typically wound and remove the epidermis (up to 50 µm or 0.05 mm). Deep nonfractionated ablative laser treatments typically wound the papillary and upper reticular dermis (up to 300 µm or 0.3 mm) and remove the entire epidermis. Fractional ablative lasers penetrate into the deep reticular dermis (up to 1500 µm or 1.5 mm) and remove a portion of the epidermis.

Equipment

Anesthesia—Intraoral Nerve Blocks

Anesthesia—Topical

Anesthesia—Assistive External Device

See Chapter 20, Anesthesia for Cosmetic Procedures, and Chapter 3, Anesthesia, for more information.

Procedure

Postprocedure

Procedure Preparation

The following guidelines are based on fractional ablative laser resurfacing treatments for Fitzpatrick skin types I through III. Manufacturer guidelines for the specific device used should be followed at the time of treatment.

Fractional Ablative Laser Resurfacing: Steps and Principles

The following guidelines are based on treatments of the full face using a fractional ablative erbium 2940 nm laser (Hoya ConBio DermaSculpt™), which is indicated for Fitzpatrick skin types I through III. Manufacturer guidelines for the specific device used should be followed at the time of treatment.

Planning and Designing

Ablative laser resurfacing may be performed to a region of the face or to the entire face. Figure 29-5 shows three of the most commonly treated facial aesthetic subunits (modified from Gonzales-Ulloa¹⁶). The periocular subunit is bounded inferiorly by the crest of the zygoma and superiorly by the orbital rim. The upper lip subunit extends laterally to the nasolabial folds and superiorly to the nose. The chin subunit extends along the line of the nasolabial fold inferiorly, below the jaw line. The perioral subunit includes the upper lip and chin subunits.

FIGURE 29-5 Fractional Ablative Laser Resurfacing Safety Zone and common facial aesthetic subunits treated.

Performing Fractional Ablative Laser Resurfacing

1. Position the patient supine with the treatment table flat. The physician should be seated in a comfortable position relative to the patient.

2. Remove all topical anesthetic.

3. Prepare the skin with an alcohol or astringent.

4. Provide appropriate laser eye protection for the patient and all personnel in the treatment room prior to beginning treatment.

5. Always operate the laser in accordance with your office’s laser safety policies and the manufacturer’s guidelines.

6. Before treatment, direct a test spot to a tongue depressor to confirm laser functioning as well as desired treatment pattern and density.

7. Have the assistant position the smoke evacuator near the area to be treated, approximately 3 to 4 inches above the skin (Figure 29-6).

FIGURE 29-6 Clinical endpoints for fractional ablative resurfacing with crisp white laser spots and background erythema. Smoke evacuator postition is also shown.

(Copyright Rebecca Small, MD.)

TIP: Take care to avoid contacting the skin with the smoke evacuator because this makes a loud noise and can be startling. Also take care not to bump the laser.

8. Perform a single pulse near the lateral margin of the treatment area and assess for patient tolerance and clinical endpoints (see below).

9. Desirable clinical endpoints include:

• White dots in the shape selected (Figure 29-6)

• Background erythema (Figure 29-6)

• Pain level less than or equal to 6 on a scale of 1 to 10.

10. Pinpoint bleeding (Figure 29-7) may be evident with aggressive treatments.

FIGURE 29-7 Clinical endpoints for fractional ablative resurfacing of pinpoint bleeding and erythema.

(Copyright Rebecca Small, MD.)

TIP: Lasers used with pure ablation and no coagulation are more likely to cause bleeding.

11. Adjust laser settings based on observations of laser/tissue interaction, clinical endpoints, and patient discomfort throughout treatment.

12. Perform treatment of the entire area.

13. When treating near the jaw line, extend treatment under the jaw (Figure 29-8).

14. Blend the treatment area with adjacent untreated areas by reducing settings around the periphery of the treated area.

15. Upon completion of the treatment, patients are often uncomfortably hot and it is important to cool them down rapidly. Carefully apply wrapped ice packs to the face and/or use a cool air blower.

16. Apply an occlusive topical ointment to the treatment area (such as SkinCeutical’s Primacy).

FIGURE 29-8 Ablative laser treatments on the lower face extend under the jaw line.

(Copyright Rebecca Small, MD.)

Results

Fractional ablative lasers (CO₂ and Er:YAG) can significantly improve wrinkles and hyperpigmentation in photoaged skin.^4,5,18–20 Wrinkle reduction can be seen in the immediate post-treatment period, once re-epithelialization occurs, and continues to improve up to 6 months after treatment. The presumed mechanism for textural improvement is through thermally induced collagen denaturation and shrinkage immediately after treatment, with delayed fibroblast proliferation and synthesis of new collagen, also called dermal collagen remodeling.²¹

Laser resurfacing also plays an important role in reduction of scars. Blending scar borders with the surrounding skin, and improving pigment changes in the scar can help achieve excellent camouflage. Fractional ablative lasers have showed success with scar reduction, primarily atrophic acne scars.^22,23

Figure 29-9 shows the results of deep ablative laser resurfacing for facial wrinkles (A) before and (B) after one treatment using an erbium laser to a 120 µm depth (Sciton Contour TRL™).

FIGURE 29-9 Deep ablative laser resurfacing for facial wrinkles (A) before and (B) after one treatment to a 120-µm depth with an erbium laser.

(Courtesy of L. Apostolakis, MD, using Sciton Contour TRL™.)

Figure 29-10 shows the results of fractional ablative laser resurfacing for facial wrinkles (A) before and (B) after one treatment using a carbon dioxide laser (Fraxel Re:pair™).

FIGURE 29-10 Fractional ablative laser resurfacing for facial wrinkles (A) before and (B) after one treatment with a carbon dioxide laser.

(Courtesy of Z. Rahman, MD, using Fraxel Re:pair™.)

Figure 29-11 shows the results of fractional ablative laser resurfacing for facial wrinkles and pigmentation (A) before and (B) after one treatment using a carbon dioxide laser (Fraxel Re:pair™).

FIGURE 29-11 Fractional ablative laser resurfacing for facial wrinkles and pigmentation (A) before and (B) after one treatment with a carbon dioxide laser.

(Courtesy of Z. Rahman, MD, using Fraxel Re:pair™.)

Figure 29-12 shows the results of fractional ablative laser resurfacing for perioral wrinkles (A) before and (B) after one treatment using a carbon dioxide laser (Lumenis TotalFX™).

FIGURE 29-12 Fractional ablative laser resurfacing for perioral wrinkles (A) before and (B) after treatment with a carbon dioxide laser.

(Courtesy of G. Munavalli, MD, using Lumenis TotalFX™.)

Figure 29-13 shows the results of fractional ablative laser resurfacing for facial wrinkles (A) before and (B) after one treatment using an erbium laser (Sciton Profractional-XC™).

FIGURE 29-13 Fractional ablative laser resurfacing for facial wrinkles (A) before and (B) after one treatment with an erbium laser.

(Courtesy of K. Remington, MD, using Sciton Profractional-XC™.)

Figure 29-14 shows the results of fractional ablative laser resurfacing for periocular wrinkles (A) before and (B) after one treatment using an erbium laser (Palomar Lux2940™).

FIGURE 29-14 Fractional ablative laser resurfacing for periocular wrinkles (A) before and (B) after one treatment with an erbium laser.

(Copyright Rebecca Small, MD, using Palomar Lux2940™.)

Figure 29-15 shows the results of fractional ablative laser resurfacing for acne scarring (A) before and (B) after five treatments using an erbium laser (Sciton Profractional-XC™).

FIGURE 29-15 Fractional ablative laser resurfacing for acne scarring (A) before and (B) after five treatments with an erbium laser.

(Courtesy of K. Remington, MD, using Sciton Profractional-XC™.)

Figure 29-16 shows the results of fractional ablative laser resurfacing for actinic keratoses (A) before and (B) after two treatments using an erbium laser (Sciton Profractional™).

FIGURE 29-16 Fractional ablative laser resurfacing for actinic keratoses (A) before and (B) after two treatments with an erbium laser.

(Courtesy of R. Koch, MD, using Sciton Profractional™.)

Figure 29-17 shows the results of superficial ablative laser resurfacing for solar lentigines (A) before and (B) after one treatment using an erbium laser to a 50-µm depth (Sciton Contour TRL™ MicroLaserPeel™).

FIGURE 29-17 Superficial ablative laser resurfacing for solar lentigines (A) before and (B) after one treatment to a 50-µm depth with an erbium laser.

(Courtesy of J. Pozner, MD, using Sciton Contour TRL™ MicroLaserPeel™.)

Figure 29-18 shows the results of precision ablative laser resurfacing for seborrheic keratoses (A) before and (B) after one treatment using an erbium laser (HOYA ConBio Dermasculpt™ Chisel Touch™).

FIGURE 29-18 Ablative laser resurfacing for seborrheic keratoses (A) before and (B) after one treatment with an erbium laser microtip.

(Courtesy of K. Khatri, MD, using HOYA ConBio Dermasculpt™ Chisel Touch™.)

Aftercare

Fractional ablative laser treatments have two distinct phases of healing:

The open wound stage starts from the time of treatment and persists until full re-epithelialization takes place. This typically takes 4 to 7 days, with erbium lasers trending toward shorter recovery times.²⁴ Figure 29-19 shows the recovery process for a fractional ablative erbium laser resurfacing treatment on the face of a 41-year-old woman 1 day postprocedure (Figure 29-19A), where the treatment area is an open wound with intense erythema, some serous oozing, crusting, and pinpoint bleeding. By the fourth postprocedure day (Figure 29-19B), the treatment area is almost fully re-epithelialized, showing mild erythema with a few open areas. On day 5, this patient had fully re-epithelialized.

FIGURE 29-19 Recovery process for fractional ablative erbium laser resurfacing on (A) the first postprocedure day and (B) the fourth postprocedure day.

(Copyright Rebecca Small, MD.)

Open wound care consists of gentle rinsing of the treatment area with dilute acetic acid (vinegar) soaks several times a day (see the patient information handout titled Fractional Ablative Laser Resurfacing in Appendix A). Some providers alternatively use gentle facial rinsing with warm soapy water several times a day. Figure 29-20 shows a patient the day after fractional ablative erbium resurfacing (A) prior to and (B) immediately after a vinegar cleanse. Note the devitalized, brown tissue and crusting has been removed to reveal healthy pink tissue after cleansing. Pinpoint bleeding may occur during the cleansing process, which is not undesirable. Cleansing is followed by application of an occlusive ointment such as Aquaphor, Crisco,²⁵ or Primacy to promote moist wound healing. Some providers use nonocclusive products that promote wound healing, such as Biafine, during this phase.²⁶ Excessive or prolonged use of occlusive topical products may increase the risk of milia, folliculitis, acne, and bacterial or candidal infections, whereas too little product may result in crusting and delayed re-epithelialization. During the open wound phase, no sunscreen or makeup is worn and strict sun avoidance is imperative to reduce the risk of hyperpigmentation.

FIGURE 29-20 Perioral fractional ablative resurfacing on the first postprocedure day (A) prior to and (B) immediately after cleansing with vinegar solution.

(Copyright Rebecca Small, MD.)

The postepithelialization stage commences once the open wound has healed and the epidermis is fully intact. This stage typically starts 1 week postprocedure and persists for 3 weeks. Skin is mildly erythematous and more sensitive than at baseline. Occlusive products are discontinued and products that are nonirritating and reparative, such as SkinCeutical’s Epidermal Repair, may be used in addition to sunscreen. Mineral makeup may be applied at this time to camouflage any remaining erythema.

It is advisable to avoid aesthetic procedures such as chemical peels, microdermabrasion, dermaplaning, waxing, and lasers for 2 months after the initial treatment, unless necessary for management of a complication such as hyperpigmentation. Dermal filler treatments may be performed 1 month after resurfacing and botulinum toxin treatments 2 weeks after resurfacing. When skin is no longer sensitive, patients’ preprocedural rejuvenation products may be resumed.

See the Preprocedure and Postprocedure Products section in Chapter 24, Skin Care Products, for more information about postprocedure skin care.

Follow-Up

Regular, frequent follow-up is advised initially to monitor the healing progress as well as to identify any early complications.²⁷ During the open wound phase in the first week, it is recommended that the patient be seen on postprocedure day 1 or 2, to evaluate the wound and ensure adherence to proper home care. A visit at 1 week is recommended to assess for full re-epithelialization, and once this is observed, the postepithelialization stage has begun and the patient may be transitioned to nonocclusive postcare topical products. If recovery is uneventful, the follow-up schedule may be 1 month and 3 months postprocedure. Any concerns or problems warrant more frequent visits.

Complications

Despite the advances of fractional technologies that have increased safety and shortened recovery with ablative lasers, clinicians must remember that fractional ablative lasers can be associated with complications. An open wound is created with these treatments and complications such as infection and scarring can and do occur. Most of the complications with fractional ablative lasers to date have been reported in thin-skinned areas, such as under the eye, and in nonfacial areas, such as the neck.²⁷ Early recognition of complications allows the physician to initiate appropriate treatments that can help reduce the risk of permanent damage. The following discussion reviews complications and management of complications reported with ablative laser treatments, with fractional and nonfractional devices.

Adverse effects after ablative laser resurfacing range from mild to severe. Prolonged erythema, acne or milia formation, contact dermatitis, and pruritus are examples of mild reactions. Moderate complications include infections and postinflammatory hyperpigmentation. More serious complications include hypertrophic scarring, delayed onset hypopigmentation, ectropion, and disseminated infection.

Pain is usually transient, present only during treatment or for 20 to 30 minutes afterwards. Delayed postprocedure pain requires evaluation and may be associated with infection.

Bleeding may be apparent with cleansing during the open wound stage and resolves within 1 to 2 days postprocedure. It is usually evident as tiny pinpoint hemorrhages that rapidly become hemostatic and do not require bandaging.

Erythema and edema are normal signs after laser resurfacing and are considered abnormal if they persist longer than the expected period. Postprocedure erythema after re-epithelialization is usually mild in intensity and is resolved by 1 month. By comparison, nonfractional deep ablative lasers routinely resulted in prolonged erythema for 3 to 6 months after treatment. In general, postoperative erythema following CO₂ laser treatments lasts longer than with erbium lasers, due to the greater thermal damage from CO₂. Prolonged erythema lasting past 1 month and intense erythema lasting past 1 week should be considered unusual and addressed. Persistent erythema may indicate impending scar formation or may be due to contact dermatitis to topical compounds used during the recovery phase. If an impending scar is suspected, a strong class I topical corticosteroid should be applied¹² (see the discussion of hypertrophic scarring later in this section for additional scar therapies). If contact dermatitis is suspected, all topical medications should be discontinued and topical corticosteroids used. A history of rosacea may predispose to persistent postoperative erythema.^12,28

Postoperative contact dermatitis is usually irritant in nature.^31–33 Newly resurfaced skin is vulnerable to irritation from various substances found in topically prescribed ointments, preservatives, sunscreens, and fragrances. In addition, topical antibiotics such as bacitracin, Neosporin (bacitracin zinc, neomycin sulfate, and polymyxin B sulfate), and Polysporin (bacitracin zinc and polymyxin B combinations) are common sources of irritation after laser resurfacing. Thus, their use should be avoided in the immediate postoperative period. Finally, many patients may self-prescribe various over-the-counter herbal and vitamin remedies, including vitamin E or aloe products, which can contribute to the problem. Contact dermatitis should be suspected if a patient develops worsening erythema or pruritus after treatment. To decrease this risk, moisturizers without active ingredients should be used during the first postoperative month. If contact dermatitis is suspected, all topical agents should be stopped and mild topical corticosteroids and cool, wet compresses applied regularly. In severe cases, oral antihistamines or short courses of oral corticosteroids may be necessary to control inflammation and reduce fibrosis risk.

Acne flare-ups are relatively common after laser resurfacing due to application of occlusive ointments, especially in patients who are acne prone.^29–31 These usually develop within the first few weeks in patients with a strong history of acne, and in other patients may be delayed. Often, no treatment is necessary since the flare-ups are usually mild and resolve once ointments are discontinued. If acne persists despite the discontinuation of occlusive ointments, an oral antibiotic such as doxycycline or minocycline may be used or topical antibiotics such as clindamycin may be used with fully re-epithelialized skin.

Milia, which appear as tiny 1 to 2-mm white papules, result from occlusion of sebaceous glands. Use of occlusive moisturizers, such as petrolatum-based products, frequently cause milia. Milia may be treated one skin is intact skin, by lancing with a 20-gauge needle and extracting the sebaceous plug, 1 to 2 months postprocedure.

Alteration of dermal filler may occur after ablative laser treatment, particularly with hyaluronic acid fillers. It is advisable to avoid treatment over facial areas that have hyaluronic acid fillers.

Infections can be viral, bacterial, or fungal and usually develop during the first postoperative week.³⁴ The appearance of infections in nonintact resurfaced skin does not always have the characteristic signs seen with intact skin. It is advisable for providers to have a low threshold for culturing areas suspected of infection.

The most frequent infectious complication following ablative laser resurfacing is reactivation of herpes simplex virus (HSV), reported in 2% to 7% of patients, even in those who receive antiviral prophylaxis.^35,36 Because there is a high incidence of latent HSV infection, many providers use prophylaxis with all patients undergoing facial laser resurfacing with oral antiviral medications. Acyclovir, famciclovir, or valacyclovir is routinely given 2 days before laser treatment and continued for another 3 to 10 days. Symptoms of HSV infection include tingling, burning, or discharge from isolated areas in the treated areas. Characteristic grouped vesicles may be difficult to recognize in the early postoperative period because there is no intact epithelium. Instead, one may see small superficial erosions. If a herpetic outbreak occurs despite prophylaxis, consider switching to a different antiviral medication or increase the dosage to maximal herpes zoster doses (acyclovir 800 mg 5 times a day, or famciclovir/valacyclovir 500 mg 3 times a day).

Bacterial and fungal infections can also occur because the moist environment of resurfaced skin presents an ideal medium for overgrowth of opportunistic pathogens. The most common bacterial infections are streptococcal, staphylococcal, or Pseudomonas aeruginosa. Fungal infections can be difficult to diagnose because they may resemble acne or milia in nonintact skin. Pain, increased erythema, purulent discharge, crusting, or delayed wound healing should alert one to possible bacterial or fungal infections. It is advisable to obtain wound cultures and initiate antibiotics against the common pathogens prior to obtaining culture results. Infections must be treated aggressively since local spread can lead to permanent scarring, significant morbidity and in severe cases can become disseminated infections. Some providers routinely use antibiotics as part of their perioperative regimen. However, there is no evidence supporting this practice, and indiscriminate antibiotic use may favor drug resistance and promote superinfection by other opportunistic pathogens.³⁷

Postinflammatory hyperpigmentation may develop as postprocedure erythema resolves. It is usually seen within the first month postprocedure and spontaneously resolves during the next several months. Various treatments can be initiated to speed this resolution. Topical agents such as retinoic, azelaic, and glycolic acid compounds, hydroquinone preparations, or light glycolic acid peels (e.g., 30% to 40%) can be used after the first postoperative month.¹² It is also important to continue application of a broad-spectrum sunscreen (SPF 30 or higher) to help prevent and limit hyperpigmentation worsening.

Delayed onset hypopigmentation is a potentially serious and permanent complication that has been reported with ablative laser resurfacing.³⁸ Figure 29-21 shows a patient with hypopigmentation 20 years after receiving nonfractional deep ablative CO₂ resurfacing of the face. Hypopigmentation usually does not present until 6 to 12 months after ablative laser resurfacing. While relative hypopigmentation in certain areas such as the jaw line may be seen infrequently, true hypopigmentation is rare and occurs more often in patients receiving other forms of aggressive resurfacing such as dermabrasion or phenol peeling. To date, there are no reports of isolated hypopigmentation with fractional ablative resurfacing unless scarring has occurred.²⁷

FIGURE 29-21 Hypopigmentation complication 20 years after ablative CO₂ resurfacing of the face.

(Copyright Rebecca Small, MD.)

The treatment strategy for hypopigmentation is to reduce the contrast between the hypopigmented treatment area and adjacent skin by using chemical peels or nonablative lasers to decrease the surrounding skin’s relative hyperpigmentation. Opaque makeup may be used for camouflage.

Hypertrophic scarring is an uncommon but serious complication. Factors increasing the risk for hypertrophic scarring include poor technique with overly aggressive laser parameters including high fluences, pulse stacking, excessive pulse overlapping, and high number of passes. Certain locations such as the lower eyelids, mandible, anterior neck, and chest are more susceptible to scarring and should be treated cautiously.^27,39 Postoperative contact dermatitis or wound infection can also lead to scarring if not treated appropriately. Finally, recent use of isotretinoin, previous irradiation, and a history of keloid formation can increase scarring risk.⁴⁰ Scarring is heralded by focal areas of intense erythema and induration. Early intervention is critical to avoid permanent scarring. Strong class I topical corticosteroids should be applied. Intralesional corticosteroid injections, silicone gel sheeting, and use of the pulsed dye lasers (585 nm) are other treatment options.

Ectropion is another serious complication following laser resurfacing. Prior lower blepharoplasty increases this risk, as does lower lid laxity, which must be ruled out with a “snap test” (see the Procedure Preparation section earlier in this chapter) prior to laser resurfacing. If lower lid laxity exists, it is advisable to avoid laser resurfacing near the lower lid. In general, conservative laser settings and fewer laser passes are employed when treating the lower lids due to the thin nature of the skin. Although topical corticosteroid application, massage, and temporary taping may be tried if ectropion results, often surgical correction is required.

Ocular injury can be avoided by wearing appropriate laser-safe eyewear at all times during treatment, directing the laser tip away from the eye, and treating outside of the eye orbit.

Treating Specific Lesions/Areas

Learning the Techniques

The technique for placement of fractional ablative pulses can be practiced on an eggplant because the white pulse pattern will be clearly visible.

Financial Considerations

Ablative laser resurfacing is not reimbursable by insurance. The charges for treatments vary and are mainly determined by local prices. For example, fees for fractional ablative laser resurfacing in the Northern California Bay Area range from $1800 to $4500 for full face and $800 to $1200 for periocular or perioral areas. Box 29-1 lists applicable codes for ablative laser procedures.

Conclusion

In properly selected patients, fractional ablative laser resurfacing is an excellent choice for the treatment of moderate to severe photoaged skin, particularly for static rhytids. This novel method of delivering laser energy to the skin has resulted in dramatically reduced recovery times and minimal postprocedure complications relative to other ablative technologies. This technology offers the clinician great flexibility in skin resurfacing with its customizable treatment parameters. Fractional ablative lasers are a relatively new class of laser, and as knowledge of tissue effects with specific laser parameters expands, the performance and side effect profiles of these devices are likely to continue improving.

Resources