Laser Principles

Laser treatments are based on the principle of selective photothermolysis. Light-absorbing pigments in the skin, called chromophores, selectively absorb light energy and convert it to heat in the targeted lesions. The lesions are heated, damaged, and eliminated, while the surrounding skin is left unaffected. Photorejuvenation treatment of benign pigmented and vascular lesions is achieved through selectively targeting two main chromophores in the skin, oxyhemoglobin, which is found in red blood, and melanin, which is found in pigmented lesions.⁶

When treating red vascular lesions, laser energy is absorbed by the oxyhemoglobin chromophore. The vessel is heated, causing injury to the vessel wall and perivascular collagen damage, which results in vessel closure and obliteration. Oxyhemoglobin absorbs light between 510 and 600 nm (Figure 27-1). Lasers used for the treatment of red vascular lesions produce light in this range and include argon (510 nm), potassium titanyl phosphate or KTP (532 nm), and pulsed dye (585 nm) lasers.

FIGURE 27-1 Absorption spectra of tissue chromophores and lasers commonly used for photorejuvenation.

When treating benign pigmented lesions, such as lentigines, light energy is absorbed by the target chromophore melanin that is contained within the melanosomes of epidermal melanocytes and keratinocytes. The melanosome is heated, ruptured, and the melanin eliminated. Melanin preferentially absorbs light between 650 and 1100 nm (see Figure 27-1). Lasers used for treatment of epidermal pigmented lesions produce light in this range and include ruby (694 nm), alexandrite (755 nm), diode (810 nm), and neodymium-doped yttrium aluminum garnet or Nd:YAG (1064 nm) lasers. The light from KTP (532 nm) and argon (510 nm) lasers has high absorption by both melanin and oxyhemoglobin and can be used to treat both pigmented and vascular lesions.

Intense pulsed light (IPL) devices emit a spectrum of wavelengths, and certain desired wavelengths can be selected with the use of filters. For example, some IPL filters have an emission peak from 500 to 670 nm and a second emission peak from 870 to 1200 nm. Melanin and oxyhemoglobin are targeted with these wavelengths. In addition, lesions at different depths are also targeted because the shorter wavelengths target more superficial lesions and the longer wavelengths target deeper lesions. In this way, a single IPL device can be used to target both vascular and pigmented lesions at a variety of depths in the skin.

Several device parameters affect the safety and efficacy of photorejuvenation treatments. These parameters include wavelength, fluence, pulse duration, and spot size (see Laser Parameters in Chapter 19, Aesthetic Principles and Consultation).

FIGURE 27-2 Common benign lesions in photoaged skin.

Patient Selection

Patients with fair skin (Fitzpatrick skin types I through III) are the best candidates for photorejuvenation treatments because this population presents with the greatest contrast between background skin and target lesions. Both benign vascularities and hyperpigmentation are common complaints in patients with light skin types. Photodamaged skin characteristically shows midface erythema and peripheral lentigines (see Figure 19-1 in Chapter 19).

Patients with darker skin (Fitzpatrick skin types IV through VI) have increased risks of complications such as hyperpigmentation, hypopigmentation, and burns due to melanin in the background skin competing with chromophores in the target lesions. Hyperpigmentation and melasma are common complaints in patients with darker skin types. The safest devices for treatment of hyperpigmentation in these patients are Q-switched Nd:YAG (1064 nm) lasers, and it is advisable for treatments to be performed by providers experienced with darker skin types.

Indications

Patient Expectations

Photorejuvenation of benign pigmented and vascular lesions may be performed on virtually any body region where photodamage is present. The face, neck, chest, and hands are some of the most commonly treated areas. Noticeable results are evident with a single treatment in properly selected candidates, but typically a series of three to five IPL treatments is required for dramatic improvements.⁴ Treatment with lasers may require a fewer number of treatments than with IPL devices. Larger red facial vessels, which have more chromophore target, usually respond more dramatically than smaller lacy red vessels or diffuse erythema. Discreet lesions such as cherry angiomas typically resolve with no recurrence after one or two treatments.

Alternative Therapies

Nonlaser treatment options for benign pigmented lesions include liquid nitrogen, exfoliation treatments such as microdermabrasion and chemical peels, and topical skin-lightening products such as hydroquinone. Liquid nitrogen can achieve reduction in pigmentation, however, it is frequently associated with hyperpigmentation and hypopigmentation and it is advisable to restrict use to lighter skin types for this reason. Exfoliation and topical therapies are slower to achieve improvements and results are rarely comparable to those seen with lasers. More aggressive laser treatments with longer recovery times and greater risks of complications, such as ablative carbon dioxide and erbium lasers (fractionated and nonfractionated), are also indicated for pigmented lesions. Electrosurgery may be used for some vascular lesions, although this may scar (see Chapter 14, Electrosurgery). Photodynamic therapy (PDT), utilizing topical photosensitizing medication activated by light, has also been used for photorejuvenation (see the Current Developments section below).

Products Currently Available^7–11

Lasers commonly used for treatment of red vascular lesions include the following:

Lasers commonly used for treatment of pigmented lesions include these:

Ruby (694 nm) and argon (510 nm) lasers were some of the first lasers used for photorejuvenation, but due to their short wavelengths and high melanin absorption, they have a high incidence of hypopigmentation and are rarely used today. Q-switched ruby lasers are still used for tattoo removal.

See the Resources section at the end of this chapter for laser manufacturers.

Contraindications

See Chapter 26, Hair Reduction with Lasers, for general laser contraindications. Other contraindications include:

Advantages of Photorejuvenation

Laser photorejuvenation offers dramatic improvements in a relatively short amount of time compared to topical products such as retinoids or hydroquinone. Compared to more aggressive treatments such as fractional and nonfractional ablative carbon dioxide and erbium lasers, the recovery time is minimal and the risks of complications such as hyperpigmentation, hypopigmentation, scarring, or infection are minimal. Although liquid nitrogen is a less expensive option for treating hyperpigmentation, it has a greater risk of hypopigmentation than photorejuvenation lasers.

Disadvantages of Photorejuvenation

Proper precautions need to be taken during laser treatments to avoid alteration to tattoos and permanent makeup. Photorejuvenation treatments for patients with darker Fitzpatrick skin types (IV and higher) have increased risks of hyperpigmentation, hypopigmentation, and scarring. The initial cost of laser technologies is a disadvantage.

Anatomy

Benign pigmented lesions, such as lentigines, and benign vascular lesions, such as telangiectasias, are some of the most common lesions evident in photodamaged skin. Figure 27-2 shows the relative location of these lesions in the skin, with lentigines in the epidermis and telangiectasias in the dermis.

Telangiectasias are these cutaneous vessels that range in size from 0.1 to 1.0 mm. The three main types linear, arborizing and spider, are shown in Figure 27-3. Telangiectasias that arise from dilated arterioles are bright red with small diameters; those from venules are bluish in color with larger diameters; and those from capillaries are fine lacy red vessels or appear as background erythema to the naked eye.¹² Red facial telangiectasias seen with photoaging are commonly located in the midface on the nasal ala and dorsum of the nose and cheeks. Telangiectasias may also be associated with clinical conditions such as rosacea, genetic syndromes, and collagen vascular diseases (Box 27-1).

FIGURE 27-3 Telangiectasia types (A) linear, (B) arborizing and (C) spider.

Solar lentigines are small brown macules that increase in size and number with chronic sun exposure and are typically located around the periphery of the face (see Figure 27-8A later in the chapter). Postinflammatory hyperpigmentation can be seen in susceptible individuals, typically darker skin types (Fitzpatrick IV through VI), as brown macules arising at sites of previously inflamed acne lesions or sites of wound healing (see Figure 24-6A in Chapter 24, Skin Care Products). Melasma presents as hyperpigmented reticulated patches and brown macules, typically on the cheekbones, upper lip, forehead, and chin (see Figure 27-13A later in this chapter). It is frequently observed following a change in female hormonal status such as during pregnancy (chloasma) or after initiating use of oral contraceptives.

Cutaneous pigmented lesions may be located in the epidermis, dermis, or in both. Solar lentigines and ephelides (freckles) are located in the epidermis. Postinflammatory hyperpigmentation and melasma may be located in any of these levels. A Wood’s lamp can be used to determine the depth of melanin pigmentation in the skin.¹³ Epidermal pigmentation appears darker with more contrast against the background skin under Wood’s lamp illumination, whereas dermal pigmentation has less contrast.

Equipment

Procedure Preparation

Laser Photorejuvenation: Steps and Principles

The following recommendations are guidelines for photorejuvenation treatments using an IPL device (Palomar StarLux 500 using the LuxG handpiece) for Fitzpatrick skin types I through IV. Manufacturer’s guidelines for the specific device used should be followed at the time of treatment.

Planning and Designing

Figure 27-4 shows a recommended sequence for IPL treatment of the full face, starting with area 1 and progressing to area 6. The direction of IPL pulses is toward the provider as shown in Figure 27-5, with approximately 20% overlap of each pulse. The amount of pulse overlap may vary with different laser devices.

TIP: The laser tip is always angled away from the eyes during treatment.

TIP: The most sensitive areas are the upper lip (philtrum) and lateral to the nose. To reduce discomfort when treating the upper lip have the patient place his or her tongue over the teeth while keeping the lips closed.

CAUTION: It is advisable to avoid dark coarse facial hair, such as men’s beards. Treating over darkly colored hair will singe hair and may permanently reduce hair growth or result in overtreatment of the epidermis with blistering.

FIGURE 27-4 Treatment sequence for IPL photorejuvenation of the face.

(Copyright Rebecca Small, MD.)

FIGURE 27-5 Handpiece direction for IPL photorejuvenation treatment of the face.

(Copyright Rebecca Small, MD.)

Performing the Photorejuvenation Procedure

1. Inquire about sun exposure and sunscreen use at every visit. If the patient is recently sun exposed or has tanned skin in the treatment area, it is advisable to wait 1 month before treating to reduce the risk of complications.

2. Position the patient supine on a flat procedure table.

3. Cleanse the skin with a nonalcohol wipe.

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

5. Cover tattoos and permanent makeup with wet gauze and keep the laser tip at least 1 inch away from the tattoo during treatment.

6. Operate the laser in accordance with your clinic’s laser safety policies and procedures and the manufacturer’s guidelines.

7. Apply a clear colorless laser gel to the skin, spreading to a thin 1- to 2-mm layer or as directed per the manufacturer’s guideline.

8. Place the laser tip firmly on the skin, making certain that the entire tip is in contact with the skin.

TIP: When treating vascular lesions, avoid excessive downward pressure on the skin because this will blanch vessels, diminishing the target for the laser and may reduce treatment efficacy.

9. Perform a single pulse at the lateral margin of the treatment area and assess for patient tolerance and clinical endpoints (see below). In general, there should be subtle endpoints during initial treatments with a pain score less than or equal to 6 on a scale of 1 to 10.

10. Desirable clinical endpoints for pigmented lesions, such as lentigines, include:

• Darkening of the lesion and enhanced demarcation against the background skin (Figure 27-6B)

• Mild perilesional erythema (Figure 27-6B)

• Gray or black discoloration of the lesion, which can occur with aggressive treatment.

TIP: Endpoints evolve rapidly with more aggressive settings of shorter pulse widths and higher fluences. Longer pulse widths typically have a delayed appearance of endpoints of up to several minutes.

TIP: Clinical endpoints are more evident with lighter Fitzpatrick skin types (I through III) than darker skin types (IV).

Figure 27-6A shows a patient’s chest immediately after laser treatment of lentigines on the right half of the chest. The close-up view of the treated chest area (Figure 27-6B) shows endpoints of lesion darkening, demarcation, and perilesional erythema, as compared to the untreated areas (Figure 27-6C).

11. Desirable clinical endpoints for red vascular lesions, such as telangiectasias, include:

• Spontaneous blanching

• Darkening with a grayish discoloration

• Mild surrounding erythema

• No apparent change. If no change is apparent, compress the vessel and observe for blanching and refilling. An adequately treated vessel will not blanch, whereas partially treated vessels will refill sluggishly.

• Purpura/bruise (see Figure 27-16 later in the chapter). In rare instances, short pulse widths and high fluences may cause a vessel to rupture, resulting in purpura. Purpura is an aggressive endpoint with IPL. Patients must be reassured and informed that resolution can take up to 2 weeks.

12. Desirable clinical endpoints for cherry angiomas include:

• Purplish discoloration. These lesions gradually regress and fade in size and color over time.

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

14. The entire treatment area is covered with laser pulses, using the appropriate amount of overlap.

15. At subsequent visits, fluence is increased and pulse width decreased, according to the manufacturer’s guidelines, to target lighter pigmentation and finer vessels. Typically, only one parameter is changed to intensify treatments at any given visit.

TIP: Delay treatment by 2 weeks if microcrusts from the previous treatment are visible.

16. After treatment, apply ice for 15 minutes to minimize erythema, edema, and reduce discomfort.

17. If the treatment area is erythematous, 1% to 2.5% hydrocortisone cream may be applied.

18. A full-spectrum sunscreen (SPF 30 with zinc or titanium) is applied to sun-exposed areas.

FIGURE 27-6 IPL photorejuvenation of the right chest (A) immediately after treatment. Close-up views show (B) lentigo clinical endpoints of lesion darkening, border demarcation and perilesional erythema, as compared to (C) the untreated area.

(Copyright Rebecca Small, MD.)

Results

Results of an initial photorejuvenation treatment with IPL for lentigines on the chest of a 36-year-old patient are shown in Figure 27-7. The patient’s chest is shown prior to treatment in (A) 1 week after treatment in (B), and 2 weeks after treatment in (C). Note in (B) the darkened and flaking appearance of the lentigines 1 week after treatment due to microcrust formation and the significant improvement in pigmentation at 2 weeks.

FIGURE 27-7 Chest lentigines (A) before, (B) 1 week after, and (C) 2 weeks after one photorejuvenation treatment with intense pulsed light.

(Copyright Rebecca Small, MD.)

Figure 27-8 shows the results of photorejuvenation treatments for lentigines and mottled pigmentation on the face of a 75-year-old patient (A) before and (B) after a series of five IPL treatments (Starlux, Palomar).

FIGURE 27-8 Lentigines (A) before and (B) after photorejuvenation treatments with intense pulsed light.

(Copyright Rebecca Small, MD.)

Figure 27-9 shows the results of photorejuvenation treatments for lentigines and mottled pigmentation on the face (A) before and (B) after a Q-switched 532 nm treatment (Laser Peel™, Medlite HOYA ConBio).

FIGURE 27-9 Lentigines and ephelides (A) before and (B) after photorejuvenation treatments with a Q-switched 532 nm laser.

(Courtesy of HOYA ConBio, Fremont, CA; B. Saal, MD, using laser.)

Figure 27-10 shows the results of photorejuvenation treatments for solar lentigines and under-eye pigmentation for a 48-year-old patient (A) before and (B) after two Q-switched 532 nm treatments (RevLite, HOYA ConBio).

FIGURE 27-10 Hyperpigmentaion (A) before and (B) after photorejuvenation treatments with a Q-switched 532 nm laser.

(Copyright Rebecca Small, MD.)

Figure 27-11 shows the results of photorejuvenation treatments for solar lentigines on the hands of a 55-year-old patient (A) before and (B) after five IPL treatments (Starlux, Palomar).

FIGURE 27-11 Hand lentigines (A) before and (B) after photorejuvenation treatments with intense pulsed light.

(Copyright Rebecca Small, MD.)

Figure 27-12 shows the results of photorejuvenation treatment for hyperpigmentation in a patient with Fitzpatrick VI skin type (A) before and (B) after Q-switched 1064 nm treatments (MedLite, HOYA ConBio).

FIGURE 27-12 Hyperpigmentation in a patient with darker Fitzpatrick skin type (A) before and (B) after photorejuvenation treatments with a Q-switched 1064 nm laser.

(Courtesy of HOYA ConBio, Fremont, CA; J. Garden, MD, using laser.)

Figure 27-13 shows the results of photorejuvenation treatment for melasma for a 41-year-old patient (A) before and (B) after Q-switched 1064 nm treatments (RevLite, HOYA ConBio).

FIGURE 27-13 Melasma (A) before and (B) after photorejuvenation treatments with a Q-switched 1064 nm laser

(Copyright Rebecca Small, MD.)

Figure 27-14 shows the results of photorejuvenation for nasal telangiectasias (A) before and (B) after 532 nm treatments (Gemini, Iridex).

FIGURE 27-14 Nose telangiectasias (A) before and (B) after photorejuvenation treatments with a 532 nm laser.

(Courtesy of Iridex, Mount View, CA; B. Berger, MD, using laser.)

Figure 27-15 shows the results of photorejuvenation treatments for rosacea for a 57-year-old (A) before and (B) after a series of five IPL treatments (Starlux, Palomar).

FIGURE 27-15 Rosacea (A) before and (B) after photorejuvenation treatments with intense pulsed light.

(Copyright Rebecca Small, MD.)

Aftercare

Mild swelling and redness are expected and usually resolve within a few hours to a few days after treatment. Application of a wrapped ice pack for 15 minutes every 1 to 2 hours and 1 to % hydrocortisone cream two times per day for 3 to 4 days or until redness resolves are recommended. Pigmented lesions typically continue to darken 1 to 2 days after treatment, forming microcrusts that flake off over 1 to 2 weeks, exposing lightened or resolved lesions. Vascular lesions that have turned grayish or darkened at the time of treatment usually fade over 1 to 2 weeks. Patients are instructed to contact their provider if erythema persists for more than 5 days because postinflammatory hyperpigmentation (PIH) can occur with prolonged erythema. Patients are also instructed to avoid intense, direct sun exposure and use a full-spectrum sunscreen (SPF 30 with zinc or titanium) daily for 4 weeks after treatment to help minimize the risk of undesired pigmentary changes.

Follow-Up

Photorejuvenation of benign epidermal pigmented lesions typically requires a series of three to five IPL treatments at monthly intervals for dramatic improvements. Lasers may require fewer treatments. Nonfacial areas are slower to exfoliate and heal, and usually require longer intervals between treatments, up to 8 weeks. One annual follow-up treatment is recommended for patients to maintain their results.

Photorejuvenation of benign vascular lesions also requires three to five IPL treatments at more frequent, bimonthly intervals, for optimal results. Again, lasers may require fewer treatments. Some vascular lesions, such as telangiectasias, can gradually recur over time, particularly in patients with rosacea, active lifestyles, or regular activities that cause flushing such as sauna and hot tub use. Annual or biannual follow-up treatments are recommended to maintain results. Discreet lesions such as cherry angiomas typically resolve without recurrence after one or two treatments.

Complications

Temporary redness and mild sunburn-like discomfort after treatment are common, which may last for a few hours to several days, and are not considered complications.

Pain is usually mild to moderate and only reported during treatment. Analgesic medications are not typically required.

Swelling may occur, particularly with aggressive treatment of the cheeks. Cold compresses are recommended as described above.

Rarely, urticaria may be seen. A daily oral antihistamine (e.g., cetirizine 10 mg) may be used until resolved, along with cold compresses and, once identified, these patients may be pretreated with an antihistamine 1 hour prior to procedures.

Purpura is due to localized rupture of superficial blood vessels and can occur when aggressive treatment parameters are used with superficial vessels. Utilizing longer pulse widths and lower fluences will usually avoid this complication. There is no specific treatment for this and purpuric lesions usually resolve in 1 to 2 weeks. Figure 27-16 shows an example of purpura immediately after an IPL photorejuvenation treatment on the cheek.

FIGURE 27-16 Purpura of the cheek immediately after a photorejuvenation treatment with IPL for rosacea.

(Copyright Rebecca Small, MD.)

Visible skin patterns or striping may be seen during the course of a series of treatments, particularly in patients with severely sun-damaged skin with background brown discoloration, called actinic bronzing. These patterns are usually the result of careful treatments with appropriate overlap of pulses, where the dark stripes represent the regions of overlap. Subsequent treatments usually blend skin patterns and striping; however, as with any pigmentary change, there is a small risk that these patterns may be permanent.

Pigmentary complications of hyperpigmentation and hypopigmentation are most commonly seen in darker Fitzpatrick skin types (IV)¹⁴ and in patients with a recent tan. These complications are more common with short pulse widths, high fluences, and poor epidermal cooling. Hyperpigmentation is usually transient (and rarely may be permanent), lasting in the order of months. The use of a lightening agent such as hydroquinone for 1 month prior to treatment and after treatment can reduce hyperpigmentation, particularly in darker skinned patients (see Chapter 24, Skin Care Products, for additional information). Hypopigmentation is a more significant complication. This may be temporary or permanent. Figure 27-17 shows stripes of hypopigmentation resulting from an overly aggressive IPL treatment for lentigines (not performed by the authors) on a patient with a darker skin type.

FIGURE 27-17 Hypopigmentation of the chest in a patient with darker Fitzpatrick skin type 6 weeks after IPL treatment (not performed by the author) for lentigines.

(Copyright Rebecca Small, MD.)

A burn may result from aggressive treatment parameters of short pulse widths and high fluences with inadequate epidermal cooling. Routine moist wound care is performed with application of an antibiotic ointment and bandage until healed. Tattoos and permanent makeup have concentrated ink pigments and treatment over these may result in full-thickness skin burns.

Postprocedure infections are rare with laser photorejuvenation treatments and require treatment specific to the infection. Infections such as herpes simplex and varicella zoster may be reactivated in the treatment area, and pretreatment prophylactic oral antiviral medication can reduce this risk (see the Procedure Preparation section above). Impetigo may occur, particularly with treatments around the mouth. Folliculitis may also occur, particularly after vigorous exercise, swimming or hot tub use immediately after treatments.

Scarring is very rare, but may occur with overaggressive treatments or with treatments complicated by infection.

Reduced hair growth in or adjacent to the treatment area may occur. This risk should be fully discussed if treating over men’s facial hair.

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 Technique

Providers may initially perform treatments on the face using conservative laser parameters with longer pulse widths and lower fluences in patients with light Fitzpatrick skin types (I through III). When getting started with IPL photorejuvenation treatment, conservative clinical endpoints for pigmentation are sought including darkening with minimal perilesional erythema, and for vascular lesions, sluggish refilling after compression.

Current Developments

Some of the new fractional laser technologies used for nonablative skin resurfacing show promise as photorejuventation treatments¹⁵ (see Chapter 29, Skin Resurfacing with Ablative Lasers). The fractionated 1550 nm wavelength has been shown to reduce red vascularities^16,17 and benign pigmented lesions^18,19 as well as improve skin texture²⁰ and scars (see Chapter 28, Wrinkle Reduction with Nonablative Lasers). Some newer devices combine chromophore-specific modalities with other modalities that are not chromophore specific to target pigmentation, vascularities, and skin texture, such as IPL with radio-frequency.²¹ Lasers with longer wavelengths, such as 940 nm, have been used for red vascular lesions and recently, a 980 nm wavelength laser²² has been used for targeting larger red facial vessels.

Photodynamic therapy (PDT) has also been used for photorejuvenation. PDT involves the use of a topical photosensitizing medication activated by light (usually LEDs or IPLs) . Commonly used photosensitizers include 5-aminolevulinic acid (ALA) and methyl ALA (mALA). ALA is selectively absorbed and concentrated in proliferating cells and pilosebaceous units where it is converted to protoporphyrin (PpIX). Upon activation with a light source, such as an IPL, laser (e.g., 585 nm), or LED, PpIX forms free radicals, which selectively destroy the target. PDT using ALA, activated by blue light, is currently FDA approved for treatment of nonhyperkeratotic actinic keratoses of the face and is also used off-label for photorejuvenation.²³ PDT has a greater cost to the patient than laser alone, more downtime with erythema and crusting, and requires strict patient avoidance of ambient sunlight post-treatment for 48 hours, because sun exposure can lead to extended ALA activation and associated complications.

Financial Considerations

Laser photorejuvenation is generally not reimbursable; however, some insurance companies may reimburse for treatment of rosacea. The charges for treatments vary and are largely determined by local prices. Individual treatment prices range from $350 to $600 for a single treatment to a large area such as the face or chest, and $150 to $300 for a small area such as the hands or neck. However, because photorejuvenation treatments are most effective with a series of treatments, packages of treatments (usually three or five) may be offered so that patients achieve the best possible results.

When covered by insurance, Box 27-2 lists the applicable ICD-9 codes for photorejuvenation procedures.

Conclusion

Photorejuvenation laser treatments effectively and safely reduce benign pigmented and vascular lesions associated with photoaging. Treatments have minimal discomfort, little to no recovery time, and high patient satisfaction and may be readily integrated into office-based aesthetic care.

Resources