Intense Pulsed Light for Full Facial Rejuvenation

Nonablative broadband light and laser devices have grown in popularity in recent years. One such device, the intense pulsed light (IPL), was introduced in the mid-1990s and has become a well-recognized treatment modality to improve the appearance of the photoaged face. Photoaging consists of the characteristic clinical changes to facial and other sun-exposed skin caused by chronic exposure to ultraviolet (UV) light. These changes include the appearance of telangectasias, rough texture, fine and coarse wrinkles, yellow or sallow color, and mottled pigmentation.1

The overall appearance of aging skin is primarily related to the quantitative effects of sun exposure over time. UV radiation damages structural components of the dermis, chiefly collagen and elastic fibers. A common pathway whereby photoaging occurs is through UV-generated reactive oxygen species.2 Facial appearance, however, is also affected by genetic factors, intrinsic factors, disease processes such as rosacea, and the overall loss of cutaneous elasticity associated with age. Signs of photoaging are becoming more evident in increasingly younger individuals, especially those regularly engaged in outdoor professions or recreational activities, as a consequence of exposure to increasingly high levels of UV radiation.3 Treatment of these changes with nonablative devices has been termed photorejuvenation and can be approached in a rational, stepwise fashion (Table 2–1).

Nonablative laser devices classically emit energy in coherent wavelengths within the near infrared to infrared spectrum (Table 2–2). Intradermal water is the target chromophore and heat generated by this interaction causes thermal injury within the dermis, initiating a cascade of molecular repair events that promote collagen formation and deposition.4 Clinically, this is

manifested by subtle improvements in fine wrinkling and skin texture.

Alternatively, vascular-specific laser devices with wavelengths from 585 to 600 nm are also thought to cause thermal injury to dermal elements. These lasers are commonly used to treat the telangiectatic component. Energy is selectively absorbed by the target chromophore, hemoglobin. Light energy is converted to heat, which damages the vessel walls and radiates into the surrounding dermis, causing injury and repair with the formation of new collagen.5

By contrast, IPL is one proprietary noncoherent device in a class of several such devices, which emits a spectrum of wavelengths in the 515 to 1200 nm range. It allows for variation of pulse length/mode, delay between pulses, and fluence energy. Cutoff filters eliminate the lower range of wavelength of light emitted. Consequently, patients of darker skin types (Fitzpatrick III–IV) can be safely treated. Target lesions include blood vessels as well as lentigines. Selective thermal heating of chromophores including hemoglobin, water-containing tissue (collagen), and melanin is thought to induce neocollagenesis.6 Intrinsic cooling provided by IPL devices allows for repair of photoaging structural changes in the skin without disruption of cutaneous integrity. The resulting patient treatment has a low-risk profile and minimal downtime.

Technology

IPL devices consist of a flashlamp housed in an optical treatment head, in which reflecting mirrors are water cooled (Fig. 2–1). Optically coated quartz filters are placed over the window of the optical treatment head

Table 2–1 Problem-Oriented Nonablative Treatment Algorithm for Facial Lesions

IPL, intense pulsed light; PDL, Pulsed dye laser (595 nm); CT2, CoolTouch II Laser (1320 nm)(Cool Touch Corp., Roseville, California).

to eliminate wavelengths lower than the filter. For faster recycling times, certain optical heads have water circulating around the flashlamp. The filter crystals must be optically coupled to the skin with a waterbased gel.3

When filtered, the IPL device is capable of emitting a broad bandwidth of light from 515 to 1200 nm. This bandwidth is modified by the application of filters, which exclude wavelengths lower than the filter to help protect against epidermal heating. Although the output is not uniform across this spectrum, it has been shown that during a 10 msec pulse relatively high doses of yellow light at 600 nm are emitted, with far less red and infrared, although output clearly is demonstrated beyond 1000 nm.3

Filters applied for vascular lesions are 515, 550, 570, and 590 nm. Longer filters 615, 645, 695, and 755 nm, which cut off much more of the yellow wavelengths, are used for various applications but most commonly for photoepilation. Importantly, IPL involves not only

Figure 2–1 The head of the Lumenis Quantum intense pulsed light device (Lumenis Corp., Yokneam, Israel).

Table 2–2 Select Nonablative Devices, Including Coherent and Noncoherent Devices and Vascular Lasers

Syneron Aurora

Palomar Starlux

filtering and eliminating the lowest wavelengths emitted by the flashlamp but also the ability to easily manipulate pulse durations and to couple these pulse durations with precise resting or thermal relaxation times.

Indications

Elements of IPL photorejuvenation treatment for the photoaged face include (1) identification of characteristic skin changes, both individual lesions and the photoaging complex; (2) identification of subpurpuric, subablative parameters; and (3) maintenance programs.7,8

One of the most frequently requested facial cosmetic procedures is elimination of facial telangiectasias. Removal of telangiectasias on the nose and cheeks results in a clinically smoother appearance to the skin texture.9 To treat blood vessels by light energy, selective photothermolysis must be achieved. The filtered flashlamp noncoherent IPL source meets the requirements for selective photothermolysis by virtue of the absorption coefficient of blood in the vessel being higher than that of the bloodless dermis for a very broad range of wavelengths.9

Facial telangiectasias have been found to be generally more responsive to IPL treatment than leg telangiectasias. This is thought to be due to several factors: thinner overlying epidermis, thinner vessel walls rendering the endothelium more susceptible to thermal damage, higher relative amounts of oxyhemoglobin (better chromophore than deoxygenated hemoglobin), and lower hydrostatic pressures. As a result, the response of facial telangiectasias is more predictable with

Figure 2–2 Successful treatment of cheek telangiectasias. (A) Prior to treatment. (B) After three treatments, spaced approximately 4 weeks apart.

an approximate 95% resolution rate after three treatments (Figs. 2–2A,B).8

General parameters for the IPL treatment of facial telangiectasias includes a double pulse of 2.4 to 4.0 msec duration with a 560, 570, or 590 nm filter, depending on the degree of red coloration of the vessels. For example, a 590 nm filter would be used for less blue, brighter red (oxyhemoglobin-rich) vessels. Delay times between the pulses vary depending on the skin coloration. Darker

skin types, such as Asian skin, require longer delays or 20 to 40 msec between pulses so that the heat generated within the vessel can be conducted safely to the surrounding tissues without potential damage to the epidermis. Delay times in the range of 10 to 20 msec are more common for lighter skin types.9 Fluences typically between 20 and 30 J/cm2 are used to start. If a pulse duration of 4 msec is used, then larger fluence of between 40 to 45 J/cm2 can be used.9

The use of ice-cold coupling gel in conjunction with the chilled crystal tip of the IPL device is paramount to achieving optimal results with all IPL treatments, while helping to minimize the risk of epidermal damage, which results in blistering and burning. The ice-cold gel’s purpose is twofold: (1) it serves as a focusing medium between the light emitted from the device to the air to the skin and (2) it serves as a heat sink to absorb heat that gets absorbed by or radiated to the epidermis from the target chromophores in the epidermis and dermis.

Clinical observation of subtle changes in vessel quality after treatment is paramount to achieving highquality, reproducible results. Within seconds to minutes after a treatment, vessels should darken to a reddishblue color (Fig. 2–3A,B). This coloration can travel slightly beyond the treated area as the heat energy conducts along the vessel. Often, a mild “vessel blurring” or local urticaria-like reaction will be observed around the vessel. This reaction may take several minutes to manifest, and it is often necessary to wipe away coupling gel for better visualization. Using this approach, excellent results can be achieved (Fig. 2–4A,B). Risk of adverse effects is greatly minimized by observation of several test pulses at different fluences prior to treating the entire affected area. The incidence of purpura is very low in this setting, and lower than that observed with classic pulsed-dye lasers. Patients should be told in advance to expect lesion clearance in one to three treatments. Perinasal telangiectasias often take multiple treatments, a presumed consequence of their relatively high-pressure, high-flow state secondary to their branching proximity to the angular artery.

Figure 2–3 Note the subtle darkening of the left nasal alar vessels. (A) Before treatment. (B) Immediately following a pulse with an intense pulsed light device.

Solar lentigines, known to patients as sun spots and liver spots, are another characteristic lesion observed on the photoaged face. These classically present as gradually appearing, well-defined light and dark brown round

Figure 2–5 A marked reduction in lentigines. (A) Prior to treatment. (B) Four weeks after a single treatment.

Figure 2–4 Successful treatment of left cheek telangiectasias. (A) Prior to treatment. (B) Six weeks after a single treatment.

macules and patches on the malar cheeks and forehead. Often mistaken for moles by patients, these lesions are very effectively treated with IPL devices (Fig. 2–5A,B). Suggested parameters for treatment are fluences of 24 to 33 J/cm2, using a 560 or 590 nm cutoff filter with a 4 msec double pulse with 20 to 40 msec delays.10 Treatment results in an immediate darkening of the lesion, a

Table 2–3 General Guidelines for Intense Pulsed Light Treatment

Initial Treatment

Elicit history of any recent tanning (natural or self-tanning products)

Start conservatively with lower fluences, 22–25 J/cm2

Examine results of a test spot (laterally or inconspicuously placed) and adjust parameters according to immediate clinical response

Endpoint of therapy is mild edema and moderate erythema, vessel darkening/blurring, and lentigines darkening

Subsequent Treatments

From previous treatment, note history of purpura, swelling, or blister formation

Grade improvement in the following: skin texture, pigmentation, redness/flushing, pore prominence

Purpura, prolonged erythema, or crusting is abnormal and necessitates lowering the dose settings; darkening or crusting of lentigenes lasting 7–10 days, erythema lasting 2–3 days, and mild edema lasting 1 day are considered to be normal responses

If patient reports no complications, increase energy by 0.5 to 2.0 J/cm2 per treatment; after initial two to three treatments at 4-week intervals, can do maintenance treatments at 6-month intervals for photoaging; stress importance of sunscreen

Adapted from Sadick NS, Weiss R. Intense pulsed-light photorejuvenation. Semin Cutan Med Surg 2002;21:280–288

reaction that should be thoroughly explained to patients prior to treatment. As with telangiectasias, it may be necessary to pause treatment to view this endpoint after a series of test pulses before continuing treatment. Within 24 to 48 hours posttreatment, lentigines will take on a darker and crusty appearance. These remnants will spontaneously peel away over a 5- to 6-day posttreatment period (Fig. 2–6A–C), or they can be removed by using microdermabrasion.

Conclusion

Photorejuvenation has been described as a dynamic nonablative process involving the use of IPL in a low-fluence, nonablative manner to reduce mottled pigmentation and telangiectasias and smooth the textural surface of the skin11 (Table 2–3). Other than mild transient erythema, there are no other immediate visible signs of treatment, and patients may resume normal activities immediately.

References

1.Kligman AM. Early destructive effect of sunlight on human skin. JAMA 1969;210:2377–2380

2.Kang S, Fisher GJ, Voorhees JJ. Photoaging: pathogenesis, prevention, and treatment. Clin Geriatr Med 2001;17:643–659

3.Weiss RA, Weiss MA. Noncoherent light sources. In Kauvar ANB, Hruza G, eds. Principles and Practices in Cutaneous Laser Surgery. New York: Marcel Dekker.

4.Goldberg DJ. New collagen formation after dermal remodeling with an intense pulsed light source. J Cutan Laser Ther 2000;2:59–61

5.Moody BR, McCarthy JE, Hruza GJ. Collagen remodeling after 585-nm pulsed dye laser irradiation: an ultrasonographic analysis. Dermatol Surg 2003;29:997–999

6.Nelson JS, Majaron B, Kelly KM. What is nonablative photorejuvenation of human skin? Semin Cutan Med Surg 2002; 21:238–250

7.Weiss RA, Weiss MA, Beasley KL. Rejuvenation of photoaged skin: 5 years results with intense pulsed light of the face, neck, and chest. Dermatol Surg 2002;28:1115–1119

8.Sadick NS, Weiss R. Intense pulsed-light photorejuvenation. Semin Cutan Med Surg 2002;21:280–287

9.Goldman MP. Intense pulsed light and nonablative approaches to photoaging. In Rigel DS, Weiss RA, Lim HW, et al, eds. Photoaging. New York: Marcel Dekker; 2004:165–183.

10.Huang YL, Liao YL, Lee SH, Hong HS. Intense pulsed light for the treatment of facial freckles in Asian skin. Dermatol Surg 2002;28:1007–1012

11.Bitter PH. Noninvasive rejuvenation of photodamaged skin using serial, full-face intense pulsed light treatments. Dermatol Surg 2000;26:835–842