As medical advancements have increased not only our life span but also our quality of life, it is natural to expect a greater public desire to undo the untoward effects of sunlight, age, and genetics. This has created a myriad of unsubstantiated skin care products, and practitioners of wonder technologies promising unrealistic end results. Chemical peeling has withstood both the harshest critics of safety and of results. Starting with lay peelers in the early 20th century, chemexfoliation has provided not only a stalwart treatment for practitioners of skin rejuvenation but also the standard by which other modalities are judged. Various chemical formulations have provided treatment for rhytids, lentigos, dyschromias, and actinic damage. The goal of this chapter is to address some more recent changes in chemical peel techniques; to uproot some old, outdated tenets; and to discuss the versatility of Hetter chemical peels.
The history of chemical peeling did not begin in the hands of physicians but rather in those of the lay peelers. In the 1920s, Hollywood was the fertile ground for these early practitioners as the stars of early motion pictures wished to maintain both a youthful appearance and career longevity. It was not until the 1950s and 1960s when physicians wished not only to learn these practices but also to wrestle them away from prominent lay peelers trained by Jean DeDesly and Antoinette LaGasse. Gregory Hetter, in his four-part series in 2000, eloquently describes a detailed history of the passing of the chemical peeling art from the lay peelers to the plastic surgeons of the 1950s and 1960s.
As chemical peeling transformed to the realm of medical science, much literature was produced regarding the experiences of plastic surgeons. Not all experiences were matched with scientific scrutiny. Instead, in some cases, dogma was written and adhered to for decades. Much of this dogma was born out of the use of the Baker-Gordon phenol-croton oil formulation (Table 193.1
), the earliest formula widely used by physician peelers.
Defining an individual patient’s suitability for chemical peeling is paramount for the cosmetic surgeon. Not only does the patient need to be physically suitable for the peel but also the patient needs to have appropriate expectations of what the peel can accomplish. Rhytids and photodamage must be distinguished from age-related gravitational changes, jowling, and facial fat volume loss.
The ideal chemical peel patient is one with fair skin, blue eyes, and mild, shallow rhytids. However, this only represents a minority of the patients who will present seeking treatment for rhytids and photodamage. In order to help define the patient’s skin type, the Fitzpatrick scale (Table 193.2
) is most often employed. Patients can also be rated by their skin type, complexion, skin texture, thickness, and photoaging. A useful categorizing scheme is the one described by Glogau (Table 193.3
The patient’s medical history and lifestyle must be thoroughly discussed prior to the planning stages of the peel. Relative contraindications for any resurfacing procedure include cutaneous radiation history, smoking, active or frequent herpes simplex virus (HSV) infections, diabetes mellitus, or a history of hypertrophic scar formation or keloids. Birth control pills, exogenous estrogens (including soaps and cosmetics containing lavender oil), or photosensitizing drugs are to be avoided due to risks of hyperpigmentation. Due to elevated estrogen levels of pregnancy, the patient should not have plans to become pregnant within the first 6 months after the chemical peel (1
Lifestyle and habitual activities, more specifically, sun exposure and smoking, should be addressed. Due to the
microvascular damage that ensues from nicotine, a chemical peel in the face of chronic smoking can lead to poor tissue healing and poor cosmetic results. Practitioners should be honest and frank regarding the risks of smoking, and a cessation program should be recommended. Smokers should stop smoking 1 month prior to a chemical peel and should avoid smoking for at least 6 months after the peel. Ultraviolet light (UV) exposure can be equally problematic in the postoperative period. A patient’s habitual sun exposure should be assessed prior to proceeding with the peel. The patient should be advised that chronic or frequent sun exposure should be avoided after the chemical peel. If this is unacceptable to the patient, the practitioner should consider other options and not perform a peel.
TABLE 193.1 THE “CLASSIC” BAKER AND BAKER-GORDON FORMULATIONS
Original Baker Formulation
Phenol USP 88%
Croton oil (27 guttas = 1 mL)
Isotretinoin (Accutane) use is an absolute contraindication to chemical peeling or any other resurfacing procedure. Postpeel reepithelialization relies upon the epidermis within hair follicles and sebaceous glands. Isotretinoin prevents reepithelialization from these locations. Most recommendations include a cessation period of oral isotretinoin for 12 to 24 months prior to the peel.
The patient’s expectations should be clarified and agreed upon with the practitioner. The patient’s axillary skin can often well represent the final product of a chemical peel, as long as that area has not had excessive UV light exposure over the patient’s lifetime (2
TABLE 193.2 FITZPATRICK CLASSIFICATION SCALE
White; very fair; red or blond hair; blue eyes; freckles
Always burns, never tans
White; fair; red or blond hair; blue; hazel or green eyes
Usually burns, tans with difficulty
Cream white; fair with any eye or hair color; very common
Sometimes mild burn, gradually tans
Brown; typical Mediterranean Caucasian skin
Rarely burns, tans with ease
Dark brown; mid-eastern skin types
Very rarely burns, tans very easily
Never burns, tans very easily
Proper skin preparation is essential and contributes to optimizing results and minimizing complications. Preoperatively, the use of sunscreens which block UVA and UVB irradiation will decrease melanocyte activity and prevent skin tanning and sunburns. Sunscreen usage should begin 3 months prior to the peel in combination with minimal sun exposure.
Topical tretinoin (Retin-A) is recommended for 6 to 12 weeks prior to the peel. Animal studies have demonstrated clinical and histologic healing benefits of tretinoin prior to dermabrasion. Synergistic qualities of pretreatment topical tretinoin and trichloroacetic acid (TCA) peels have been shown to sustain the effects of the chemical peel (3
). Tretinoin aids in reepithelialization (5
) and leads to increased melanin distribution. After tretinoin treatment, the thickened epidermis displays decreased corneocyte adhesion, decreased stratum corneum thickness, and neocollagen production, all of which are beneficial to the peel and the postoperative result. This thickened and uniform epidermis aids in the uniform application of the peeling agent (6
The patient should begin nightly treatments with topical tretinoin 6 weeks prior to the peel, and these should be continued after the postpeel reepithelialization is
completed. The dose range recommended is between 0.025% and 0.1%. However, there is no literature describing an improved benefit with the higher dosing, suggesting that lower concentrations may be just as effective. Concentration of tretinoin becomes important in those patients who are sensitive to its use. The patient should be warned of the potential side effects including irritation, erythema, and flaking of the skin. When these complications are observed, the dose should be decreased or its use should be discontinued altogether.
TABLE 193.3 GLOGAU CLASSIFICATION SCALE
Patient age: 20s-30s
Mild pigment changes
No “age spots”
“Wrinkles in Motion”
Patient age: 30s-40s
Early to moderate photoaging
Appearance of smile lines
Early brown “age spots”
Skin pores more prominent
Early changes in skin texture
“Wrinkles at Rest”
Patient age: 50s and older
Prominent brown pigmentation
Visible brown “age spots”
Prominent, small blood vessels
Wrinkles, even at rest
Patient age: 60s or 70s
Yellow-gray skin color
Prior skin cancers
Precancerous skin changes (actinic keratosis)
Also beneficial in the pretreatment of all peel patients, hydroquinone is most effective in those patients with lentigos, dyschromias, and Fitzpatrick type III, IV, V, and VI skin types, due to the higher risk of postpeel postinflammatory hyperpigmentation (PIH). Hydroquinone blocks the conversion of tyrosine to L-dopa by tyrosinase, thus decreasing melanin production. Hydroquinone, in a concentration of 4% to 8%, should be started 4 to 6 weeks prior to resurfacing. Like tretinoin, hydroquinone should be started after the peel as soon as the patient’s skin can tolerate its application.
Even if patients have no recollection of prior herpetic vesicle occurrence, all patients should be warned of the possibility of HSV outbreaks. Patients can have a latent infection even in the setting of a negative history. Common and advisable practice is to start any patient with a negative history on a prophylactic dose of antiviral medication, such as acyclovir 400 mg three times a day, 3 days prior to and continued for at least 7 days after the peel. For those patients with a positive history of active HSV infections, a therapeutic dose of antiviral medication should be employed, such as valacyclovir 1 g three times a day for the aforementioned time period. Postpeel herpetic infections can be unnerving for the practitioner but are devastating for the patient. Therefore, all precautions should be taken to avoid them.
In order to maintain appropriate and uniform depth of penetration of the peeling agent, avoidance of waxing, dermabrasion, and electrolysis should be strictly maintained for 3 to 4 weeks prior to peeling.