salicylic acid is helpful in treatment of oily skin, textural changes, melasma, and post-inflammatory pigmentation with minimal side effects. Another benefit of salicylic acid is that it does not need to be neutralized. After applying salicylic acid to the skin, salt formation on the skin is seen.

16.6 Jessner’s Peel

Jessner’s solution is a combination of salicylic acid, lactic acid, and resorcinol in alcohol (Table 16.3) [11]. Considered a mild-medium peeling agent, this formulation was designed to minimize the toxicities inherent to each individual agent. This solution must be stored in a dark bottle as light will discolor the solution and cause staining. Repetitive layers of Jessner’s solution may be applied to affect a slightly deeper peel. Jessner’s solution peeling action is through intense keratolysis. Its ability to disrupt the barrier function of the epidermis makes it an ideal primer for TCA peels, allowing the TCA to penetrate effectively and evenly [11]. Independently, Jessner’s solution is an easy to use peeling agent without timing restriction. Skin sloughing occurs within 2–4 days after application with subsequent epidermal regrowth.

16.6.1 Medium Depth Peels

Medium-depth chemical peeling is defined as controlled damage to the papillary dermis, which can be performed in a single procedure [12]. Indications for medium-depth peel include destruction of epidermal lesions and actinic keratoses, resurfacing moderately photoaged skin, correction of dyschromias, and repair of mild acne scars. Although agents such as pyruvic acid or full-strength phenol can be used to achieve a medium depth peel, the classic agent is TCA.

Table 16.3 Jessner’s solution formula

16.7 Trichloroacetic Acid

TCA is a versatile chemo exfoliative agent, in that it can be used as a superficial intermediate-to-deep peeling agent in varying concentrations. The depth of penetration of a TCA peel corresponds to increasing concentrations of TCA. At lower concentrations of 10–35% TCA, only a superficial peel is rendered. The results of superficial depth TCA peels include mild reversal of fine wrinkles and improvement in dyspigmentation with less recovery period and risk than deeper TCA peels or peel combinations.

At higher concentrations, such as 50% and above, TCA behaves comparably to a phenol peel. However, the depth of the wound to the reticular dermis with 50+% TCA increases concurrently with the rate of scarring and dyschromias. Many authors feel that 35% is the highest concentration of TCA which can be reliably used. Therefore, to safely improve epidermal penetration to the desired medium-depth peel, 35% TCA is usually preceded by a superficial keratolytic agent such as solid CO2, Jessner’s solution, or 70% glycolic acid. Two proprietary TCA-based agents, the TCA Masque (ICN Pharmaceuticals, Costa Mesa, California) and the TCA Blue Peel (Obagi), are also commonly used.

TCAs peeling mechanism of action at lower concentrations is via protein precipitation. TCA is a keratocoagulant that produces a frosting or whitening of the skin, which is dependent on the concentration used. Level I frosting, which is defined as erythema with streaky whitening of the face, is the endpoint for superficial resurfacing. Level II frosting is described as even white-coated frosting with patches of erythema showing through. Level III frosting, clinically signifying penetration through the papillary dermis, is a solid white enamel frost with minimal visible erythema. Level III frosting should be reserved for regions exhibiting severe actinic damage.

The dosage of TCA applied is dependent on the amount of agent used, the concentration, and the physician’s technique. For example, vigorous rubbing of the agent, as compared with blotting, yields a deeper penetration. The systematic application of TCA with a sponge or brush involves treating the face in a sequence of subunits. During the procedure, if frosting is not uniform, reapplication may be performed until the desired level is reached. To achieve effective treatment of the whole face, certain areas and lesions require specialized care. Thicker keratotic areas may necessitate

additional or more vigorous application of the TCA for deeper penetration. Eyelid skin is treated with the patient’s head elevated and the eyes closed. The TCA is carefully applied with a semidry applicator extending to within 2–3 mm of the lid margin. With many variables involved, which can be specifically adjusted according the patient’s skin type and the areas being treated, the medium-depth TCA peel can be individualized for each patient.

Appropriate analgesia is necessary as TCA application is associated with an intense burning sensation that resolves within half an hour. Patient comfort may also be improved by cooling the face with a fan and by applying iced saline soaked sponges prior to moving from one facial region to another. Once the procedure is completed, skin sloughing proceeds for several days, and reepithelialization occurs within 7–10 days. Patient discomfort can be controlled with oral pain medications. An advantage of the TCA peels is that the solution is neutralized by the body’s serum, and there is no other associated toxicity.

16.8 Adjunctive Measures

In patients susceptible to hyperpigmentation, pretreatment with a bleaching agent may be preventive. Hydroquinone, an isomer of resorcinol and phenol, is commonly used. Other bleaching agents include kojic acid and azelaic acid.

Individuals with more significant laxity of deeper skin structures may benefit from other facial rejuvenative procedures including rhytidectomy, browlift, and/or blepharoplasty in appropriately selected patients. Simultaneous facelift and chemical peel are generally approached with caution as there is a higher likelihood of full-thickness flap loss when peeling over elevated flaps.

Other adjunctive cosmetic procedures include treatment of dynamic wrinkles with Botox and filling very deep furrows or scars with facial fillers.

16.9 Postoperative Care

Postoperative care is designed to provide an ideal environment for moist wound healing. Initially, a generous amount of bland ointment, such as Aquaphor, petroleum

jelly, or A&D ointment, is applied to the entire treatment area. This serves as an occlusive ointment, which protects and hydrates the skin. The use of more heavily formulated products can irritate the delicate, healing skin and interfere with the peeling process. Crisco vegetable shortening historically had been used quite successfully, but has since been reformulated and now may actually be irritating. Patients are instructed to reapply the ointment throughout the day or night, any time the face feels tight or dry. The initial inflammatory response is an erythematous and edematous reaction lasting from 12 to 36 h. During this period, patients may experience marked edema of the periocular region as well as the entire face. As the outer layers begin to shed, the patient is allowed to shower and gently wash the face with a mild cleanser. After showering, the face should be patted dry and a new coating of ointment applied.

Patients are instructed not to pick at the face during the recovery period. For best results, the patient should allow the skin to peel independently and resist the temptation to assist the peeling process. The use of loofahs, natural facial sponges, skin brushes, or any skin exfoliants is forbidden as manipulation of the skin prior to complete reepithelialization can result in prolonged erythema, bacterial infection, and scarring. Cool clean compresses and elevation of the head of bed can provide symptomatic relief of discomfort. The skin is generally reepithelialized by 7–10 days postpeel, at which point makeup can be applied. A formal consultation with an esthetician is valuable in educating patients on how to camouflage resolving erythema. Skin care services such as superficial peels and micro dermabrasion are not to be resumed until 3 months after a medium-deep peel. Medium-depth chemical peels need not be repeated for at least 1 year. Sunscreen is crucial to prevent further actinic damage and to prevent hyperpigmentation. The patients should be meticulous in avoiding sun exposure during this period, as any sun damage during this delicate recovery time could prolong post-procedure erythema and the wound healing process.

Following chemical peeling, some practitioners prescribe topical agents containing platelet products or growth factors. Although these products have been reported to improve wound healing, no randomized controlled clinical trials presently support their use in this specific setting. Further research is necessary to determine the clinical utility of these agents in the chemical peel process.

16.10 Complications

Chemical peeling may result in a profound rejuvenation of facial skin; however, this treatment is not without potential complications. Results and complications are generally related to the depth of wounding, with deeper penetration peels providing more marked results and a concomitant higher incidence of complications.

When the resurfacing agent removes the epidermis and a portion of the dermis, an important immunologic barrier between the patient and the environment no longer exists. An occlusive dressing, a topical ointment, or the body’s own exudate provides some protection; however, the healing wound is more susceptible to both bacterial and fungal infections than the undisturbed skin. Delayed healing can be seen secondary to viral, bacterial, and fungal infections. Although bacterial infections are relatively rare, these infections can be avoided with the use of perioperative antiviral and antibiotic medications and good wound care. Infectious complications demand vigilance and aggressive therapy with oral and topical antibiotics. Staphylococcus and Streptococcus are the most common culprits when bacterial infections occur. Pseudomonas infections occasionally occur and may be recognized by Wood’s lamp examination. Treatment of pseudomonas infections includes cleansing with 0.25% acetic acid and appropriate antibiotics. The trauma of the resurfacing procedure may reactivate a viral infection (e.g., herpes simplex). Persistent pain after the peel may be an indication of secondary herpetic infection. Preoperative prophylaxis for HSV is prudent as herpes infections have been documented in patients with no prior history of outbreaks. Herpes exacerbations are treated with oral and topical antivirals until resolution. The physician must be vigilant for signs of infection to prevent scarring.

Cicatricial complications may be cosmetic failures alone or they may complicate a case by imposing a functional deficit on a patient, particularly in the periorbital area. Scarring is one of the most significant complications following chemical peel. Care must be taken to properly screen patients. The use of Accutane in the last year or two, history of keloid formation, radiation therapy, and collagen vascular disease all may predispose to scarring and may make the patient a poor candidate for chemical peel. Scarring is unusual when the chemical agent is properly mixed and when

the skin is effectively cleansed of all surface debris. Nevertheless, scarring may occur if multiple passes of the peeling agent are applied to a single area during the same session. An initial pass weakens the barrier and can permit a subsequent pass of the chemical to penetrate to a deeper level in the skin. Patiently waiting for frosting to occur can prevent this technical error. Delay in wound healing may lead to scarring, a severe complication requiring close follow-up and aggressive early treatment. Topical or intralesional steroids, silicone sheeting, pressure dressing, and scar massage may improve outcome. Scar excision or dermabrasion may be necessary in cases of persistent unsatisfactory results.

Pigment changes after resurfacing are the most frustrating to the surgeon and the patient because they can occur despite proper patient selection and excellent technique. They are also among the most common complications. Pigment complications after chemical peels may involve either hyperor hypopigmentary changes. Erythema generally subsides within 90 days, but may persist as hyperpigmentation. Patients at increased risk are those taking oral contraceptive pills, exogenous estrogens, or other photosensitizing medications or patients with a history of posttraumatic hyperpigmentation. Hyperpigmentation after a chemical peel is best avoided by careful patient selection. Test spots may be performed on darkerskinned patients before the peel. The application of topical hydrocortisone or a short course of systemic steroids may lead to earlier resolution. Other treatments including transretinoic acid, glycolic acid, or hydroquinone can be useful in reducing pigmentary changes after the peel. Accompanying pruritus may be treated with oral antihistamines. Following chemical peeling, the skin is typically hypersensitive to the sun, which may be a source of additional hyperpigmentation. Sun avoidance and daily sunscreen application following the peel should be strongly endorsed to minimize pigmentary alterations. Preand posttreatment with a bleaching agent, such as hydroquinone, may minimize this problem in the susceptible patient.

Hypopigmentation is a late sequela of resurfacing and is extremely difficult to treat. Hypopigmentation is the result of melanocyte destruction or inhibition. Melanocytes are not capable of regeneration or division. It is encountered most frequently following phenol peeling, which has caused many clinicians to

abandon phenol in favor of other peeling agents. Most noticeable in darker skinned patients, hypopigmentation may be difficult to assess until post-pro- cedure erythema has subsided, at which point the condition may have unfortunately become permanent. Care must be taken upon initial application of the peel agent to feather the margins to avoid a sharp border between the treated and untreated areas. This may be accomplished either by using a less concentrated formulation or by applying less of the peeling agent in these regions. Camouflage makeup may conceal this and other pigmentary disturbances. When a line of demarcation is apparent between peeled and unpeeled areas of the face, the untreated skin may be resurfaced. Feathering a chemical peel into the neck can help blur the demarcation between the jaw and the neck.

Milia commonly develop after a chemical peel. Their appearance 2–3 weeks after a peel may be secondary to the use of occlusive ointments used during the healing period. They may spontaneously resolve or require removal by mild exfoliation or lancing.

Although uncommon, marked conjunctivitis and corneal abrasions have been reported after seepage of 35% TCA into the eye of a patient undergoing peel application. Chemical peel solutions must be applied extremely carefully in the periorbital regions to avoid ocular complications, which can be quite grave if not addressed in a timely manner [13].

Systemic complications from chemical peels resurfacing are quite uncommon, yet potentially disastrous. Toxic shock syndrome (secondary to Staphylococcus aureus infection), has been rarely reported, and can occur in association with any infected wound. Most often, toxic shock syndrome begins on the second or third day after treatment often presenting with fever,

a desquamating rash, and hypotension. Treatment includes hospital admission, supportive care, aggressive cleansing of the wound, and antibiotics.

16.11 Discussion

The art of facial chemical peels encompasses a wide variety of chemical agents and application techniques. When a standardized technique is used, it is possible to quantify the therapeutic effects and to predict the outcome reliably. Variations of chemical peels will be used as clinicians try to achieve better results. If possible, variations from standard techniques should be scientifically studied and quantified to establish their safety and efficacy. Using careful clinical assessment and technique, one can safely and reliably undertake facial chemical peeling to combat photoaging.

16.12 Conclusions

Expertly performed chemical peels with healthy wound healing can achieve a significant reduction in facial rhytids, dyschromias, solar changes, acne, and superficial scarring. The best results for a chemical peel rests both with the cosmetic surgeon as well as the patient. The need for explicit pretreatment education and stringent posttreatment care cannot be overemphasized. Ultimately it is a combination of the surgeon’s technique and the patient’s compliance with the wound care instructions that determines the overall result. Setting realistic expectations for patients is imperative to the success of the chemical peeling process and will serve to maximize patient satisfaction (Figs. 16.1–16.3).

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Fig. 16.2 Forty-nine- year-old female. (a, b) Prior to treatment. (c, d) After 35% medium-depth peel

B.A. Bassichis