TCA peels

Monheit GD (1989) Jessner s + TCA peel a medium depth chemical peel. J Dermatol Surg Oncol 15 ... 

Epidermal growths such as actinic keratosis, lentigines or thin seborrheic keratoses can all be treated effectively with 25-35% TCA peels. Thicker epidermal growths or growths involving the dermis will be more resistant to treatment such as hypertrophic actinic keratoses and thicker seborrheic keratoses and may even be resistant to a medium-depth peel. Resistant lesions many times are best treated with a combination of a medium-depth chemical peel and other modalities such as manual dermasanding or CO, laser. 

If a Jessner s-35% TCA peel (Monheit) is performed, Jessner s solution is applied first prior to the TCA in an even sequential fashion from the forehead to the rest of the face, waiting 2 to 3 min to allow for penetration and assessment of frost. Typically this will produce a level 1 frost, erythema with faint reticulate whitening... 

Trichloroacetic Acid (TCA) causes precipitation of proteins and coagulative necrosis of epidermal cells [4]. The extent of damage is indeed concentration dependent. Concentrations range from 10 to 50%. Superficial TCA peeling is induced by concentrations of 10-30% whereas higher concentrations cause medium depth or deep peeling. The combination of salicylic acid followed by TCA 10-15% induces superficial wounding. 

Ethanol formulations of salicylic acid (20 and 30%) are used for combination peeling (see salicylic acid section). Trichloroacetic acid is prepared as an aqueous solution, since ethanol solutions do not penetrate the skin. It is prepared by mixing the appropriate concentration of crystals with up to 100 cc of distilled water. Ten and fifteen percent TCA is prepared by mixing 10 or 15 g of crystals in up to 100 cc of total volume, respectively. Aqueous solutions of TCA remain stable for up to 6 months unless contaminated. Other methods have been used to formulate TCA peeling solutions however, the weight/volume methods appear to be the most reliable formulation [5]. Premixed TCA solutions are available from a variety of medical... 

Fig. 10.1. a African American male with severe post-inflammatory hyperpigmentation, b Note significant improvement after combination salicylic acid/TCA peeling... 

The combination of salicylic acid and TCA 15% is also an effective treatment for mild to moderate photodamage, acne and melasma in types 1-111. Moderate to excellent improvement has been observed (Figs. 10.3a, b, 10.4a, b and 10.5a, b). Hence, the combination salicylic acid/TCA peeling protocol can be used in all skin types. 

There are few contraindications to combination salicylic acid/TCA peeling. The combination regimen is tolerated in all skin types and all ra-cial/ethnic groups. General contraindications include salicylate hypersensitivity unrealistic patient expectations active inflammation/der-... 

Fig. 10.2. a Patient with recalcitrant melasma unresponsive to glycolic acid or salicylic acid peels, b Responded to combination salicylic acid/TCA peeling... 

Fig. 10.5. a Patient with facial melasma, b Note improvement after combination salicylic acid/TCA peel... 

The advantages of combination salicylic acid/ TCA peeling include ... 

Fig. ii.2oa-c. Improvement of papulo-pustular acne (a) after 3 sessions pf 25% TCA peeling (b, c). This patient has been treated with oral isotretinoin 6 months before peeling procedure. 

Fig. 12.5a, b. Actinic keratosis treated with cryotherapy and 25% TCA peeling... 

Fig. i3.2b-d. Hematoxylin/eosin stains of biopsies of c Twenty-five percent TCA induced mid-epidermal back skin taken 24 b post-chemical peeling, b Salicylic wounding/separation. d Thirty percent TCA peel caused acid 30%. Note mild lymphohistiocytic infiltrate, deep epidermal separation... 

TCA peels were first described by Roberts in 1926. Many consider TCA the gold standard by which other peels are measured. Concentrations of 10-30% are used for superficial peeling. TCA precipitates epidermal proteins, causing sloughing and necrosis of the treated area. The extent of damage is concentration dependent. In contrast to glycolic acid, Jessner s solu-... 

In a histometric, immunohistochemical and ultrastructural study, TCA peeling in concentrations of 10,20 and 30% were compared with dermabrasion in nine dark-skinned patients (Fitzpatrick s IV and V) with photodamage [24]. Both procedures induced increasing amounts of types I and III collagen. However,... 

Fig. 13.5a, b. Moderate improvement in melasma after a series of two 15% TCA peels plus hydroquinone 6%... 

There is minimal published data on the use of combination peeling protocols in deeply pigmented skin (Fitzpatrick skin types IV-Vl). The author has reported the efficacy of combination peeling with salicylic acid 20 and 30% in combination with 10% TCA for recalcitrant melasma patients. This peeling regimen was well tolerated with minimal side effects in darker racial ethnic groups (see Salicylic acid/TCA peel section). 

Fig. 13.6. Post-peel persistent hypopigmentation following a 35% TCA peel...

Trichloroacetic acid and phenol peels (see peel sections) have been used extensively to treat photodamage [60, 61]. However, TCA peels in concentrations above 35% are unpredictable. Albeit efficacious for severe photodamage, phenol peels are associated with myriad side effects [61]. Hence, combination medium-depth peeling agents have become increasingly popu-... 

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