Chemical peel 1

• 'Chemoexfoliation, also known as chemical peeling, is a method of targeted cutaneous ablation using specific caustic agents that allow for rapid, predictable, and uniform thickness of chemoablation to a desired cutaneous depth, ultimately resulting in an improved appearance of skin.'

  
• Indications of chemical peeling

  • Pigmentary disorders
  • Inflammatory disorders
  • Scarring
  • Chronoaging
  • Pre-cancerous lesions

  
• Pigmentary disorders

  • Lentigines
  • Ephelides
  • Melasma
• Inflammatory disorders

  • Acne
  • Rosacea
• Scarring

  • Acne scarring
  • Traumatic scarring
  • Surgical scarring
• Chronoaging

  • Superficial and medium-depth rhytides
• Pre-cancerous lesions

  • Actinic keratoses
• Superficial peels

  Penetrate only the epidermis
• Medium-depth peels

  Affect the entire epidermis and a portion of the papillary dermis

  
• Deep peels

  Aim to penetrate to the level of the midreticular dermis
• Superficial peels

  • Result in controlled keratocoagulation and liquefaction of the cells confined to the epidermis
  • Goal is to treat conditions confined to the epidermis, while minimizing recovery downtime and risk of side effects

  
• Superficial peels

  • Low-to-medium strength alpha-hydroxy acids (AHA) (e.g., 30–50% glycolic and 10–30% lactic acid)
  • 40% mandelic acid
  • Low concentrations or monolayer applications of beta-hydroxy salicylic acid (30%) or alpha-keto pyruvic acid (50%)
• Keratocoagulation (frosting)

  Protein denaturation of keratin and collagen that results in a "white frost" on the skin where the chemical agent has been applied
• Levels of frosting

  • Level I: Erythema with a stringy or patchy light frosting
  • Level II: Uniform, white-coated frosting with underlying erythema showing through
  • Level III: Solid white enamel frosting with little to no background erythema
• Commonly used superficial peels

  • AHAs (e.g. glycolic acid, lactic acid, mandelic acid)
  • BHAs (e.g. salicylic acid)
  • AKAs (e.g. pyruvic acid)
• Glycolic acid

  The most popular and time-tested superficial peeling agent, derived from sugar cane, smallest and simplest AHA, highly hydrophilic
• When properly used, superficial exfoliation with glycolic acid at concentrations of 30 to 50% has demonstrated excellent clinical efficacy in the treatment of superficial hyperpigmentation, mild-to-moderate chrono- and photoaging, and fine rhytides
• Glycolic acid

  Non-self-neutralizing AHA, keratocoagulation will continue as long as the caustic agent remains on the skin
• Neutralization of glycolic acid

  1. Introduce an alkaline neutralizing agent (e.g. sodium bicarbonate)

  2. Transient increase in warmth, burning, or stinging during neutralization

  3. Skin may be rinsed or cleansed gently after neutralization

  4. Exfoliation typically occurs over several days, reepithelialization complete within 7 to 10 days
• Lactic acid

  Structurally identical to glycolic acid with an additional methyl group, lower pH than glycolic acid, allows for efficient chemoexfoliation at lower concentrations
• Lactic acid has demonstrated comparable efficacy in the treatment of photodamage, superficial hyperpigmentation, and fine rhytides compared to standard glycolic acid peels
• Mandelic acid

  Simple phenolic alpha-hydroxy acid, aromatic glycolic acid with a benzene ring, soluble in water and polar organic solutions, more uniform penetration
• Mandelic acid has demonstrated efficacy in the treatment of superficial erythema and dyspigmentation, as well as efficacy in the reduction of cutaneous sebum production
• Salicylic acid

  Highly lipophilic, easy, rapid, and deep penetration through the lipid barriers of the epidermis
• 30% salicylic acid is often considered the "gold standard" superficial peel for the treatment of acne and has demonstrated excellent clinical efficacy for the treatment of mild-to-moderate inflammatory papulopustular acne vulgaris and comedonal acne
• Salicylic acid

  Self-neutralized by the skin's own endogenous lipoproteins, but cumulative dose exposure remains critical
• Pyruvic acid

  Partially hydrophilic, similar lipophilic and keratolytic properties as salicylic acid but less lipophilic
• Pyruvic acid peels have demonstrated efficacy in the treatment of acne vulgaris and associated disorders of excess sebum production, as well as mild photoaging and superficial hyperpigmentation
• Medium-depth peels

  Allow for controlled keratocoagulation through the dermis and into the papillary dermis, resulting in deeper regenerative changes
• Commonly used medium-depth solutions

  • Salicylic acid (>30%, multilayer application)
  • Glycolic acid (70%, with or without pretreatment primer such as Jessner's solution)
  • TCA (30–50%, monolayer application, with or without pretreatment primer such as Jessner's solution)
• 50% TCA

  Original benchmark for medium-depth chemoexfoliation, high risk of complications including dyschromia, scarring, bacterial superinfection and cutaneous herpes simplex virus reactivation
• Most common chemical agents currently used for medium-depth peeling

  • 70% glycolic acid
  • 35 to 50% TCA, with or without adjuvant combination products (e.g. Jessner's solution or solid carbon dioxide)
  • Multiple layered applications of 20 to 40% salicylic acid and pyruvic acid

  
• Pre-treatment guidelines for medium-depth peels

  1. Mild pre-operative sedation and nonsteroidal anti-inflammatory agents (NSAIDs) to reduce swelling and pain

  2. Proper application technique, avoiding unnecessary, inadvertent reapplication

  3. Peeling face sequentially: forehead to temples first, followed by cheeks and chin, and finally the delicate cutaneous lips and eyelids

  4. Careful feathering of the solution into the hairline and around the rim of the jaw and brow

  5. Particular care when applying to the eyelid

  
• Medium-depth peels

  • Often performed with mild pre-operative sedation and nonsteroidal anti-inflammatory agents (NSAIDs)
  • Higher levels of associated pain
• Applying medium-depth peels

  1. Face peeled sequentially: forehead to temples first, followed by cheeks and chin, and finally the delicate cutaneous lips and eyelids

  2. Careful feathering of the solution into the hairline and around the rim of the jaw and brow

  3. Clinicians should be particularly careful when applying peeling solution to the eyelid, leaving 2 to 3mm of lid margin as a "safety zone"
• Level II to III frosting


  Goal for medium-depth peeling
• Level II frosting is often sufficient for adequate depth of reaction, but deeper Level III frosting is occasionally necessary in areas of thicker skin or heavier actinic damage
• Proper technique allows for uniform and even application, eliminating the need for unnecessary reapplication and the risk of excessive keratocoagulation
• If frosting is incomplete or uneven, the peeling solution should be carefully reapplied to areas of need only
• Most medium-depth chemical peels use a Level II frosting, especially over eyelids and areas of sensitive skin