Keratoses senile

Areas of hyperkeratosis (senile keratoses, and flat and seborrheic warts) are a perfect example of this difference in the level of penetration. Keratoses, which are characterized by a localized thickening of the stratum corneum, are less permeable to the acids. Pre-peel preparation with tretinoin evens out the thickness of the stratum corneum and hence the overall permeability of the epidermis. 

Late 30S-40S Early senile lentigines Dyschromia Early actinic keratoses Parallel smile lines Early wrinkling Some foundation worn Mild acne scarring... 

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