Related Experiment Video
Updated: Aug 6, 2026

Visualizing Scar Development Using SCAD Assay - An Ex-situ Skin Scarring Assay
Published on: April 28, 2022
Histologic study of depressed acne scars treated with serial high-concentration (95%) trichloroacetic acid
Anthony Yug1, Joshua E Lane, Michael S Howard
1Division of Dermatology, Department of Internal Medicine, Mercer University School of Medicine, Macon, Georgia, USA.
Background:
Acne scarring is a common manifestation that remains a therapeutic challenge to dermatologists, dermatologic surgeons, and plastic surgeons. Although multiple therapeutic modalities exist, treatment often remains inadequate. The use of high-concentration (95%) trichloroacetic acid (TCA) applied focally to atrophic acne scars has been described.
Objective:
The current study confirms the utility of focal application of 95% TCA to acne scars in addition to a histologic examination of this technique.
Methods:
Acne scars in three patients were treated with focal 95% TCA by serial application. Wooden applicators were used to apply TCA focally and repeated at 6-week intervals for a total of six treatments. Punch biopsies were performed at baseline and at 1 year postoperatively. Histologic examination was performed with routine hematoxylin/eosin, Masson trichrome, and Verhoeff-van Gieson staining.
Results:
Clinical examination revealed apparent cosmetic improvement in both depth and appearance of acne scars. Patient satisfaction was high. Histologic examination demonstrated a decrease in the depth of acne scars. In addition, increased collagen fibers and fragmentation of elastic fibers were noted. There were no complications from the procedure.
Conclusion:
Focal application of high-concentration TCA to atrophic and "ice-pick" acne scars appears to produce clinical improvement. Histologic changes of this technique are described.

