The Effects of Oral Isotretinoin on Atrophic Acne Scars Measured by Shear-wave Elastography: An Observational, Single-center Study.

Background: Although the effects of oral isotretinoin (OI) on acne vulgaris and preventing further acne scars have been well-documented, the specific impact of OI alone on pre-existing atrophic acne scars (AAS) remains unclear. No clinical study has objectively evaluated the effect of OI on AAS yet.

Objective: We sought to investigate the OI effect on AAS quantitatively and reliably by shear-wave elastography (SWE).

Methods: This work is a single-center, prospective and observational study. Thirty patients with moderate and severe acne vulgaris accompanied by AAS were included. We started the OI with a standard dose regime. On Days 0 and 90 of treatment, patients' global acne grading system (GAGS) and the Goodman and Baron's Qualitative Global Scar Rating System (GSRS) were evaluated. The dermal thickness, subcutaneous tissue thickness, scar size, and scar and subcutaneous tissue's elastic modules were measured on both cheeks of each patient by SWE.

Results: The improvement in GSRS stages and GAGS scores in 90 days were statistically significant (respectively; =0.029, <0.001). Scar size and dermal thickness decreased, while the subcutaneous tissue thickness and the elastic modulus of scar and subcutaneous tissue increased in bilateral cheeks. The thickness changes in the right side dermis, and subcutaneous tissue on both sides were noteworthy (<0.05).

Conclusion: Besides its well-known effect on acne vulgaris, OI also could be an effective treatment option for reducing scar size and severity while improving skin elasticity. SWE may help follow skin and scar properties.