Why carry out this study?

Inflammatory skin conditions present a significant burden and affect millions worldwide as existing pharmacological and device-based therapies often have poor efficacy and unwanted side effects.

This report aims to understand the bioeffects of moderately dosed 20 MHz high intensity focused ultrasound (HIFU) on the upper layer of human skin, and compare it to cryotherapy commonly used in dermatology, as preclinical studies suggest that HIFU can induce immunogenic cell death and immune sensitization, potentially leading to generalized lesion regression and thereby a new modality for treatment of inflammatory skin conditions.

What was learned from the study?

The numerical modelling analysis shows that the moderate levels of HIFU can accurately target the upper dermis, creating extremely localized necrotic volumes several times smaller than those generated by conventional liquid nitrogen cryotherapy.

Clinical results from a single patient with the inflammatory skin disease granuloma annulare (GA) confirm the efficacy of HIFU treatment, showing full or partial recovery with reduced scarring and dyspigmentation compared to cryotherapy.

The study concludes that HIFU treatment slightly below the threshold for ablative response presents significant advantages over cryotherapy for treating inflammatory skin conditions, including reduced scarring and dyspigmentation.