Research Article: 20-MHz high-intensity focused ultrasound for tattoo removal without pigment-specific optical targeting and with evidence for an ablation-associated transepidermal extrusion pathway
Abstract:
Radiotherapy tattoos can impose a cosmetic burden, while laser removal requires selection of optical wavelengths according to the absorption characteristics of individual tattoo pigments. We evaluated a handheld 20 MHz high-intensity focused ultrasound (HIFU) device as a potential non-optical approach to reducing red, black, and blue tattoo pigments.
Thermal injury zone (TIZ) geometry was characterized ex vivo in avian muscle and full-thickness porcine skin tissue. Rat dot tattoos (red/black/blue) received a single-session exposure (10 shots; 6 W, 1,000 ms) and were followed for 21 days with histology and morphometry. In Yucatan minipigs, multispectral 3D imaging quantified acute (minutes) and chronic (Day 4–98) responses in normal and tattooed skin, and was extended to multicolor tattoos with >100-day follow-up. A pilot substudy applied a hydrocolloid dressing.
Ex vivo TIZs scaled with energy, with restricted axial expansion in porcine tissue. In rats, frosting progressed to crust formation (Days 7–14) and pigment lightening by Day 21; pigment debris was observed near the dermo-epidermal junction and within crusts, consistent with transepidermal elimination. TIZ depth decreased from 730 ± 196 ? m at 1 h to 362 ± 125 ? m at Day 21, while peripheral ring-like traces were noted in some sites. In minipigs, tattoo contrast decreased (? E * a b 9.87 ? 3.30 by Day 98), and similar contrast reductions were observed across red, black, and blue tattoos by Day 101–105. Hydrocolloid coverage was associated with earlier eschar detachment and faster normalization by Day 14.
These feasibility data suggest that 20 MHz HIFU may support an ablation-associated transepidermal extrusion pathway for reducing red, black, and blue tattoo pigments without requiring pigment-specific optical wavelength matching. The findings provide preliminary histology-linked and imaging-supported evidence for this non-optical tattoo-treatment approach, while underscoring the need for larger controlled studies and dose optimization to improve cosmetic outcomes and minimize residual traces.
Introduction:
Radiotherapy tattoos can impose a cosmetic burden, while laser removal requires selection of optical wavelengths according to the absorption characteristics of individual tattoo pigments. We evaluated a handheld 20 MHz high-intensity focused ultrasound (HIFU) device as a potential non-optical approach to reducing red, black, and blue tattoo pigments.
Read more