Can you remove tattoo with ultrasound?

- Introduction to High Intensity Focused Ultrasound (HIFU) for therapeutic applications.

In recent years high intensity focused ultrasound (HIFU) has been established as an effective modality for treatment of a large variety of medical indications such as prostate cancer, uterine fibroids, Parkinsons / Essential tremor, glaucoma, thyroid cancer, etc.

Its basic mechanism is similar to using a magnifying glass to focus light. Instead of concentrating light, HIFU however uses a concentrated beam of ultrasound waves generated by focused acoustic transducer, targeting a specific focal point. In contrast to light beams, the ultrasound can pass through tissue with little effect. When the ultrasound reaches its focal zone, where the beam converges, the energy density is greatly intensified, and thereby induces phenomena of two kinds. One is a thermal response manifested by a rapid temperature rise and another being of mechanical nature, namely cavitation.

Depending on the settings of the treatment, one can tailor the physical response to cause reactions from mild localized overheating of the focal zone to full coagulative necrosis and irreversible cell death. The method can therefore be used as a non-invasive way to treat features inside the human body without any form of surgical procedure or puncture of the skin surface.

TOOsonix is a Danish company established in 2017 with the mission to help people by use of high frequency ultrasonic therapy. TOOsonix has develop a unique technology allowing operation of HIFU therapy instrumentation in high frequency range (above 10 MHz). It has been the enabler for applications where a very precise and well defined HIFU focal zone is the key, such as dermatology, cosmetology and small animal research. TOOsonix has already identified over 25 medical and non-medical indications, where its technology will help overcome drawbacks of the currently available instrumentation which is generic and lacks the sharp focus, one being tattoo removal.

The lecture will introduce the concept of high intensity focused ultrasound and it will present the overview of its current applications in medicine. Furthermore, it will cover the basics of HIFU including fundamentals of non-linear acoustics, ultrasonic transducers as well as acoustic characterization methods. A number of analytical and experimental results will be presented for HIFU therapy operating at frequencies of around 20 MHz obtained using TOOsonix System ONE-R.