THE FUTURE OF ULTRASOUND

By: Dr Benjamin ASCHER and Dr Peter VELTHUIS

At this moment, none of the ultrasound devices that are used for facial ultrasound imaging have been developed with the specific application in cosmetic medicine and surgery in mind. This is reflected in the lack of presets and probes truly for our specialty on any of the machines. As the market for ultrasound in cosmetic medicine is new but growing, it is likely that suppliers will be interested in the needs of our doctors. However, is it already clear what this is about? 

Targeted injections of fillers, botulinum toxins and threads

The newly developed ultrasound-guided injection probe will be a game changer. For botulinum toxin this is clear, since adverse events have been described with improper placement1 Also more precise injection techniques lead to better outcomes. During injection of fillers many surprising phenomena may occur. Back-flow of the filler along the shaft of a needle or cannula is seen very frequently. Also, inadvertently placement of filler in the wrong layer or in a vessel may happen. Filler material has frequently been detected in the SMAS. It may be caused by back-flow, when delivering filler on the periosteum. But it can also occur that an injector aiming to deliver filler on the periosteum does feel the bone at the tip of the needle/cannula, but in reality, did not pierce the SMAS completely. When injecting, filler is delivered in between layers of SMAS, where it may lead to nodule formation. Because of the very thin subcutaneous fatty layer in the pre-auricular area, filler material is quite frequently injected in the parotid gland. By injecting under ultrasound guidance blood vessels can be avoided, leading to less bruising or more importantly less intravascular injections. In a global population of 250,000 injecting physicians, each performing 800-1,000 treatments yearly, the risk of vascular conflict has been estimated at a minimum of 30,000 cases per year2) Finally it is thought that, when hyaluronidase is used to dissolve hyaluronic acid filler, intense mixing of the enzyme with the HA filler leads to a much better outcome. Ultrasound guidance during injections of hyaluronidase is therefore strongly advised. 

Detect and classify any pre-existing product or device (fillers, thread, prothesis, etc.)

It's important to note that the use of ultrasound for facial injections typically involves imaging and guidance rather than the injection process itself. The possibility by experience to detect previously injected materials will become a must to avoid complications and increases safety for our patients. 

Increased frequencies to improve superficial resolution

Higher frequencies give better resolutions in the superficial layers than lower ones. However, these high frequencies do not penetrate deep. So, there must be an optimum in megahertz number. Clearly the ultrahigh-frequencies (>50MHz) are impractical in every day cosmetic practice and primarily suited for research. Having worked with transducers up to 24 MHz, the authors can relate that all of these high numbers still perform very well in cosmetic injectable practice. At the opposite, the ultra-high frequency ultrasound from 50 to 100MHz, can be used for methods of objectification of epidermis results after injections, in clinical trials, coupled with optical biopsies, microvascular doppler, and data science.3

Increased performance of the processor and monitor

The final image displayed on the monitor results not only from the performance of the transducer but also from the quality of the processor and the monitor. When developers gain a better understanding of our needs, we will probably obtain more tailored solutions. For instance, surgeons might benefit from increased visibility of nerves, maxillofacial surgeons from better definition of structures located at a depth of 3-5 centimeters and laser specialists from more resolution of structures in deep dermis and superficial subcutis. Application of artificial intelligence (AI) is a realistic option in the near future. Giving colors to different tissue layers is an application that has already been tested experimentally. This may help in education, but also in clinical practice. AI may aid in identifying filler complications, but also in other types of pathology or anatomical variations, that may interfere with clinical & cosmetic procedures. In a parallel way echogenic needle, motion gesture, and voice control need to be developed in our profession. 

Application to fat injections

In addition, on both sides of the Atlantic4,5,6 in the case of fat injections into the buttocks, called superficial gluteal lipofilling, (BBL, Brazilian Butt Lift), different medical authorities have given the following guide lines: these injections can only be injected into the subcutaneous space and must never cross the fascia overlying the gluteal muscle fascia. Intramuscular or submuscular fat injections are prohibited. The surgeon performing the procedure must use ultrasound guidance when placing and navigating the cannula and injecting fat into the subcutaneous space to ensure that the fat is placed above the fascia overlying the gluteal muscle. The surgeon must also maintain the ultrasound video recordings in the patient's medical record including with the time and the date stamp of the ultrasound video recording. Our vision is that parallel official & legal recommendations become the norm in the case of cosmetic toxin injections and fillers injections in the face and the body. So, our population of practitioners must be perfectly well trained in the use of ultrasound in cosmetic medicine and surgery. 

Repost from: https://www.imcas.com/en/academy/blog/1038/the-future-of-ultrasound