ENERGY BASED AESTHETIC MEDICAL DEVICES
Aesthetic Medical Device industry include both fillers, implants and mechanical liposuction equipment among a few other things but in terms of power operated equipment, the industry has truly gone through large technological advances within the last decade or so.
Initially, the devices of this type were mostly found at the Dermatologists clinics and were focused on treating skin diseases and conditions such as moles, vitiligo, pigmentation issues and scars, usually using laser and/or light technologies. Over the last decade or so, newer, more efficient and safer laser technologies and light therapies have emerged, as have other technologies such as electroporation, ultrasound, radio frequency, direct heat and cryo-therapies.
What is common to most of the newer power operated aesthetic medical devices is the move towards less invasive procedures. In fact, most of the newer technologies are non-invasive (no incisions) or minimally invasive (very small incisions) that offer much less traumatic approaches, better/quicker healing and are less painfull and require much less down time from the patient.
Energy based Medical Devices can treat many body issues!
These therapies are directed at multiple aesthetic indications and conditions focused on treating:
Safety is pivotal – training and certification are essential
While some of the earlier generation technologies were pioneering, risky and at times even harmful with variable success, the newer technologies with proper clinical documentation and regulatory environment have proven to be much more safe, effective and providing lasting results to the patients both in terms of the technologies as well as treatment protocols applied.
Ensuring that the specific technology in question is both EU certified and FDA (US Food and Drug Administration) certified will provide assurance of quality and safety. Be aware of the copycat technologies and technologies that do not carry certification from reliable sources as these despite usually very low prices can be ineffective at best but dangerous at worst to the patients.
Also, it is important that the person giving treatment is qualified to do so. Having taken proper training and certification for the use of the equipment is important and patients can ask for the proof in form of certificates/other documentation such as health authority licenses, etc. what ever is the standard in the given country.
Closer look at the Mechanism of Action
While the non-invasive technologies to approach the above issues may be different, there are ultimately three modes of action:
- Optical light/color wavelengths for treating discoloration, unwanted scarring discoloration, veins and hairs
- Skin ablation/controlled surface injury to stimulate collagen production and improve skin quality and reduce scar impression
- Thermal/skin regulation (cooling or heating) to treat fat cells and to do body & face contouring. Skin tightening pertains only to heat derived devices
Looking at electromagnetic spectrum we can see where different technologies are active. While the radiation on the left end of the spectrum (X rays and cosmic rays including UV from sun) is dangerous for our bodies in excess quantities and frequencies, radiation gets milder and milder moving towards right on the spectrum. At the right end is infrared radiation that in lower quantities is quite harmless but as it is very water absorbable and non-selective/dispersed as to targets, it also gets harmful to human bodies that consist 70% of water at higher quantities. In terms of medical aesthetics equipment, the lower safety limit is in general seen to be around 500 nm and go up to a few thousand nm.
Our bodies act differently to different wavelengths. For example, while around 755 nm is effective in treating light/blond hair types on light skin types, 810 nm or even more is needed for darker hairs and skin tones. Dark spots and discolorations (melanin) as well as hemoglobin (more superficial smaller blood vessels) are destroyed best at 500-600 nm wavelengths but the skin tone is crucial in choosing the right length – the darker the skin the higher the wavelength needed.
Technologies at work – Radio Frequency
The application of RF energy in medicine is well established. As such, RF is the basis of magnetic resonance imaging (MRI) and surgical diathermy, both commonplace applications being used millions of times per year in hospital practice. In cardiology, RF is used for ablative interventions, for example, ablation of accessory conduction pathways, and in oncology/oncological surgery for tumour/metastasis ablation. Since 2000, RF treatments have been increasingly used in medical aesthetics, owing to their their versatility, efficacy and safety.
RF is a part of electromagnetic spectrum where it’s frequency range depends on industry. In medicine the RF (radio-frequency) energy is an alternating electrical current in a frequency range of 100kHz – 6MHz. Pure controlled thermal effect is important as at lower frequency there is nerve stimulation and at higher frequency there is more radiation and less localized RF (which is very much wanted for precise treatment).
RF works by electrical current conducted by the tissue. This increases ion collision and creates kinetic energy. This kinetic energy is transformed to thermal energy (heat), which causes controlled damage to skin tissue. The damage triggers natural healing mechanism resulting in tissue renewal (collagen, elastin, HA) and regeneration (thicker dermis).
Radio frequency has many benefits in aesthetic medicine as the source of energy. It is relatively easily created and with bipolar technology well controlled and safe. Due to the heat creation it makes an excellent medium for not just fat cell destruction, body and face contouring but also skin tightening and other indications such as acne and scar management (if built into the device).
Other technologies such as Ultrasound and Cryo-therapies can be effective to certain extent in either addressing flaccid (flabby) skin or killing fat cells but not both at the same time like RF technology does. This combined with the fact that RF is in general a very versatile technology that can be used for multiple aesthetic medicine indications makes it a cost effective and preferred technology that is most utilized technology in aesthetic medicine and also specifically compared to the above two technologies.
There are two forms of RF
- Radiation RF that is radiating from a distance with no contact with the skin.
- Conductive RF whereby the electrodes have to be in contact with the skin. There are 2 types of conductive RF:
- Monopolar – one electrode is touching the skin and the other one is held by the hand or tied to the back. The electrical current then flows through the body.
- Bipolar or multipolar – both/all electrodes are touching the skin and the area of current flow is limited.
Radiation and monopolar RF penetration depth into the body is not controlled, neither is the amount of electrical energy that is passing in various body areas. The bipolar RF has a controlled penetration depth, as well as energy input and thus the most desirable form to be used.
Fractional technologies can be classified as ablative (penetrating skin surface) or sublative (no skin penetration). Using electromagnetic power will allow development of heat which is good for skin tightening while ablation allows skin resurfacing (and smoothening) as well as wrinkle reduction/removal. Different technologies are utilized to obtain sustainable results as can be seen below.
It appears that the best results are obtained by using both ablation and heat as this allows simultaneous benefits of resurfacing/smoothening and stronger, younger skin while combining tightening of the skin at the same time. Fractional technologies at sufficient depth can also be excellent in cellulitis management as well as stretch mark management and have well documented clinical evidence for excellent and effective acne management both active acne and scars.
Laser technologies can be either light sourced or electricity sourced and use mirrors to channel and focus the beam. This technology can be categorized according to the delivery mechanism of the beam:
- Crystal/solid beam that is safe but has a low efficiency (1-3%)
- Diode/semi-conductor with excellent efficiency (40-50%)
- Gas/CO2 with medium level efficiency (10-20%)
- Dye/liquid beam with quite low efficiency (0.5%)
All but diode lasers need to be contained in large boxes while diode can be contained in small spaces including hand applicators that with high efficiency makes this laser beam most desirable for aesthetic medicine use.
Laser technologies can be very effective in terms of precision ablation (small treatment areas such as moles, birth marks) as the rays are coherent and concentrated because it is a single wavelength. This is also why the laser beam is very bright.
The bright beam may be directed through Eye protection: lasers in far frequency IR like CO2 or Erbium, are not so dangerous since they are absorbed in the cornea and not much is left to harm the eyeball and lens. Near/lower frequency IR is dangerous because is not optimally absorbed in water therefore will not be absorbed in cornea, it will go through the eye lens which will focus it to the retina and create a blind spot. Therefore eye protection goggles are critical part of the laser treatment both for the patient and for the healthcare professional treating the patient.
Hair removal is the largest area of usage for lasers. Melanin in the hair shaft absorbs the light, which is transformed to heat. This heat is conducted to the surrounding follicular cells and damages them. The hair is detached from follicle and comes out after 1-2 weeks. The damaged follicle is gradually replaced by non-functional internal scar tissue. This leads to gradual reduction on the hair production and ultimately permanent removal.
Permanent hair removal requires multiple treatment rounds as the hair growth cycle is individual for each hair and the laser beam needs to capture the hair at the right time of the cycle in order to damage the follicle. Number of treatments varies between the individuals based on their DNA, number of hair follicles and hair growth pace.