In medical aesthetics, transdermal devices, or penetration enhancers, that use microneedles, rollers, dermoelectroporation and other novel modalities offer practitioners an efficient and minimally invasive technique to penetrate the skin barrier. But while practitioners have eagerly embraced these products and devices, few therapeutic or regulatory standards exist.
Physicians initially used these systems for skin rejuvenation procedures; however, after years of refinement, the devices now address many indications, such as acne scars and other scar types, hair loss, cellulite, fine lines and wrinkles, pigmentary problems, axillary hyperhidrosis, actinic keratosis in photodamaged skin, skin tightening and more.
These technology improvements have established microneedling as the predominant transdermal delivery method in most aesthetic practices. In addition, practitioners combine transdermal delivery technologies with surgical and nonsurgical procedures to enhance results.
Microneedling introduces a controlled wound into the skin, improving the ability to deliver drugs, sera and energies (radiofrequency, ultrasound, laser and CO2) across the skin barrier, bypassing the stratum corneum, into the vascularized dermis.
Treatments, especially with automated devices, have therefore become quite popular, having been anecdotally shown to be quite safe and providing exceptional results.
“Anecdotal” is the guiding word here though, as there are only a few FDA-approved devices on the market and hardly any high-quality clinical studies have been published when it comes to microneedling. In addition, some manufacturers have been notoriously deceptive in the marketing of devices and procedures in this genre, at times relying on misleading terminology, such as so-called infusion techniques, resulting in a kind of “Wild West” feel to the product category as a whole.
“The trend in this market is that people think microneedling and transdermal methods are the holy grail,” stated Michael Gold, M.D., dermatologist and cosmetic surgeon, and founder of Gold Skin Care Center in Nashville, Tenn.
“Any hole you put in the skin can be used for drug delivery,” he began. “For instance, when we treat hypertrophic scars, if we’re able to put drugs in after a fractional injury, or during skin treatments with a needling device of any kind, we are putting something sterile into the skin. These types of procedures can provide a definite benefit, in my experience. But while early clinical data suggests that these treatments may help, we don’t have any definitive data yet.”
According to Garry Lee, M.D., an aesthetic specialist in Las Vegas, Nev., “We are seeing an increase in patients seeking nonsurgical cosmetic treatments with less downtime and cost than plastic surgery. Microneedling adds value to those procedures. There is a saying in the industry that microneedling is the ‘poor man’s laser,’ which is emphatically true since the results can be dramatic for skin rejuvenation at a fraction of the price of most laser systems.”
Radiofrequency (RF)-based microneedling and other transdermal systems that utilize energy have emerged as a top choice among practitioners, noted Edward M. Zimmerman, M.D., a cosmetic surgeon in Las Vegas, Nev.
“While RF microneedling has become a trend regardless of what system you use, that and topical RF may have reached its apex in terms of what we can actually do with it,” he stated. “Even if we make the electrodes bigger so we can get a little bit more depth out of a monopolar system, it is a transient improvement in the appearance of skin texture and tightness.”
Advanced microneedling platforms are starting to appear in the marketplace, which go far beyond the earlier monopolar, unipolar and bipolar approaches.
For instance, the big box Vivace system from Aesthetics Biomedical (Phoenix, Ariz.) operates with 36 insulated, gold-tip needles and a robotic step motor that creates fast and even insertions into the skin. The robotic depth settings offer 31 precise, multilevel adjustments down to an exact depth of 3.5 mm at 0.1 mm increments. In addition, the system’s RF-based energy delivers heat evenly as it performs skin tightening, while reducing redness, hot spots, burning and patient discomfort.
Such advanced microneedling devices have benefited from improved motors, expressed Farhan Taghizadeh, M.D., medical director at Arizona Facial Plastics (Scottsdale and Phoenix, Ariz.).
“The advantage of superior motors is that you can create finer channels with better control,” he expressed. “By accelerating the motors on these devices, they are able to stamp very rapidly. It used to be you could only do a little bit of stamping, but now you have almost machine-gun accuracy with very rapid techniques that allow you to cover larger surface areas.”
Another cutting-edge variation on traditional RF-based technology is available in the Secret RF from Cutera, Inc. (Brisbane, Calif.). This system induces dermal remodeling by applying precisely controlled RF energy directly into various depths of skin from 0.5 mm to 3.5 mm via minimally invasive microneedles, sparing the epidermis and reducing patient downtime. Its dual handpieces and two treatment tip sizes (25- and 64-pin) allow physicians to treat patients quickly and efficiently in under 20 minutes.
According to Dr. Zimmerman, the evolution of microneedling will rely on combination therapies. “For instance, combining microneedling with plasma resurfacing, to achieve better neck tightening,” he indicated. “I’ve used helium plasma under the subdermal and added RF microneedling to the top and observed a pretty profound tightening effect. While plasma energy probably doesn’t go very deep, you might be able to go deeper with RF microneedling and get some of the subdermal tissue to contract, as well. We’re not just tightening the subdermal, but also tightening the fascial covering and the interstitial bonds between the dermis and fascia, which pulls tissue tighter.”
The combination of nonsurgical off-label procedures, which includes microneedling, can create synergy for better overall results, reported Dr. Lee. “Microneedling and platelet-rich plasma (PRP), for instance, are clearly one of the great combinations, albeit currently off-label, for skin rejuvenation and treating atrophic scars.”
PRP is often used as a transport medium for other materials, added Dr. Taghizadeh. And while PRP and platelet-poor plasma (PPP) have been established as valuable in transdermal delivery devices, “more recently we have started seeing advanced growth factors, amniotic products and umbilical stem cell products, which are better quality and beginning to supplant PRP.”
Other emerging product types utilize micronized horse collagen, which has no hypersensitivity to humans, as an adjunct therapy to devices.
On the horizon we will continue to see more combinations of transdermal applications, such as hyaluronic acid (HA)-based fillers and materials like fibroblast-derived growth factors or distinctive types of stimulating molecules. These will be applied in both topical and transdermal therapies, often as ready-made products to be used in conjunction with transdermal devices.
For instance, the Transderm Ionto DEP System from Mattioli Engineering Corp. (Arlington, Va.) is a patented, FDA-cleared device that allows practitioners to inject drugs (including lidocaine, HAs, neurotoxin, steroids or vitamins), as well as proprietary formulations and regenerative therapies like growth factors and PRP.
AQUAGOLD from Aquavit Life Sciences, Inc. (Las Vegas, Nev.) uses a patented, gold-plated hair-fine needle system to painlessly deliver custom solutions into the skin at the ideal 600 micron depth. It can be combined with a variety of sera and materials, such as micro Botox and HA-based gels, and can enhance laser treatments with micro sera containing growth factors.
Another interesting transdermal technology, Jet Volumetric Remodeling (JVR), goes in a completely different direction by employing a needle-free intradermal compound delivery method. This technology is currently available in the EnerJet2.0 system from PerfAction Technologies (Rehovot, Israel).
Thulium lasers are making their way into the transdermal delivery space, as well, stated Dr. Taghizadeh. “This laser platform uses a micro-ablative frequency that is incredible for product delivery. While you can use CO2 for product delivery, there seems to be something very unique about the thulium laser in terms of its ability to really control the depth and the fine nature of the channel that is created.”
Another emerging technology trend involves the latest in so-called infusion technologies – micro-infusion, which has emerged in Europe in product form as a kind of handheld “dermal gun” that uses very fine needles to stamp growth factors and other products into the skin. “I think this is going to be very significant. These have accelerated mechanisms that work very rapidly,” Dr. Taghizadeh conveyed.
In combining cell-based and other materials with transdermal devices, physicians must be extremely careful, cautioned Dr. Gold.
“Keep in mind, for instance, that PRP has no FDA approval for skin, because it is your own plasma,” he explained. “You’re taking a non-FDA approved substance that we all know works and combining it with a delivery system. If you aren’t delivering something sterile through that channel you are playing with fire. I’m not aware of any growth factors or stem cells outside of PRP that are sterile. We have rollers, pens, microneedling devices with RF pins or needles and they all have the ability to do this.
Then you have fractional non-ablative and ablative lasers, and all of these can also be used for drug delivery. Physicians do this all the time but it is all experimental. Nobody has done the clinical work to make it commonplace or approved.”
The lack of true therapeutic and regulatory standards has unfortunately constrained the microneedling / transdermal segment. “Keeping up with the FDA is the challenge, as increasing requirements make older microneedling devices obsolete,” stated Dr. Lee.
Additionally, many microneedling-based pens and other devices are manufactured outside of the U.S., Dr. Lee added. “And while it is tempting for practitioners to adopt these offshore products, one thing to watch out for is maintenance support, as I’ve heard stories of devices from other countries which had tremendous repair delays due to the distance,” he said.
Currently, the SkinPen® from Bellus Medical (Dallas, Texas) is the only FDA-cleared handheld microneedling device made in the U.S. It has a limited indication for the treatment of facial acne scars, and comes packaged with synergistic adjunct products, including a light-activated cream and PRP systems.
Regardless of the device’s make and model, there are key points that physicians need to know to avoid complications.
“Extreme care must be taken when microneedling around the eyes to prevent any damage to the patient’s vision,” Dr. Lee advised. “While I don’t think inserting an eye shield is necessary, I do recommend patients close their eyes. Practitioners must also make sure the settings are at the appropriate depth for each area treated, so as to prevent unnecessary complications.”
“The biggest issue that I’ve seen is when people put non-sterile creams and lotions on skin afterwards,” Dr. Gold reported. “That is inappropriate. There is so much in the world of drug delivery that is not validated, thus protocol standards do not exist, and as long as these protocols don’t exist, it is all experimental.”
As a part of creating standards, microneedling technology needs to include better feedback mechanisms, said Dr. Zimmerman. “With microneedling, you put energy down into the skin layers and bring that tissue to a certain temperature for a certain period of time. We need real-time feedback because we’re just delivering energy and don’t know if it is enough, too much or too little.”
Eventually, it may be left up to the physician to solve this problem in a reliable way, Dr. Zimmerman added. “Either become more skilled or get an ultrasound technician to obtain a high-resolution image, in order to determine how much energy is really needed from different modalities. That may be the next standard of care. Instead of going on blindly, we would actually perform real-time monitoring to avoid hematomas or problems that we are unaware of during the procedure.”