Ultrasound devices have two principle indications in today’s cosmetic practice: noninvasive skin tightening and noninvasive fat reduction, according to Murad Alam, M.D., M.B.A., a Chicago-based dermatologist and vice president, American Society for Dermatologic Surgery (ASDS).
“Ultrasound energy, which can be used to visualize babies and for other types of imaging, is unusual in that it can penetrate quite deeply into living tissues without causing harm,” Dr. Alam says. “One of the other benefits is you can do treatments with ultrasound in a way that protects the overlying skin and soft tissue. Depending on the type of probe you use, you can decide exactly where in the skin, the subcutis or even deeper, you want to deliver energy.”
Another great thing about ultrasound, he says, is that it’s color blind. Like nonvisible light technologies and radiofrequency, ultrasound is a skin tightening and fat reduction option in darker skin patients, without the worry of dyschromia or hyperpigmentation.
Ultrasound devices to noninvasively tighten skin are options for patients who shy away from surgery and have reasonable expectations.
“Some patients don’t like cutting surgery, even though things like facelifts can be quite effective for the face and… the tummy tuck can be quite effective for tightening excess abdominal skin,” Dr. Alam says.
Ultrasound works by delivering little bits of energy — essentially heat energy — into different layers of the skin. With heat energy, comes skin contraction.
“And that contraction, when you connect the many dots of energy being delivered, causes not just one bit of skin to contract but a whole sheet of skin to contract and allows the area to become tighter,” Dr. Alam says.
Today’s ultrasound devices are able to deliver more energy in a way that’s tolerable for the patient.
“Over time, what we’ve realized is you don’t have to deliver these dots in just one layer, we can deliver them in two or three layers. How closely together we place the dots into layers has increased and how many layers of dots we deliver has increased. By doing so, we’ve become a little bit better at contraction of the area being treated,” he says.
The face is the easiest place to cause skin tightening in because of its ample blood supply and rapid healing.
“But we have learned to change those paradigms of treatment to effectively cause tightening in places off the face — other parts of the body, including the abdomen, arms, knees, etc.,” Dr. Alam says.
Ultrasound devices aimed at reducing fat deliver energy deeper into the body than those used to tighten skin.
“The density of the energy is slightly lower, because you’re treating more volume; you’re not hitting it quite as hard per unit volume,” he says.
There are two major types of technologies that are used for ultrasound treatment of the fat. One is thermal in nature.
“Here, the heating is much deeper in the dermis — it’s into the subcutaneous fat. And that heating causes the fat cells to basically fall apart, and, as a consequence, the area treated has less of a fatty layer after treatment,” Dr. Alam says. “This does require significant heating of the fat and it can be quite uncomfortable as a consequence. So you need to manage patient discomfort during the procedure with appropriate medication.”
The other major method of ultrasound treatment of the fat entails delivering shockwaves, or more of an acoustic effect, according to Dr. Alam.
“By virtue of hitting the fat really hard, the shockwave causes the fat to be mechanically disrupted,” he says. “The good thing about this treatment is this mechanical acoustic effect, which is sometimes called cavitation, is somewhat less uncomfortable because it doesn’t require the same increase in temperature as the thermal effect, which directly coagulates tissue and causes tissue necrosis. Therefore the acoustic effect hurts a little bit less, but sometimes you have to do more treatments than with the thermal device.”
It’s important to manage patients expectations, given ultrasound technology won’t deliver the dramatic outcomes possible with gold standard approaches, like facelifts for skin tightening or liposuction for fat reduction.
“So, patients avoid the cutting and risk of nerve injury and postoperative wound healing, but they settle for a significantly more modest effect,” Dr. Alam says. “Ultrasound is most useful in people who are not very old or don’t have extreme sagging. So, if you’re in your 40s, 50s maybe early 60s and you have a little looseness around your neck, for instance, then you can expect a modest improvement. Within that context, some people get a significant improvement; some people get barely any improvement. Most people will be in the middle.”
Managing expectations for fat reduction is similar.
With liposuction the physician can remove one, two, three or four liters of fat at a time. With ultrasound, the fat removed from an area might be 30, 40 or 50 ccs, he says.
“If you have a patient with 2 or 3 liters of excess fat, it might be prudent to go with the liposuction, rather than getting many, many ultrasound treatments and still not being satisfied,” Dr. Alam says. “If, on the other hand, the patient has a little bit of fat that is not responding to diet and exercise, and doesn’t want to go through liposuction, noninvasive fat reduction by ultrasound might be the right choice.”
Adverse events resulting from ultrasound treatment, whether to tighten skin or reduce fat, are uncommon in frequency and mild to modest in intensity, according to Dr. Alam.
An intraoperative adverse event from thermal skin tightening and thermal fat reduction is discomfort. But that can be avoided with use of benzodiazepines, narcotics or other medications to make the patient comfortable, he says.
“When you’re doing fat reduction with ultrasound, especially with the thermal variant, it is preferred not to treat directly over bony areas because that can cause extreme discomfort,” he says.
Routine outcomes postoperatively are going to be some redness and swelling, which generally abate in a few days. And, if the same area is overtreated, one could theoretically get color and texture changes on the overtreated skin.
“That’s more of a risk on the body than it is on the face, where there’s a better blood supply,” Dr. Alam says. “I think, overall, the safety profile is extremely good — so much so that the risk of adverse events is even lower than with lasers, when it comes to treating people with skin of color or ethnic skin.”
The biggest player in ultrasound skin tightening is probably Ultherapy (Ulthera, owned by Merz Aesthetics), according to Dr. Alam.
Liposonix (Valeant Pharmaceuticals) appears to lead the market in fat reduction ultrasound technology with the thermal effect, while UltraShape (Syneron) is often the device of choice for ultrasound using the mechanical acoustic effect for fat reduction, he says.
The quality of diagnostic ultrasound has dramatically improved during the last 10 to 15 years. Dr. Alam says it’s quite possible that, someday soon, aesthetic physicians will use the technology to better perform cosmetic procedures.
“Historically, ultrasound wasn’t very good at visualizing the skin. You had to look at bigger objects, deeper into the body. Today’s high-resolution ultrasound diagnostic devices continue to be refined to allow us to see thin layers at much higher levels of definition than we could before,” he says. “So, as these technologies get better and become more compact, they could … potentially allow us to perform ultrasound-guided treatment.”