NONINVASIVE PROCEDURAL DERMATOLOGY
Introduction
Treatment of Hyperhidrosis With Microwave Technology
Hyperhidrosis is the production of sweat above and beyond normal physiological needs,
regardless of the ambient temperature, and it affects >4% of the population. In addition, a
poll showed up to 21% of the population is bothered on a daily basis by their amount of
underarm sweating. Despite the large number of patients who suffer from hyperhidrosis,
there are relatively few effective nonsurgical treatment options. A new, nonsurgical, lasting
treatment for axillary hyperhidrosis has now been developed using microwave technology
to eliminate sweat glands.
Semin Cutan Med Surg 32:2-8 © 2013 Frontline Medical Communications
Noninvasive Radio Frequency for Skin Tightening and Body Contouring
The medical use of radio frequency (RF) is based on an oscillating electrical current forcing collisions between charged molecules and ions, which are then transformed into heat. RF heating occurs irrespective of chromophore or skin type and is not dependent on selective photothermolysis. RF can be delivered using monopolar, bipolar, and unipolar devices, and each method has theoretical limits of depth penetration. A variant of bipolar delivery is fractional RF delivery. In monopolar configurations, RF will penetrate deeply and return via a grounding electrode. Multiple devices are available and are detailed later in the text. RF thermal stimulation is believed to result in a microinflammatory process that promotes new collagen. By manipulating skin cooling, RF can also be used for heating and reduction of fat. Currently, the most common uses of RF-based devices are to noninvasively manage and treat skin tightening of lax skin (including sagging jowls, abdomen, thighs, and arms), as well as wrinkle reduction, cellulite improvement, and body contouring.
Semin Cutan Med Surg 32:9-17 © 2013 Frontline Medical Communications
Microfocused Ultrasound for Skin Tightening
The demand for noninvasive skin tightening procedures is increasing as patients seek safe
and effective alternatives to aesthetic surgical procedures of the face, neck, and body. Over
the past decade, radiofrequency and infrared laser devices have been popularized owing to
their ability to deliver controlled heat to the dermis, stimulate neocollagenesis, and effect
modest tissue tightening with minimal recovery. However, these less invasive approaches
are historically associated with inferior efficacy so that surgery still remains the treatment
of choice to address moderate to severe tissue laxity. Microfocused ultrasound was
recently introduced as a novel energy modality for transcutaneous heat delivery that
reaches the deeper subdermal connective tissue in tightly focused zones at consistent
programmed depths. The goal is to produce a deeper wound healing response at multiple
levels with robust collagen remodeling and a more durable clinical response. The Ulthera
device (Ulthera, Inc, Meza, AZ), with refined microfocused ultrasound technology, has been
adapted specifically for skin tightening and lifting with little recovery or risk of complications
since its introduction in 2009. As clinical parameters are studied and optimized,
enhanced efficacy and consistency of clinical improvement is expected.
Semin Cutan Med Surg 32:18-25 © 2013 Frontline Medical Communications
New Waves for Fat Reduction: High-Intensity Focused Ultrasound
With the rising demand for body contouring, noninvasive devices for fat reduction have
become increasingly popular and have grown dramatically over the past decade. Highintensity
focused ultrasound (HIFU) has been used for nearly half a century for the
noninvasive treatment of tumors of various organs, but has only recently been evaluated as
a method for the selective destruction of adipose tissue. HIFU works by ablating subcutaneous
adipose tissue and causing molecular vibrations that increase the temperature of
local tissue and induce rapid cell necrosis. Several studies reveal the safety and efficacy of
HIFU for fat reduction in the abdomen and the flanks. These studies indicate consistent
reduction in abdominal circumference >2 cm after a single treatment. The adverse events
are limited to transient tenderness, bruising, and edema. Increased utility of HIFU for fat
reduction will likely increase over time.
Cryolipolysis: A Historical Perspective and Current Clinical Practice
Dermatologists have long used cold-based therapeutic approaches for a variety of applications.
Based on the differences in chemical composition, it is possible to selectively
target certain tissues rich with lipid, while sparing the surrounding tissue predominantly
containing water. With historical observations of cold-induced panniculitis suggesting the
feasibility of this strategy, cryolipolysis has emerged as a new methodology using controlled
cooling to selectively target fat. Both preclinical and clinical studies have established
the safety and efficacy of cryolipolysis for noninvasive body contouring. This review
will focus on the evolution of cryolipolysis from initial case reports of cold-induced panniculitis,
to preclinical and clinical studies, and the current clinical practice.
Semin Cutan Med Surg 32:31-34 © 2013 Frontline Medical Communications