Efficacy and safety of noninvasive focused ultrasound for treatment of subcutaneous adiposity in healthy women

[The impact of diabetes on aesthetic procedures]

Diabetes may have an impact on aesthetic medicine, influencing both the safety and efficacy of various aesthetic procedures. Key aspects of the impact of diabetes on aesthetic medicine are summarized. Individuals with diabetes often experience dry skin, a condition known as xerosis, which may affect the overall texture and appearance of the skin. Diabetes can compromise the immune system, making individuals more susceptible to skin infections. Aesthetic procedures involve the introduction of foreign substances, and compromised skin integrity may heighten the risk of infection. This underscores the importance of strict hygiene and postprocedure care to minimize the risk of complications. Delayed wound healing can be a significant concern in aesthetic procedures where incisions, injections, or other manipulations are made, as impaired healing may affect the final outcome and increase the risk of complications. Collagen metabolism, affecting the elasticity and structural integrity of the skin, may influence the long-term results of procedures such as dermal fillers, where collagen plays a crucial role in maintaining skin volume and firmness. Diabetes is linked to vascular complications, including poor blood circulation, which may have implications for procedures like laser treatments or other interventions that rely on adequate blood supply for optimal results.

Non-invasive Body Contouring Technologies: An Updated Narrative Review

INTRODUCTION

Nowadays, a lot of body contouring devices and methods are introduced all over the world. The object of the present narrative review was to update and classify existing evidence on these methods and devices.

METHODS

We searched databases including PubMed, Cochrane, and Google Scholar for 11 essential keywords, including cryolipolysis, high-intensity focused ultrasound (HIFU), shock wave, low-level laser therapy (LLLT), radiofrequency (RF), capacitive resistive electrical transfer (TECAR), high-intensity focused electromagnetic (HIFEM), electromyostimulation (EMS), carboxytherapy, mesotherapy, and acupuncture and their abbreviations, in addition to obesity, overweight, cellulite, subcutaneous fat, and body contouring.

RESULTS

Totally 193 references were used in 11 main topics.

CONCLUSION

In order to help physicians with finding the best evidence in different methods, the data were summarised in 11 topics. Furthermore, FDA-approved devices, side effects and common protocols were described in each section.

LEVEL OF EVIDENCE I

This journal requires that authors 39 assign a level of evidence to each article. For a full 40 description of these Evidence-Based Medicine ratings, 41 please refer to the Table of Contents or the online 42 Instructions to Authors www.springer.com/00266 .

Focused Ultrasound for Dermal Applications

Focused ultrasound (FUS) is emerging as one of the most promising, non-invasive treatment techniques. The advancement of transducer technology has paved the way for dermatological applications. A comprehensive review is presented for healthcare practitioners and researchers, summarizing the effect of various operational parameters on the injury zone produced by ultrasound beams for various dermatological applications, which include skin tightening, fat reduction, hyperpigmentation and cancer treatment. In this article, we aim to highlight the efficient operational parameters of FUS to enhance pain relief during surgery and its affordability for skin treatment. Finally, a prospective future technique for efficient FUS is discussed.

Effectiveness of HIFU Therapy for Nonsurgical Facial and Body Contouring: A Systematic Review of Prospective and Experimental Studies

BACKGROUND

Liposuction, the most common body sculpting surgical procedure known today is associated with the risk of numerous complications. A safer and more noninvasive approach involves the use of high-intensity focused ultrasonography (HIFU) lasers, which work by selectively damaging fat tissue through apoptosis or necrosis induction of fat cells. The authors' systematic review was designed to identify the effectiveness of HIFU for nonsurgical facial and body contouring.

METHODS

An exhaustive literature search was conducted of the PubMed/MEDLINE, Cochrane Central, Scopus, and EBSCO electronic databases for the period from November of 2005 to July of 2020. The full text of selected articles was reviewed for possible study inclusion, and articles fulfilling the inclusion criteria were recruited. Characteristics of the included studies were noted, and outcomes were assessed. Assessment of quality and risk of bias was performed for all the studies using the RevMan tool and the methodological index for nonrandomized studies.

RESULTS

The initial search revealed a total of 4584 citations, of which only 11 were included in the present review: nine used HIFU for recontouring of the abdomen and only two used HIFU over the face and neck. Studies evaluated either the efficacy of HIFU or the safety of its use. The average total energy ranged from 140 to 248 J/cm 2 for the abdominal region and 0.3 to 1.2 J/cm 2 for the face and neck. The focal depth ranged from 1.1 to 1.8 cm. All the studies showed promising results with the use of HIFU.

CONCLUSION

HIFU therapy is safe, effective, and minimally invasive, with predictable results when used for body and facial recontouring.

Metabolic changes after nonsurgical fat removal: A dose response meta-analysis

BACKGROUND

Obesity-induced insulin resistance leads to the metabolic syndrome. Both bariatric surgery and surgical fat removal have been shown to improve metabolic health, but the metabolic benefits of nonsurgical fat removal remain uncertain. The aim of this paper is to establish whether nonsurgical fat removal exerts measurable, lasting metabolic benefits by way of changes to serum lipid profiles.

METHODS

PubMed, Cochrane CENTRAL, Embase, and clinical trials registers were searched using the Polyglot Search Translator to find studies examining quantitative changes in metabolic markers after nonsurgical body contouring procedures. The MethodologicAl STandard for Epidemiological Research (MASTER) scale was adopted for the quality assessment of the included studies. The robust-error meta-regression (REMR) model was employed.

RESULTS

Twenty-two studies and 676 participants were included. Peak body compositions measures manifest as a reduction of 2 units in body mass index (BMI), 1 kg of body weight (BW), 5 cm in waist circumference (WC) and 1.5 cm in abdominal fat thickness (FT), sustained up to 60 days postprocedure. Transient increases of 15 mg/dL in low-density lipoprotein (LDL), 10 mg/dl in triglycerides (TG), and 15 mg/dl in total cholesterol (TC) were observed at 2 weeks postprocedure.

CONCLUSION

While nonsurgical fat removal exerts sustained effects on body anthropometrics, changes to serum lipid profiles were transient. There is no compelling evidence at present to support the conclusion that nonsurgical fat removal is metabolically beneficial.

Numerical study of high-intensity focused ultrasound (HIFU) in fat reduction

INTRODUCTION

This study aimed to investigate the effect of fat-layer thickness and focal depth on the pressure and temperature distribution of tissue.

METHODS

Computer simulations were performed for the skin-fat layer models during high-intensity focused ultrasound (HIFU) treatment. The acoustic pressure field was calculated using the nonlinear Westervelt equation and coupled with the Pennes bioheat transfer equation to obtain the temperature distribution. To investigate the effect of the thickness of the fat layer on pressure and thermal distributions, the thickness of the fat layer behind the focal point (z = 13.5 mm) changed from 8 to 24 mm by 2 mm step. The pressure and temperature distribution spectra were extracted.

RESULTS

The simulated results were validated using the experimental results with a 98% correlation coefficient (p < 0.05). There was a significant difference between the pressure amplitude and temperature distribution for the 8-14 mm thickness of the fat layer (p < 0.05). By changing the focal point from 11.5 to 13.5 mm, the maximum acoustic pressure at the focal point increased 66%, and the maximum temperature was 56%, respectively.

CONCLUSION

Considering the specific treatment plan for each patient, according to the skin and fat layer thicknesses, can help prevent side effects and optimize the treatment process of HIFU.

Tissue specific considerations in implementing high intensity focussed ultrasound under magnetic resonance imaging guidance

High-intensity focused ultrasound can ablate a target permanently, leaving tissues through which it passes thermally unaffected. When delivered under magnetic resonance (MR) imaging guidance, the change in tissue relaxivity on heating is used to monitor the temperatures achieved. Different tissue types in the pre-focal beam path result in energy loss defined by their individual attenuation coefficients. Furthermore, at interfaces with different acoustic impedances the beam will be both reflected and refracted, changing the position of the focus. For complex interfaces this effect is exacerbated. Moreover, blood vessels proximal to the focal region can dissipate heat, altering the expected region of damage. In the target volume, the temperature distribution depends on the thermal conductivity (or diffusivity) of the tissue and its heat capacity. These are different for vascular tissues, water and fat containing tissues and bone. Therefore, documenting the characteristics of the pre-focal and target tissues is critical for effective delivery of HIFU. MR imaging provides excellent anatomic detail and characterization of soft tissue components. It is an ideal modality for real-time planning and monitoring of HIFU ablation, and provides non-invasive temperature maps. Clinical applications involve soft-tissue (abdomino-pelvic applications) or bone (brain applications) pre-focally and at the target (soft-tissue tumors and bone metastases respectively). This article addresses the technical difficulties of delivering HIFU effectively when vascular tissues, densely cellular tissues, fat or bone are traversed pre-focally, and the clinical applications that target these tissues. The strengths and limitations of MR techniques used for monitoring ablation in these tissues are also discussed.

Radiofrequency Heating and High-Intensity Focused Electromagnetic Treatment Delivered Simultaneously: The First Sham-Controlled Randomized Trial

Background:

Radiofrequency-based and high-intensity focused electromagnetic (HIFEM)-based devices have proved effective and safe for abdominal body shaping. Radiofrequency is known to reduce adipose tissue, whereas HIFEM treatment is effective for muscle definition. The authors investigated the efficacy of a novel device delivering synchronized radiofrequency and HIFEM treatment simultaneously for abdominal toning and fat reduction.

Methods:

Seventy-two patients were enrolled and randomly divided into active (n = 48; age, 45.5 ± 13.0 years) and sham groups (n = 24; age, 44.6 ± 12.3 years). Both groups received three treatments on the abdomen once a week. The intensity in the active group was set to maximum tolerable level; in the sham group, the intensities were set to 5 percent. Ultrasound images were taken before treatment and at 1, 3, and 6 months after treatment to examine changes in subcutaneous fat and rectus abdominis muscle thickness. Digital photographs were taken, and satisfaction and therapy comfort were assessed.

Results:

Ultrasound images of the active group at 1 month showed significant (p < 0.05) reduction in adipose tissue thickness by 20.5 percent (4.8 ± 2.6 mm), whereas rectus abdominis muscle thickness increased by 21.5 percent (2.0 ± 0.8 mm). Results at 3 months improved to 28.3 percent (7.6 ± 3.7 mm) and 24.2 percent (2.3 ± 0.9 mm), respectively. Improvements were maintained at 6 months after treatment in the active group, whereas the sham group showed no significant changes. Treatments were found to be comfortable. The active group showed higher satisfaction with outcomes.

Conclusion:

Active treatment utilizing simultaneous application of radiofrequency and HIFEM therapy resulted in a significant increase in rectus abdominis thickness and subcutaneous fat reduction, exceeding previously published results for separate HIFEM and radiofrequency treatments.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, II.

Evidence-Based Efficacy of High-Intensity Focused Ultrasound (HIFU) in Aesthetic Body Contouring

Being profitable procedures with little disposable costs, a number of noninvasive technologies have gained much popularity in recent years and are permeating the aesthetic marketplace. High-intensity focused ultrasound (HIFU) when focused at a targeted depth of 1.1 to 1.6 cm within subcutaneous tissue raises local tissue temperature at the focal point resulting in almost immediate cell death without damage to the surrounding tissues. Despite having gained popularity, little information is available regarding HIFU use for the treatment of localized fat and aesthetic body sculpturing. The current literature review is intended to investigate evidence-based efficacy of HIFU in aesthetic body contouring. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A self-assembled carrier-free nanosonosensitizer for photoacoustic imaging-guided synergistic chemo-sonodynamic cancer therapy

As one of the most promising noninvasive therapeutic modalities, sonodynamic therapy (SDT) can focus the ultrasound energy on tumor sites located in deep tissue and locally activate the preloaded sonosensitizer to kill tumor cells. However, exploring sonosensitizers with high SDT efficacy and desirable biosafety is still a significant challenge. Herein, we utilized the hydrophilic-hydrophobic self-assembly technology to assemble the hydrophobic organic dye Ce6 and broad spectral anti-cancer agent Paclitaxel with hydrophilic organic dye IR783 to generate a nanoscale sonosensitizer, Ce6-PTX@IR783, without the introduction of extra nanomaterials into the fabrication to guarantee high therapeutic biosafety and further potential clinical translation. The constructed nanodrug was endowed with an external ultrasound-activatable chemo-sonodynamic effect and photoacoustic imaging performance via integrating multiple moieties into one nanosystem. Ce6 could enhance the sonodynamic effect, while PTX exerted a chemotherapeutic effect, and IR783 was applied to increase tumor-specific accumulation and assist in fulfilling photoacoustic imaging. In particular, the small particle size (70 nm) of Ce6-PTX@IR783 contributed to the increased tumor accumulation via the enhanced permeability and retention effect. The high synergistically chemo-sonodynamic therapeutic efficacy has been successfully demonstrated in vitro and in vivo, in addition to the demonstrated high biodegradability, biocompatibility and biosafety. This facile self-assembly procedure provides an intriguing strategy for highly efficient utilization of hydrophobic drugs and is liable to realize large-scale production and further clinical translation.