Ultrasound-assisted lipoplasty

A 16-Year Review of Clinical Practice Patterns in Liposuction Based on Continuous Certification by the American Board of Plastic Surgery

BACKGROUND

The American Board of Plastic Surgery has collected data on cosmetic surgery tracers as part of the Continuous Certification process since 2005. The current study was performed to analyze evolving trends in liposuction from the American Board of Plastic Surgery database.

METHODS

Tracer data from 2005 through 2021 were reviewed and grouped into an early cohort (EC) (2005-2014) and a recent cohort (RC) (2015-2021). Fisher exact tests and two-sample t tests were used to compare patient demographics, techniques, and complications.

RESULTS

A total of 2810 suction-assisted liposuction cases were included (1150 EC, 1660 RC). In-office procedures increased (36% EC versus 41% RC). The use of general anesthesia remained the same (63% EC versus 62% RC). The use of power-assisted liposuction increased (24% EC versus 40% RC) and use of ultrasound-assisted liposuction decreased (5% versus 2%). With respect to body areas treated, liposuction of the abdomen (64% EC versus 69% RC), flanks (60% EC versus 64% RC), and back (22% EC versus 34% RC) increased; treatments of thighs (36% EC versus 23% RC), and knees (8% EC versus 5% RC) decreased. Intraoperative position changes are more common (30% EC versus 37% RC), as is liposuction of multiple areas in one case (28% EC versus 36% RC). The volume of lipoaspirate also increased (1150 cc EC versus 1660 cc RC).

CONCLUSIONS

This study highlights evolving trends in liposuction over 16 years. Liposuction is becoming more common as an outpatient procedure performed concomitantly with other procedures. Despite multiple emerging technologies, the popularity of power-assisted liposuction is increasing. Although adverse events have not significantly increased with these changes, the authors stress careful preoperative evaluation of patients to identify factors that increase the risk of complications.

Concentrated ultrasound-processed fat (CUPF): More than a mechanically emulsified graft

INTRODUCTION

Autologous fat grafting is still an evolving technique. Researchers have attempted to increase the survival rate of grafts by concentrating adipose-derived stem cells (ASCs). In this study, we investigate a novel method that combines ultrasonic processing and centrifugation to generate small fat particles termed concentrated ultrasound-processed fat (CUPF) for grafting.

METHODS

The standard approach for obtaining CUPF is described. The properties of processed fat, including CUPF, microfat, centrifuged fat, and nanofat, were investigated using histological observation. Comparative analyses were conducted on the cell number, viability, and immunophenotypic profile of stromal vascular fraction cells (SVFs). Cultured ASCs were evaluated for cell proliferation and adipogenic, osteogenic, and chondrogenic potential. The processed fats were transplanted and evaluated using in vivo and histological studies.

RESULTS

Compared with microfat, centrifuged fat, and nanofat, CUPF had a condensed tissue content and higher concentration of viable cells in a small tissue structure and could smoothly pass through a 27-gauge cannula. In the CUPF group, SVFs were isolated in great numbers, with high viability and a high proportion of CD29- and CD105-positive cells. ASCs from the CUPF group exhibited high proliferation and multilineage differentiation potential. The grafts from the CUPF group were well preserved, and histological quantification revealed an increase in the abundance of Ki67- and CD31-positive cells in the tissue.

CONCLUSIONS

Our study established a new fat processing strategy that combines ultrasonic processing and centrifugation to harvest small particle grafts named CUPF. CUPF concentrated a large number of ASCs and has great potential for regenerative therapy.

A. A, Elsayed SH. Effect of focused ultrasound cavitation augmented with aerobic exercise on abdominal and intrahepatic fat in patients with non-alcoholic fatty liver disease: A randomized controlled trial

OBJECTIVES

The study aimed to examine the effect of focused ultrasound cavitation augmented with aerobic exercise on localized abdominal and intrahepatic fat in fatty liver patients.

METHODS

34 fatty liver patients aged 30-45 with a body mass index (BMI) of 30-40 kg/m2 were randomly assigned into two equally numbered groups. Group A received focused ultrasound cavitation and moderate aerobic exercise for three months, while Group B (control group) received moderate aerobic exercise only. Abdominal subcutaneous fat volume, visceral fat volume, liver-to-spleen ratio (L/S ratio), body weight, BMI, and waist circumference were measured both before and after the study period.

RESULTS

Both groups showed significant improvements in subcutaneous fat volume, visceral fat volume, body weight, BMI, and waist circumference relative to baseline where (P < 0.001), with a higher percentage in group A. L/S ratio only showed a significant improvement in group A. Between-group differences were noteworthy regarding L/S ratio and waist circumference where (P < 0.0001).

CONCLUSION

While substantial risky measures in non-alcoholic fatty liver disease have been modified by aerobic exercise, its combination with focused ultrasound cavitation causes more notable effects on the reduction of abdominal and intrahepatic fat, making it a superior option.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04161703.

Optical monitoring of adipose tissue destruction under encapsulated lipase action

Enzymatic destruction of adipose tissue has been achieved by encapsulation of lipase into the polymeric microcapsules. Adipose tissue destruction was delayed while lipase is encapsulated comparing with the direct lipase action as demonstrated by optical microscopy and optical coherence tomography in in vitro studies. Raman spectroscopy confirms that triglycerides in fat tissue were cleaved into free fatty acids, glycerol, and possible di- and monoglyceride residues. The results underpin the concept of local and controlled treatment of tissues via encapsulation. Effect of lipase encapsulation into the polymeric microcapsules on adipose tissue destruction compared to free lipase application.

Unfavourable outcomes of liposuction and their management

Liposuction is one of the most popular cosmetic surgery procedures currently performed by plastic surgeons around the world. It must be clear at the outset that liposuction is not primarily a modality for weight loss, it is meant to be a body contouring procedure and therefore the inherent limitations and safety issues related to this must always be respected if complications and unfavourable results are to be avoided as far as possible.

Bio-effects and safety of low-intensity, low-frequency ultrasonic exposure

Low-frequency (LF) ultrasound (20-100 kHz) has a diverse set of industrial and medical applications. In fact, high power industrial applications of ultrasound mainly occupy this frequency range. This range is also used for various therapeutic medical applications including sonophoresis (ultrasonic transdermal drug delivery), dentistry, eye surgery, body contouring, the breaking of kidney stones and eliminating blood clots. While emerging LF applications such as ultrasonic drug delivery continue to be developed and undergo translation for human use, significant gaps exist in the coverage of safety standards for this frequency range. Accordingly, the need to understand the biological effects of LF ultrasound is becoming more important. This paper presents a broad overview of bio-effects and safety of LF ultrasound as an aid to minimize and control the risk of these effects. Its particular focus is at low intensities where bio-effects are initially observed. To generate a clear perspective of hazards in LF exposure, the mechanisms of bio-effects and the main differences in action at low and high frequencies are investigated and a survey of harmful effects of LF ultrasound at low intensities is presented. Mechanical and thermal indices are widely used in high frequency diagnostic applications as a means of indicating safety of ultrasonic exposure. The direct application of these indices at low frequencies needs careful investigation. In this work, using numerical simulations based on the mathematical and physical rationale behind the indices at high frequencies, it is observed that while thermal index (TI) can be used directly in the LF range, mechanical index (MI) seems to become less reliable at lower frequencies. Accordingly, an improved formulation for the MI is proposed for frequencies below 500 kHz.

Characterizing bubble dynamics created by high-intensity focused ultrasound for the delivery of antibacterial nanoparticles into a dental hard tissue

Hig hintensity focused ultrasound (HIFU) has been applied for drug delivery in various disease conditions. Delivery of antibacterial-nanoparticles into dental hard tissues may open up new avenues in the treatment of dental infections. However, the basic mechanism of bubble dynamics, its characterization, and working parameters for effective delivery of nanoparticles, warrants further understanding. This study was conducted to highlight the basic concept of HIFU and the associated bubble dynamics for the delivery of nanoparticles. Characterization experiments to deliver micro-scale particles into simulated tubular channels, activity of ultrasonic bubbles, and pressure measurement inside the HIFU system were conducted. Subsequently, experiments were carried out to test the ability of HIFU to deliver nanoparticles into human dentine using field emission scanning electron micrographs (FESEM) and elemental dispersive X-ray analysis (EDX). The characterization experiments showed that the bubbles collapsing at the opening of tubular channels were able to propel particles along their whole length. The pressure measured showed sufficient negative and positive pressure suggesting that the bubble grew to a certain size before collapsing, thus enabling the particles to be pushed. The FESEM and EDX analysis highlighted the ability of HIFU to deliver nanoparticles deep within the dentinal tubules. This study highlighted the characteristics and the mechanism involved of the bubbles generated by the HIFU and their capability to deliver nanoparticles.

Safety of ultrasound-assisted liposuction: a survey of 660 operations

BACKGROUND

Ultrasound-assisted liposuction (UAL), although providing some advantages over tumescent liposuction (TL) and traditional or suction-assisted liposuction (SAL), has been found to have some controversial complications. We performed this study to evaluate UAL's complications and to compare UAL with the previous routine techniques for liposuction.

METHODS

Six hundred sixty UALs were performed on 609 consecutive volunteers by one cosmetic surgeon. Demographic characteristics, local and systemic complications, and also severe adverse events (SAE) were registered intraoperatively and at 1, 4, and 12 weeks postoperatively.

RESULTS

No SAEs were identified and only nine complications, consisting of two systemic complications (two cases of hypotension) and seven local complications (3 seromas, 3 cases of contact dermatitis, and 1 case of hemorrhage), were registered. This yields a complication incidence of 1.36%. There was no association between the number of complications and the body region, age, gender, or body mass index (BMI).

CONCLUSION

Our findings are in line with others in that performing UAL using local tumescent anesthesia is a safe procedure with a very low complication rate and has remarkable advantages over other liposuction techniques (TL and SAL). In addition, there was no correlation between the incidence of complications and body region, age, gender, or BMI.

ASERNIP-S: international trend setting

The Australian Safety and Efficacy Register of New Interventional Procedures--Surgical (ASERNIP-S) came into being 10 years ago to provide health technology assessments specifically tailored towards new surgical techniques and technologies. It was and remains the only organisation in the world to focus on this area of research. Most funding has been provided by the Australian Government Department of Health, and assessments have helped inform the introduction of new surgical techniques into Australia. ASERNIP-S is a project of the Royal Australasian College of Surgeons. The ASERNIP-S program employs a diverse range of methods including systematic reviews, technology overviews, assessments of new and emerging surgical technologies identified by horizon scanning, and audit. Support and guidance for the program is provided by Fellows of the Royal Australasian College of Surgeons. ASERNIP-S works closely with consumers to produce health technology assessments and audits, as well as consumer information to keep patients fully informed of research. Since its inception, the ASERNIP-S program has developed a strong international profile through the production of over 60 reports on evidence-based surgery, surgical technologies and audit. The work undertaken by ASERNIP-S has evolved from assessments of the safety and efficacy of procedures to include guidance on policies and surgical training programs. ASERNIP-S needs to secure funding so that it can continue to play an integral role in the improvement of quality of care both in Australia and internationally.

Principles of liposuction

There has been a dramatic increase in liposuction procedures during the last decade by both dermatologic and plastic surgeons. It is one of the most commonly performed cosmetic surgery procedures. Since its inception in 1976, numerous major advances have made the procedure more successful for both the surgeon and patient alike. This article reviews the current principles of liposuction and serves as a comprehensive overview of recent innovations in this field.

Numerical analysis of a gas bubble near bio-materials in an ultrasound field

Ultrasonic cavitation bubble phenomena play a key role in numerous medical procedures such as ultrasound-assisted lipoplasty, phacoemulsification, lithotripsy, brain tumor surgery, muscle and bone therapies and intraocular or transdermal drug delivery. This study investigates numerically the interaction of a bubble with a bio-material (fat, skin, cornea, brain, muscle, cartilage or bone) involved in the treatments mentioned when subjected to an ultrasound field. A range of frequencies is used to study the bubble behavior in terms of its growth and collapse shapes, and the maximum jet velocity attained. Simulation results show complex dynamic behaviors of the bubble. In several cases a jet is formed directed away from the bio-material while in others, toward it. In certain cases, the bubble eventually breaks into two, with or without the formation of opposite penetrating jets. Very high maximum velocities of jets directing away or toward the bio-materials can be observed in some cases (700 to 900 ms(-1)).

Use of Ultrasonography-Assisted Liposuction for the Treatment of Human Immunodeficiency Virus--Associated Enlargement of the Dorsocervical Fat Pad

Enlargement of the dorsocervical fat pad (i.e., "buffalo hump") is one manifestation of the lipodystrophy syndrome associated with human immunodeficiency virus. We report our experience with the use of ultrasonography-assisted liposuction in a cohort of 10 patients with this complication.