Thermal effects of percutaneous application of plasma/radiofrequency energy on porcine dermis and fibroseptal network

Enhanced Fat Graft Viability and Remodeling Using a Helium-based Radiofrequency Device to Prepare the Recipient Site

BACKGROUND

Improvements to autologous fat grafting for soft tissue augmentation are needed to overcome the unpredictable volume retention. Approaches such as fat harvesting and processing, injection technique, preparation of the recipient site, and supplemental biologics are topics of ongoing research. Here, an energy-based device was investigated as a stimulatory tool for recipient site preparation for improving fat graft retention.

OBJECTIVE

The objective was to measure the stimulatory responses in fat grafts after 4 weeks when using a helium-based radiofrequency device to pretreat the recipient tissue.

METHODS

Using an autologous fat grafting mouse model, the inguinal fat pad was grafted in a small cranial pocket after either a saline injection alone (control) or a saline injection followed by pretreatment (treated). The fat pad was resected after 4 weeks, sectioned and stained with immunofluorescence markers to investigate tissue remodeling.

RESULTS

Pretreatment resulted in higher viability of adipocytes, a higher concentration of viable ASCs in areas of adipose tissue regeneration, and localized macrophages in the areas of regeneration when compared to the control. There was no observable difference in vascularity or angiogenesis. The staining for ASCs was higher in the pretreated group in comparison with the control group (5.0% vs. 3.3%, p=0.36) when using a pixel classifier in QuPath in the viable adipose tissue regions.

CONCLUSIONS

The use of a helium-based radiofrequency device as a pretreatment tool appears to increase the viability of the adipose tissue likely due to higher concentration of ASCs. The apparent increase in viable ASCs may be due to enhanced proliferation or paracrine recruitment of these cells in response to the helium-based radiofrequency treatment.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 . Bullet List of Important Points: Pretreatment of the fat graft recipient site increases the viability of the adipose tissue after 4 weeks in comparison with the control grafts. The increased viability is likely due to the observed increase in adipose-derived stem cells in the pretreated group. Pretreatment enhanced the adipose tissue remodeling as colocalization of adipose-derived stem cells and macrophages showed an active remodeling, whereas the control group exhibited more necrotic and fibrotic tissue.

Lipoplasty in the Overweight Patient

The practice of large volume liposuction, when executed by board-certified plastic surgeons using a variety of energy-assisted liposuction devices, has been substantiated as a secure procedure, yielding enhanced aesthetic results and minimal complications. Techniques including the superwet technique and ultrasonic-assisted liposuction are utilized to diminish blood loss, while also maintaining a keen awareness of the maximum volume of infiltration fluid permissible for safe infusion. Adherence to evidence-based protocols is of paramount importance to reduce the risk of postoperative complications. These protocols encompass hypothermia prevention, deep vein thrombosis (DVT) prophylaxis, and perioperative antibiotic prophylaxis. To ensure the highest quality of care, it is recommended that large volume liposuction procedures be performed in accredited hospitals or certified ambulatory surgery centers. Postoperative procedures should include overnight admission of patients to facilitate proper hemodynamic monitoring. While the employment of multiple devices such as VASERLipo and Renuvion has been noted to augment skin and soft tissue contraction, it is worth noting that there may be a heightened risk of seroma formation (at 2.27%) and subcutaneous emphysema (at 1.47%). Consequently, prudent use of these advanced medical devices is essential to avoid any potential adverse events.

Update: Cellulite Therapies and Optimizing Treatment Combinations

Cellulite in the proximal lower extremities is a reported concern among many adult females. The unsightly appearance of cellulite leads many affected individuals to seek treatment by trained specialists. The objective of this review is to provide the reader with an update on new and innovative therapies for cellulite including various treatment combinations to maximize therapeutic outcomes, and strategies for minimizing adverse events. The availability of new technologies and the results from recent clinical trials provide additional tools and data to consider when creating treatment plans for cellulite patients. This update to previous treatment recommendations is based on the most recent developments in cellulite management including the personal experiences of the authors with an emphasis on injectable enzymes, acoustic subcision, targeted verifiable subcision, and biostimulators. Formal clinical studies are warranted to compare various treatment modalities and further investigate combination regimens.

LEVEL OF EVIDENCE: 5

Assessment of Laser Parameters to Improve Lid Tension-A Proof of Concept towards Lasercanthoplasty

BACKGROUND

Preliminary clinical work indicates that increasing eyelid tension improves the function of the meibomian glands. The aim of this study was to optimize laser parameters for a minimally invasive laser treatment to increase eyelid tension by coagulation of the lateral tarsal plate and canthus.

METHODS

Experiments were performed on a total of 24 porcine lower lids post mortem, with six lids in each group. Three groups were irradiated with an infrared B radiation laser. Laser-induced lower eyelid shortening was measured and the increase in eyelid tension was assessed with a force sensor. A histology was performed to evaluate coagulation size and laser-induced tissue damage.

RESULTS

In all three groups, a significant shortening of the eyelids after irradiation was noticed (p < 0.0001). The strongest effect was seen with 1940 nm/1 W/5 s, showing -15.1 ± 3.7% and -2.5 ± 0.6 mm lid shortening. The largest significant increase in eyelid tension was seen after placing the third coagulation.

CONCLUSION

Laser coagulation leads to lower eyelid shortening and an increase in lower eyelid tension. The strongest effect with the least tissue damage was shown for laser parameters of 1470 nm/2.5 W/2 s. In vivo studies of this effect have to confirm the efficacy of this concept prior to clinical application.

Adverse Events of Soft Tissue Coagulation Using a Helium-Based Plasma Technology Alone and in Combination With Ultrasound-Assisted Liposuction

Background

Protein denaturation and collagen contraction occur when living tissue is heated to well-defined temperatures. The result is reduced volume and surface area of the heated tissue.

Objectives

To evaluate the adverse events of procedures in which a helium-based plasma technology (HPT) was used with and without ultrasound-assisted liposuction for the coagulation of soft tissue.

Methods

A multicenter retrospective chart review was performed in which patients (n = 192) were divided into 2 groups: one that received only soft tissue coagulation and the other that received both soft tissue coagulation and liposuction. Each of the 2 groups was subdivided into patients with and without adverse events, including seroma. Odds ratios for adverse events were calculated for both demographic and surgical subgroups. Seroma data were analyzed separately.

Results

No serious adverse events were observed. Forty-six (24.0%) patients reported 51 total adverse events. Seroma was the most frequently occurring adverse event with 13 patients (6.8%) reporting 17 (33.3%) events in 12 body areas. In these cases, all areas were treated with both liposuction and soft tissue coagulation. Seroma was not observed in patients receiving soft tissue coagulation alone. Patients aged 61 to 76 years and males were more likely to experience seroma or other adverse event than younger patients or females, respectively.

Conclusions

The use of the HPT for soft tissue coagulation in combination with ultrasound for liposuction is associated with nonserious adverse events. The most frequently occurring adverse event, seroma, was not observed in patients treated with HPT alone.

Level of Evidence 3

Thermal effects of percutaneous application of plasma/radiofrequency energy on porcine dermis and fibroseptal network

Background

Skin laxity is one of the defining characteristics of aging and can be the result of various factors including intrinsic aging, genetics, diet, stress, lifestyle, sun exposure, weight fluctuations, and smoking. Recent reports suggest the ability of subdermal energy application to reduce skin laxity. Thermal energy can be delivered using different devices including lasers, radiofrequency (RF) monopolar and bipolar devices, and plasma/RF devices. Plasma‐based energy platforms generate a plasma gas, allowing heat to be applied to the tissue. This study focused on the evaluation of thermal effect of plasma/RF compared to a monopolar RF device applied percutaneously to the subdermis and connective fibroseptal network in a porcine model.

Methods

The subdermal application of energy was conducted using a plasma/RF system and a monopolar RF system. Both low and high energy/temperature settings were evaluated in dynamic and stationary modes. Histomorphometry was used to determine the depth of thermal effect associated with each treatment setting.

Results

Both dermis and fibroseptal network tissue exhibited the presence of microscopically thermally treated zones. There were no significant differences in average and maximum depths of thermal effect between the different handpieces and electrosurgical systems used for all treatment settings.

Conclusions

No significant differences in the thermal effect between plasma/RF and monopolar RF systems were observed, suggesting that plasma/RF systems can be safely used for the percutaneous application of energy in the subcutaneous space.