Ultrasound and Histologic Examination after Subcutaneous Injection of Two Volumizing Hyaluronic Acid Fillers: A Preliminary Study

Current Practices in Hyaluronic Acid Dermal Filler Treatment in Asia Pacific and Practical Approaches to Achieving Safe and Natural-Looking Results

Complications such as delayed inflammatory reactions (DIRs) and unnatural outcomes can sometimes arise from hyaluronic acid (HA) dermal filler treatments and can be challenging to address. Given the popularity of HA dermal fillers for aesthetic procedures, there is a need for preventive strategies to minimize these complications. Two hundred practitioners from 10 regions in Asia Pacific who administer HA fillers completed a survey on prevention of DIRs and unnatural outcomes. Thirteen global experts convened to evaluate the current practices and propose practical approaches for safe and appropriate use of HA dermal fillers. From the survey, the top three measures used to reduce the risk of DIRs included choosing an appropriate HA filler, aseptic technique, and patient selection. Key strategies employed to achieve natural-looking outcomes were treatment customization, understanding the rheological properties and behavior of different HA fillers, and being conservative in treatment approach. The panel developed a concise reference guide aimed at minimizing the risk of DIRs while achieving natural aesthetic outcomes. Five practical considerations were recommended: patient assessment and individualization of treatment plan, choice of an appropriate HA filler, adequate knowledge of facial anatomy, strict adherence to aseptic methods, and proper injection technique. The panel highlighted the need for education efforts to increase awareness of differential immunogenicity between HA fillers and to improve understanding on the importance of preserving aesthetic individuality for optimal results. These practical insights from the global experts support practitioners in optimizing safety and quality of aesthetic treatment with HA fillers.

Materials Selection for the Injection into Vaginal Wall for Treatment of Vaginal Atrophy

Vaginal atrophy caused by the aging process and perineal trauma has a negative impact on women. A new vaginal atrophy treatment is injection of materials into the vaginal wall, including platelet-rich plasma (PRP), autogenous fat graft (AFG), hyaluronic acid (HA), botulinum toxin (BTX), and collagen, but to date their efficacy has not been reviewed. Vaginal wall injection is available only for mild cases of vaginal atrophy or as an adjunct to vaginal surgery. PRP is used mainly to restore vaginal function, and multiple injections are needed to achieve good results in vaginal atrophy. HA, AFG, and collagen are used mainly to augment the vaginal wall. BTX injection can inhibit vaginal muscle spasm and reduce pain during sexual intercourse in patients with vaginismus. Injection of most of these materials into vaginal wall is effective and relatively safe. Vascular embolisms are the most serious complication of vaginal injection and should be prevented. In addition, there has been no randomized double-blind placebo-controlled trial or discussion of methods to avoid serious complications resulting from vaginal injection. Therefore, further studies of the injection of materials into the vaginal wall to treat vaginal atrophy are required, and the procedures should be standardized to benefit more patients.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 .

Histological and Quantitative Appraisal of the Intradermal and Subcutaneous Distribution of the Hyaluronic Acid Injected into the Nasolabial Fold

BACKGROUND

Histological analysis of hyaluronic acid (HA) applied in the nasolabial fold (NLF) studied gel distribution into the dermis and subcutaneous fat, correlating density of NLF tissues, with cohesivity, concentration and degradation of HA.

METHOD

Ten patients received two injection points on each NLF. They were intradermal near the nasal ala and subcutaneous near the oral commissure. Injection points received 0.1 ml of 24 mg/ml HA cross-linked by BDDE 2.0 ppm through a bolus technique injection without retrograde backflow. Biopsies were taken 72 h and 9 months after application to histological analysis.

RESULTS

Dermis density fragmented the gel into small nodules, spreading it into the reticular dermis. Seventy-two hours after application, average diameter of the small nodules was 0.30 mm and at month nine 0.05 mm. Softness of the subcutaneous fat and high concentration of HA created a single and compact nodule. Seventy-two hours after application, average of nodule diameters was 1.05 mm and at month nine 0.49 mm. HA biodegradation occurred on the external surface of the gel. The single nodule offered small contact surface to enzymes, slowing gel degradation. The sum average of the diameters of the small nodules offered a large contact surface to enzymes, accelerating gel degradation.

CONCLUSION

Permanence of the HA into the tissues depended on the relationship between the gel distribution and its degradation. Due to the small contact surface of the single nodule to enzymes, permanence of the HA into the subcutaneous fat was more extended than into the dermis.

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 .

Histological and Clinical Appraisal of Distribution and Long Acting New Hyaluronic Acid into the Subcutaneous Fat of the Forehead to Improve Horizontal Lines

BACKGROUND

A new hyaluronic acid (HA) was appraised to improve forehead horizontal lines (FHL). Histological analysis correlated the gel distribution with clinical findings and also with wrinkle depth, 48 h and 12 months after HA application.

METHODS

The new filler composed by 24 mg/ml of HA cross-linked with BDDE 2.0 ppm was injected into the subcutaneous fat, just beneath the dermis, through a retrograde backflow injection technique applied in sequence. Biopsies were taken with a 3.0-mm-diameter skin punch before HA application, 48 h and 12 months after HA application for histological evaluation.

RESULTS

Subcutaneous application created a compact cylindrical filament as pattern of gel distribution, which acted as strut raising the FHL to the level of the surrounding tissues. Diameter average of the filament 48 h after HA application was 1.18 mm and at month twelve 0.34 mm. The residual amount of the gel at month twelve ensured the long acting of the HA into the subcutaneous fat. FHL depth of 251.83 µm before HA application and 190.20 µm after 12 months indicated that the residual amount of gel at month twelve still projected FHL.

CONCLUSION

High cohesivity of HA and low density of forehead subcutaneous fat caused the gel to take the form of a compact cylindrical filament. The small amount of gel still presenting into the subcutaneous fat 12 months after application validated the long acting of the HA. Evidence-based analysis showed that this new filler might be considered a safe alternative for improvement in the FHL.

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 .

Spreading Pattern and Tissue Response to Hyaluronic Acid Gel Injections in the Subcutis: Ultrasound Videos, Ultrasound Measurements, and Histology

Background

Despite the popularity of hyaluronic acid (HA) filler treatments, few publications focus on their effects on adipose tissue.

Objectives

The authors assessed the deposition pattern in the subcutis of injected HA, the tissue response at short and intermediate term, and the effects of remodeling the filler by strong finger pressure immediately after the treatment.

Methods

Two brands, specifically developed by the industry for deep injection, were compared. The gels were injected subcutaneously in 5 candidates for abdominoplasty or breast reduction, in the area of excision, 6 to 98 days before surgery. Ultrasound measurements and films were compared with postoperative histological findings. Tissue response was scored semi-quantitatively.

Results

Real-time ultrasound showed a slightly different deposition pattern of the 2 brands. Histologically, both were present in large pools of the same magnitude and looked the same. Linear retrograde injection sometimes resulted in a globular deposit due to elastic recoil of septae. After remodeling and over time, HA deposits became difficult to detect by ultrasound. Firm remodeling of the tissue immediately after injection or time had no significant effect on filler spread or tissue response. Except for 1 zone of granuloma formation, tolerance for both fillers was good.

Conclusions

HA deposition in adipose tissue occurs in much larger pools than in the dermis. Ultrasound examination is useful during and immediately after the injection but less reliable after filler remodeling or over time. Filler deposition can be less precise, and reshaping by finger pressure can have less effect than expected.

Level of Evidence: 4

Ultrasound detection of cosmic filler injection of lips in camel beauty pageants: first report in veterinary medicine

This study was carried out in Saudi Arabia during the events of the 4th King Abdulaziz Camel Festival, Saudi Arabia. It was designed to describe the most frequent locations of injected cosmetic fillers in the head region as well as the ultrasound features of the injected material. Apparently healthy camels (Camelus dromedarius) (n = 11,626) were thoroughly examined for injection of cosmetic fillers in the head region. In parallel, 30 non-injected camels were used as controls. The lips of camels suspected of having been injected with fillers were subjected to high-resolution ultrasound examination. Of the 11,626 camels, 58 were found to have been injected with cosmetic fillers, 45 in the upper lip and 13 in both the upper and lower lip. None of the injected camels had a history of recent illness. In addition, in all the injected camels, no dermal lip lesions were seen by the naked eye. Swelling of the upper and/or lower lips was visually inspected and palpated by hand in 52 of the camels. Drooping and swinging of the injected lips were observed in all injected camels. Hardness was detected in the tip of the upper lips of 26 of the injected camels and multiple hard nodules were palpated in the injected lips of 44 camels. Swelling of the edges of the upper and lower lips was detected in 41 of the injected camels. Ultrasonographic features of the injected lips are described in detail. Blood samples were collected from both groups. In none of the injected camels did the hemato-biochemical profiles differ significantly than the control group. In conclusion, results clearly indicate the usefulness and convenience of ultrasound as a diagnostic tool to locate the presence of injected fillers and to help monitor the extension and complications of the deposits.

Herpes Zoster as a Differential Diagnosis for Ischemia after Facial Hyaluronic Acid Filler

The use of hyaluronic acid (HA) fillers for facial rejuvenation has grown widely and is now one of the most performed noninvasive cosmetic procedures. Viral infections can occur, albeit rarely. This report describes a 65-year-old female patient with significant fat tissue loss in the malar region who developed herpes zoster after receiving HA filler for facial volumization. We performed volumization with a total of 2mL of HA in one session. Two days after the procedure, the patient began feeling mild pain in the malar region bilaterally and in the right side of the nasolabial fold. Upon physical examination, vesicles and erythema were observed. Due to the possibility of herpes zoster virus (HZV) infection, the patient was treated with valacyclovir. Ultrasonography with arterial and venous Doppler study revealed normal blood flow in the angular artery path and adequate positioning of the filler. After seven days of valacyclovir, the patient had complete resolution of the lesions. Herpes virus reactivation can be caused by direct axon damage by the needle, by tissue manipulation, and by inflammatory reaction. Herpes simplex virus (HSV) is the virus most commonly involved and its incidence does not exceed 1.45 percent of the complication cases, and HZV is even rarer. Reactivation of HZV might mimic tissue ischemia. Ultrasonography is a noninvasive, fast, and useful tool to evaluate vascular impairment and the positioning of the filler.

Real-world Experience with Volume Augmentation using Cohesive Polydensified Matrix Hyaluronic Acid Gel: A Retrospective Single-center Analysis of 110 Consecutive Patients with Medium- to Long-term Follow-up

Objective: Hyaluronic acid (HA) volumizer injection into subcutaneous and deep tissue layers is increasingly used for nonsurgical volume loss correction. Information on optimal techniques, safety, and medium- to long-term satisfaction is limited. This study evaluated cohesive polydensified matrix^® HA volumizer CPM-26 (Modélis^® Shape or Belotero^® Volume) across different indications. Design: This study was a retrospective chart review and included a patient questionnaire given at six months posttreatment and during long-term assessment (mean: 3.2 years). Setting: This study was conducted in a Belgian single-site plastic surgery practice. Participants: Consecutive patients (n=110, aged 19-74 years, 81% female) receiving single/ multiple injections with CPM-26 between 2010 and 2016 were included. Measurements: Procedural details and safety outcomes, patient estimates of satisfaction and adverse events, and Global Aesthetic Improvement Scale (GAIS) score were considered. Results: Participants received 601 injections over 189 sessions. The most common sites for volumizing injection were the lateral midface, deep prejowl sulcus, and anterior midface. In six participants, the injection site was the penis (8, 1.3%). Questionnaire data were provided by 81 patients. At six months, 94.9 percent (74/78) were satisfied with outcomes, while, at long-term assessment (mean: 3.2 years), 74.9 percent (54/73) were satisfied. Conclusion: Deep CPM-26 injection improved appearance and was reported as beneficial by two-thirds of patients at long-term assessment. Local adverse events were minor, transient, and infrequently required treatment.

The Expanding Role of Diagnostic Ultrasound in Plastic Surgery

Supplemental Digital Content is available in the text.

Background:

Ultrasound in plastic surgery is quickly finding new applications. Ultrasound surveillance may replace ineffective individual risk stratification and chemoprophylaxis for deep venous thromboses. Abdominal penetration can be a catastrophic complication of liposuction. Preoperative screening for fascial defects may reduce risk. Limiting buttock fat injections to the subcutaneous plane is critical for patient safety, but it is difficult to know one’s injection plane.

Methods:

The author’s use of diagnostic ultrasound was evaluated from May 2017 to May 2018. Ultrasound scans were used routinely to detect deep venous thromboses. Patients undergoing abdominal liposuction and/or abdominoplasty were scanned for possible hernias. Other common applications included the evaluation of breast implants, breast masses, and seroma management. The device was used in surgery in 3 patients to assess the plane of buttock fat injection.

Results:

One thousand ultrasound scans were performed during the 1-year study period. A distal deep venous thrombosis was detected in 2 patients. In both cases, the thrombosis resolved within 1 month, confirmed by follow-up ultrasound scans. A lateral (tangential) fat injection method was shown to safely deposit fat above the gluteus maximus fascia.

Conclusions:

Ultrasound scans are highly accurate, noninvasive, and well-tolerated by patients. Some of these applications are likely to improve patient safety. Early detection of deep venous thromboses is possible. Unnecessary anticoagulation may be avoided. Subclinical abdominal defects may be detected. Ultrasound may be used in the office to evaluate breast implants, masses, and seromas. In surgery, this device confirms the level of buttock fat injection.

A novel animal model for residence time evaluation of injectable hyaluronic acid-based fillers using high-frequency ultrasound-based approach

BACKGROUND

Hyaluronic acid (HA)-based devices are among the most popular filler agents for skin rejuvenation. One of the principal goals is the improvement in residence time of HA-based products, to increase their performance and reduce frequency of the treatment. So, understanding fillers, behavior after subcutaneous injection is a fundamental aspect for discovery and optimization of new products. Current in vivo approaches to detect/quantify injected HA fillers are not always well optimized or easy to apply.

OBJECTIVE

To develop more efficacious and noninvasive diagnostic tools to make a quantitative evaluation of the degradation of fillers in a small animal model.

MATERIALS AND METHODS

We evaluated the residence time of different HA-based fillers, fluorescein-labeled and not, injected subcutaneously in mice. Volumes of fillers were monitored through high-frequency ultrasound (HF-US) method while fluorescence intensity through the well-established fluorescence living imaging method. To confirm the effectiveness of HF-US, obtained volumetric measurements were compared with fluorescence intensity values.

RESULTS

Both the presented methods revealed the same degradation kinetics for the tested products.

CONCLUSION

The two used methods are fully comparable and quantitatively accurate. The presented approach has been proved to be noninvasive, sensitive, and reproducible.

Cohesive Polydensified Matrix® hyaluronic acid volumizer injected for cheek augmentation has additional positive effect on nasolabial folds

Purpose

Cohesive Polydensified Matrix^® hyaluronic acid (CPM-HA) volumizer has been used successfully for several years to reverse biometric volume loss during facial aging. This observational study explored the additive effect on nasolabial folds when CPM-HA volumizer is injected into the neighboring cheek area.

Patients and methods

In this open-label, prospective, postmarketing noninterventional study, 18 adult patients seeking esthetic enhancement of the lateral cheek hollows and cheekbone area were injected with CPM-HA volumizer integrated with lidocaine (CPM-HA-VL) in the upper or lower cheek area. Safety and performance of CPM-HA-VL up to 12 months after injection with follow-up visits at week 4 and month 3, 6, and 12 were assessed. The primary endpoint was improvement of cheek fullness on the validated Merz Aesthetics Scales. Additionally, changes in nasolabial folds were quantified using a phaseshift rapid in vivo measurement of skin optical three-dimensional (3D) in vivo measurement device.

Results

Patients (94.4% female, median age 52 years, age range 39–69 years) were injected with a mean volume of 2.5±1.1 mL CPM-HA-VL per side. Immediately after injection, mean severity for upper and lower cheek fullness assessed on the validated MAS improved from 2.5±0.6 and 2.8±0.5, respectively, to 1.0±0.0, and remained unchanged through month 12. Improvement in relation to baseline was attested on the Global Aesthetics Improvement Scale for all assessments. Compared with baseline, the following assessments offered a statistical significance in the reduction of wrinkle depth of nasolabial folds (maximum depth reduction by 30.4% at 3 months) according to optical 3D in vivo measurements. Pain during injection was minimal and abated within 30 minutes. Treatment was well tolerated and led to great patient satisfaction.

Conclusion

CPM-HA-VL injected into the upper and lower cheeks led to long-lasting satisfactory cosmetic results in cheek augmentation as well as in reducing depth of nasolabial folds adjacent to the injection site.