Understanding Platysma Muscle Contraction Pattern and Its Relationship to Platysmal Banding: A Real-Time Ultrasound Study.

BACKGROUND: Addressing neck contouring with surgical and nonsurgical aesthetic procedures includes understanding the origin of platysmal banding. A theory was postulated to explain this phenomenon by isometric vs isotonic muscular contraction patterns. However, no scientific proof had been provided to date for its correctness. OBJECTIVES: The aim of this study was to confirm the correctness of the platysmal banding theory based on isometric vs isotonic muscular contractions. METHODS: Eighty platysma muscles from 40 volunteers (15 males and 25 females) were investigated (mean age 41.8; SD 15.2 years; mean BMI of 22.2; SD 2.3 kg/m2). Real-time ultrasound imaging was utilized to measure the increase in local muscle thickness inside and outside of a platysmal band as well as platysma mobility. RESULTS: Within a platysmal band, the local thickness of the muscle increases during muscular contractions by 0.33 mm (37.9%; P < .001). Outside of a platysmal band the thickness of the platysma muscle decreased by 0.13 mm (20.3%; P < .001). It was identified that within a platysmal band no gliding was detectable, whereas outside of a band an average muscle gliding of 2.76 mm was observed. CONCLUSIONS: The results confirm the correctness of the isometric vs isotonic platysma muscle contraction pattern theory: isotonic muscle contraction (gliding without increase in tension and therefore in muscle thickness) vs isometric muscle contraction (no gliding but increase in tension and therefore in muscle thickness). These 2 types of contraction patterns occur within the platysma simultaneously and are an indicator for zones of adhesion in the neck to guide surgical and nonsurgical aesthetic procedures.

Safety considerations for treating the parotid and submandibular glands with neuromodulators for facial slimming.

BACKGROUND: Neuromodulators have predominantly been used for the treatment of upper facial lines, but their use has expanded to include lower face and neck treatments. However, the injection sites for these treatments are based on skin surface landmarks, which may pose risks to nearby structures and result in undesired outcomes. OBJECTIVE: To investigate the spatial relationship between the FDA-approved skin surface landmarks for neuromodulator injections in the parotid and submandibular glands and the topographical anatomy of critical facial structures such as the facial artery, facial vein, external carotid artery, and retromandibular vein. MATERIALS AND METHODS: A cross-sectional retrospective analysis was conducted on contrast-enhanced cranial CT scans. The scans were analyzed for the morphology and location of the parotid and submandibular glands. Measurements were taken for gland volume, craniocaudal extent, anterior-posterior extent, and distances between the skin surface and gland capsule or nearby structures such as arteries. RESULTS: The study sample consisted of 53 subjects, including 7 males and 46 females, with a mean age of 36.91 years and a mean BMI of 23.28 kg/m2 . The mean volume of the parotid gland was 31.9 ± 3.0 cc in males and 28.5 ± 3.6 cc in females with p < 0.001, while the mean volume of the submandibular gland was 18.2 ± 2.0 cc in males and 14.5 ± 3.4 cc in females with p < 0.001. The mean distances between skin surface and the gland capsule were 5.98 ± 2.2 and 8.84 ± 4.0 mm for the parotid and submandibular gland, respectively. This distance increased with higher age and higher BMI values in a statistically significant manner with p < 0.001. CONCLUSION: The distances between FDA-approved skin surface landmarks and the parotid and submandibular glands varied significantly depending on gender, age, and BMI. Optimal injection depth and location for neuromodulator treatments cannot be generalized based on these landmarks alone, emphasizing the need for real-time ultrasound imaging guidance.

How to improve infraorbital hollows with neuromodulators-A clinical prospective interventional study about the application of facial biomechanics.

BACKGROUND: A previous injection algorithm termed the "Toxin Lift" was recently introduced and described volume increases in the midface following neuromodulator treatments of the jawline. Increase in midfacial volume due to soft tissue repositioning could also affect the severity of infraorbital hollows. OBJECTIVE: The objective is therefore to evaluate whether the severity of infraorbital hollows can be improved by injecting neuromodulators in the supra-mandibular segment of the platysma. MATERIALS AND METHODS: A total of 35 volunteers (11 males/24 females) with a mean age of 39.8 (9.6) years and a mean BMI of 25.2 (5.2) kg/m2 were investigated. Bilateral infraorbital regions were evaluated via clinical assessment and semi-quantitative 3D imaging. The applied injection technique targeted the platysma via four injection points administering 5 I.U. per injection point resulting in a total of 20 I.U. per facial side. RESULTS: Volume increase of the infraorbital region was 0.13 cc at 15 days (p = 0.001) and was 0.02 cc at 30 days (p = 0.452) whereas the skin displacement in cranial direction was 0.54 mm at 15 days (p < 0.001) and was 0.31 mm at 30 days (p < 0.001). Clinical evaluation revealed a highly statistically significant improvement of the tear trough, palpaebromalar groove, and of the lid-cheek junction when compared to baseline with all p < 0.001. CONCLUSION: The results of this clinical prospective interventional analysis revealed that the "Toxin Lift" injection technique is capable to improve the clinical appearance of infraorbital hollows. The effects can be explained by the concepts of facial biomechanics.

A Computed Tomographic Investigation of the Ophthalmic Artery Volume and Its Relevance to Soft Tissue Filler Injections.

BACKGROUND: The measured intraarterial volume of cadaveric ophthalmic arteries was utilized for safety recommendations during facial soft tissue filler injections. However, its clinical practicability and model applicability have become questionable. OBJECTIVES: To measure the volume of the ophthalmic artery in living individuals by utilizing computed tomography (CT) imaging technology. METHODS: A total of 40 Chinese patients (23 males, 17 females) were included in this study with a mean age of 61.0 (14.2) years and a mean body mass index of 23.7 (3.3) kg/m2. Patients were investigated with CT imaging technology to evaluate the length, diameter, and volume of the bilateral ophthalmic arteries as well as the length of the bony orbits, resulting in a total of 80 investigated ophthalmic arteries and orbits. RESULTS: Independent of gender, the average length of the ophthalmic artery was 80.6 (18.7) mm, the calculated volume of the ophthalmic artery was 0.16 (0.05) mL and the minimal and maximal internal diameter of the ophthalmic artery were 0.50 (0.05) mm and 1.06 (0.1) mm, respectively. CONCLUSIONS: Based on the results obtained from the investigation of 80 ophthalmic arteries it must be concluded that current safety recommendations should be reevaluated. The volume of the ophthalmic artery appears to be 0.2 mL rather than 0.1 mL as previously reported. In addition, it appears impractical to limit the volume of soft tissue filler bolus injections to 0.1 mL due to the aesthetic requirements of each individual patient and treatment plan.

Multimodal Analyses of the Aging Forehead and Their Clinical Implications.

BACKGROUND: Recent research has indicated that in the upper face a delicate arrangement exists between the muscles of facial expression and the skin. This arrangement allows for immediate transmission of movements following muscle contraction, resulting in skin movements and skin rhytid formation. OBJECTIVES: To investigate age-related changes of the biomechanical unit formed by facial muscles, their connective tissue envelope, and the skin of the upper face. METHODS: A total of 76 Caucasian volunteers (30 males, 46 females) with a mean age of 42.2 years (SD 18.6) and a mean body mass index of 24.58 kg/m2 (SD 3.7) were investigated. Three upper facial regions were analyzed for skin firmness and elasticity with cutometric assessment, vertical and horizontal skin vector displacement using 3-dimensional imaging, and muscle activity with surface-derived electromyography. RESULTS: Study participants of older age (>42.2 years), when compared with younger participants (≤42.2 years), showed increased skin firmness, at 0.20 mm vs 0.30 mm (P < .001); decreased skin elasticity at 53.2% vs 69.0% (P < .001); increased vertical (not horizontal) skin mobility at 3.56 mm vs 1.35 mm (P < .001); and decreased surface-derived electromyography (sEMG) signal of the frontalis muscle with 174 µV vs 309 µV (P = .039). CONCLUSIONS: This study reveals that age-related changes occur in each component of the biomechanical unit formed by facial muscles, connective tissue envelope, and skin in the upper face. Knowledge and understanding of such changes can allow for more targeted and individualized surgical and nonsurgical aesthetic treatments.

3D Anthropometric Facial Imaging - A comparison of different 3D scanners.

Facial measurements serve as a valuable tool in the treatment planning of facial plastic surgery. The aim of this study was to evaluate the accuracy and reliability of standard 3D anthropometric measurements of the face made with one low-cost handheld 3D scanner and one industrial-type mobile 3D scanner. There are clear potential benefits of using 3D measurements by means of new handheld mobile scanners. However, the Sense scanner from the class of inexpensive scanners showed significant limitations in more complex areas such as the lip and nose, whereas proportions could be measured satisfactorily.

Facial Soft Tissue Repositioning With Neuromodulators: Lessons Learned From Facial Biomechanics.

BACKGROUND: Neuromodulators have proven efficacy in reducing facial rhytides and have also been reported to improve jawline contour and the appearance of platysmal bands. Lifting effects of the tail of the eyebrow are expected outcomes when targeting the lateral periorbital region, underscoring the versatility of neuromodulator treatments. OBJECTIVES: The aim of this study was to analyze the clinical effectiveness of a novel neuromodulator-based injection algorithm with regards to its ability to reposition the middle and lower facial soft tissues. METHODS: Seventy-five study participants (8 males, 67 females) with a mean [standard deviation] age of 37.5 [8.5] years were injected with neuromodulators in the subdermal plane of the mandibular soft tissues following a standardized algorithm. Live rating of clinical appearance was performed, as well as volume change and skin vector displacement measured by 3-dimensional imaging at baseline, Day 14, and Day 30. RESULTS: Three-dimensional volume analysis revealed an increase in midfacial volume by 0.46 mL, and a decrease of the lower facial volume by 0.30 mL compared with baseline. Additionally, an improvement of midfacial fullness (by 0.13) and jawline contour (by 0.44) was reported on clinical rating scales at Day 30 compared with baseline. CONCLUSIONS: Facial soft tissues can be repositioned during the 30-day follow-up period following a neuromodulator treatment; this was reflected through an increase in midfacial volume as well as through a decrease in lower facial volume. The novel injection algorithm presented can provide a safe and effective option for patients desiring improvement of midfacial fullness and jawline contour with neuromodulator treatment alone.

The Difference in Facial Movement Between the Medial and the Lateral Midface: A 3-Dimensional Skin Surface Vector Analysis.

BACKGROUND: Our understanding of the functional anatomy of the face is constantly improving. To date, it is unclear whether the anatomic location of the line of ligaments has any functional importance during normal facial movements such as smiling. OBJECTIVES: The authors sought to identify differences in facial movements between the medial and lateral midface by means of skin vector displacement analyses derived from 3-dimensional (3D) imaging and to further ascertain whether the line of ligaments has both a structural and functional significance in these movements. METHODS: The study sample consisted of 21 healthy volunteers (9 females and 12 males) of Caucasian ethnic background with a mean age of 30.6 (8.3) years and mean BMI of 22.57 (2.5) kg/m2. 3D images of the volunteers' faces in repose and during smiling (Duchenne type) were taken. 3D imaging-based skin vector displacement analyses were conducted. RESULTS: The mean horizontal skin displacement was 0.08 (2.0) mm in the medial midface (lateral movement) and was -0.08 (1.96) mm in the lateral midface (medial movement) (P = 0.711). The mean vertical skin displacement (cranial movement of skin toward the forehead/temple) was 6.68 (2.4) mm in the medial midface, whereas it was 5.20 (2.07) mm in the lateral midface (P = 0.003). CONCLUSIONS: The results of this study provide objective evidence for an antagonistic skin movement between the medial and lateral midface. The functional boundary identified by 3D imaging corresponds to the anatomic location of the line of ligaments.

The Layered Anatomy of the Nose: An Ultrasound-Based Investigation.

BACKGROUND: An increasing number of soft tissue filler procedures in the nasal region has been reported. Concomitant with demand, the number of complications has risen due to the difficulty in administering filler in a region where soft tissue layering is complex. OBJECTIVES: The authors sought to describe the layered soft tissue arrangement of the nose as it relates to the underlying arterial vasculature and to define safer zones for nasal filler enhancement. METHODS: A total of 60 (28 males and 32 females) study participants were investigated with respect to their layered anatomy in the midline of the nose utilizing ultrasound imaging. The presence and extent of the layered arrangement was examined as well as the depth of the arterial vasculature. RESULTS: In the mid-nasal dorsum, a 5-layer arrangement was observed in 100% (n = 60) of all investigated cases, whereas it was found to be absent in the nasal radix and tip. The 5-layer arrangement showed an average extent of 26.7% to 67.5% in relation to nasal length. The nasal arteries coursed superficially in 91.7% of all cases in the nasal radix, in 80% in the mid-nasal dorsum, and in 98.3% in the nasal tip. CONCLUSIONS: Soft tissue filler administration in the nose carries the highest risk for irreversible vision loss compared with any other facial region. The safety of soft tissue filler rhinoplasty procedures is enhanced by knowledge of the layered anatomy of the nose, the location and depth of the major nasal vasculature, and employment of maneuvers to decrease the risk of blindness.

Deformation of Needle Tips During Facial Soft Tissue Filler Injections: An Electron-Microscopic Study.

BACKGROUND: Injectable soft tissue fillers are used on a global scale for a variety of aesthetic indications. Despite their widespread use, there is a dearth of information regarding needle deformation following injection procedures. Repeated injections with the same needle could lead to progressive needle tip deformation, potentially resulting in decreased precision and increased patient discomfort. OBJECTIVES: The objective of this study was to quantify the magnitude of needle tip deformation utilizing scanning electron microscopy (SEM) image analysis. METHODS: An observational study was performed evaluating 4 differently sized needles following soft tissue filler injections for 5 different aesthetic indications (zygomatic arch, infraorbital, midcheek, nasolabial sulcus, and perioral) in patients aged 36 to 64 years. Following treatment, each needle was visualized and imaged through SEM, and the percentage of deformation in relation to the total amount of needle tip surface was calculated. RESULTS: The factor most influencing needle tip damage was revealed to be the number of injection passes, ie, dermal transitions. Per injection procedure, an increase in needle tip damage of 4.7% occurred. Touching the bone deformed the needle tip by 9.6% and an increase in needle size resulted in 0.13% more damage. CONCLUSIONS: To the authors' knowledge, this is the first SEM investigation to provide objective evidence for the deformation of needle tips after repeated facial soft tissue filler injections. These data may help improve patient safety and comfort during these minimally invasive procedures.

Influence of Rheological Properties and Needle Size on Extrusion Forces of Hyaluronic Acid Based Soft Tissue Fillers.

BACKGROUND: To date no precise data are available for extrusion forces related to the G-prime and G-double-prime of fillers in combination with different 27G and 30G needles. Therefore, the objective of this study was to analyze extrusion forces of various product-needle-combinations containing two different 27G and two different 30G needles in combination with fillers of a wide range of elastic moduli starting from 2.0 – 166.0 Pa. MATERIAL AND METHODS: Four different fillers with the following elastic moduli 1.87, 11.65, 61.80, 165.50 Pa were combined with four different needles: 27G ½”, internal diameter: 0.300 μm; 27G ½”, internal diameter: 0.241 μm; 30G ½”, internal diameter: 0.241 μm and 30G ½“, internal diameter: 0.240 μm. Product-needle-combination were subjected to uni-axial mechanical testing and the respective extrusion force was measured. RESULTS: The results of this study revealed that the G-prime and the G-double-prime of a product are statistically significantly related to their extrusion force, with higher G-prime/G-double-prime products requiring higher extrusion forces. The results additionally revealed that whether the size of the needle was described as 27G or 30G by the respective manufacturer statistically significant differences between the measured extrusion forces were detected. CONCLUSION: Injectors need to be aware that not every 27G/30G needle has the same extrusion force even though the external diameter is similar (27G or 30G); this might additionally influence the ability to withdraw blood during a pre-injection aspiration manoeuvre. J Drugs Dermatol. 20(5): doi:10.36849/JDD.5237.

To click or not to click - The importance of understanding the layers of the forehead when injecting neuromodulators - A clinical, prospective, interventional, split-face study.

BACKGROUND: Differences in the effectiveness of neuromodulator treatments for horizontal forehead lines dependent on depth of product administration have been described. However, knowledge in respect to the fascial anatomy of the forehead still remains elusive. AIMS: To relate the fascial anatomy of the forehead to the effectiveness of neuromodulator treatments by conducting a clinical, prospective, interventional split-face study in which injections for the treatment of horizontal forehead lines are performed differently between facial sides. METHODS: This study included a total of n = 14 patients with a mean age of 35.71 (7.8) years and mean body mass index of 21.9 (3.0) kg/m2 . One side of the forehead was injected superficially by positioning the product in the superficial fatty layer, whereas the contralateral side was injected deep targeting the supraperiosteal plane (random selection). The treatment outcome was rated by the physician and by two independent observers according to a forehead line severity scale (0-4) at 14 and at 30 days. RESULTS: All three observers agreed in their ratings (ICC: 0.942) that the deep injection technique resulted in a superior outcome: D14 (superficial vs deep) 0.17 (0.4) vs 0.14 (0.4; P = .583) at rest and 1.26 (0.6) vs 0.43 (0.5; P < .001) for frontalis contraction; D30 0.17 (0.4) vs 0.14 (0.3) at rest (P = .583) and 1.21 (0.6) vs 0.43 (0.5; P < .001) for frontalis contraction. CONCLUSION: The results of this study underscore how detailed anatomic knowledge can enhance results of aesthetic interventions, in this case horizontal forehead line treatment with neuromodulators.

Full-face effects of temporal volumizing and temporal lifting techniques.

BACKGROUND: Most injection techniques utilizing hyaluronic acid-based soft tissue fillers have predictable outcomes at the location injected. However, the temporal region has been identified to have aesthetic effects beyond the temple. AIMS: To identify and quantify the panfacial aesthetic effects of three different temporal injection techniques. PATIENTS/METHODS: The medical records of nine female and five male Caucasian patients with a mean age of 50.9 ± 11.9 years were retrospectively reviewed for the effects of these techniques: supraperiosteal, interfascial, and subdermal. Panfacial effects were evaluated by the semiquantitative assessment of aesthetic scores for the temple volume, the temporal crest visibility, the lateral orbital rim visibility, the position of the eyebrows, the severity of lateral canthal lines, the midfacial volume, and the contour of the jawline. RESULTS: The supraperiosteal injection technique had the greatest influence on improving the temporal volume (25.0%), the temporal crest (33.3%), and the lateral orbital rim visibility (31.0%) scales but had no effects in other facial regions. The interfascial injection technique revealed good effects on improving temporal hollowing (23.3%) but had an even greater effect on the crow's feet (26.8%) and on the position of the eyebrow (33.3%). The subdermal injection technique had its greatest effects in the lower face by improving the contour of the jawline (26.8%) followed by the improvement of the lower cheek fullness scale (14.3%). CONCLUSION: Future injection algorithms could utilize all three injection techniques together as one multi-layer injection approach with a tailored proportion of each technique based on the aesthetic needs of the patient.

Clinical validation of the temporal lifting technique using soft tissue fillers.

BACKGROUND: While the temporal lifting technique has gained increasing attention, there is a dearth of objective and reliable evidence of its effects. AIM: The objective of the present study is to analyze the ability of the temporal lifting technique to reduce the midfacial volume by soft tissue repositioning and to achieve an improved pan-facial appearance by targeting exclusively the subdermal plane of the posterior and superior temple with soft tissue fillers. METHODS: A total of 12 patients (1 male and 11 females) with a mean age of 36.75 ± 6.6 years and a mean body mass index of 23.04 ± 1.3 kg/m2 were included in this prospective clinical single-center interventional study. Injection-related outcome was evaluated utilizing 3D skin vector displacement and surface volume analyses and scoring based on five different evaluators. RESULTS: Three months after the treatment, the global esthetic improvement scale rating showed an improved outcome (3.08) when evaluated by the independent observers, very improved outcome when evaluated by the treating physician (4.33), and exceptional improvement when rated by the patient (4.83). Temporal volume improved by 0.36 (P < .001), lower cheek fullness by 0.47 (P < .001), and jawline contouring by 0.51 (P < .001). No major adverse events were reported during the 3-month observational period. CONCLUSION: Objective outcome measures have provided evidence that by augmenting the posterior superior temple the volume of the middle face can be reduced and the contour of the jawline can be accentuated; this is due to the underlying fascial anatomy and the resulting soft tissue re-position.

The Influence of the Insertion Angle on Middle and Lower Face Tissue-Mechanics When Treating the Nasolabial Folds with Facial Suspension Threads-An Experimental Split-Face Cadaveric Study.

A novel treatment approach to address the nasolabial fold is the insertion facial suspension threads. However, there is a paucity of data available to guide insertion techniques and material selection. Three female and two male cephalic specimens of Caucasian ethnicity (73.6 ± 6.5 years; 21.41 ± 2.2 kg/m2) were included into this experimental split-face study. One facial side was treated with polycaprolactone (PCL) thread: 180 mm, bidirectional, 18G 100 mm cannula, 20 degrees trajectory, preauricular approach whereas the contralateral side was treated with polydioxanone (PDO) thread: 100 mm, bidirectional, 19G, 60 mm cannula, 50 degrees trajectory, infraorbital approach. Three-dimensional imaging outcome measures included vertical and horizontal skin displacement and volume changes at the nasolabial sulcus, at the labiomandibular sulcus, and along the jawline. Comparing PCL 180 mm 20 degrees to PDO 100 mm 50 degrees: vertical lifting effect 1.42 ± 2.63 mm versus 1.24 ± 1.88 mm (p = 0.906); horizontal lifting effect 3.42 ± 1.44 mm versus -2.02 ± 1.84 mm (p = 0.001); nasolabial volume change -0.80 ± 0.65 mL versus -0.52 ± 0.17 mL (p = 0.367); labiomandibular volume change -0.45 ± 0.42 mL versus -0.16 ± 0.16 mL (p = 0.191); jawline volume change 0.02 ± 0.43 mL versus -0.01 ± 0.21 mL (p = 0.892). The study provides objective evidence for the short-term effectiveness of facial suspension threads in treating the nasolabial folds. The results point toward a better aesthetic outcome when utilizing long facial suspension threads that can effect full-face changes as compared with short facial suspension threads.

The Bidirectional Movement of the Frontalis Muscle: Introducing the Line of Convergence and Its Potential Clinical Relevance.

BACKGROUND: Cosmetic treatment of the forehead using neuromodulators is challenging. To avoid adverse events, the underlying anatomy has to be understood and thoughtfully targeted. Clinical observations indicate that eyebrow ptosis can be avoided if neuromodulators are injected in the upper forehead, despite the frontalis muscle being the primary elevator. METHODS: Twenty-seven healthy volunteers (11 men and 16 women) with a mean age of 37.5 ± 13.7 years (range, 22 to 73 years) and of diverse ethnicity (14 Caucasians, four African Americans, three Asians, and six of Middle Eastern descent) were enrolled. Skin displacement vector analyses were conducted on maximal frontalis muscle contraction to calculate magnitude and direction of forehead skin movement. RESULTS: In 100 percent of investigated volunteers, a bidirectional movement of the forehead skin was observed: the skin of the lower forehead moved cranially, whereas the skin of the upper forehead moved caudally. Both movements converged at a horizontal forehead line termed the line of convergence, or C-line. The position of the C-line relative to the total height of the forehead was 60.9 ± 10.2 percent in men and 60.6 ± 9.6 percent in women (p = 0.941). Independent of sex, the C-line was located at the second horizontal forehead line when counting from superior to inferior (men, n = 2; women, n = 2). No difference across ethnicities was detected. CONCLUSIONS: The identification of the C-line may potentially guide practitioners toward more predictable outcomes for forehead neuromodulator injections. Injections above the C-line could mitigate the risk of neuromodulator-induced brow ptosis.

Soft tissue distribution pattern of facial soft tissue fillers with different viscoelastic properties.

BACKGROUND: Soft tissue filler product distribution and tissue integration have been shown to depend on myriad factors including the injector type, injector size, and injection angle. AIM: This study aims to investigate the magnitude of product spread across fascial soft tissue layers in relation to product viscoelastic properties. PATIENTS/METHODS: A total of 168 injection procedures were conducted in two female Caucasian body donors with a mean age of 80 years (range: 79-81) and a mean body mass index of 23.6 kg/m2 (range: 21.0-26.6). The injection procedures were performed in the forehead, scalp, zygomatic arch, mandible, clavicle, and sternum. The injected materials included Belotero® Soft, Belotero® Balance, Belotero® Intense, Belotero® Volume, Radiesse® , and Radiesse® Plus. Layer-by-layer dissections were performed to investigate the vertical distribution of the injected product. RESULTS: The mean product spread was for Belotero® Soft 4.54 ± 0.91; Belotero® Balance 3.85 ± 1.19; Belotero® Intense 3.04 ± 1.34; Belotero® Volume 2.58 ± 1.27; Radiesse® 1.31 ± 0.47; and Radiesse® Plus 1.27 ± 0.45 with P < .001. Bivariate correlations between product spread and storage modulus (G') revealed an inverse relationship of moderate strength with rp  = -0.651 and P < .001. CONCLUSION: The results of the present study revealed that products that were more fluid and less viscous distributed into more superficial fascial layers than products that were less fluid and more viscous (P < .001). This relationship held true irrespective of injected location.

Subperiosteal injections during facial soft tissue filler injections-Is it possible?

BACKGROUND: It can be hypothesized that safety during soft tissue filler injection could be enhanced if the product could be positioned between the periosteum and the bone surface i.e. subperiosteal. AIM: This study investigated the feasibilityof subperiosteal injections. PATIENTS/METHODS: We analysed 126 injection procedures performed in seven Caucasian body donors (4 males, 3 females) with a mean age of 75.29 ± 4.95 years [range: 70 - 87] and a mean body mass index of 23.53 ± 3.96 kg/m2 [range: 16.46 - 32.23]. The injection procedures were performed in the forehead, scalp, zygomatic arch and the mandible bilaterally. Injection procedures were conducted using 25G, 27G and 30G sharp-tip needles (TSK Laboratory, Tochigi, Japan) and at various angles from the bone surface measured with a goniometer: 90 degrees (perpendicular), 45 degrees and 10 degrees (as tangential as possible to bone surface). RESULTS: Cadaveric dissections of the injection sites showed that no product was located deep to the periosteum in any of the investigated regions. This indicates that all performed injection procedures positioned the product superficial to the periosteum (100%) with a zero-success rate of subperiosteal injections. CONCLUSION: In the setting of this cadaveric investigation, despite varying needle size and injection angle, subperiosteal injection could not be achieved. This indicates that the product can spread uncontrolled into more superficial layers yielding an increased risk for adverse aesthetic and vascular events.

How to best utilize the line of ligaments and the surface volume coefficient in facial soft tissue filler injections.

BACKGROUND: Recent advances in facial anatomy have increased our understanding of facial aging and where to best position facial soft tissue fillers. AIM: Aim of this study was to investigate a novel injection protocol which makes use of concepts like the line of ligaments or the surface - volume coefficient. MATERIALS AND METHODS: A total of 306 Caucasian patients (270 females, mean age 45.1 ± 11.4 years; 36 males, mean age 45.9 ± 11.6 years) were retrospectively investigated after the injection following a standardized protocol. This protocol comprised a total of six boluses and one retrograde fanning injections in the infraorbital area utilizing a 22G and a 25G blunt-tip cannula, respectively. Medial midfacial distances were measured using skin surface landmarks and compared after the injection of the partial and the total algorithm. RESULTS: Distances between the dermal location of the lateral SOOF and the dermal location of the mandibular ligament increased by 0.17 ± 0.11 mm with P < .001, to the corner of the mouth by 0.20 ± 0.09 mm with P < .001 and to the nasal ala by 0.20 ± 0.11 mm with P < .001. The repositioning of the facial soft tissues resulted also in a decrease of the height of the lower eyelid by 0.49 ± 0.13 mm with P < .001. CONCLUSION: The results revealed that utilizing these novel anatomic concepts, a mean amount of 0.32 cc high G-prime soft tissue filler injected in the lateral SOOF can change midfacial distances by an average of 0.19 mm.

Facial Safe Zones for Soft Tissue Filler Injections: A Practical Guide

OBJECTIVE: Vascular events are among the most dreaded complications of safe soft tissue filler injections. The aim of the present study is to present a practical guide for regional facial soft tissue filler injections, which is founded in anatomy and considers safety as its first priority. MATERIAL AND METHODS: The study sample consisted of 20 fresh (non-embalmed) hemi-faces from 10 Caucasian body donors (7 females, 3 males) with a mean age of 83.5±6.8 years and a mean BMI of 25.3±4.3 kg/m2. Injections of the upper, middle and lower faces of the body donors were performed using a commercially available hyaluronic acid based soft tissue filler. RESULTS: The results of the layer by layer dissections revealed that the injected material was separated from crucial neuro-vascular structures by fascial and/or muscular planes, which were not permeated by the product. Utilizing a single cutaneous access point per facial region, safe planes can be reached. CONCLUSION: This study provides a practical guide for safe soft tissue filler injections for the upper, middle, and lower face. Using cadaveric dissections and dyed product revealed that the targeted facial planes are separated either by fascial planes or by muscular tissue from arterial vasculature. J Drugs Dermatol. 2019;18(9):896-902.