Citations

AbstractObjectiveNeuromodulator injections of the forehead are often performed using standardized protocols. This study was designed to identify the individual skin motion pattern of the forehead and to relate this pattern to the underlying frontalis muscle morphology to offer guidance for neuromodulator placement.Material and MethodsThirty‐seven healthy volunteers (29 Caucasians, six African Americans, two Asians) with a mean age of 39.84 ± 14.4 years [range: 22‐73] were enrolled. 3D images of the forehead were analyzed using a Vectra H1 camera system computing skin displacement vectors between the noncontracted and the maximally contracted forehead of the volunteers. Relationships between the shape of the horizontal forehead lines (straight vs wavy) and the forehead motion pattern were calculated.ResultsIndependent of age or gender, a greater forehead motion angle was associated with the presence of wavy forehead lines 21.34°± 5.9 with P < 0.001, whereas straight forehead lines were associated with a smaller forehead motion angle 6.68°± 2.9 P < 0.001. Females had more frequently straight horizontal forehead lines versus males: 68.4% vs 44.4% (P = 0.037). Young volunteers (<39.8 years) did not differ in their mean forehead motion angle when compared to older volunteers (>39.8 years): 13.70°± 9.0 vs 12.39°± 8.0 with P = 0.530.ConclusionInjections of neuromodulators in the forehead can be individualized by respecting the shape of the horizontal forehead lines. Wavy lines require injection points that are located more laterally, whereas straight lines require more centrally located injection points.

Background: The deep intramuscular approach during buttock augmentation with fat grafting has been associated with a significantly increased risk for pulmonary fat embolism. This study was designed to provide guidance for injection into the subcutaneous fat. Methods: The authors investigated 150 Caucasian individuals with an equal distribution of men and women (n = 75 each) and a balanced distribution of age (n = 30 per decade: 20 to 29, 30 to 39, 40 to 49, 50 to 59, and 60 to 69 years) and body mass index (n = 50 per group: ≤24.9 kg/m2, between 25.0 and 29.9kg/m2, and ≥30 kg/m2). Ultrasound-based measurements were conducted of the thickness of the total, superficial, and deep gluteal fatty layers. Results: An increase in body mass index of 1.0 kg/m2 corresponded to an increase of 3 mm of the total gluteal subcutaneous fat of men and a 4-mm increase of the total gluteal subcutaneous fat in women. With increasing age, the thickness of the deep fatty layer increased, whereas with increasing body mass index the thickness of the superficial layer primarily increased. Formulas were generated to estimate the total thickness of the gluteal subcutaneous fatty layer for men [total thickness (in millimeters) = −33.56 + (age × 0.078) + (body mass index × 3.042)] and women [total thickness (in millimeters) = −56.997 + (age × 0.1) + (body mass index × 3.86)]. Conclusions: Knowing the total thickness of the gluteal subcutaneous fat (i.e., the safe space) allows surgeons to estimate their operating range for cannula motion even if no ultrasound machine is available during buttock augmentation with fat grafting. This can increase safety, potentially reducing the number of adverse events.

ZusammenfassungZielIn den letzten zehn Jahren hat sich unser Verständnis der Gesichtsanatomie gewandelt. Neuere minimalinvasive Eingriffe zur Gesichtsverjüngung erfordern bessere anatomische Kenntnisse.Material und MethodenIn dieser narrativen Übersichtsarbeit wird die aktuelle Literatur mit den Erfahrungen der Autoren zusammengefasst und analysiert. Sie resümiert den aktuellen Wissenstand zu oberflächlichen und tiefen fazialen Fettkompartimenten und deren Bedeutung für minimalinvasive Eingriffe am Gesicht. Ein schematisches Modell zum besseren Verständnis der komplexen Anatomie des Gesichts wurde erstellt.ErgebnisseDas Gesicht ist aus den folgenden fünf Schichten aufgebaut: Schicht 1: Haut; Schicht 2: subkutanes Fettgewebe mit Retinacula cutis (aus fibrösem Bindegewebe), Schicht 3: superfizielles muskuloaponeurotisches System (SMAS), Schicht 4: tiefes Fettgewebe und Schicht 5: Periost oder tiefe Faszie. Dieser Aufbau unterscheidet sich je nach Region, insbesondere, wenn die Ligamente in das Modell einbezogen werden. Die fazialen Fettkompartimente sind in den Schichten 2 und 4 lokalisiert. Jede Schicht hat einzigartige Merkmale und spezielle räumliche Beziehungen zu den umgebenden Geweben.SchlussfolgerungenDas neue Konzept des geschichteten Aufbaus erklärt die räumlichen Beziehungen und das funktionale Zusammenwirken der Weichteilgewebe im Gesicht. Die Kenntnis der Schichten sowie der genauen Lage der oberflächlichen und tiefen Fettkompartimente des Gesichts und ihrer Begrenzungen ist entscheidend für die sichere und effektive Durchführung minimalinvasiver Eingriffe am Gesicht.

Hands‐on dissection‐based learning of anatomy offers an unique and valued experience for medical students. Too often however, the inexperienced student's focus is to avoid damage to unfamiliar structures instead of understanding spatial relationships between structures. This results in unfortunate surrender of a critical learning experience. Additionally, approaches to dissection and anatomic exposure share little alignment to clinical approaches, making it less powerful in clinical applicability. The goal of this viewpoint commentary is based on the experience of the two authors and aims to demonstrate opportunity to introduce clinical approaches for dissection while incorporating relevant anatomical concepts in medical school curriculum that aligns with authentic healthcare practice. Using the dissections of the superficial face as a relevant and current topic of clinical interest, we point out that applying the currently performed dissection approach (medial‐to‐lateral) falls short of providing sufficient knowledge and understanding of the layered arrangement of facial structures. The lateral‐to‐medial approach, as performed in surgical face lifting procedures would offer a better understanding of the layers of the face and especially the superficial musculoaponeurotic system (SMAS) accounting for the difficulties of facial dissections on embalmed cadavers. This commentary could offer a potential change in paradigm for students and course facilitators for how to maximize the knowledge transfer during facial dissections. It potentially opens a door to rethink dissection‐based learning of anatomy toward techniques and approaches that are aligned to surgical access pathways and thus considered more clinically relevant.

SummaryObjectiveThere has been a significant shift in the understanding of facial anatomy during the last decade. Newer minimally invasive therapeutic options for facial rejuvenation procedures are increasing the need for a better knowledge of anatomy.Material and MethodsThe current literature is summarized, analyzed and presented along with the experience of the author for this narrative review, which summarizes the current understanding of the superficial and deep facial fat compartments and their relevance for minimally invasive facial procedures. A schematic facial model was created in order to facilitate a better understanding of the complexity of facial anatomy.ResultsThe face is arranged in five layers as follows: layer 1: skin; layer 2: subcutaneous fat including the retinacula cutis (composed of fibrous connective tissue); layer 3: superficial musculo‐aponeurotic system (SMAS); layer 4: deep fat; and layer 5: periosteum or deep fascia. This arrangement varies between facial regions, especially when the line of ligaments is incorporated into the model. The facial fat compartments are located in layers 2 and 4; each layer has unique characteristics and spatial relationships with the surrounding tissues.ConclusionsThe concept of the layered arrangement is a new way to understand the spatial relationship and functional interplay of the soft tissues of the face. Understanding the layers, the precise location of the superficial and deep facial fat compartments and their boundaries is crucial for the conduct of safe and effective minimally invasive facial procedures.