Anatomical Continuation Between the Sub-Superficial Musculoaponeurotic System Fat and Retro-Orbicularis Oculi Fat: The True Nature of the Retro-Orbicularis Oculi Fat

Safe Zones for Facial Fillers: Anatomical Study of SubSMAS Spaces in Asians

The study "Spaces of the Face for Filler Procedures: Identification of subSMAS Spaces Based on Anatomical Study" explores the anatomy of facial spaces crucial for safe and effective filler injections. By delineating the subSMAS (sub-superficial musculoaponeurotic system) spaces, this research highlights how these virtual compartments, bordered by fat, muscles, fascia, and ligaments, facilitate independent muscle movement and reduce the risk of damaging critical structures. The thicker and more robust skin of East Asians necessitates deeper filler injections, emphasizing the significance of accurately identifying these spaces. A cadaver study with dyed gelatin validated the existence and characteristics of these subSMAS spaces, confirming their safety for filler procedures. Key spaces, such as the subgalea-frontalis, interfascial and temporalis, and prezygomatic spaces, were examined, illustrating safe zones for injections. The findings underscore the importance of anatomical knowledge for enhancing facial aesthetics while minimizing complications. This study serves as a guide for clinicians to perform precise and safe filler injections, providing a foundation for further research on the dynamic interactions of these spaces and long-term outcomes.

Singular entry point technique for forehead and temple filler augmentation: Anatomical and clinical perspectives

BACKGROUND

The depressed volume of the forehead and temple is resolved by filler injection. However, the current method has the potential to cause pain and side effects in patients, depending on the skill of the clinician. Therefore, this study proposes a new method for safer and simpler injection using only one injection entry point.

METHODS

Using the novel injection method, the filler was injected into the forehead and temple regions in three unembalmed cadavers and two healthy Korean volunteers. The cannula and filler locations were identified using dissection, ultrasonography, and three-dimensional (3D) scanning.

RESULTS

Ultrasonographic images and dissection results showed that the filler injected into the cadavers was in the target layer. The cannula and filler were located on the layer as the supraperiosteal layer on the forehead and the supra deep temporal fascia layer in the temple. Finally, 3D scanning images showed that the filler was injected precisely and effectively into the forehead and temples of the volunteer who underwent the procedure.

CONCLUSIONS

This method can reduce pain and minimize externally visible wounds caused by injections. The injected filler was naturally connected from the forehead to the temple and maintained for around 3 months. Additionally, it is possible to inject fillers into the forehead and temple at a constant and safe depth without requiring specific skills. It is expected that this method will become a universal method because it minimizes the burden on both patients and clinicians.

SMAS repositioning technique utilizing cog thread: Anatomical perspectives

INTRODUCTION

Face-lifting surgeries were once common among individuals over 60 years old due to skin laxity, but recent trends favor thread lifting in this age group. Understanding dynamic changes in facial anatomy during postural shifts is essential.

METHOD

Fresh cadaver studies have demonstrated the passage of threads through the superficial musculoaponeurotic system (SMAS) layer, confirming the efficacy of the technique. Proper insertion depth targeting SMAS repositioning, rather than superficial skin layers, is crucial.

RESULT

The natural movement of tissues secured by thread (N-Cog and N-Fix, N-Finders Inc., Korea) insertion results in lifting effects. However, complications may arise if threads affect deeper facial muscles, leading to discomfort. Fibrous septa play a significant role in guiding thread placement, with different densities influencing thread maneuverability and tissue response during lifting.

CONCLUSION

Procedures targeting SMAS repositioning using threads aim to maintain the new position of relocated tissues. Understanding structural variations in facial regions informs thread selection and placement. Aligning threads with tissue movement and the intended SMAS layer positioning is vital to prevent complications. Balancing thread insertion depth and tissue traction is critical for successful outcomes. Modern thread lifting techniques prioritize SMAS repositioning, enhancing lifting effects while ensuring procedure safety and efficacy.

Experimental study on clinical and morphological determination of the optimal cannula diameter for lipoaspirate harvest from rabbit inguinal fat pad

Determining the most appropriate cannula diameter for lipoaspirate harvesting is important, both in terms of the quality and composition of the material obtained, and the ease of practical use of the cannula. The size of the cannula is one of the main factors affecting the qualitative characteristics of the obtained lipoaspirate sample for further use of adipose tissue. The purpose of the investigation was to clinically and histomorphometrically determine the optimal cannula diameter for lipoaspirate samples collection from rabbit inguinal fat pad in an experimental study. The methods of Animal models, Surgical procedures, Macroscopic examination, Histological examination, and Morphometric study were applied. There is a direct correlation between the percentage of connective tissue fibres in the lipoaspirate and the diameter of the cannula. The lack of clear criteria for selecting a lipoaspiration cannula is one of the limitations to obtaining generally accepted lipoaspiration protocols with subsequent use of adipose tissue. In this study, the animal experiment determined the most ideal cannula diameter suitable for collecting the largest amount of lipoaspirate for subsequent use.

Analysis of facial ultrasonography images based on deep learning

Transfer learning using a pre-trained model with the ImageNet database is frequently used when obtaining large datasets in the medical imaging field is challenging. We tried to estimate the value of deep learning for facial US images by assessing the classification performance for facial US images through transfer learning using current representative deep learning models and analyzing the classification criteria. For this clinical study, we recruited 86 individuals from whom we acquired ultrasound images of nine facial regions. To classify these facial regions, 15 deep learning models were trained using augmented or non-augmented datasets and their performance was evaluated. The F-measure scores average of all models was about 93% regardless of augmentation in the dataset, and the best performing model was the classic model VGGs. The models regarded the contours of skin and bones, rather than muscles and blood vessels, as distinct features for distinguishing regions in the facial US images. The results of this study can be used as reference data for future deep learning research on facial US images and content development.

Three-Dimensional Arterial Distribution Over the Midline of the Nasal Bone

BACKGROUND

A comprehensive understanding of arterial variations around the midline of the nose is of great importance for the safety of filler injection.

OBJECTIVES

The aim of the study was to clearly define the 3-dimensional location of the arteries along the midline of the nasal bone.

METHODS

The arterial structures overlapping the nasal bone along the midline were observed in 79 cadavers.

RESULTS

The present study found that 0 to 3 named arteries per nose segment could be identified. All the arterial structures were located in or above the superficial musculoaponeurotic system layer overlapping the nasal bone. The probability of encountering named arteries at 5 defined points, P1 to P5, was 5/79 (6.3%), 4/79 (5.1%), 1/79 (1.3%), 6/79 (7.6%), and 9/79 (11.4%), respectively. The depth of the main arterial trunk was 1.2 ± 0.4 mm, 1.6 ± 0.6 mm, 1.8 ± 0 mm, 1.0 ± 0.4 mm, and 0.9 ± 0.5 mm below the skin at P1 to P5, respectively.

CONCLUSIONS

The authors confirmed that sub-superficial musculoaponeurotic system injection along the midline through a needle is anatomically reliable and that a technique with 1 entry point through the rhinion via a cannula can easily keep the needle sufficiently deep for safe nasal filler injection.