Case series of tongue necrosis from vascular complications after chin augmentation with hyaluronic acid: Potential pathophysiology and management.

BACKGROUND: Even though the chin is considered a safe injection area for facial filler augmentation, tongue necrosis is a rare complication in this area. OBJECTIVE: Our aim was to present case series of rare complications from chin filler augmentation with possible pathophysiology and management. METHODS: From our thorough literature search found only one case report of tongue necrosis from chin filler augmentation. We present case series of unilateral tongue necrosis from vascular occlusion following hyaluronic acid injection in the chin, which was successfully treated with a high-dose hyaluronidase injection resulting in complete recovery in all patients. RESULTS: Variation in vascular anastomosis leads to a possible cause of vascular occlusion. The lingual artery is the primary arterial supply for the tongue, which is an exclusive target for embolism. Two main responsible arteries and branches are the deep lingual and sublingual arteries. The submental artery variation was previously described as the cause of this event. We proposed potential pathophysiology of the occlusion, not only the variation of vasculature but bone. The midline lingual foramen, an anatomical bone variation on the surface of the midline inferior jaw, was found to be another possible cause. This foramen contains a branch of the submental and sublingual artery, which includes the perforating artery, median perforating artery, or both. Filler injection with a sharp needle on the bone can potentially increase the risk of this vascular incident. A high dose of hyaluronidase administered with multiplane injections was accomplished with complete recovery. CONCLUSIONS: Tongue necrosis from vascular complications after hyaluronic acid filler injection can occur. Not only vessels but bone variation pathology were possible causes.

Lower Nose Arterial Plexus and Implications for Safe Filler Injections.

BACKGROUND: The lower nose has abundant blood supply; however, nasal tip necrosis still occurs following filler injections. This study revealed the complicated pattern of the arterial supply of the lower nose. METHODS: The arterial pattern of the lower nose was studied in 40 cadavers using conventional dissections and translucent modified Sihler staining. RESULTS: Two arterial rings were connected in a figure of eight. The upper ring (nasal arterial circle) consisted of the lateral nasal and the subalar arteries encircling the nasal tip and alae. The lower ring (arterial plexus of the upper lip) was more important because of the contribution of the facial and superior labial arteries. This specific feature had not been mentioned elsewhere. CONCLUSION: Understanding this specific feature of the blood supply of the lower nose is essential for aesthetic physicians to perform the appropriate techniques during filler injection procedures in the nasal and perioral regions.

The Columellar Arteries in the Asian Nose.

The morphologic characteristics of Asian nose are a short or retracted columella, an acute nasolabial angle, and deficient tip projection. Both operative rhinoplasty and filler rhinoplasty have been used to improve the columellar angle and the tip of the nose in Asia. However, the possibility that complications may occur following aesthetic interventions from the vascular compromises at the columella, for example, skin necrosis, deformity, and blindness. Thus, it is crucial to operate the aesthetic approach by understanding the detailed configurations of the columellar artery that might help physicians minimize the chances of adverse events.

Anatomical Study of the Dorsal Nasal Artery to Prevent Visual Complications during Dorsal Nasal Augmentation.

Dorsal nasal augmentation is a common injection associated with ocular complications. Digital compressions on both sides of the nose are recommended during injection. Considering the reported incidences of visual complications, this preventive technique may need an adjustment for more effectiveness to prevent blindness. Therefore, the dorsal nasal arteries (DNAs) were studied by conventional dissections in the subcutaneous and fibromuscular tissues of the nasal dorsum in 60 embalmed cadavers. The results showed that among the 60 faces, 32 faces had bilateral DNAs (53.3%), 23 had dorsal nasal plexus with minute arteries (38.3%), and five had a single dominant DNA (8.3%). The DNA originated from one of the four arterial sources, which influenced the location and course of the artery. These sources included the ophthalmic angular arteries in 21 faces (56.8%), terminal ophthalmic arteries in two faces (5.4%), lateral nasal arteries in 11 faces (29.7%) and facial angular arteries in three faces (8.1%). Consequently, the dominant dorsal nasal artery running close to the midline found in 8% of the cases could make side compressions during nasal dorsum augmentation less effective from preventing ocular complications. However, an adjustment of digital compressions which combines pinching and side compressions is suggested to improve the safety.

Clinical implications of the arterial supplies and their anastomotic territories in the nasolabial region for avoiding arterial complications during soft tissue filler injection.

INTRODUCTION: The nasolabial fold (NLF) causes particular concern during aging in the middle face region. However, arterial complications of filler injections at this site have been continually reported during recent years. The aim of this study was to investigate the arterial locations and their anastomotic pathways related to filler injection sites in the NLF. MATERIALS AND METHODS: Thirty hemi-faces of 15 embalmed Thai cadavers were dissected. Three anatomical landmarks of NLFs were assigned: the inferior margin level (NLF1), the mid-philtral horizontal line level (NLF2), and the inferior alar level (NLF3). Ten hemi-faces of five soft embalmed Thai cadavers underwent a modified Sihler's staining procedure to investigate the arterial anastomoses. RESULTS: The artery closest to all of the landmarks was the facial artery. It was located inferomedial to NLF1 in 28%, and the mean distances along the X- and Y-axes were 3.53 ± 2.11 mm and 3.53 ± 1.75 mm, respectively. It was also located medial to NLF2 in 52.1% with an X-axis distance of 4.93 ± 1.53 mm. Several arteries were located close to NLF3, including the facial (33.3%), lateral nasal (33.3%), and infraorbital (30.0%) arteries. Anastomoses of the nasolabial arteries served to connect both the external-external and internal-external carotid systems. CONCLUSIONS: Several arteries are located close to NLF1-NLF3. To prevent arterial injury, the locations and anastomotic pathways, as possible sources of severe complications, should be recognized prior to NLF filler injection.

Cadaveric Dissections to Determine Surface Landmarks Locating the Facial Artery for Filler Injections.

BACKGROUND: The facial artery is a high-risk structure when performing filler injections at the nasolabial fold, buccal, and mandibular regions. OBJECTIVES: This study aimed to establish reference landmarks locating the course of the facial artery and its essential branches. METHODS: Thirty-one embalmed cadavers were enrolled in this study. The course of the facial artery was observed in regard to the following reference points: masseter insertion, oral commissure, and common bony landmarks. The corner of the mouth was utilized as the landmark to measure the turning point of the facial artery. RESULTS: Seven points were established to identify the course and turning point of the facial artery. These included the anterior masseteric, lateral mental, infraorbital, medial canthal, basal alar, post-modiolar (PMP), and supra-commissural (SCP) points. The course of the facial artery deviates at least twice at the lateral mental points and at the SCP or PMP. The facial artery appeared more medially when the artery turned at the PMP and SCP. It presented through the lateral channel if the turning point was solely at the PMP. Wherever the facial artery deviates, it can be divided into 3 segments: the mandibular, buccal, and nasolabial segments. The arterial course may deviate laterally from the mouth corner towards PMP. The nasolabial segment may also deviate laterally to the basal alar point at the alar grove for 0.5 to 1 cm. CONCLUSIONS: The deviation of facial artery closely relates with mandibular, buccal, and nasolabial segments. It is essential in avoiding arterial injury for physicians and surgeons who perform procedures in these areas.

Localization and Topography of the Arteries on the Middle Forehead Region for Eluding Complications Following Forehead Augmentation: Conventional Cadaveric Dissection and Ultrasonography Investigation.

Forehead augmentation with filler injection is one of the most dangerous procedures associated with iatrogenic intravascular injection resulting in the severe complications. Nonetheless, few studies have determined the explicit arterial localization and topography related to the facial soft tissues and landmarks. Therefore, this study aimed to determine an arterial distribution and topography on the middle forehead region correlated with facial landmarks to grant an appropriate guideline for enhancing the safety of injection. Nineteen Thai embalmed cadavers were discovered with conventional dissection and 14 Thai healthy volunteers were investigated with ultrasonographic examination on the middle forehead. This study found that at the level of mid-frontal depression point, the transverse distance from the medial canthal vertical line to the superficial and deep branches of supraorbital artery were 9.1 mm and 15.1 mm, respectively. Whereas the depths from the skin of these arteries were 4.1 mm and 4.3 mm, respectively. Furthermore, the frontal branch of superficial temporal artery was detectable in 42.1% as an artery entering the forehead area. At the level of lateral canthal vertical line, the vertical distance of frontal branch was 31.6 mm, and the depth from skin of the artery was 2.7 mm. In conclusion, a proper injection technique could be performed based on an intensive arterial distribution and topography, and ultrasonographic examination before the injection is also suggested in order to restrict the opportunity of severe complications.

Implication of Location of the Ascending Mental Artery at the Chin Injection Point.

BACKGROUND: Facial proportions can be improved by means of chin augmentation in patients with a receding chin. The ascending mental artery is the main arterial supply to the top of the chin, and arterial occlusion of this artery can result in soft-tissue infarction. This study aims to measure the topographic anatomy of the ascending mental artery at the chin injection area, using a three-dimensional camera. METHODS: Thirty-one embalmed cadaveric faces were dissected at the chin. The midline of the inferior margin of the mandibular protuberance was marked with a pin. A variation in size between the two opposite ascending mental arteries was noticed. The depth of the artery from the skin surface and distance from the midline were measured using a three-dimensional camera. RESULTS: There were 19 dominant ascending mental arteries on the right and 12 on the left. The dominant ascending mental arteries enter the chin paracentrally, approximately 6 mm (mean ± SD, 5.64 ± 4.34 mm) from the midline, within the muscular plane, and at a depth of 4.15 ± 1.95 mm from the skin. Furthermore, the artery formed an anastomosis with the sublingual artery, within the floor of the mouth. CONCLUSION: Every aesthetic physician should recognize the course of the ascending mental artery and use the appropriate techniques to avoid vascular injury during chin augmentation using filler injections.

Anatomical and ultrasound-based injections for sunken upper eyelid correction.

BACKGROUND: A needle or a cannula can be safely used during filler injection procedures to correct a sunken upper eyelid. To date, there are no precise injection points recommended that are based on an anatomical study. OBJECTIVE: This study systematically investigated the vascular pattern and depth of forehead arteries at the periorbital area of upper eyelid. METHODS: Twenty cadavers were dissected in this study. Additional data were obtained from 30 healthy volunteers using Doppler ultrasound imaging with high-frequency probe. RESULTS: The ophthalmic artery divided into two opposite primary branches: the superior and inferior orbitoglabellar arteries running along the orbital rim. After the supratrochlear artery arose from the superior orbitoglabellar artery at the medial eyebrow, the supraorbital artery either divided from this artery near the supraorbital foramen or emerged as an individual artery from the supraorbital notch. The inferior orbitoglabellar artery gave off the radix artery superior to the medial canthal tendon. The radix artery divided into two opposite branches: the dorsal nasal artery going to the nose and the paracentral artery going to the glabella. Ultrasound imaging revealed a subcorrugator space that a cannula can safely pass through. At the supraorbital foramen/notch, the supraorbital artery traveled very close to the bone. Based on the anatomical data collected, the following injection points for a needle and a cannula technique are recommended. CONCLUSION: Correction of a sunken upper eyelid is a dangerous procedure which should be performed only by experienced physicians. However, with precise anatomical knowledge and correct techniques, optimal outcomes can be safely achieved.

Anatomical and Ultrasonography-Based Investigation to Localize the Arteries on the Central Forehead Region During the Glabellar Augmentation Procedure.

Glabellar augmentation is one of the most popular cosmetic procedures but can entail severe complications caused by inadvertent intravascular injection of filler. Nevertheless, few studies have investigated the arteries on the glabellar and central forehead regions. The aim of this study was to correlate the topography and location of the arteries in this area with anatomical landmarks to propose a safety guideline. Two methods were used to investigate the glabellar and central forehead areas: dissection of 19 Thai embalmed cadavers, and ultrasonographic examination of 14 healthy Thai volunteers. At the level of the glabellar point, the horizontal distances from the midline to the arteries were 4.7 mm (central artery), 7.8 mm (paracentral artery), and 14.7 and 19.2 mm (superficial and deep branches of supratrochlear artery). The depths from the skin of the arteries were 3.1 mm (central artery), 4.8 mm (paracentral artery), and 4.2 and 5.9 mm (superficial and deep branches of supratrochlear artery). The periosteal artery was detected in 71.1% as a branch of either the superior orbitoglabellar or the supratrochlear artery. It ran in the supraperiosteal layer for a short course and penetrated the periosteum above the superciliary ridge or above the medial eyebrow, adhering tightly to the bony surface. This study suggests a safe injection technique for the glabella based on a thorough knowledge of arterial distribution and topography and color Doppler ultrasonographic examination prior to the injection, which is recommended to minimize the risk of severe complications. Clin. Anat. 33:370-382, 2020. © 2019 Wiley Periodicals, Inc.

Ethnic differences in platysmal perforators and its relevance for the platysma myocutaneous flap.

BACKGROUND: Variable flap loss rates for the platysma myocutaneous flap have been reported for the Caucasian and the Asian population, which are 10.1% and 1.6%, respectively. This study was designed to investigate ethnic differences in the number and location of platysmal perforators that influence flap survival rates. METHODS: The number and location of platysmal perforators were investigated in a total of 60 platysma muscles: bilaterally in 20 Caucasian (13 males and 7 females) and 10 Asian (5 males and 5 females) specimens using cadaveric dissections. Adjustment for inter-individual variability in platysma length and width was performed by standardizing each x-value to mandibular length and each y-value to mandibulo-clavicular distance. RESULTS: A total of 64% of all detected platysmal perforators were found in the medial half of the muscle following the pathway of the external carotid artery. Individuals of Caucasian ethnicity had a mean number of 7.60 ± 2.0 perforators per side, whereas individuals of Asian ethnicity had a mean number of 13.05 ± 1.76 perforators per side (p < 0.001). Individuals of Asian ethnicity had a statistically significant increased number of platysmal perforators in the medial middle (2.95 ± 1.05 vs. 1.60 ± 1.08; p < 0.001) and lower (1.60 ± 1.35 vs. 0.73 ± 0.85; p = 0.003) regions of the platysma compared to those of Caucasian individuals. CONCLUSION: A significantly higher number of platysmal perforators were identified in the investigated Asian population. This provides a potential explanatory model for the reported lower platysma myocutaneous flap loss rates in the Asian population than in the Caucasian population.

Investigation of the presence and variation of the ascending mental artery: Conventional dissections and ultrasonographic study.

BACKGROUND: Tongue and mouth floor infarction following filler injections for chin augmentation is a rare complication that has the increase in incidence been reported. OBJECTIVE: This study investigated the arterial anastomosis between the submental and sublingual arteries that can lead to the emboli and subsequent tongue infarction during chin augmentation. METHODS: Forty-two formaldehyde-embalmed cadavers and four soft-embalmed cadavers were dissected to verify the incidence and source of the ascending mental artery. Ultrasonographic study of the artery was performed in 10 healthy volunteers. Attention was paid to discriminate whether the ascending mental artery arose from the submental artery or the sublingual artery using the arch of the mylohyoid muscle as the discriminating landmark. RESULTS: Incidence of ascending mental artery from the sublingual artery was 7.1% in the studied population. All ascending mental arteries were 0.7 ± 0.2 mm in diameter at the mental protuberance and were branches of the submental artery that arose from the facial artery, except for two arteries that arose from the sublingual artery. Ultrasonographic study revealed that one left and one right sublingual artery from the lingual arteries penetrated the mylohyoid muscle near the midline to become the ascending mental artery in two volunteers. The ascending mental artery from the other side continued from the submental artery. CONCLUSION: Findings from the cadaveric dissections and ultrasonographic study revealed that the ascending mental artery may be a branch that continues from the lingual artery, or communicates with the sublingual artery through the mouth floor.

Translucent and Ultrasonographic Studies of the Inferior Labial Artery for Improvement of Filler Injection Techniques.

Lower lip augmentation by filler injection is an aesthetic procedure essential for achieving a feminine look and to enhance attractiveness. Complications as a result of injury to the inferior labial artery can result in undesirable outcomes. METHODS: The translucent technique was used to study the origin of the inferior labial artery in 11 cadavers. Ultrasonography of the inferior labial artery was also performed in 20 volunteers, which provided supplemental data to this study, in relation to establishing recommendations for filler injection. RESULTS: Five different types of inferior labial artery were described. These types were found in various combination patterns. Types 2, 4, and 5 are more vulnerable to arterial injury during filler injection. Ultrasonography revealed a depth of 6 mm and an arterial position at the vermillion border as the dangerous injection plane. CONCLUSION: The origins and courses of the inferior labial artery are classified into 5 types. These types are often found in combination with each other in different faces, resulting in large anatomical variation between people. Types of combination influence severity of lower lip necrosis when arterial injury occurs. The physician should be aware of these anatomical variations during aesthetic treatments and reconstructive procedures to avoid the dangers of accidental arterial injury.

The Feasibility Determination of Risky Severe Complications of Arterial Vasculature Regarding the Filler Injection Sites at the Tear Trough.

BACKGROUND: The tear trough is a significant sign of periorbital aging and has usually been corrected with filler injection. However, the arterial supply surrounding the tear trough could be inadvertently injured during injection; therefore, this study aimed to evaluate the nearest arterial locations related to the tear trough and investigate the possibility of severe complications following filler injection. METHODS: Thirty hemifaces of 15 Thai embalmed cadavers were used in this study. RESULTS: The artery located closest to both the inferior margin (TT1) and mid-pupil level (TT2) of the tear trough was found to be the palpebral branch of the infraorbital artery. Furthermore, at 0.5 mm along the tear trough from the medial canthus (TT3), the angular artery was identified, which was found to be a branch of the ophthalmic artery. The artery at TT1 and TT2 was located beneath both the zygomaticus major and the orbicularis oculi muscles. The distances from TT1 to the artery were measured as follows: laterally, 2.79 ± 1.08 mm along the x axis; and inferiorly, 2.88 ± 1.57 mm along the y axis. For the TT2, the artery was located inferomedially from the landmark of 4.65 ± 1.83 mm along the x axis and 7.13 ± 3.99 mm along the y axis. However, the distance along the x axis at TT3 was located medially as 4.00 ± 2.37 mm. CONCLUSION: The high risk of injury to the artery at the tear trough should be considered because of the numerous arteries to this area.

Ultrasound evaluation of arterial anastomosis of the forehead.

BACKGROUND: Color Doppler ultrasound has a potential role as an imaging guide in aiding filler injections which are blinded procedures. OBJECTIVE: This study investigated the forehead arteries and provided insight into their anastomoses. This was performed by challenging their function to provide blood through these anastomoses when the main artery was temporary occluded by compression. METHODS: Three arteries were identified on each side of the forehead, the supratrochlear, the supraorbital and the superficial temporal arteries. Under ultrasound monitoring, each target artery and corresponding anastomosis was studied separately by compressions performed in a sequential and accumulative manner. RESULTS: Data from the current study imply that accidental cannulation of either the supratrochlear artery or the supraorbital artery can cause ophthalmic artery embolization in every case recorded. If the frontal branch of the superficial temporal artery is cannulated, the chance of blindness as a complication occurs in one fifth of volunteers. Anastomosis between both sides of the terminal branches of ophthalmic arteries creates the possibility of bilateral ocular complications when accidental cannulation occurs at one of these branches, especially the supratrochlear artery. Thus, injury to the supratrochlear artery carries a greater risk of complication than the supraorbital artery. CONCLUSION: These findings emphasize that the chance of ocular complication is less when accidental cannulation occurs at the superficial temporal artery compared with injury to the supratrochlear or the supraorbital arteries as the terminal branches of the ophthalmic artery. Ultrasound can assist in the identification and evaluation of all the arteries at risk, thus avoiding the occurrence of vascular complications.

Safe Planes for Injection Rhinoplasty: A Histological Analysis of Midline Longitudinal Sections of the Asian Nose.

BACKGROUND: Dorsal nasal augmentation is an essential part of injection rhinoplasty on the Asian nose. Aesthetic physicians require detailed knowledge of the nasal anatomy to accurately and safely inject filler. METHODS: One hundred and thirty-five histological cross sections were examined from 45 longitudinal strips of soft tissue harvested from the midline of the nose, beginning from the glabella to the nasal tip. Muscles and nasal cartilage were used as landmarks for vascular identification. RESULTS: At the nasal tip, a midline longitudinal columellar artery with a diameter of 0.21 ± 0.09 mm was noted in 14 cadavers (31.1 %). At the infratip, subcutaneous tissue contained cavernous tissue similar to that of the nasal mucosa. The feeding arteries of these dilated veins formed arteriovenous shunts, into which retrograde injection of filler may be possible. All of the nasal arteries present were identified as subcutaneous arteries. They coursed mainly in the superficial layer of the subcutaneous tissues, with smaller branches forming subdermal plexuses. A substantial arterial anastomosis occurred at the supratip region, in which the artery lay in the middle of the subcutaneous tissue at the level of the major alar cartilages. These arteries had a diameter ranging between 0.4 and 0.9 mm and were found in 29 of 45 specimens (64.4 %). This was at the level midway between the rhinion above the supratip and the infratip. This anastomotic artery also crossed the midline at the rhinion superficial to the origin of the procerus on the lower end of the nasal bone. Here the arterial diameter ranged between 0.1 and 0.3 mm, which was not large enough to cause arterial emboli. Fascicular cross sections of the nasalis muscle directly covered the entire upper lateral cartilage. The subdermal tissue contained few layers of fat cells along with the occasional small artery. The procerus arose from the nasal bone and was continuous with the nasalis in 16 cadavers (35.6 %). There was fatty areolar tissue between the procerus and the periosteal layer and no significant arteries present. The procerus ascended beyond the brow to insert into the frontalis muscle with very few cutaneous insertions. The supratrochlear vessels and accompanying nerve were occasionally found on the surface of the frontalis muscle. CONCLUSION: Most nasal arteries found in the midline are subcutaneous arteries. Filler should be injected deeply to avoid vascular injury leading to compromised perfusion at the dorsum or filler emboli at the nasal tip. LEVEL OF EVIDENCE V: This journal requires that the 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.