Evaluation of Intraarterial Thrombolysis in Treatment of Cosmetic Facial Filler-Related Ophthalmic Artery Occlusion

The role of oculoplastic surgeons in minimally invasive cosmetic injectables

PURPOSE OF REVIEW

In recent years, the field of aesthetic medicine has witnessed a paradigm shift with an increasing demand for minimally invasive cosmetic procedures, including cosmetic injectables. This review aims to delineate the distinctive role played by oculoplastic surgeons in the administration of cosmetic injectables, comparing their expertise to that of nonphysician practitioners.

RECENT FINDINGS

Complications arising from cosmetic injections are discussed, including skin discoloration, inflammation, necrosis, vision loss, retinal pathology, and central nervous system adverse effects. Injector expertise, patient factors, type of filler, location of injection, and management strategies are reviewed. Findings highlight diverse practitioner involvement, common adverse effects like skin necrosis and vision loss, with hyaluronic acid fillers being prominent. Areas at the highest risk for ocular complication include the glabella and nose with potential management involving dissolving fillers and reducing pressure. Emphasis is placed on expert injector selection and patient awareness.

SUMMARY

The administration of cosmetic injectables requires a profound understanding of facial anatomy, vasculature, and potential complications. In contrast to nonphysician practitioners, oculoplastic and aesthetic surgeons bring a level of anatomical precision and clinical acumen that is essential for navigating the complexities of cosmetic injectables. Emphasis on training and collaboration among practitioners will be essential in advancing the field while prioritizing patient safety and satisfaction.

Cerebral Complications Following Facial Autologous Fat Graft Injection: A Systematic Review and Meta-analysis

BACKGROUND

With the increasing use of autologous fat (AF) grafting in plastic surgery, the occurrence of complications has garnered the attention from plastic surgeons. This study aims to estimate the cerebral complications following facial AF graft injection objectively and systematically with newly published literature.

METHODS

A comprehensive literature search was conducted systematically on PubMed, Embase, Web of Science, Cochrane, and ClinicalTrials.gov for articles published between 2000 and 2023. A systematic review and meta-analysis were performed in accordance with PRISMA guidelines.

RESULTS

A total of 11 articles comprising of 37 participants were included, all of which are case reports. For AF facial filling, the incidence rate of cerebral embolism among cases of cerebral and ocular embolism was found to be 60% (95% CI 0.41-0.79). The incidence of cerebral embolism presenting with initial symptoms of unconsciousness was 69% (95% CI 0.48-0.9), with limb movement disorders was 55% (95% CI 0.26-0.84), and with vision loss was 30% (95% CI 0.12-0.49). The incidence of cerebral embolism with ophthalmic artery occlusion was 36% (95% CI 0.20-0.53), compared to was 71% (95% CI 0.48-0.95) without ophthalmic artery occlusion.

CONCLUSIONS

AF grafting is generally safe and minimally invasive. However, with its widespread use as facial injection filling for cosmetic enhancement, the incidence of cerebral complications, such as cerebral infarction, has also increased. It is imperative to properly manage high-risk factors for cerebral embolism during the perioperative period to prevent its occurrence.

LEVEL OF EVIDENCE III

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 .

[Forehead injections: Anatomy, technics, products]

Knowledge of anatomy not only allows optimal treatment and therefore full satisfaction of our patients, but is also fundamental in the prevention of complications. A thorough understanding of aging allows for effective treatments, as most patients demand a natural result, removing the inevitable signs of aging, which can only be understood by considering their aging. Facial aging is a natural but complex multifactorial process, particularly for the forehead. In this article, we will focus on botulinum toxin as well as fillers in aging.

"Filler-Associated Acute Stroke Syndrome": Classification, Predictive Modelling of Hyaluronidase Efficacy, and Updated Case Review on Neurological and Visual Complications

INTRODUCTION

The rising use of soft tissue fillers for aesthetic procedures has seen an increase in complications, including vascular occlusions and neurological symptoms that resemble stroke. This study synthesizes information on central nervous system (CNS) complications post-filler injections and evaluates the effectiveness of hyaluronidase (HYAL) treatment.

METHODS

A thorough search of multiple databases, including PubMed, EMBASE, Scopus, Web of Science, Google Scholar, and Cochrane, focused on publications from January 2014 to January 2024. Criteria for inclusion covered reviews and case reports that documented CNS complications related to soft tissue fillers. Advanced statistical and computational techniques, including logistic regression, machine learning, and Bayesian analysis, were utilized to dissect the factors influencing therapeutic outcomes.

RESULTS

The analysis integrated findings from 20 reviews and systematic analyses, with 379 cases reported since 2018. Hyaluronic acid (HA) was the most commonly used filler, particularly in nasal region injections. The average age of patients was 38, with a notable increase in case reports in 2020. Initial presentation data revealed that 60.9% of patients experienced no light perception, while ptosis and ophthalmoplegia were present in 54.3 and 42.7% of cases, respectively. The statistical and machine learning analyses did not establish a significant linkage between the HYAL dosage and patient recovery; however, the injection site emerged as a critical determinant.

CONCLUSION

The study concludes that HYAL treatment, while vital for managing complications, varies in effectiveness based on the injection site and the timing of administration. The non-Newtonian characteristics of HA fillers may also affect the incidence of complications. The findings advocate for tailored treatment strategies incorporating individual patient variables, emphasizing prompt and precise intervention to mitigate the adverse effects of soft tissue fillers.

LEVEL OF EVIDENCE III

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 .

Superselective Arterial Hyaluronidase Thrombolysis is an Effective Treatment for Hyaluronic Acid-Induced Retinal Artery Occlusion: Study in a Rabbit Model

BACKGROUND

There are serious complications associated with hyaluronic acid (HA) facial injections, including vision impairment due to retinal artery ischemia. In this study, we put forth a clinically relevant model of retinal ischemia and reperfusion in rabbit. We used this to verify the efficacy of hyaluronidase intra-artery thrombolysis in the treatment of hyaluronic acid-induced retinal artery occlusion.

METHODS

Retinal artery ischemia was induced by injecting HA into the ophthalmic artery (OA) of adult chinchilla rabbit, and reperfusion was achieved by intra-artery thrombolysis therapy with hyaluronidase following 60 min and 4 h of occlusion. Digital subtraction angiography (DSA) and fundus fluorescein angiography (FFA) were used to evaluate blood flow in the retina. Electroretinogram (ERG), hematoxylin and eosin staining and transmission electron microscope were used to evaluate the structure and function of the retina after ischemia and reperfusion following 60 min and 4 h of occlusion.

RESULTS

DSA and FFA images confirmed occlusion of the ophthalmic and central retinal arteries, as well as reperfusion after hyaluronidase thrombolysis. ERG indicated retinal dysfunction following ischemia, and thrombolysis partially rescued its impairment following 4 h of occlusion. Hematoxylin and eosin staining and TUNEL staining revealed ischemia-induced histological damages in the retina at different time windows, and hyaluronidase thrombolysis partially mitigated these damages.

CONCLUSIONS

We report a method to establish a HA-induced retinal artery occlusion animal model. Hyaluronidase intra-artery thrombolysis was used to recanalize the embolized OA at different time points. Using our method, we achieved retinal reperfusion, and an improvement was observed in the visual function of rabbits after hyaluronidase thrombolysis following 4 h of occlusion. We believe that hyaluronidase intra-artery thrombolysis is an effective method to treat HA-induced retinal artery occlusion in clinic.

LEVEL OF EVIDENCE II

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 .

Exploring Superselective Intraarterial Thrombolysis for Autologous Fat Injection-Induced Vision Loss

BACKGROUND

Intravascular injection represents the most severe complication in fat transplantation procedures. Currently, the prognosis for patients who suffer from blindness due to fat transplantation-induced ocular vascular occlusion is far from optimistic.

OBJECTIVES

The aim of this study was to explore and evaluate the efficacy and safety of arterial thrombolysis in the treatment of ocular vascular occlusion caused by fat transplantation.

METHODS

We analyzed the data of 12 patients who underwent intraarterial thrombolysis and conservative treatments for facial autologous fat grafting-associated ocular vascular occlusion. Among the cases, there were 6 instances of ophthalmic artery embolism and 6 cases of central retinal artery occlusion. All patients suffered with sudden blindness, sometimes accompanied by eye pain, ptosis, strabismus, skin necrosis at the injection site, or cerebral microinfarction. They received symptomatic conservative treatments and intraarterial thrombolysis, encompassing mechanical vessel recanalization, vessel dilation, and dissolution of thrombus constituents.

RESULTS

Following intraarterial thrombolysis, a noteworthy improvement in the blood flow of both the main trunk and peripheral branches of the ophthalmic artery was observed in the majority of patients when contrasted with their pretreatment status. One patient experienced a headache intraoperatively, while no significant discomfort was reported by the remaining patients. After conservative treatments and intraarterial thrombolysis, all patients experienced improvement in ocular symptoms, skin necrosis, and cerebral infarction. Three patients demonstrated improvement in visual acuity. These patients had surpassed the recommended time window for treatment, yet the occlusion of the ophthalmic artery was not complete.

CONCLUSIONS

Intraarterial thrombolysis combined with conservative treatments achieves early perfusion and is expected to promote visual recovery. Hospitals that possess the necessary treatment capabilities are encouraged to establish this therapeutic pathway.

A Scoping Review of Hyaluronidase Use in Managing the Complications of Aesthetic Interventions

BACKGROUND

Hyaluronidase is used as an adjunct or main treatment to manage complications associated with cosmetic hyaluronic acid (HA) filler injections such as necrosis, blindness, hypersensitivity, delayed nodules, and poor aesthetic outcomes.

OBJECTIVE

To systematically map the available evidence and identify the gaps in knowledge on the effectiveness of hyaluronidase use in managing the aesthetic complications associated with HA injections (vascular occlusion, blindness, nodules, delayed hypersensivity, granuloma, poor aesthetic outcome).

METHODS

PubMed, Medline, Embase and Cochrane databases were used up to May 2022, to look for randomized clinical trials (RCTs), clinical trials, and retrospective case-control studies reporting on the use of hyaluronidase for managing the HA filler injection complications.

RESULTS

The database search yielded 395 studies; of those 5 RCTs (all carried out in the USA) were selected (53 subjects), indicating the effectiveness of hyaluronidase for removal of un-complicated injected HA nodules (forearm, upper arm, or back skin). The follow-ups ranged from 14 days to 4 years. The amount of HA filler injected into each site varied from 0.2 to 0.4 mL. A dose dependent response was observed for most HA fillers. No major adverse reactions were reported. Overall, for removal of every 0.1 mL of HA filler they injected 1.25-37.5 units of hyaluronidase (single injections). When 3 consecutive weekly hyaluronidase injection was used much lower doses of 0.375-2.25 unit was utilised. There was no evidence in a form of RCTs, clinical trials, and retrospective case-control studies on the removal/reversal of HA injections in the facial skin, or management of over-corrections, inflammatory nodules, or tissue ischemia/necrosis associated with HA filler injection.

CONCLUSION

Based on studies on the forearm, upper arm and back skin, hyaluronidase can be used for the reversal of uncomplicated HA filler injection nodule. However, further adequately powered studies are warranted to establish the ideal treatment protocol/dose of hyaluronidase for reversal of HA filler injections in the facial region or management of complications associated with aesthetic HA injection.

LEVEL OF EVIDENCE III

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 .

Facial cosmetic injection: A bibliometric analysis of research status and hotspots

BACKGROUND

The increasing popularity of cosmetic injections using various fillers and neuromodulators for facial rejuvenation has brought both new opportunities and challenges to this field.

AIM

Our study was designed to employ bibliometric and visual analysis for a qualitative and quantitative evaluation of facial cosmetic injections, as well as to identify research trends and hotspots in this field.

METHODS

All publications covering facial cosmetic injection during 2002-2023 were retrieved and extracted from the Web of Science database. The VOSviewer 1.6.18 software and the online tool (http://bibliometric.com/) were applied to analyze the publication trend.

RESULTS

A total of 3797 articles related to facial cosmetic injection were identified during the period 2002-2023. The United States had the largest volume of publications (1520, 40.0%), followed by China (333, 8.8%) and Germany (282, 7.3%). Among the institutions and journals, the University of California system and Plastic and Reconstructive Surgery accounted for the most papers related to facial cosmetic injection, respectively. Facial anatomy and injection techniques, prevention and management of complications, regenerative medicine, efficacy and safety of various soft-tissue fillers, as well as botulinum toxin injections for facial rejuvenation were identified as hotspots for facial cosmetic injections.

CONCLUSIONS

Facial cosmetic injections are showing an increasing trend in terms of both the number of published papers and operations performed. Despite the notable advancements in this field, numerous challenges persist, including safety concerns and the level of research evidence. With the emergence of novel technologies and materials, scholars from diverse countries and institutions should engage in more extensive collaboration, thereby directly expediting the progress of this field.

Would hyaluronic acid-induced mental bone resorption be a concern? A prospective controlled cohort study and an updated retrospective cohort study

BACKGROUND

Hyaluronic acid (HA) is a widely used filler for face contouring and is generally believed to be safe and effective. However, there have been reports of HA-related bone erosion in the chin area without clear scientific data regarding its existence, incidence, and severity. This exploratory study was to evaluate HA-related mental bone resorption through a prospective, controlled, observer-blind, nonrandomized clinical trial and a retrospective cohort study.

METHODS

On the one hand, a prospective, controlled, nonrandomized, single-shot HA-injection clinical trial was conducted. Computed tomographic scans were collected at baseline and at 6-12 months of follow-up for both HA-injection and control groups. On the other hand, an updated retrospective cohort study compared the HA-injection with a blank control group. The primary outcomes composed of three quantitative parameters [bone resorption index (BRI M and BRI N ), bone resorption thickness ratio] and one subjective evaluation index (severity ranking). Information about demographics, complications, and injection volume were also recorded.

RESULTS

From June 2021 to March 2023, 78 patients were prospectively recruited for the study. There was a significant association between HA-injection and bone resorption [BRI M : pre (84.24±8.10%) vs post (79.21±8.70%), P <0.001; BRI N : pre 92.50% (73, 144%) vs 87.99% (63, 132%), P <0.001; bone thickness ratio: HA 24.08% (0, 48%) vs control 0 (0, 17%), P <0.001]. However, there was no difference in large-volume (>1 ml) and small-volume (≦1 ml) injection subgroups [bone resorption thickness ratio: (21.50±10.91%) vs (24.51±11.92%), P =0.350]. The imaging manifestation revealed discernible bone resorption in 35.90% of the patients, with an median bone resorption thickness ratio of 24.08%. Between October of 2019 and March 2023, 95 HA-injection patients (190 semimandibular cases), 95 normal controls were enrolled. The BRI M was significantly lower in the HA-injection group compared to the controls ( P <0.001).

CONCLUSIONS

HA may induce bone resorption in the mentum. Large-scale randomized controlled clinical trial is warranted for further confirmation. Patients should be informed of this potential complication.

Disastrous cerebral and ocular vascular complications after cosmetic facial filler injections: a retrospective case series study

Soft tissue filler injections are among the most popular facial rejuvenation methods. Cerebral infarction and ophthalmic artery occlusion are rare and catastrophic complications, especially when facial cosmetic fillers are injected by inexperienced doctors. Radiologists and plastic surgeons need to increase their awareness of the complications associated with fillers, which allows early diagnosis and intervention to improve patient prognosis. Regarding the mechanism by which vascular occlusion occurs after facial filler injections, a retrograde embolic mechanism is currently the predominant theory. Numerous case reports have been presented regarding complications associated with injections of facial aesthetics. However, the small sample sizes of these studies did not allow for an adequate assessment of the clinical and imaging manifestations based on the location of the occlusion and the type of filler, and detailed elaboration of multiple cerebral infarctions is also lacking. Therefore, this study aimed to investigate the clinical and radiological features of severe cerebral and ocular complications caused by cosmetic facial filler injections. In addition, we discuss the pathogenesis, treatment, and prognosis of these patients. The clinical, computed tomography (CT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA) findings were described and analysed. Radiological examinations are crucial for demonstrating severe complications, and brain MRI is especially strongly suggested for patients with cosmetic filler-induced vision loss to identify asymptomatic cerebral infarctions. Extreme caution and care should be taken during facial injections by plastic surgeons.

Percutaneous Intra-arterial Hyaluronidase Injection for Hyaluronic Acid Filler Embolism Threatening Skin Barrier Integrity: Implementation of a Stepwise Treatment Protocol

BACKGROUND

Hyaluronic acid (HA) filler-induced vascular embolism that threatens skin integrity is an urgent situation. There is increasing evidence that percutaneous intra-arterial hyaluronidase injection is an effective therapeutic technique for it. However, until now, there is a lack of a unifying protocol about the technique.

OBJECTIVES

This study aims to provide a conclusion of percutaneous intra-arterial hyaluronidase injection along with adjunctive measures on the treatment of occlusions precipitated by HA-based filler and develop a stepwise treatment protocol.

METHODS

We searched PubMed for peer-reviewed studies, consensus statements, case series, and case reports using a variety of keywords.

RESULTS

High-dose, pulsed hyaluronidase is the mainstay for the treatment of HA filler-induced embolism, but percutaneous intra-arterial hyaluronidase injection is a more effective technique. Until now, hyaluronidase is injected into three arteries percutaneously, including facial artery, supratrochlear artery, and superficial temporal artery. Furthermore, the adjunctive measures that may optimize clearance of an occlusion and/or skin barrier repair such as the use of image guidance and CGF should be considered.

CONCLUSION

Vascular occlusions that threaten skin integrity are an urgent matter which requires accurate diagnosis and effective intervention. Percutaneous intra-arterial hyaluronidase injection along with adjunctive measures performed in a stepwise manner is key to an optimal outcome.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .

The Efficacy and Safety of Hyaluronic Acid Injection in Tear Trough Deformity: A Systematic Review and Meta-analysis

BACKGROUND

Hyaluronic acid (HA) injection is an effective method to correct tear trough deformity. Nevertheless, the quantitative data of cosmetic results and complications of HA injection in tear troughs remained unemployed. The purpose of this meta-analysis was to synthesize the current quantitative data on the aesthetic outcomes and adverse effects of tear trough deformity correction with HA injection.

METHODS

This meta-analysis consulted PubMed, Embase, Web of Science, Scopus and Cochrane databases based on the search terms published before September 2022. Data extracted was analyzed to evaluate the satisfaction rates and complications of HA injection. Meta-analysis was performed using the random-effect model for overall and subgroup analysis.

RESULTS

This meta-analysis comprised 31 reports involving 2556 participants. The pooled overall satisfaction rate was 91.0% (95% CI 84.9-95.7%). The pooled rates of swelling/edema and bruising/ecchymosis were 19.2% (95% CI 10.4-29.9%) and 18.4% (95% CI 10.1-28.4%), respectively. The pooled rates of redness/erythema, contour irregularity/lump and blue discoloration/Tyndall effect were 7.1% (95% CI 1.5-15.6%), 5.3% (95% CI 1.8-10.2%) and 0.9% (95% CI 0.0-2.5%), respectively.

CONCLUSIONS

The present meta-analysis manifested a low risk of complication rate and a high satisfaction rate in tear trough rejuvenation with HA injection.

LEVEL OF EVIDENCE I

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 .

Administration Method and Potential Efficacy of Hyaluronidase for Hyaluronic Acid Filler-Related Vision Loss: A Systematic Review

BACKGROUND

With the global increase in the use of injectable fillers, more cases with serious adverse events such vision loss are being reported. This article aims to review the cases of hyaluronic acid (HA) filler-related vision loss and to discuss the potential efficacy of hyaluronidase (HYASE) treatment via different given methods.

METHODS

A total of 29 articles presenting 144 cases of HA filler-related vision loss were included in this study.

RESULTS

Most cases of HA filler-related vision impairment were reported from China, followed by Korea. The majority of cases were seen in women. The nose, forehead and glabella were the most commonly injection sites. All cases had vision impairment and nearly all cases were unilateral with immediate onset of visual signs and symptoms. Ophthalmic artery occlusion (OAO) and central retinal artery occlusion (CRAO) were the two most commonly involved arterial obstruction patterns featured with a very poor prognosis followed by branch retinal artery occlusion (BRAO), the most favorable involved arterial pattern for a better prognosis. HYASE given subcutaneously and intra-arterially helped with visual recovery to different degrees, while retrobulbar HYASE seemed to be less helpful.

CONCLUSION

Complications after HA-based filler injection are extremely rare but can cause disastrous visual impairment. HYASE given subcutaneously and intra-arterially helped with visual recovery to different extents, and the efficacy might be reinforced when performed together, while retrobulbar HYASE seemed to be less helpful. However, to accurately access the efficacy of HYASE via different administration methods, further randomized controlled trials are needed.

LEVEL OF EVIDENCE III

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 .

Cosmetic Filler-Induced Vascular Occlusion: A Rising Threat Presenting to Emergency Departments

Vascular emergencies from cosmetic filler-induced vascular occlusion represent an iatrogenic etiology that poses a threat to patients, with sequelae that range from disfiguring skin necrosis to blindness and stroke. As cosmetic fillers continue to grow in popularity, the importance of early identification, triaging, and management of these rare but potentially disabling injuries has motivated efforts to educate the public and professional audiences. In this practice review article, we outline components of acute care pertaining to these injuries based on evolving practice guidelines and best evidence recommendations.

[Effectiveness and interest of retrobulbar hyaluronidase injections in the treatment of blindness complicating facial hyaluronic acid injections: A literature review]

INTRODUCTION

Hyaluronic acid injections are becoming increasingly common among both the general public and the medical community, but they are not without risks. The occurrence of blindness, although rare, is a tragic event for both the patient and the practitioner. One of the treatments proposed in the literature is to inject hyaluronidase as close as possible to the site of ischemia, retrobulbarly. The aim of our study is to evaluate the effectiveness and potential benefits of retrobulbar hyaluronidase injections.

MATERIALS AND METHODS

A literature review was conducted using the PubMed database. Only articles addressing retrobulbar hyaluronidase injections for the treatment of blindness following hyaluronic acid injections were included.

RESULTS

We identified 12 case reports or series, comprising a total of 16 patients. Among these 16 patients, 3 regained their vision. Hyaluronidase was injected between 20minutes and 7days after the onset of the complication, with injected doses ranging from 3×150IU to 3×1500IU.

DISCUSSION

Literature reveals only 3 cases of successful treatment out of the 16 reported injections. The time interval before retrobulbar injection, as well as the dose and the experience of the injecting practitioner, may influence the success rate of this treatment. Other treatments, such as intravascular hyaluronidase injections, remain to be explored.

Retrospective Study of Vascular Complications Caused by Hyaluronic Acid Injection

BACKGROUND

Complications from intravascular embolization of hyaluronic acid (HA) are not only no longer uncommon but also devastating. This study aimed to examine clinical aspects of patients referred to our hospital for care following complications from intravascular filler embolization.

METHODS

We retrospectively reviewed data from all patients referred to our medical center for the management of complications associated with intravascular embolization of HA fillers including demographics, medical history, clinical features, and treatment between November 2013 and June 2022.

RESULTS

A total of 116 patients with vascular complications (27 cases with vision loss and 89 cases with skin necrosis) were assessed. The highest risk injection sites for skin necrosis included the nasal region (58/115, 50.4%), temple (16/115, 13.9%), and forehead (11/115, 9.6%) and for vision loss included the nasal region (18/30, 60.0%) and forehead (7/30, 23.3%). In skin necrosis cases, a needle (60/89, 67.4%) carried a higher risk than that of a cannula (29/89, 32.6%), whereas in vision loss cases, nasal dorsum injections using a cannula (16/27, 59.3%) carried a higher risk than that observed using a needle (11/27, 40.7%). No treatment was completely successful in reversing these complications.

CONCLUSION

Intravascular embolization of HA filler is a serious complication. Although some combination treatments have been proposed, there is no standard protocol for treating severe complications.

LEVEL OF EVIDENCE III

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 http://www.springer.com/00266 .

Is constant needle motion during soft tissue filler injections a safer procedure? A theoretical mathematical model for evaluating patient safety

BACKGROUND

The safety rationale behind the constant needle motion injection technique is based on the assumption that due to the constant needle motion and simultaneous soft tissue filler material administration a smaller amount of product per area may be injected into an artery if an artery within the range of the moving needle is inadvertently entered.

OBJECTIVE

To perform mathematical calculations for determining the probability for causing intra-arterial product administration when constantly moving the needle during facial aesthetic soft tissue filler injections.

METHODS

This study was designed as a theoretical investigation into the probabilities for causing adverse events due to intravascular injection of soft tissue filler material when constantly moving a 27-G needle during facial soft tissue filler administration.

RESULTS

It was revealed that with a higher number of conducted injection passes a greater soft tissue area can be covered by the needle. The odds of encountering an artery within the covered soft tissue volume and the odds of injecting any volume greater than zero into the arterial blood stream increases with the number of performed injection passes. This increase is greatest between 1 and 10 performed injection passes.

CONCLUSION

This model demonstrates that the constant needle motion technique increases the probability of encountering an artery within the treatment area and thus increases the odds for intra-arterial product administration. The constant needle motion technique does not increase safety but rather may increase the odds of causing intra-arterial product administration with the respective adverse consequences for the patient.

A roadmap for safety during facial filler injections: A fresh frozen cadaver study

BACKGROUND

Filler injections are commonly applied to reshape facial contouring. However, cadaveric injections of filler for facial contouring on the whole face, followed by anatomic analysis and measurement, have rarely been reported. This study aimed to provide comprehensive anatomical information, including topographies and roadmap of injection point entry, penetration depth, filler location, the hierarchy of facial structure, and vital vascular course.

METHODS

Thirty faces on fresh frozen cadaver heads were used for this anatomic study. The whole face was divided into seven facial zones and 14 injection points for penetration depth measurement and cadaveric injection. Static periosteum injections with a sharp-needle technique were performed. Specimens were then dissected to observe the precise locations of fillers and their relationships with surrounding anatomic structures.

RESULTS

The topography of penetration depth gradually increased from the upper face to the middle face, lower face, and temporal region. Most of the injected hyaluronic acid filler flowed backward to the loose areolar tissue layer between the superficial musculoaponeurotic system and periosteum or deep fascia. Multilevel layer distributions and anastomosis of the vessels were found in the face, especially in the glabella, dorsum nasi, and temporal regions.

CONCLUSIONS

This study can provide clinicians with a comprehensive reference for facial contouring injections: topographies of the injection point and penetration depth and the vascular anatomical structure in high-risk facial zones. The static periosteum injection with effective aspiration is recommended as a relatively safe technique. Clinicians are supposed to grasp the anatomy and injection technique to achieve maximum safety during filler injections.

Post-rhinoplasty complications with previous hyaluronic acid injection history: Cerebral infarction and vision loss

BACKGROUND

Rhinoplasty is becoming increasingly frequent as the pursuit of aesthetics by people accelerates. In recent years, the proportion of people opting for rhinoplasty injections has gradually increased. This has led to numerous reports citing catastrophic postoperative complications such as skin necrosis, cerebral infarction, and visual impairment.

AIM

The aim of our report is to discuss the possible etiological factors for this post-rhinoplasty complication and provides a rationale for HA injection history as a risk factor in rhinoplasty.

METHODS

We report a rare case that received nasal HA injections in the past without any untoward incident. She opted for a second rhinoplasty 2 years after her initial nasal HA injections. This second intervention led to post-injection loss of vision in one eye and cerebral infarction. Following clinical and radiological examination, digital subtraction angiography (DSA) and superselective intra-arterial thrombolysis were performed.

RESULTS

The patient did not develop disuse exotropia or ocular atrophy, but the left eye remained without light perception, which implies that intra-arterial thrombolytic therapy may be a positive and effective method to maintain the normal appearance of the eye.

CONCLUSION

It is advisable for patient safety to maintain a long interval of time between hyaluronidase injection and repeat rhinoplasty. Clinicians should become familiar with the anatomical peculiarities of the patient and be gentle during the rhinoplasty procedure.

Preservation of Eschar Prevents Excessive Wound Healing by Reducing M2 Macrophages Polarization

Background

Removal of the eschar has gradually become a consensus on treatments of deep dermal necrosis after skin trauma in recent years, whereas exaggerated scar contracture and tissue proliferation developed during healing have received little attention. Here, the authors investigated the effects of eschar on excessive wound healing of small dermal damage and focused on the role M2 macrophages played, hoping to offer a theoretical basis to improve patients' cosmetic satisfaction.

Methods

A mouse dorsal wound model (n = 12) was established by electric heating pads heating for 20 seconds on each side of the spine, and the left side was the preserved group. Macrophage numbers, expression of wound-healing-associated proteins, and inflammatory cytokine levels were assessed at different time points by immunohistochemistry and quantitative real-time polymerase chain reaction. A co-culture system of M2 macrophages and myofibroblasts was created in vitro. Immunohistochemistry, real-time polymerase chain reaction, and Western blot were performed to evaluate the proliferation, migration, and protein expression of myofibroblasts.

Results

Preserving eschar inhibited contraction-associated proteins (α-smooth muscle actin and vimentin) and collagen expression, inflammatory cytokine (IL-1β, IL-10, TFN-α, and IL-4) expression, and M2 macrophage infiltration. Mechanistically, M2 macrophages potentially contributed to excessive wound healing by promoting myofibroblasts proliferation, migration, and production of contraction-associated proteins.

Conclusion

Eschar preservation in wounds could reduce inflammation and negatively modulate myofibroblasts by inhibiting M2 macrophage polarization and infiltration, preventing excessive wound contraction and collagen deposition.

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.

Case report and literature review: fatal cerebral fat embolism following facial autologous fat graft

Background

Severe cerebral artery embolism is a rare complication of facial autologous fat injection. However, its incidence has markedly increased with the recent rise in facial cosmetic procedures.

Case presentation

We report a 31-year-old Chinese woman who presented with unconsciousness 6 h after having undergone a facial autologous fat injection. A neurological examination revealed stupor, bilaterally diminished pupillary light reflexes, right-sided central facial palsy, and no reaction to pain stimulation of right limbs. Diffusion-weighted imaging displayed patchy hyperintense lesions in the left frontal, parietal, and temporal lobes. Magnetic resonance angiography demonstrated fat embolism in the left internal carotid artery, anterior cerebral artery, and middle cerebral artery. We immediately performed mechanical thrombectomy under sufficient preoperative preparations but failed to achieve complete recanalization. Pathological examination of the embolus confirmed the presence of adipocytes. Although we actively administered symptomatic and supportive treatments, the patient eventually died due to the progression of cerebral herniation and systemic infection.

Conclusion

Due to the ineffectiveness of current treatment and the inferior prognosis, fat embolism, a severe complication of autologous fat graft, should draw the attention of both plastic surgeons and neurologists so that actions may be taken for both its prevention and treatment.

Clinical Manifestations and Prognosis of Embolism Caused by Filler Injection in Different Facial Regions

Background

Embolism is a serious complication after facial filling, with a usually poor prognosis of the symptoms after embolism. The authors systematically reviewed reported cases of facial vascular embolism, explored the relationship between the location and material used for facial filling and occurrence of vascular embolism, and assessed the prognosis of complications after vascular embolism.

Methods

This study provides a systematic review of published cases of vascular embolism after facial filling. A summary of the filling materials and filling sites for each case, the adverse reactions and embolized blood vessels, a recording of the time when each patient experienced adverse reactions and started treatment, and a presentation of their prognosis are provided.

Results

The frontal, eyebrow, and nose are common filling sites causing facial embolism. The main clinical manifestations after embolism were visual impairment, skin necrosis, and ptosis. The prognosis of visual impairment after embolization was poor, whereas skin necrosis and ptosis generally improved after treatment.

Conclusions

This article aimed to review the clinical manifestations, therapies, and prognosis of embolism after facial filling. A better understanding of these complications can help clinicians to detect the occurrence of complications as early as possible and give patients timely treatment.

A novel predictive model for phthisis bulbi following facial hyaluronic acid cosmetic injection

PURPOSE

To observe long-term prognosis of anterior segment ischemia (ASI) following hyaluronic acid (HA) injection, propose a severity grading system for ASI and a predictive model for phthisis bulbi (PB) based on long-term secretion dysfunction of ciliary process.

METHODS

This is a retrospective case-control study. All enrolled 20 patients were divided into two groups and followed for at least 6 months to observe the formation and transformation characteristics of ASI and long-term prognosis based on the degrees of ciliary function damage.

RESULTS

The severity of ASI following HA injection could be subdivided into 4 grades according to the degrees of ciliary function damage, comprising ASI grades 0, 1, 2 and 3. In 20 patients, ophthalmoplegia at 1-month follow-up, ASI within 1 month, ASI at 1-month follow-up, hypotony within 6 months were all significantly more common in study group than in control group (60% vs. 0%, P = 0.011; 100% vs. 20%, P = 0.001; 100% vs. 0%, P < 0.001; 80% vs. 0%, P = 0.001, respectively). Sensitivity, specificity and the area under the receiver operating characteristic curve (AUC) for predicting subsequent PB at 2-year follow-up through the co-occurrence of ophthalmoplegia at 1-month follow-up and hypotony within 6 months was 100%, 100% and 1.00, respectively.

CONCLUSIONS

The new grading system for ASI and novel predictive model for PB we proposed could predict the long-term prognosis and probability of subsequent PB due to ASI following HA injection through several dynamic assessments within 6 months.

LEVEL OF EVIDENCE

Level IV, observational prognostic study.

Long-term Prognosis of Vision Loss Caused by Facial Hyaluronic Acid Injections and the Potential Approaches to Address This Catastrophic Event

BACKGROUND

Vision loss is a serious complication of hyaluronic acid (HA) filler injections, and long-term observations regarding the prognosis, particularly with angiography, are rare.

OBJECTIVES

This study aimed to investigate the long-term prognosis and living status of patients with visual defects due to HA filler injections.

METHODS

Nine patients with vision loss caused by HA filler injections and receiving different treatments were included and followed up for 2 to 6 years after their accident. Follow-ups, including outpatient ophthalmologic examinations, were performed.

RESULTS

In the follow-up observation, all patients had reintegrated into society and work. The prognosis was similar for all hyaluronidase treatments, including retrobulbar injections and superselective ophthalmic artery thrombolysis. The facial appearance was not remarkably affected, and only 3 patients reported slight scarring. Ptosis disappeared in all the patients, and slight strabismus was found in 5 patients. However, vision improvement was very limited, even in the patients whose occluded retinal central artery received reperfusion.

CONCLUSIONS

This long-term follow-up showed that the patients with vision loss caused by HA filler injections could reintegrate into society after treatment. Although the embolization of the retinal central artery led to reperfusion, vision was not restored, which further demonstrated the difficulty of recovering vision with the current treatment and the importance of prophylaxis. Autohydrolysis of HA by incorporating hyaluronidase-containing stimuli-responsive nanoparticles and a dual-pipe syringe are potential future approaches to address this catastrophic event.

Efficacy of Percutaneous Superficial Temporal Arterial Hyaluronidase Injection for Hyaluronic Acid Filler-Induced Necrosis of Frontotemporal Skin and/or the Ipsilateral Scalp With Subsequent Alopecia

BACKGROUND

Necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia after hyaluronic acid (HA) filler injection into the temple is rare complications with superficial temporal artery embolization are suspected as the major pathological mechanism. The main treatment currently is intralesional hyaluronidase (HAase) injection, but the effectiveness of percutaneous superficial temporal arterial HAase injection still lacks consensus.

OBJECTIVES

To investigate the effectiveness of superficial temporal arterial HAase injection in dissolving HA filler-induced necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia.

METHODS

Five recent clinical cases with necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia after HA filler injection into the temple were analyzed retrospectively. The patients underwent HAase injection via superficial temporal artery combined with adjunctive treatments, and the clinical progress was observed.

RESULTS

Significant improvement was observed in terms of necrosis of frontotemporal skin and the ipsilateral scalp after treatment, and the patients were relieved of their clinical symptoms. Alopecia occurred approximately 1 to 2 weeks after HA filler injection, and the well-defined alopecia areas were formed 15 to 20 days after HAase injection. Patients were followed for 3 to 6 months. During follow-up, the skin lesions of all patients were restored to near normal appearance. Hair regrowth was observed 2 to 3 months after HAase treatment, and hair density nearly reached the normal level 3 to 4 months later.

CONCLUSIONS

Percutaneous superficial temporal arterial HAase injection is an effective treatment option for HA filler-induced necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia.

LEVEL OF EVIDENCE: 4

Ultrasound-Guided Targeted vs Regional Flooding: A Comparative Study for Improving the Clinical Outcome in Soft Tissue Filler Vascular Adverse Event Management

BACKGROUND

Adverse vascular event management following hyaluronic acid-based aesthetic injections relies on the administration of hyaluronidase which is capable of enzymatically degrading the injected product and improving clinical symptoms. Two protocols are currently available to manage such complications: "ultrasound-guided targeted" and "flooding".

OBJECTIVES

The aim of this study was to compare the 2 protocols in terms of the volume of hyaluronidase utilized, and the onset and degree of clinical improvement.

METHODS

A comparative case series of 39 patients was retrospectively evaluated. The patients were initially treated with the "flooding" protocol and then treated with the "ultrasound-guided targeted" protocol due to no or little improvement.

RESULTS

The "ultrasound-guided targeted" protocol utilized a mean [standard deviation] total of 122.5 [34] IU of hyaluronidase, whereas the "flooding" protocol utilized 1519.4 [1137] IU, which represents a statistically significant reduced amount of injected hyaluronidase (P = 0.028). There was no clinical improvement in 92.3% and only little improvement in 7.7% of the treated patients following the first applied "flooding" protocol, but there was a 100% immediate improvement when subsequently treated with the "ultrasound-guided targeted" protocol. Ultrasound imaging revealed that the application of hyaluronidase restored normal blood flow both in the perivascular space and in the superficially located subdermal soft tissues.

CONCLUSIONS

Despite its limitations in study design, this retrospectively evaluated case series revealed that the "ultrasound-guided targeted" protocol utilized less hyaluronidase and restored clinically visible symptoms faster. The effect of this protocol is best explained by the perforasome concept which will need to be investigated further in future studies.

LEVEL OF EVIDENCE: 4

Bridging a Century-Old Problem: The Pathophysiology and Molecular Mechanisms of HA Filler-Induced Vascular Occlusion (FIVO)—Implications for Therapeutic Interventions

Biocompatible hyaluronic acid (HA, hyaluronan) gel implants have altered the therapeutic landscape of surgery and medicine, fostering an array of innovative products that include viscosurgical aids, synovial supplements, and drug-eluting nanomaterials. However, it is perhaps the explosive growth in the cosmetic applications of injectable dermal fillers that has captured the brightest spotlight, emerging as the dominant modality in plastic surgery and aesthetic medicine. The popularity surge with which injectable HA fillers have risen to in vogue status has also brought a concomitant increase in the incidence of once-rare iatrogenic vaso-occlusive injuries ranging from disfiguring facial skin necrosis to disabling neuro-ophthalmological sequelae. As our understanding of the pathophysiology of these injuries has evolved, supplemented by more than a century of astute observations, the formulation of novel therapeutic and preventative strategies has permitted the amelioration of this burdensome complication. In this special issue article, we review the relevant mechanisms underlying HA filler-induced vascular occlusion (FIVO), with particular emphasis on the rheo-mechanical aspects of vascular blockade; the thromboembolic potential of HA mixtures; and the tissue-specific ischemic susceptibility of microvascular networks, which leads to underperfusion, hypoxia, and ultimate injury. In addition, recent therapeutic advances and novel considerations on the prevention and management of muco-cutaneous and neuro-ophthalmological complications are examined.

Superselective Ophthalmic Artery Thrombolytic Therapy for Hyaluronic Acid Embolization: A Case Report

Blindness caused by embolization of fillers is a rare but catastrophic complication after cosmetic injection. Vision improvement is rarely reported among the various studies on potential clinical treatments. In this case, the patient suffered from ophthalmic artery occlusion with no light perception 48 h after hyaluronic acid injection. After two intra-arterial thrombolytic therapy sessions and traditional sequential therapy, ocular appearance was restored to normal, blood supply to the retina and visual function were improved, and visual acuity was restored to hand motion levels. Our results suggest that intra-arterial thrombolytic therapy with hyaluronidase and papaverine has a positive effect on hyaluronic acid-induced visual loss and is worthy of clinical promotion.

Expert recommendations on the assessment and management of complications due to hyaluronic acid soft tissue filler injections in Asians

BACKGROUND

The use of hyaluronic acid (HA) fillers for medical aesthetic purposes is increasing worldwide. Nonetheless, adverse events do occur because of patient-specific issues, injection technique, or product factors. It would be mandatory to consider cultural and anatomical features of Asians in preventing and managing the complications of HA injections.

METHODS

Literature search of studies looking at current evidence and guidelines on the management of complications following HA filler injections in Asian patients was conducted. This was followed by an expert group discussion that was convened to reach consensus recommendations on the best clinical practices.

RESULTS

The expert panel provided specific recommendations focusing on the safe use of soft tissue fillers in Asian patients, including early identification of adverse events and how to prevent and comprehensively manage these outcomes.

CONCLUSIONS

Here, we provide consensus statements of Asian experts in dermatology, plastic surgery, ophthalmology, and aesthetic medicine mainly focusing on AEs with higher risk for Asians and can be used to guide physicians in treating Asian population.

Efficacy of Percutaneous Intraarterial Facial/Supratrochlear Arterial Hyaluronidase Injection for Treatment of Vascular Embolism Resulting From Hyaluronic Acid Filler Cosmetic Injection

BACKGROUND

Vascular embolism is a serious complication of hyaluronic acid (HA) filler cosmetic injection, and hyaluronidase injection has been proposed as the treatment. Until now, there has been a lack of adequate clinical evidence regarding the benefits of treatment for HA filler-induced vascular embolism by percutaneous facial or supratrochlear arterial hyaluronidase injection.

OBJECTIVES

The authors sough to evaluate the efficacy of percutaneous facial or supratrochlear arterial hyaluronidase injection as a rescue treatment for HA filler-induced vascular embolism.

METHODS

We included 17 patients with vascular embolism after facial HA filler injection. Intraarterial injection of 1500 units hyaluronidase was performed via facial artery for 13 cases with skin necrosis and via supratrochlear arterial for 4 cases with severe ptosis and skin necrosis but no visual impairment. Simultaneously, general symptomatic treatment and nutritional therapy were performed.

RESULTS

After hyaluronidase injection, facial skin necrosis in all cases was restored and ptosis in the 4 cases was also significantly relieved. Patients were subsequently followed-up for 1 month to 1 year. The skin necrosis in 16 patients completely healed, and only 1 patient had small superficial scars.

CONCLUSIONS

It is effective to alleviate skin necrosis and ptosis resulting from HA filler embolism via percutaneous facial or supratrochlear arterial hyaluronidase injection.

LEVEL OF EVIDENCE: 4

Super-selective intra-arterial dissolution therapy for lingual artery occlusion resulting due to the use of hyaluronic acid for chin augmentation: The first reported case

As a consequence of the current trend of performing minimally invasive surgery, the use of injectable fillers has progressively increased in aesthetic surgery. Vascular complications resulting due to filling of hyaluronic acid (HA) in the chin have been previously reported. However, clinical evidence regarding the results of treatment of lingual artery occlusion with super-selective intra-arterial dissolution is lacking. Herein, we reported a case of lingual artery occlusion resulting due to HA filling for which tongue arteriography and catheter-directed dissolution were implemented via femoral artery intubation for the first time in the literature. The aim of this paper is to discuss the rare complications arising due to chin augmentation and their treatment to provide a deeper understanding of the use and side effects of HA in this procedure.

Significant Vision Recovery from Filler-Induced Complete Blindness with Combined Intra-Arterial Injection of Hyaluronidase and Thrombolytic Agents

With the increase of cosmetic injectable hyaluronic acid (HA), there have been more cases with serious complications, including skin necrosis, blindness, and cerebral embolism. Patients who have recovered from HA filler-induced total vision loss are extremely rare. We report a case of a 27-year-old female who developed severe ocular pain on the right side and total vision loss following a 1.0 ml HA filler injection in the nasal dorsum. She arrived at our hospital 4 hours later. Her visual acuity was no light perception (NLP), and she exhibited eyelid ptosis, ophthalmoplegia, and frontal and nasal ecchymosis. She was promptly treated with subcutaneous and retrobulbar hyaluronidase injections, as well as intra-arterial 1500 IU hyaluronidase injections into the right ophthalmic artery with DSA assistance. Her vision improved from NLP to counting fingers at 1.0 meters. Unfortunately, 13 hours later, she felt an intense headache, and her vision again decreased to NLP. We immediately performed an injection of 1500 IU hyaluronidase combined with 8 mg alteplase for intra-arterial thrombolysis (IAT) into the right ophthalmic artery. Her vision improved immediately afterward. After 3 months, her visual acuity had significantly recovered from NLP (admission vision status) to 20/50 (Snellen chart with glasses). Similarly, skin, conjunctival, eye movement, and ptosis symptoms completely recovered. This case demonstrates that reversal of complete blindness due to embolism of the ophthalmic and central retinal arteries could be accomplished through multidisciplinary therapies, especially IAT using fibrinolytic agents combined with hyaluronidase followed by an anticoagulant regimen.Level of evidence VThis 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 Table of Contents or online Instructions to Authors www.springer.com/00266 .

Fat Embolism After Autologous Facial Fat Grafting

BACKGROUND

Autologous facial fat grafting has gained popularity in recent years and is considered to be safe. This paper presents the case of a patient who died due to massive cerebral microfat embolism after facial fat grafting.

OBJECTIVES

The aim of this study was to raise awareness and provide more evidence on the prevention and treatment of this potentially lethal complication of facial fat grafting.

METHODS

A detailed report was made of the case. Two online databases were searched for similar cases of facial fat embolism resulting in neurologic and/or visual symptoms. Thereafter a literature search was conducted to verify the etiology, current treatment options, and preventive measures.

RESULTS

Forty-nine cases with similar events were found in the literature. The most common injected area was the glabella (36.1%), and an average of 16.7 mL fat was injected. The main complications were visual impairment, with 88.5% of cases resulting in permanent monocular blindness, and neurologic symptoms, some of which never fully recovered. Including the present patient, 7 cases were fatal. Fat embolism can occur in the veins and arteries of the face. Two possible pathways for fat embolism exist: the macroscopic, mechanical pathway with immediate signs, and the microscopic, biochemical pathway with delayed symptoms. Mechanical embolectomy and corticosteroids are suggested treatment options but evidence for their efficacy is lacking. Several different preventive measures are described.

CONCLUSIONS

Although facial fat grafting is considered a safe procedure, one should be aware of the risk of fat embolism. Underreporting of this adverse event is likely. With no effective treatment and often detrimental outcomes, preventive measures are of utmost importance to improve patient safety.

LEVEL OF EVIDENCE: 4

Cerebral Embolism as a Result of Facial Filler Injections: A Literature Review

Background

With the growth in the popularity of facial filler injections, increased numbers of severe adverse events, such as cerebral embolism, have been reported.

Objectives

The aim of this article was to summarize the clinical manifestations and proposed mechanisms of filler-induced cerebral embolism (FICE).

Methods

A literature review was performed with the search keywords “filler injection,” “hyaluronic acid,” “fat graft,” “cerebral infarction,” “cerebral embolism,” “stroke,” “cerebrovascular infarction,” “disorders of consciousness,” and “hemiplegia.”

Results

Among the 43 cases of FICE enrolled from 35 articles, 37 patients were female, and 6 were male. Twenty-nine of these patients had received fat grafting, and 12 hyaluronic acid injection. Most FICE patients had been injected in the glabella, followed by the temporal, forehead, and nasal areas. Among 30 patients injected under local anesthesia, 43.33% presented with neurologic symptoms during the procedure. The main symptoms were consciousness disorders and hemiplegia. Most of the embolization sites were in the middle cerebral artery, followed by frontal lobe infarction and anterior cerebral artery infarction. Three patients developed cerebral hemorrhage after embolism. Twenty-six patients presented with newly acquired vision loss. The management for FICE cases included embolectomy, thrombolysis, decompressive craniectomy, antiplatelet/anticoagulant therapy, and symptomatic and nutritional treatment. Nearly half of the patients recovered or exhibited improved neurologic manifestations but not visual loss. Five patients died.

Conclusions

FICE is a severe complication following facial filler injection. Careful prevention, timely identification, and treatment are crucial to decreasing the morbidity and mortality of FICE.

Level of Evidence: 4

Thrombogenicity of Hyaluronic Acid Fillers: A Quantitative Thrombodynamics Study

PURPOSE

At present, there is a paucity of data regarding the thrombogenicity of hyaluronic acid fillers (HAFs). This article quantitatively analyses the thrombogenicity of 2 commonly used HAFs: Restylane Lyft and Juvéderm Ultra.

METHODS

Thrombogenicity was assessed using the Thrombodynamics Analyzer System and plasma obtained from healthy controls. Following the addition of HAFs or control, spontaneous clot formation time, initial rate of clot growth, average rate of clot growth over 30 minutes, and clot size at 30 minutes was measured for each sample. The median of differences between each group were analyzed.

RESULTS

Nine individuals with a mean (SD) age of 37 (17) years, participated in the study. Initial rate of clot growth was significantly lower in plasma mixed with Juvéderm compared to control (p = 0.008) or Restylane (p = 0.038). The average rate of clot growth more than 30 minutes was significantly lower in both HAF groups (Restylane vs. control p = 0.038; Juvéderm vs. control p = 0.008), there was no significant difference between HAF groups (p = 0.635). Final clot size was significantly smaller with Juvéderm (p = 0.038 vs. control and p = 0.013 vs. Restylane). Spontaneous clot formation time did not significantly change with the addition of either HAF.

CONCLUSIONS

Juvéderm significantly reduces the initial rate of clot growth, the average rate of clot growth more than 30 minutes, and clot size, whereas the addition of Restylane decreases the average rate of clot growth without affecting overall clot size in healthy individuals.

Hyaluronic Acid Embolism Treated with Subcutaneous High and Low Hyaluronidase Doses: Efficacy and Surrounding Tissue Effect

BACKGROUND

The use of hyaluronidase in hyaluronic acid vascular occlusion has been evaluated; however, the models used do not accurately assimilate the facial morphologic characteristics or study the effects on adjacent tissues. The purpose of this study was to determine an effective concentration of subcutaneous hyaluronidase to dissolve a hyaluronic acid embolism and its effect on surrounding tissue.

METHODS

Fifteen rabbits were divided into six groups. An inguinal incision was performed on the femoral artery to create a hyaluronic acid embolism in the control and treatment groups (low-, medium-, and high-hyaluronidase groups). Hyaluronidase was injected subcutaneously. Photographic follow-up, histologic analysis, and quantification of hyaluronic acid were performed. Kruskal-Wallis test and post hoc with Bonferroni correction (p < 0.05) was used to compare the presence of hyaluronic acid in the arterial lumen between groups.

RESULTS

Despite the persistence of intravascular hyaluronic acid, macroscopic and microscopic differences were found between the embolism control group and embolism hyaluronidase high-dose group. Histologic analysis demonstrated thrombosis throughout groups. Skeletal muscle was least affected in the embolism hyaluronidase 500 IU group with less lysis and inflammatory infiltrate.

CONCLUSIONS

A 500 IU hyaluronidase dose partially prevents the damage caused by the embolism, and does not affect the surrounding tissue. The use of thrombolytic therapy combined with higher doses of hyaluronidase subcutaneously in this model is proposed.

Complications of Nonpermanent Facial Fillers: A Systematic Review

Background:

A variety of complications after injection of nonpermanent fillers for facial rejuvenation have been reported so far. However, to date, the overall complication rate is still a matter of debate. The aim of this study was to perform a systematic review of literature to assess the type and severity of associated complications following injections in different anatomical regions of the face.

Methods:

The entire PubMed/Medline database was screened to identify case reports and clinical studies describing complications that have occurred after injection of nonpermanent fillers in the face. These complications have been reviewed and analyzed according to their occurrence in different anatomical regions of the face.

Results:

Forty-six articles including a total of 164 patients reported on a total of 436 complications during the time period between January 2003 and February 2020. The majority of the complications were reported after injections to the nose and the nasolabial fold (n = 230), the forehead and the eyebrows (n = 53), and the glabellar region (n = 36). Out of 436 complications, 163 have been classified as severe or permanent including skin necrosis (n = 46), loss of vision (n = 35), or encephalitis (n = 1), whereas 273 complications were classified as mild or transient, such as local edema (n = 74), skin erythema (n = 69), and filler migration (n = 2). The most severe complications were observed in treatments of nose, glabella, and forehead.

Conclusions:

Nonpermanent facial fillers are associated with rare but potentially severe complications. Severity and impact of complications depend on the anatomical region of the face and eventually require profound knowledge of facial anatomy.

Early Intervention with Autologous Fat Grafting to Reduce Hypertrophic Scar Formation: A Prelimilary Study

BACKGROUND

Once an early-stage immature scar develops into a hypertrophic scar, it is difficult to achieve satisfactory improvement with existing treatments. Therefore, the prevention of hypertrophic scar formation should be given priority. Fat grafting was previously proven to be an effective treatment for mature scars, but it has not been used in the early-stages of (less than three months) scar formation.

OBJECTIVES

We present our experience with the use of combined grafting of macro fat and emulsified fat for prevention of hypertrophic scar formation in patients.

METHODS

Thirty-five patients who received fat grafting for facial scar repair were included as a treatment group and another 35 patients without particular interventions were classified as the control group. Patients in both groups were followed up every three months during one year, and the Vancouver Scar Scale (VSS) was used for evaluation of the clinical outcomes at baseline (within one to three months after trauma, burn or surgery) and after 12 months of follow-up.

RESULTS

All patients in the treatment group achieved a marked improvement after their first fat grafting procedure. Thirteen patients (37.1%) underwent the second procedure and seven (20%) underwent the third procedure. Statistical analysis of average VSS score also showed significant differences between the treatment and control groups.

CONCLUSION

The results of this retrospective study suggest that treatment of immature scars with combined grafting of macro fat and emulsified fat can successfully prevent the formation of hypertrophic scars.

LEVEL OF EVIDENCE III

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 .

The Course of the Angular Artery in the Midface: Implications for Surgical and Minimally Invasive Procedures

BACKGROUND

Previous anatomic studies have provided valuable information on the 2-dimensional course of the angular segment of the facial artery in the midface and its arterial connections. The third dimension (ie, the depth of the artery) is less well characterized.

OBJECTIVES

The objective of the present study was to describe the 3-dimensional pathway of the angular segment of the facial artery and its relationship to the muscles of facial expression.

METHODS

The bilateral location and the depth of the midfacial segment of the facial artery was measured utilizing multi-planar computed tomographic image analyses obtained from contrast agent-enhanced cranial computed tomographic scans of 156 Caucasians aged a of 45.19 ± 18.7 years and with a mean body mass index of 25.05 ± 4.9 kg/m2.

RESULTS

At the nasal ala, the mean depth of the main arterial trunk was 13.7 ± 3.7 mm (range, 2.7-25.0 mm), whereas at the medial canthus it was 1.02 ± 0.62 mm (range, 1.0-3.0 mm). This was reflected by the arteries' relationship to the midfacial muscles: at the nasal ala superficial to levator anguli oris in 62.0% but deep to the levator labii superioris alaeque nasi in 53.6%; at the medial canthus superficial to the levator labii superioris alaeque nasi in 83.1% and superficial to the orbicularis oculi in 82.7%.

CONCLUSIONS

The results presented herein confirm the high variability in the course of the angular segment of the facial artery. Various arterial pathways have been identified providing evidence that, in the midface, there is no guaranteed safe location for minimally invasive procedures.

Complications and Adverse Effects of Periocular Aesthetic Treatments

The popularity and variety of temporary and permanent periocular aesthetic treatments has increased over the past decade. Patients frequently present to eye clinics with ocular complications and side effects following these treatments, their severity ranging from ocular irritation from dry eyes to visual loss from vascular occlusion. A careful, thorough history is essential, as many patients may not associate aesthetic procedures with ocular complications, and some may be embarrassed to disclose this information. All ophthalmologists should understand the potential ocular sequelae of these treatments and be able to initiate treatment in sight-threatening cases. Wesummarises the current literature on ophthalmic complications of the most common periocular aesthetic treatments.

Superselective Arterial Hyaluronidase Thrombolysis Is Not an Effective Treatment for Hyaluronic Acid-Induced Retinal Artery Occlusion: Study in a Rabbit Model

BACKGROUND

Worldwide application of hyaluronic acid has brought about severe complications, including central retinal arterial occlusion, which leads to a deleterious effect on vision. The current study explored the efficacy of superselective arterial hyaluronidase thrombolysis in rabbit retinal artery occlusion induced by hyaluronic acid.

METHODS

Occlusion of the internal/external ophthalmic artery in New Zealand White rabbits was induced with superselective injection of hyaluronic acid. Superselective subtraction angiography and fundus examination were conducted to confirm and evaluate the artery embolism. After 30 minutes of embolism, hyaluronidase was injected in the occluded artery through superselective arterial intubation.

RESULTS

Compared with preoperative and contralateral eyes, the postoperative eyes showed the symptoms of central retinal arterial occlusion and embolization, confirmed by digital subtraction angiography. After intraarterial hyaluronidase thrombolysis, the embolization failed to dissolve as shown on funduscopic and angiographic examinations.

CONCLUSIONS

Superselective ophthalmic artery intervention could accurately and successfully establish the animal models of retinal artery occlusion induced by hyaluronic acid. The precise occlusion site of the retinal artery and complete embolism were confirmed by ophthalmologic examinations. Intraarterial hyaluronidase thrombolysis might not be an effective method to treat retinal artery occlusion induced by hyaluronic acid.

Generation of Filler Emboli as a Mechanism for Filler-Related Blindness

BACKGROUND

Intra-arterial injection of fillers can lead to occlusion of the ophthalmic artery or its branches supplying the retina or the optic nerve. The mechanism through which this occurs is incompletely understood. We investigated the possibility of generating microparticles after injecting commercially available fillers into a flowing system in vitro.

METHODS

Three hyaluronic acid fillers and one calcium hydroxylapatite filler were injected into an artificial saline flow system mimicking arterial systolic blood pressure and corresponding to the diameter of the facial artery. All the saline at the end of the tube was collected, centrifuged, and inspected for filler particles.

RESULTS

After injection into the system, all fillers immediately disintegrated into small particles that were carried downstream with the flow of the saline. The saline at the end of the tube contained collections of filler.

CONCLUSION

Hyaluronic acid and hydroxylapatite fillers break up into small particles immediately after injection into a flowing system, generating emboli rather than a column of filler. The results of this study lead us to hypothesize another potential mechanism leading to filler-related blindness.