Facial fat grafting is increasing worldwide. Although there are few reports in the literature on complications following facial lipofilling, rare but serious complications include embolic risk to local end organs such as the skin and eye, and the central nervous system. Treatment strategies are outlined. The key to prevention of complications is understanding the regional anatomy. It is imperative to adhere to the safe and efficacious techniques to minimize risk. Every surgeon who performs facial fat grafting should establish a systematic method to deliver safe, consistent, and long-term results for their patients.
Facial fat grafting, in general, is considered a safe procedure with a very low complication rate.
Incidences of complications, especially some serious ones, are possibly underreported.
Prevention of complications relies on mastery of local anatomy and emphasis on safe techniques.
Complication management begins with high index of suspicion, early diagnosis, and prompt treatment.
Facial fat grafting has become a popular adjunct to facial rejuvenation, contouring, or regenerative surgery. However, as the prevalence of this procedure increases, the incidences of serious complications after facial fat grafting are also rising. This may be especially true with less experienced surgeons. As of this writing, the literature contains only on a handful of case reports. However, complications may be underreported and thus the incidence of more serious complications may be higher. Serious complications include infections and injury to important structures, such as the globe, as well as fat emboli into the brain. In this article, the authors review reported serious complications after facial fat grafting and provide their expert opinions on how those complications could potentially be prevented. Furthermore, proper management of each type of complication after facial fat grafting is outlined.
Reported serious complications
One of the largest retrospective series, by Kim and colleagues, reviewed 1261 patients who underwent full-face fat grafting for augmentation and found 62 patients (4.9%) who developed moderate complications. This included chronic swelling, fibrosis, acne, headaches, and irregularity after injection. They did not find any severe complications in their cohort.
However, there have been case reports and small case series that do highlight the severe complications that can occur following facial fat grafting. There have been no extensive reports of serious infections associated with facial fat grafting. However, the literature does contain reported cases of atypical mycobacterial infections following facial fat grafting. Interestingly, a report of atypical mycobacterial infection was found following rhytidectomy and neck lift, without fat grafting as an adjunct. More recently, there are reports of atypical mycobacterial infection following facial fat grafting with the use of cryopreserved autologous fat, as well as fresh autologous fat. Additionally, fat grafting was used as an adjunct to a transconjunctival lower blepharoplasty in 1 such case. All cases resolved with antibiotics, with or without additional surgical interventions, but the patients were left with contour irregularities, scarring, and hyperpigmentation.
However, there are small numbers of case reports that do highlight loss of vision, as well as cerebral infarct, as a rare complication. Early case reports by Teimourian, as well as Feinendegen a decade later, highlight such dreaded complications. In the former, immediate ocular pain and subsequent permanent vision loss was noted; whereas, in the latter, complications were seen 7 hours postinjection with both cerebral and retinal infarcts. The proposed mechanism is likely a combination of anatomy and technique. High pressure generated within a relatively small area can force particles of fat into the arterial arcade of the face. The pressure leads to retrograde flow within the arterial system, often from a terminal branch of the ophthalmic artery (ie, supratrochlear or dorsal nasal artery), which then can embolize to the central retinal artery or propel more centrally into the internal carotid artery. A 2012 systematic review found 15 reports of blindness following facial cosmetic fat grafting. In all cases, the signs and symptoms of an adverse effect were seen almost immediately. All patients complained of ocular pain and loss of vision, and 3 patients experienced additional central nervous system deficits resulting from cerebral infarct secondary to fat emboli. Although the data are incomplete, the review does highlight certain suboptimal techniques. These include use of 10 cm 3 and 20 cm 3 syringes for injection, as well as the use of sharp needles for injection. Tragically, there has been 1 case report of a fatal stroke following facial fat injection in the neurology literature.
Prevention of complications
The importance of prevention is paramount in avoiding serious complications following facial fat grafting. The keys to prevention are knowing the anatomy, appropriate recipient site preparation, and safe injection technique. The head and neck anatomy is arguably one of complexities and nuances. Knowing the key anatomy and landmarks is central in providing safety for the patient. There are several review articles that dive deeper into the regional anatomy of the upper, middle, and lower thirds of the face. Specific areas of interest include the temporal region, the periorbital, and the nasal region. A 2017 cadaveric study of the temporal region highlight 4 separate fat compartments as ideal targets for fat grafting. The investigators also define an anatomic danger zone of caution, which contains the sentinel vein, perforating vessels, and branches of the facial nerve ( Fig. 1 ). From this study, the investigators recommend a safe site of cannula insertion, as well as a technique to address the deep and superficial fat compartments.
Specific to the periorbital and perinasal anatomy, a recent 2018 meta-analysis found 48 new cases of filler-induced vision changes in a 3-year period. Only 1 case reported the use of autologous fat. The investigators found the most common location of injection that caused vision changes were in the nasal region (56%), followed by the glabella (27%), and forehead (18%). They highlight the local vascular anatomy and the importance of recognizing high-risk areas such as the glabella and perinasal region. Surgeons should be cautious of their injection plane, which is often safest on the bone or periosteum, or superficial in the dermis. Additionally, there are many variable vascular arcades in these regions that can all be put at risk for embolic events, especially if safe injection technique is not strictly adhered to. One of the most vulnerable periorbital vessels is the ophthalmic artery. It has many branches, including the supraorbital and supratrochlear arteries, as well as the dorsal nasal artery ( Fig. 2 ). Each of these superficial arteries can be injured during autologous lipofilling, thus acting as a retrograde channel to the ophthalmic artery via strong retrograde pressure-induced embolization.
The perinasal vasculature also has anastomosis with the previously mentioned branches from the ophthalmic artery. The facial artery and its terminal branches, such as the angular artery, also share anastomotic arcades with the supratrochlear and infraorbital arteries. Again, the safest location for injection is deep, on the bone or cartilage, or within the dermis. However, it is tempting to inject within the subcutaneous tissue plane, especially within stronger rhytides, such as the nasolabial fold, or to augment nasal shape and projection ( Fig. 3 ). However, the facial artery and its branches course within this region and thus are susceptible to cannulation or embolization, possibly accounting for why perinasal injections are responsible for most complications seen in a recent review. In the worst case scenario, overfilling and the subsequent pressure gradient can lead to even more proximal embolic phenomenon within the internal carotid artery and, therefore, into the central nervous system.