Injectable Fillers and Facial Restoration
Mary Lynn Moran
INTRODUCTION
Injectable treatments have been used in the face since the late 1800s following the invention of the syringe. Among the first attempts was an injection of liquid paraffin into the lips, which was disastrous. In the 1950s, liquid silicone became a popular filler for the breasts and was subsequently used in the face. A combination of complications and legal concerns ultimately forced this practice underground. Modern use of injectables in the realm of facial restoration and rejuvenation dates back to the 1980s with the FDA approval of collagen fillers. Injectables have become an important and ever-growing segment of the facial rejuvenation industry over the last two decades.
The overall growth in minimally invasive procedures between 2000 and 2016 was 180% according to the National Clearinghouse of Plastic Surgery. Cosmetic injectable neurotoxin procedures experienced a 797% growth during that period. Seven million injectable procedures were performed in 2016. This is a result of many factors. Patients hope that new less invasive technologies will eventually replace traditional surgical treatments thereby obviating the need for longer recovery and greater expense, downtime, and discomfort. New technologies have to some degree fulfilled these desires. Another element adding to the enthusiasm of physicians for injectables is our deepening understanding of the dynamic volumetric nature of the aging face. As we gain more experience with fillers, we understand more fully how they can address many of the changes that contribute to a less than desirable facial balance. The safety and straightforward nature of fillers make them an ideal choice for many indications in the face.
HISTORY
Due to the variety of applications, and the relatively low-risk nature of the filler procedure, many individuals are good candidates for filler placement. The most important element of the history is to ascertain the patient’s goals. A thorough understanding of what the patient hopes to achieve should be established followed by an honest assessment by the physician of what he or she can realistically accomplish. Computer imaging is a very beneficial way of illustrating what can and cannot be achieved given the patient’s desired procedure, the patient’s budget, and the physician’s capabilities. Once mutual goals and understanding are reached, certain elements in the patient’s health history should be obtained. The patient’s history with previous filler injections can be very enlightening in terms of both alerting the surgeon to any undesirable reactions and the patient’s history of dealing with past disappointments. Preventative management is the best way to avoid risks. Risks for bleeding and bruising should be elicited such as a history of using anticoagulants or taking aspirin or NSAIDS. The patient with a history of perioral herpes simplex should be identified so that preventative measures can be initiated.
General health issues such as diabetes mellitus, collagen vascular diseases, or use of steroids or Accutane should also be noted. Any history of allergic reactions should be documented. If products with animal origins
(such as the bovine collagen used with PMMA) are being used, any history of allergies to animal products should be established. Skin tests should be done when appropriate. Cigarette smoking and active sun exposure should be noted. It is also important to establish the patient’s tolerance for bruising during the time that the patient plans to undergo treatment. If sensitive work or social events are imminent, it would be best to postpone the injections to a time when some bruising or swelling is more tolerable. Any recent facial procedures such as peels or other aesthetic treatments should be documented. Patients who are on antiretroviral therapy suffering from facial lipoatrophy will benefit from restorative fillers and were in fact the first FDA indication for fillers such as Sculptra. Patients who have congenital or acquired facial lipoatrophy also benefit greatly from fillers.
(such as the bovine collagen used with PMMA) are being used, any history of allergies to animal products should be established. Skin tests should be done when appropriate. Cigarette smoking and active sun exposure should be noted. It is also important to establish the patient’s tolerance for bruising during the time that the patient plans to undergo treatment. If sensitive work or social events are imminent, it would be best to postpone the injections to a time when some bruising or swelling is more tolerable. Any recent facial procedures such as peels or other aesthetic treatments should be documented. Patients who are on antiretroviral therapy suffering from facial lipoatrophy will benefit from restorative fillers and were in fact the first FDA indication for fillers such as Sculptra. Patients who have congenital or acquired facial lipoatrophy also benefit greatly from fillers.
PHYSICAL EXAMINATION
Examining the patient begins when the physician first meets the patient. The seasoned facial rejuvenation surgeon is always scanning facial features and assessing which ideal modifications may best serve the patient. Before the patient has expressed his or her goals, many facial surgeons have already established their own priorities. However, during the consultation, the patients should be allowed to expresses their concerns first. After carefully listening and obtaining all of the important information, the physician should then examine the patient. This is where the computer imager can be a vital tool to objectify the physicians’ observations and reflect back to the patient what he/she has just described. The physician has probably identified several other areas that could be addressed, but that the patient has not mentioned. If the physician senses that the patient is open to other suggestions, then this is an appropriate time for this discussion.
Physical findings to note are any scars from surgery, trauma, or acne. Evidence of active bacterial or viral infection, sunburn, or windburn should be discussed. Previous filler treatments, if visible, should be documented including visible Tyndall effects. Facial asymmetry needs to be documented photographically and discussed in detail with the patient. Assessment of skin type is important as different types react differently to trauma. In particular, patients with darker skin tend to have residual pigmentation after bruising that can be slow to resolve (e.g., periocular complex).
INDICATIONS
Fillers address facial changes due to a variety of causes. They can be used at nearly any depth and are being used more and more to replace lost underlying structural support. Aging causes loss of skin elasticity, weakening of ligamentous support, descent of adipose tissue, atrophy of adipose tissue, and loss of bone. These forces lead to sagging tissues and deepening creases. Essentially, the aging face is a series of shifting and shrinking vectors with a resultant cascading of soft tissue. Furthermore, repeated movement causes wrinkles, which can become quite deep. Understanding and identifying these changes is paramount in making effective improvements in the aging face. Fillers are very versatile tools to address many of these changes. They can support sagging or thinning skin, fill creases and folds, correct depressions, replace or enhance bone loss and deficiency, and replace loss of adipose tissue. The goal in treating the aging face is to restore youthful contours and facial balance.
Other conditions also respond well to treatment with filler. Atrophic or depressed scars from trauma and acne can be improved depending on the amount of tethering. Fillers can treat volume loss due to weight loss, excessive exercise, antiretroviral therapy, hemifacial atrophy, surgical removal of masses, or bony trauma.
Common treatment sites include
Fine and deep facial lines
Nasolabial folds
Lip lines
Lips (for enhancement and restoration)
Newer indications have come about as a result of greater understanding of the volumetric changes in the aging face. These include:
CONTRAINDICATIONS
Fillers should not be used in patients who have unrealistic expectations of what can be achieved with them. Specifically, they should be made aware of the fact that some indications require larger volumes of filler to achieve the desired result. Patients with significant lipoatrophy must be completely informed of the limitations in a chosen filler and the volume restoration that can be achieved. Elderly patients may not achieve the results hoped for by both physician and patient. It is wise with mature patients to focus on a specific limited treatment area that is most troublesome rather than attempt to achieve a great global rejuvenation.
If a patient treated elsewhere comes in already overfilled, it would be wise to discuss your observations with the patient in a tactful manner and suggest that he or she hold off on any further filler at this time. Computer imaging can also assist with this discussion. The physician can even offer reduction of the overcorrection with hyaluronidase if the filler is hyaluronic acid based. The possibility of body dysmorphic disorder should be considered, but many emotionally sound patients have fallen into the trap of not realizing the relative disproportion created by their filler treatment.
Patients who are intolerant of any bruising are not good candidates for injectable filler treatments. The likelihood of some amount of bruising during any given treatment session is high enough even in the most skilled hands that it should be considered an expected outcome.
General health concerns that would preclude using injectable fillers would apply to patients who are taking anticoagulants. In cases where anticoagulants can be discontinued prior to treatment, patients are likely to have less bruising. Patients who have active skin conditions such as rash, infection, sunburn, or herpetic outbreaks should not have this area treated until after the condition resolves. Patients who are diabetic or immunocompromised should only be treated if the physician treating their disorder clears them for the procedure. They should receive extra care during the preparation of the skin and counseled about postoperative treatment of the injection site. Patients with collagen vascular diseases should not receive collagen-based products such as polymethyl methacrylate (PMMA). Skin testing is required for most autologous collagen products, especially those of bovine origin. Clearly, any patient with a history of allergic reaction to collagen or a collagen skin test should not be considered a candidate for treatment with collagen-based products even if the reaction was in the past.
PREOPERATIVE PLANNING
Preprocedural planning begins during the consultation. Once treatment areas are identified and goals and outcomes are mutually understood, the physician should explain all of the risks to the patient and obtain a signed consent. If the patients have taken any common agents that contribute to bruising, they should be counseled that they may bruise more than average or perhaps be rescheduled. Photos should be taken of the entire face from five views as well as appropriate close-ups. Fees are thoroughly discussed in advance as are “touch-up” policies.
Filler Selection
The origins of our modern experience with fillers began with collagen. Zyplast and Zyderm were central elements in most facial rejuvenation practices. With the advent of hyaluronic acid fillers, market demand for collagen fillers diminished, and eventually production was terminated. Hyaluronic acid is a naturally occurring polysaccharide, and today’s most popular product is non-animal-derived stabilized hyaluronic acid (NASHA). Other popular injectable fillers include synthetic fillers made of calcium hydroxylapatite (CaHA) and poly-L-lactic acid (PLLA). Both are biostimulatory and therefore create new collagen. CaHA also has volume replacement action. Both are temporary (see Table 28.1 for a comparison of properties). A permanent synthetic filler is PMMA. Adipose tissue and medical-grade silicone are other injectables used in facial restoration but remain outside the scope of this chapter. Another very important category of facial injectables for facial rejuvenation includes the neurotoxin family. This chapter will focus only on injectable fillers.
The choice of injectable filler is based upon operator experience and preference, location and indication, safety concerns, reversibility, patient preference, and general health factors.
The general classification of fillers is divided into the following:
Volume replacement fillers versus biostimulatory fillers
Short versus long versus permanent duration
Naturally derived versus synthetic fillers
TABLE 28.1 Comparison of Properties | ||||||||||||||||||||||||
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Hyaluronic acid fillers dominate the marketplace due to the relative ease of use and low complication rate. They are also unique in that they are reversible with hyaluronidase. Hyaluronic acid is a highly hydrophilic molecule, which holds up to 2,000 times its own weight in water acting as a humectant. It is a natural, linear polysaccharide glycosaminoglycan with alternating residues of D-glucuronic acid and N-acetyl-D-glucosamine. It is a component of connective tissue in all mammals and so is not tissue or species specific, making it nonimmunogenic. It is found in skin extracellular matrix, synovial fluid, vitreous humor, and vocal cords, among many other locations in the human body. It exhibits isovolumetric degradation in which molecules of hyaluronic acid degrade, allowing those remaining to absorb more water. This allows the total volume of gel to remain stable over time. Currently available commercially derived hyaluronic acid is derived from strep bacterium and therefore is referred to as non-animal-derived stabilized hyaluronic acid (NASHA).
The importance of hyaluronic acid in the skin cannot be understated. Its ability to bind with water gives skin its volume and structural integrity. It interacts with intercellular lipids and regulates the mechanical properties of the stratum corneum. It maintains the viscoelasticity of the skin and its concentration diminishes with age.