I

Volume Replacement

Although we will describe fillers for deep level volumetric correction, changing the presentation of the product and the level of application allows its use for the intermediate level of correction.

Filling in the convex and concave areas of the face, which reflect light and shadows, can lead to a notable rejuvenating effect. The volume replacement is usually performed with fillers, implants or autologus fat. Prior to the advent of modern soft tissue fillers, the anatomical changes of the aging face were primarily surgically addressed (rhytidectomy, brow lift and mid-facelift) or by using ablative (carbon dioxide, CO ₂ ) lasers or peelings (fenol). Although these more invasive techniques are associated with an increased morbidity (infection, bleeding and increased downtime), they are still valuable tools in the cosmetic surgeon’s armamentarium for advanced facial antiaging. Combination therapies using soft tissue fillers, chemo-denervation, non-ablative laser and light sources provide a more appealing option to patients and surgeons, and can address many of the mild to moderate signs of aging.

There are many classifications of fillers, but they can be categorized based on their source as follows:

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  autogenic: fat (see Chapter 10 ), autologous plasma (see Chapter 13 ), autologous collagen (see Chapter 9 )

  
  
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  allogenic: cadaveric collagen, human fibroblast cell culture

  
  
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  xenogenic: collagen, mostly from bovine or porcine sources, and hyaluronic acid products from rooster combs or bacterial fermentation

  
  
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  synthetic: silicone products, polymethylmethacrylate (PMMA), hydroxylapatite, poly- l -lactic acid, polyacrylamide.

They can also be classified according to their durability after being injected in biodegradables and non-biodegradables (see Chapter 9 ). Some authors classify them according to their fibroblastic properties (poly- l -lactic acid, hydroxylapatite and, in a lower scale, hyaluronic acid fillers) if they are just passive fillers (collagen) or if they are permanent (silicone, PMMA). Pathologists do not always agree with this classification because it is their belief that every time a foreign body is introduced into the dermis it causes some degree of inflammatory reaction. That reaction can be mild or almost imperceptible (e.g. collagen) or moderate, with consequent fibroblastic activity associated (e.g. poly- l -lactic acid, hydroxylapatite or hyaluronic acid) or severe inflammatory response, generally related to clinical problems such as foreign body granulomatous reaction or even true troublesome tuberculoid granulomas.

II

Skin Tightening

The development of CO ₂ lasers demonstrated that heat can promote long-term collagen remodeling. Because of the long healing time and since patient selection is limited to fair skin types, the technology had to develop in another direction. The advent of radiofrequency (RF) technology opened up a new path for skin tightening without epidermal damage.

Radiofrequency energy is different from optical energy because it depends on the electrical properties of the skin, rather than on the levels of pigmentation, for the selective thermal destruction of targeted areas, which is known as electro-thermolysis. In 2004 the FDA approved RF dermal heating with simultaneous epidermal cooling as a tool to stimulate new collagen formation and, consequently, improve skin laxity. Thermage® (Thermage Inc., CA) was the first RF device launched, and today many devices promise to tighten the skin in a non-ablative way.

Systems using RF current alone, have achieved good results for skin tightening, with comparable efficacy to laser resurfacing and potentially more rapid healing. However, because of the high depth of penetration, the procedure can be more painful. A technology that integrates RF energy with optical energy – using a lower intensity of both – has also shown efficacy in hair removal and wrinkle reduction for all hair colors and skin types. In addition, these dual systems may reduce the risk of the side effects associated with either RF or optical treatments alone.

RF technology, using high frequency current in the range of 0.3 to 10 megahertz (MHz), produces a pure thermal effect on biological tissue that has made it useful for both electrosurgery and various dermatologic applications. Electrical conductivity relies on the frequency of electrical current, and the type and temperature of tissue. The distribution of electrical current depends on how the electrodes are configured. Typical configurations used in medicine are unipolar and bipolar. Although they differ in the way the RF current is controlled and directed at the target tissue, there is no difference in the final tissue effect at the same RF frequency.

One of the problems with RF technology is that some of the devices do not produce enough heat to cause collagen remodeling. Achieving a true skin-tightening effect in the dermal level (1 to 3 mm under the surface) requires a sustained volumetric dermal heating in one area, for a prescribed amount of time, without exposing fat, cartilage and nerves to residual heat. Inappropriate use of RF can paradoxically reduce fat in that area.

Another FDA-approved RF device for treating wrinkles and rhytids is the Accent XL® (Alma Lasers, Caesarea, Israel). It combines two RF modes in a single device. Each proprietary mode – bipolar and unipolar – is delivered by a discrete handpiece to distribute therapeutic heat at different tissue depths within the body. The bipolar handpiece creates local, superficial dermal heating on delicate areas, such as the face. The unipolar and larger handpieces provide deep dermal and subdermal heating of larger areas.

The latest application, currently in the final 544 Investigational Protocol FDA process, is able to penetrate to a depth of 100 mm. This device, the Lipotron® (RevecoMED International, Anaheim, CA), unlike its predecessors, will be used not only for wrinkle reduction, rejuvenation of the face and cellulite smoothing, but also for body contouring. The most significant feature of the Lipotron®, with its depth of heat penetration, is that it affects the visceral fat as well as the subcutaneous fat. It operates at 0.5 MHz and feels like a warm massage to the patient.

Other modalities, such as infrared devices (Titan®, Cutera Inc., CA) and ST Near Infrared handpiece (Alma Laser, Caesarea, Israel) are being used worldwide with a high level of patient satisfaction and few reports of collateral effects. Good candidates for these procedures are patients with light to moderate laxity, hidden mandibular arch, submental laxity, prominent nasolabial fold due to skin laxity and suborbicularis oculi fat (SOOF) pad descend (more than due to dermal atrophy), ptosis of eyebrow secondary to skin laxity of the upper third of the face, and thin skin, with little or no subcutaneous fat deposit, below the targeted area.

When using skin-tightening devices, perhaps the most critical point is making sure that the patient has realistic expectations of the limited potential of these non-invasive techniques. They should understand that they will not achieve the same results as with plastic surgery but they will have less risk, no scars or recovery time, and no interruption of their social or work activities. The key is to identify the critical areas that will elicit a pull or a lifting effect, distally to the vector force of the areas, and treat them in the same direction as in a facelift. Some practitioners even re-treat the area with multiple passes over the ‘anchoring points’ along the frontal hairline, zygomatic bone and pre auricular sulcus areas or any area where the skin is barely movable over the deep structures.

III

Muscle Relaxation and Facial Balance

Botulinum toxin injection is the most widely performed non-invasive procedure. It is the ‘gold standard’ treatment, especially for the upper third of the face. Botulinum toxin type A is a protein complex that is produced by the bacterium Clostridium botulinum , a powerful neurotoxin that causes muscle paralysis. In a medical setting, small doses of an injectable form of sterile, purified botulinum toxin are used to block the release of acetylcholine, which signals muscle contractions in the face. By selectively blocking the muscles’ ability to contract, botulinum toxin can soften the vertical frown lines between the eyebrows (glabellar lines) that tend to make individuals look tired, angry or old.

In 1989, the FDA approved botulinum toxin type A (Botox®) to treat two eye muscle disorders: blepharospasm (uncontrollable blinking) and strabismus (misaligned eyes). The toxin was subsequently approved to treat certain types of dystonia, a neurological disorder that causes severe contractions of the muscles, and hyperhidrosis, severe sweating of the armpits. During the course of these treatments, physicians noticed that Botox® softened the glabellar lines. In April 2002, after placebo-controlled, multicenter, randomized clinical studies demonstrated that botulinum toxin markedly improved these frown lines, the FDA approved Botox® for cosmetic use to temporarily improve the appearance of moderate to severe glabellar lines.

The cosmetic uses of the botulinum toxin are thoroughly discussed in Chapter 8 .

IV

The Surgical Approach

Although it is not the intention of this book to discuss surgical alternatives, the surgical approach has also changed dramatically because of the evolution and awareness of the physiology of the skin and the aging process. For many years, the classic surgical facelift with large incisions – eye, neck and brow lifts, bi-coronal pre- and retroauricular incisions – has been the only option for treating wrinkles associated with the skin’s loss of elasticity. Society’s growing interest in maintaining a youthful appearance has resulted in a greater awareness of the physiology of the skin and how to treat it in a more efficient way. Consequently, the incision size has decreased, sutures can be more effectively placed and the endoscopic approach is a reality. For periocular rejuvenation, the gold standard surgical approach is the transcutaneous approach to the upper lids and transconjunctival for the lower lids (CO ₂ laser-assisted or not) combined with resurfacing techniques (ablative, fractional lasers or chemical peels). The need for plastic surgery still exists, but non-invasive alternatives can complement surgery and often allow the patient to postpone surgery and bring longer-lasting results.