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Liquid Injectable Silicone for the Upper Third of the Face
Derek H. Jones
Liquid injectable silicone (LIS) is the most permanent of all injectable llers employed within the United States. For certain soft tissue defects, pure liquid silicone may be superior to other currently available filling
agents in properly selected patients.
LIS is controversial, with both advocates and opponents citing anecdotal data to support their position.1–6 Advocates of LIS rely on a wealth of anecdotal data to assert that it is safe and effective if the following three rules are strictly followed:
Rule 1 : Inject only pure medical grade, highly purified LIS that is intended for injection into the human body and specifically FDA approved for that purpose. To date, two LIS products are FDA approved: Silikon 1000 (Alcon Labs, Fort Worth, TX) and Adatosil 5000 (Bausch and Lomb, Rochester, NY). Both were FDA approved in the mid-1990s for intraocular injection to treat retinal detachment. Under new guidelines enacted under the 1997 FDA Modernization Act, these medical devices may be legally injected off-label for any indication deemed appropriate within a unique physician–patient relationship. Of the two FDA-approved silicone oils, Silikon 1000 is a less viscous substance and is more appropriate for injection through smaller-gauge needles, making it the more appropriate substance for tissue augmentation. It should be noted that prior to 1990, there was no FDA-approved LIS. Most LIS prior to 1990 was obtained from clandestine sources. Studies have proven that most of those products contained impurities that adversely affected biocompatibility.7 Injection of such products prior to 1990 was extremely common, with publicity surrounding associated adverse events leading to a negative public image.5
Rule 2: Adhere to strict microdroplet, serial puncture technique. This is defined as injection of 0.01 cc strictly into the subdermal plane at 2- to
5-mm intervals, through a 27-gauge metal hub needle or smaller, with no double pass over a given area at any one visit. Intradermal injection should be avoided, as dermal nodules may result. Over time (1–3 months), a limited foreign body response produces a collagenous
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Chapter 121 Liquid Injectable Silicone for the Upper Third of the Face 365
capsule around each microdroplet, anchoring it in place and further enhancing tissue augmentation.
Rule 3 : Inject small volumes at monthly intervals. Optimal correction occurs slowly over time. LIS is an oil and injected in large bolus may track along tissue planes, which gives silicone a reputation for migration. However, potential for drift is eliminated as long as small volumes are injected at monthly intervals utilizing microdroplet, serial puncture technique.
Histologic analysis of purified liquid silicone present in vivo for long periods (up to 38 years) displays impressive biocompatibility.4 Despite rigid adherence to these rules, adverse events may rarely occur, even years after injection.5 The most worrisome complication is granuloma formation, which clinically may appear as a firm or even rock-hard nodule in the skin. The overlying skin may reflect edema and purple, red, or brown discoloration. Such adverse events may be treated with injection of intralesional steroids and the oral antibiotic minocycline. In ammatory adverse events have been noted to arise in conjunction with an adjacent infection, such as a sinus infection or a dental abscess. Surgical correction may be required.
For the upper third of the face, LIS may be employed for the following indications:
1.Acne scarring3
2.Deep glabellar furrow.
3.Temporal lipoatrophy associated with HIV2
The specific technique for each of these indications iswell described in the references. The reader should be cautioned that LIS, although extraordinarily useful as a permanent injectable filler, is the least forgiving of all filling agents. Physicians wishing to perform this procedure should receive appropriate training. Furthermore, different liability carriers have varied regulation regarding off-label use of LIS. In the author’s opinion, until longer term studies are available with the currently available FDA-approved silicone oils, LIS should be reserved for severe atrophic acne scarring and severe HIV facial lipoatrophy, where other
llers may not work as well or be cost-effective.
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A
Figure 121.1. (A) HIV lipoatrophy pretreatment. (B) HIV facial lipoatrophy after a series of liquid injectable silicone to the cheeks, temples, and glabella. The glabella has also been treated with Botox.
Chapter 121 Liquid Injectable Silicone for the Upper Third of the Face 367
B
Figure 121.1. (Continued)
References
1.Orentreich DS, Jones DH. Liquid injectable silicone. In: Carruthers J, Carruthers A (ed.). Soft Tissue Augmentation. New York: Elsevier, 2005: 77–91.
2.Jones DH, Carruthers A, Orentreich D, et al. Highly purified 1000-cSt silicone oil for treatment of human immunodeficiency virus-associated facial lipoatrophy: an open pilot trial. Dermatol Surg 2004;30:1279–1286.
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3.Barnett JG, Barnett CR. Treatment of acne scars with liquid silicone injections: 30 year perspective. Dermatol Surg 2005;31:1542–1549.
4.Balkin SW. Injectable silicone and the foot: a 41-year clinical and histologic history. Dermatol Surg 2005;31:1555–1560.
5.Duffy DM. Liquid silicone for soft tissue augmentation. Dermatol Surg 2005; 31:1530–1541.
6.Rapaport MR. Silicone injections revisited. Dermatol Surg 2002;28:594–595.
7.Parel JM. Silicone oils: physiochemical properties. In: Glaser BM, Michels RG (eds.), Retina, Vol 3. St. Louis: Mosby, 1989:261–277.