Michael G. Brandt, Maha Al Gilani, Janet Balderston, Ross Davidson, Corey C. Moore, S. Mark Taylor. Microbiologic Assessment of Multidose Restylane for Facial Augmentation. Arch Facial Plast Surg. 2009;11(4):271–273. doi:10.1001/archfacial.2009.31
Since 1996, Restylane (Q-Med AB, Uppsala, Sweden; distributed by Medicis Aesthetics Canada, Toronto, Ontario), a nonanimal stabilized hyaluronic acid (NASHA), has been used as a soft-tissue filler in Europe and Canada and, more recently, the United States. The longstanding safety, efficacy, and low immunogenicity profile of Restylane and the other NASHA fillers have made them the preferred choice for facial soft-tissue augmentation.1- 5 Restylane is provided in prefilled 0.5-mL and 1.0-mL single-dose syringes. Although the manufacturer does not recommend its use as a multidose syringe, based largely on the cost of the product, it has been our practice to save any unused portion of the prefilled syringe for future dosing in the same patient. This practice has been well received by patients because they occasionally require a repeated injection after 2 weeks to achieve their desired result. Although the safety of this multidose practice has been reported in the literature,5,6 patients and physicians alike remain concerned about the potential for bacterial infection with repeated dosing. Based on this concern, the objective of this study was to perform a comprehensive microbiologic assessment of multidose Restylane for facial augmentation. In doing so, we sought to specifically determine whether the product itself, or the product plus its original syringe, could become contaminated. As a unique experiment, this study went on to explore whether Restylane itself could serve as a culture medium for a common cutaneous microorganism.
All Restylane product used was within the manufacturer-suggested expiration date. Because this study was a comprehensive microbiologic review not requiring patient intervention, no institutional ethics review approval was attained. All patients were treated as per current standards of care, and preinjection informed consent was attained.
Patients were injected with Restylane, 1.0 mL, a gel that consists of NASHA, 20 mg/mL, dispersed in a physiological isotonic sodium chloride solution (pH, 7.0). The transparent, viscous gel is supplied in a disposable 1.0-mL glass syringe with a sterilized 30-gauge, 0.5-inch needle for intradermal injection.
Injection for both rhytids and lip augmentation was performed using a sterile technique. The injection site was cleansed with a sterile, 70% isopropyl alcohol wipe. The sterile Restylane product was removed from its packaging in a sterile fashion. The sterile needle cap was removed from the syringe and held by an assistant wearing sterile gloves during each injection. Sterile gloves were worn by the single injecting physician (the senior author, M.T.), and the injections were performed using a linear threading technique with the injected volume being dependent on the subjectively observed depth of the soft-tissue defect to be corrected or the subjective level of fullness observed in the lips. Immediately following injection, the syringe needle was recapped by the senior author, who took care to prevent contact of the needle with the walls of the syringe cap. Any remaining Restylane product was then stored vertically, tip down, at room temperature in a locked cabinet used exclusively for the purposes of this study. Prior to storage, and using an aseptic technique, approximately half of the needles (with their corresponding needle caps) were removed and replaced with a fresh sterile 30-gauge needle.
A total of 30 syringes were saved following injection of Restylane into 1 of 3 anatomical sites as follows: lip, 22 patients (73%); marionette lines, 2 (7%); and nasolabial folds, 6 (20%). Restylane was injected into the lips for the purposes of lip augmentation and into the nasolabial folds and marionette lines for the correction of dermal rhytids. The first 14 syringes maintained their original used needle. The subsequent 16 syringe needles were replaced as per the study protocol. The 30 syringes were then saved for 1 to 87 days prior to transport to the laboratory to be cultured (Table).
The culture technique was supervised by a microbiologist (R.D.) and was identical for both syringes containing used and new needles. Aseptically, 0.5 mL of thioglycolate broth was drawn into the barrel of the syringe and reexpressed into 10 mL of thioglycolate broth. The broth was incubated at 35°C for 72 hours in ambient air. At 24-hour intervals, the broth was examined for evidence of turbidity. When bacterial growth was suspected, 0.5 mL of broth was aseptically removed and plated onto sheep blood agar (5%) and chocolate agar. Bacterial growth was identified using standard methods. All thioglycolate broths were blindly cultured at 72 hours.
For the final aspect of the experiment, 2 syringes of Restylane were seeded with 102 and 105 colony forming units (CFUs) per milliliter of Staphylococcus epidermidis, respectively. Aliquots were removed at 0, 2, 6, 12, and 24 hours. Aliquots were cultured on 5% sheep blood agar, and viable colonies were counted using standard microbiologic techniques.
Of cultures from the 30 stored syringes, 28 (93.3%) yielded no bacterial growth (Table). Of cultures in the vials in which the original needle was left on the syringe, 12 of 14 (86%) yielded no bacterial growth. Both of the vials that yielded organisms had been used for lip augmentation. The cultures of positive vials were consistent with oral flora, including S epidermis, Staphylococcus oralis, and diphtheroids. The remaining 16 vials, which had the needles changed immediately after injection, were all negative for bacterial growth. Restylane vials containing the original needles were stored for a mean period of 49.86 days (95% confidence interval [CI], 32.27-67.45), and vials containing replaced needles were stored for 59.94 days (95% CI, 51.28-68.60). There were no statistically significant differences observed between the 2 groups based on storage duration (P = .33).
In the vial seeded with S epidermidis, 102 CFUs/mL, no bacteria were recovered after 6 hours. In the vial seeded with S epidermidis, 105 CFUs/mL, the bacterial count notably decreased over the 24-hour time frame, and the final count at 24 hours was 60 CFUs/mL.
Restylane has been shown to be successful for both lip augmentation and in the correction of facial rhytids. Although some patients require the entire contents of the 0.5-mL or 1.0-mL prefilled Restylane syringe, many do not. Based on manufacturer guidelines, it is suggested that any product remaining following injection be discarded. The generated waste of viable product and its initial expense suggest practical and economic benefits for the use of single-syringe multiple dosing. The results of this study fit well with those of previous reports.5,6 Used needle tips remaining on administered Restylane syringes resulted in positive bacterial cultures in 2 of 14 syringes (14%). Replacement of used needle tips with new sterile needles prior to storage of previously dosed Restylane syringes resulted in the absence of bacterial growth at up to 81 days. Finally, and as a novel experiment, the results of this study empirically demonstrate the inability of Restylane to serve as a bacterial culture medium.
Although the limitations of this study stem from a relatively small sample size and the longest duration of Restylane storage of approximately 3 months, previous reports using slightly larger samples6 and a longer duration of observation5 have demonstrated consistent results. An additional report7 investigating bacterial contamination among partially injected, prefilled collagen syringes reported cultures that yielded bacteria only in those syringes stored with used needle tips. Thus, it seems that remaining Restylane can be stored at room temperature for up to 9 months or its suggested expiration date (whichever is earlier), as long as the used needle tip is removed and replaced with a sterile substitute.
Thus, the failure of Restylane to serve as a culture medium and the absence of bacterial cultures among previously dosed syringes with the sterile replacement of used needle tips strongly suggest the microbiologic safety of Restylane as a multidose injection.
Correspondence: Dr Taylor, Division of Otolaryngology, Department of Surgery, Dalhousie University, Third Floor, Dickson Building, VG Site, Queen Elizabeth II Health Sciences Centre, 5820 University Ave, Halifax, NS B3H 2Y9, Canada (firstname.lastname@example.org).
Author Contributions:Study concept and design: Balderston, Davidson, Moore, and Taylor. Acquisition of data: Balderston, Moore, and Taylor. Analysis and interpretation of data: Brandt, Gilani, Balderston, Davidson, Moore, and Taylor. Drafting of the manuscript: Brandt, Gilani, Balderston, Davidson, Moore, and Taylor. Critical revision of the manuscript for important intellectual content: Brandt, Moore, and Taylor. Statistical analysis: Brandt, Gilani, Moore, and Taylor. Obtained funding: Moore and Taylor. Administrative, technical, and material support: Brandt, Balderston, Davidson, Moore, and Taylor. Study supervision: Davidson, Moore, and Taylor.
Financial Disclosure: None reported.
Previous Presentation: This study was presented at the 2006 Annual Meeting of the American Academy of Facial Plastic Surgery; September 14, 2006; Toronto, Ontario, Canada
This article was corrected online for typographical errors on October 1, 2010.