Background: The permanent filler polyacrylamide hydrogel (Aquamid) has been used for soft-tissue augmentation for more than 16 years. To evaluate the safety and efficacy of the material, the manufacturer initiated in 2001 a prospective clinical trial with a follow-up of 5 years. This represents one of the longest running studies on currently used fillers.
Methods: Two hundred fifty-one patients were enrolled in a noncomparative, prospective study and followed at 15 sites in Europe. The follow-up rates were 228 (90.8 percent), 101 (40.2 percent), 81 (32.3 percent), and 116 (46.2 percent) for the 12-, 24-, 36/48-, and 60-month follow-up periods. Patients received an average of 4.3 ml of Aquamid during an average of 2.4 injection sessions. Preferred areas were the nasolabial folds (37 percent) and the lips (28 percent). Study parameters were cosmetic outcome, blood analysis, and recording of local or generalized symptoms, including adverse reactions.
Results: Aesthetic outcome was rated as "very good" or "good" by 96.5 percent of patients and by 96.0 percent of investigators at final available follow-up. During the entire study period, a total of 53 adverse events and two serious adverse events were classified as treatment related. Thirteen adverse events were gel indurations and four cases of infection were seen. All had been resolved within the study period.
Conclusions: The study showed a very good aesthetic outcome and few adverse events after injection of polyacrylamide gel for soft-tissue augmentation. Correct application was essential to ensure a favorable result. For patients who desire facial soft-tissue augmentation, Aquamid is an excellent alternative to surgery.