Safety of Copolyamide Filler Injection for Breast Augmentation

Shunichi Nomoto, MD; Keiko Hirakawa, PhD; Rei Ogawa, MD, PhD, FACS


Plast Reconstr Surg Glob Open. 2021;9(2):e3296 

In This Article

Materials and Methods

Retrospective Cohort Study

This retrospective cohort study was conducted on all consecutive patients who had undergone breast augmentation injections with copolyamide fillers and who visited our hospital during the 27-month period between January 2018 and March 2020 due to injection sequelae or concerns. The age, sex, formulation that was used, the sequelae, and their treatment were extracted from the medical records.

NMR Analysis of Copolyamide and PAAG Fillers

The components of Aquafilling/Los Deline and Aqualift/Activegel were analyzed by NMR spectroscopy (the formulations actually tested bore the labels Los Deline and Aqualift). The data were processed by using Alice2 for windows, ver.6 (JEOL DATUM Ltd., Tokyo, Japan) and were compared with the existing data in our in-house NMR database for PAAG itself and 3 additional formulations of PAAG, namely, the Amazingel and Aquamid fillers and the precast polyacrylamide gel e-PAGEL HR that is used for electrophoresis (EHR-T 7.5L, ATTO Corporation, Japan). The NMR data of the latter 3 products and the 2 copolyamide fillers were all obtained with the same procedure. Thus, each product was injected into a 3.2-mm (outer diameter) sealing sample tube (JEOL Ltd., Tokyo, Japan), and Field Gradient Magic Angle Spinning (FGMAS) or solution-state NMR analyses were performed at a proton frequency of 500 MHz (11.7 tesla) using a JNM-ECZ500R (JEOL Ltd.) interfaced with a 3.2-m FGMAS probe at room temperature under the conditions shown in Table 1.