Introduction

In the mid-1990s rumors began to spread in west Europe about successful major soft tissue reconstructions being performed in Russia with a permanent filler called Formacryl^®. Some physicians got interested and visited the clinics where the product was used, and returned confirming they had witnessed remarkable corrections of very large congenital and acquired defects. However, others also reported seeing significant complications.

An Italian company, at that time called Progen, imported a large amount of Formacryl^® from Russia in 1997, tested it and ‘modified’ it for increased safety (this is what they claimed at that time), then began to market it with the same name. Shortly afterwards the company’s name changed (to Polymekon), as did that of its product, which was re-named Bio-Formacryl^®. It was defined as a gel composed of 4% polyalkylamide and 96% water. The indications were for small- and large-volume soft tissue augmentations, for both aesthetic and reconstructive purposes. No maximum volumes were indicated by the manufacturers for injection.

Following further research to improve biocompatibility, of which the company never released any detail, the product was changed again in 2001, the new name being Bio-Alcamid^®. This was a non-biodegradable, biocompatible synthetic polymeric transparent gel with a reticulated structure derived from acrylic acid, containing 4% alkyl-amide-imide groups and 96% apyrogenic water (Fig. 12.1). In 2001, Bio-Alcamid^® obtained a Conformité Européenne (CE) certificate, the only requirement in Europe for approval of an injectable filler. It was produced in three different forms of increasing density, i.e. lips, face, and body. The indications remained the same as for Formacryl / Bio-Formacryl^®, and again no limits were established in terms of injectable volumes per patient. Bio-Alcamid^® correction of large-volume deficiencies such as those caused by pectus excavatum, Poland and Parry–Romberg syndromes and HIV drug-induced lipodystrophy quickly became popular. The patients tolerated the injections well and the clinical results seemed very satisfactory. The material was seen as a valid alternative to lipostructure because of the more predictable results that it offered. The reports in the early literature were extremely good (e.g. those by Pacini et al, Protopapa et al, Terenzi et al, and Casavantes).

Figure 12.1 Bio-Alcamid^®, before injection, is a dense, transparent gel.

Clinical use of Bio-Alcamid^®

Bio-Alcamid^® is quite easy to use. It flows smoothly through needles or cannulas of adequate size depending on the type of product used (i.e. lips, face or body), and should be injected in the subcutaneous tissue only, not in the dermis. It can be effectively molded with massage. Aseptic technique during application is mandatory as with all fillers, in particular with permanent products. Antibiotic prophylaxis may also be advisable, especially for large-volume implants.

Very little pain is experienced by the patient for small-volume corrections, providing the injection is performed slowly. The product itself has a pH of 7 and elicits no discomfort. Larger volumes can be significantly more painful owing to tissue expansion; in such cases pain control is advisable. There may be mild swelling and some redness for a few days, but these resolve promptly and spontaneously. After a short while, Bio-Alcamid^® is surrounded by a thin fibrous capsule. This particular property gave rise to the definition of ‘soft tissue endoprosthesis’.

The technique for small-volume implants is very similar to that for hyaluronic acid. For larger volumes, in earlier days a monocompartmental correction was suggested to minimize the number of percutaneous entries. Subsequently, multiple compartments were preferred because the capsule around each deposit helps shape stability over time. Care should be taken to discontinue pressure on the syringe well before exit from the skin of the needle or cannula tip to prevent Bio-Alcamid^® from coating the tissues at the entry port, because this could hamper wound healing and promote infection. Hydrogen peroxide is helpful to remove traces of the product from the percutaneous access in such cases. Staged corrections have also been advocated for very large defects for more precise results; however, the risk of contamination increases significantly with each session, and this potential sequela should carefully be considered.

By keeping the material in a closed chamber, another benefit of the capsule is the possibility of removing a desired amount of the product in case of overcorrection or dislocation. This is achieved by aspiration or by squeezing through a small stab incision.

Immediate results are very satisfactory in terms of shape and softness. Indeed, even very-large-volume defects can be corrected surprisingly well. This seems even more surprising when one thinks that these results could be achieved 10 years ago.

Complications of Bio-Alcamid^®

After the initial enthusiasm, distressing news soon began to surface because of significant complications. Unfortunately, these were not always reported promptly. The first reports in the literature began to appear soon after the product was released, and they have been rapidly increasing in number. A classification of this issue is not easy and should consider clinical, microbiological, and histological data together. The complications we describe are essentially based on our personal clinical observations, and different situations may well have been experienced by others.

Early acute reactions may arise just a few days after the implant. The area becomes swollen, red, and painful and in some cases fever may occur. Fluctuation may also be present. In such cases, it is reasonable to believe that bacterial contamination occurred at the time of application owing to technical inaccuracy; therefore, these events do not seem to be product related. As stated above, sterility during injections of fillers, especially permanent ones, is of the greatest importance but is unfortunately often overlooked.