RESUMO
BACKGROUND: Correction of aging changes and contour deformities has been addressed largely by tissue augmentation agents whose volume is injected into tissues to achieve the required result. Polylactic acid (PLA) is an agent that is injected with the aim of enhancing the host's own collagen deposition. OBJECTIVE: We describe the development of multiple nodules and one case of a foreign-body granuloma formation following the administration of PLA to the face for correction of rhytides and contour deformities. Methods Four case presentations, including clinical history, injection protocol, histopathology, individual treatment, and their outcomes, are discussed with pertinent literature review. RESULTS: Four patients who received injections of PLA developed nodules that were clinically similar in size, shape, and consistency. Histopathologic examination revealed the presence of a foreign-body granulomatous inflammatory reaction in one of the patients. CONCLUSION: Cosmetic treatment with PLA may be complicated by disfiguring nodules that may mask a granulomatous reaction. PLA-induced nodules and foreign-body granulomas have proven difficult to treat. Therefore, PLA should only be injected in the infraorbital area by experienced injectors who have had appropriate training. In addition to this, PLA should be injected in a "depot" method below the muscle at a significantly diluted volume. Due to the complications encountered after the use of PLA, we feel that a cautionary warning regarding the use of PLA in this area may be prudent regardless of the abovementioned precautions.
