The reconstruction of large-volume soft tissue defects is a major problem in plastic surgery. Many plastic surgeons have focused on external volume expansion (EVE) because of its capacity to promote regeneration of soft tissues, including breast, subcutaneous fat, and skin. EVE is a minimally invasive and less costly tissue engineering approach that has shown great clinical potential. However, many challenges still need to be addressed before such technology can become a common clinical practice. Basic in vivo and in vitro studies have been performed to determine the possible mechanisms by which EVE promotes tissue regeneration and to design optimized animal models. EVE application was found to facilitate cell proliferation and migration, enhance adipogenesis, improve angiogenesis, and provide available space for soft tissue growth. Understanding the mechanical and chemical signals associated with EVE during tissue regeneration may enable the clinical adaptation of this technology. This article reviews the clinical application of EVE techniques, describes preclinical animal models, and evaluates the possible mechanisms by which EVE induces tissue regeneration. Impact statement The reconstruction of large-volume soft tissue defects is a major problem in plastic surgery. External volume expansion (EVE) is a minimally invasive and less costly tissue engineering approach that has shown promise in clinical applications. This article reviews the clinical application of EVE techniques, describes preclinical animal models, and evaluates the possible mechanisms by which EVE induces tissue regeneration.
Keywords: adipogenesis; adipose regeneration; angiogenesis; cell migration; cell proliferation; external volume expansion.