Lymphspiration: Contractility of Thoracic Duct - What Do We Know and What is Still to Be Discovered?

Recently, increased interest has focused on the phenomenon of lymphatic contractility. The thoracic duct and other lymph vessels appear to contract spontaneously to facilitate lymph flow with rate of contractions and their amplitude variable and dependent on different factors including fluid, concentration of ions or acidity, aging, drugs, or pathology. Not every lymph vessel remains contracting continuously with some seeming to completely stop their contractions due to various reasons. This may occur with no lymph flow within the vessel, or with very high flow, or it may be due to pathology or completely physiological conditions. Numerous studies have been conducted on this topic; however, their results may some-times seem contradictory. In this review, up-to-date publications have been collected and summarized to provide insights into the challenging topic of spontaneous lymphatic contractility and factors affecting it. This area remains of high research interest and newer techniques such as sonography may help to continue to shed light on the phenomenon of lymphatic contractility.