Definition

A sterile solution of a nontoxic tricarbocyanine dye with a peak spectral absorption at 790 nm, with application in determining cardiac output, hepatic function, liver blood flow, as well as ophthalmic angiography. Designed to be administered intravenously, indocyanine green solution (ICG) contains less than 5% sodium iodide. Upon intravenous injection, ICG rapidly binds to its principle carrier, plasma protein, and is thereby confined to the vascular space. This agent, with a half-life of 150 to 180 seconds, is removed exclusively by the liver from circulation to bile juice. Furthermore, due to poor uptake, ICG is not suitable for angiography or functional output analysis of kidney, lung, cerebro-spinal, or peripheral tissues.