Indocyanine green

Indocyanine Green (ICG) is a cyanine dye used in medical diagnostics. It is used in certain types of eye examination, including angiography, and to measure cardiac output, hepatic function, and liver blood flow, and for lymphography in vascular surgery.

History

Indocyanine Green was first synthesized in the 1950s and has been used in medical diagnostics since the 1960s. It was initially used in the study of cardiac function, but its use has expanded to include a wide range of medical applications.

Properties

Indocyanine Green is a tricarbocyanine dye that is water soluble and binds tightly to plasma proteins in the blood. It has a peak spectral absorption at about 800 nm. These properties make it ideal for use in certain diagnostic tests.

Medical uses

Indocyanine Green is used in a variety of medical applications. These include:

• Ophthalmology: ICG is used in angiography to examine the choroid, a layer of blood vessels in the eye. This can help diagnose conditions such as age-related macular degeneration and polypoidal choroidal vasculopathy.

• Cardiology: ICG can be used to measure cardiac output, the volume of blood being pumped by the heart. This can be useful in diagnosing and monitoring conditions such as heart failure.

• Hepatology: ICG is used to assess liver function and liver blood flow. This can help diagnose and monitor conditions such as cirrhosis and hepatitis.

• Vascular surgery: ICG is used in lymphography to visualize lymph vessels and nodes. This can be useful in procedures such as sentinel node biopsy.

Safety

Indocyanine Green is generally considered safe for use in medical diagnostics. However, like all medical procedures, its use carries some risk of side effects. These can include nausea, headache, and in rare cases, severe allergic reactions.

See also

• Fluorescein angiography
• Dye tracing
• Medical imaging