Investigations are used only for the wet form of macular degeneration or if there has been a sudden change in the central area of vision.

Optical Coherence Tomography (OCT) is the usual first investigation to diagnose problems affecting the macula. A special camera produces a detailed cross-sectional image to show the various layers of the retina. It is quick to perform, requires no injection and it often avoids the need for an angiogram.

Fluorescein Angiography is an investigation to examine the blood vessels in the retina. A small amount of orange fluorescein dye is injected into a blood vessel of the forearm. It travels in the bloodstream and reaches the eye 10 seconds later, when a sequence of flash photographs is taken over the next five minutes. The pictures identify areas of the retina where blood vessels may be leaking or blocked and help in deciding if treatment will help.