Digital Angiography with Indocyanine
Angiography with indocyanine is supplementary to fluoroangiography. The two techniques are similar but the duration of the former is greater (at least 30 minutes). Mydriasis of the pupil is required; a venous catheter needs to be inserted in the patient’s hand and dye needs to be infused (Indocyanine). Then fundus images are taken using a camera with special filters.
The indocyanine molecule has different characteristics than the fluorescein molecule. Thus, indocyanine angiography can produce more detailed images of the deeper layers of the fundus, such as the choroid. Furthermore, an imaging of the layers of the retina and the choroid is performed even in the presence of extended hemorrhages, where fluorescein angiography is often inefficient.
The most common indicator for the use of fluorescein angiography is the presence of large pigment epithelium detachments and of extended epiretinal and subretinal hemorrhages.
Furthermore, there is a variety of conditions which require the use of fluorescein angiography for the physician to make or eliminate a diagnosis, such as central serous chorioretinopathy, polypoid choroidal vasculopathy, hemangiomas, choroidal melanomas as well as inflammatory diseases of the choroid.