Several techniques are commonly used to image blood vessels; obtaining these images is important because of the frequency with which ischemic processes affect the central nervous system.
The gold standard for intracerebral vascular imaging remains catheter angiography (Fig 2-11). With this technique, a catheter is placed intra-arterially and iodinated radiodense contrast dye is injected. Digital subtraction angiography (DSA) is a technique that reduces artifacts by subtracting densities created by the overlying bony skull. The contrast dye outlines the column of flowing blood within the injected vessel and demonstrates stenosis, aneurysms, vascular malformations, flow dynamics, and vessel wall irregularities such as dissections or vasculitis. The procedure has an overall morbidity of approximately 2.5%, primarily related to ischemia from emboli or vasospasm, dye-related reactions, or complications at the arterial puncture site (eg, hematoma). The use of digital subtraction technology has enhanced the ability to visualize vascular structures with smaller amounts of contrast dye.
Excerpted from BCSC 2020-2021 series: Section 5 - Neuro-Ophthalmology. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.