2020–2021 BCSC Basic and Clinical Science Course™
12 Retina and Vitreous
Part II: Disorders of the Retina and Vitreous
Chapter 09: Choroidal Disease
Choroidal Perfusion Abnormalities
The choroid has arterial supply from approximately 20 short posterior ciliary arteries and 2 anterior ciliary arteries. A network of branching arterioles distributes the blood throughout the choroid in a segmental fashion (Fig 9-7), ultimately leading to the choriocapillaris, and helps reduce the blood pressure as well. Although the vessels in the choriocapillaris exhibit relatively uniform patterns in any given region of the eye, the pressure gradients imposed by the feeding arterioles and draining venules establish a lobular perfusion pattern. Abnormalities in choroidal blood flow can be divided into several main categories based on the underlying disease process.
Arteritic Disease
In arteritic diseases such as giant cell arteritis (Fig 9-8) or granulomatosis with polyangiitis (formerly, Wegener granulomatosis) (Fig 9-9), inflammatory occlusion can cause sectoral areas of nonperfusion. Fluorescein or ICG angiography is typically performed in cases in which an arteritic cause of vision loss is suspected, because flow defects in the choroid are often undetected by ophthalmoscopy alone.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.