2020–2021 BCSC Basic and Clinical Science Course™
12 Retina and Vitreous
Part II: Disorders of the Retina and Vitreous
Chapter 09: Choroidal Disease
Central Serous Chorioretinopathy
The extent of the detachment can be documented with color fundus photographs. Autofluorescence imaging shows the accumulation of shed outer segments in the subretinal space, as well as distributed defects of the RPE. It has been theorized that the white dots seen under the retina are macrophages with fluorophores from phagocytized outer segments (Fig 9-2). Eyes with chronic CSC can display descending tracts during both fluorescein and autofluorescence imaging (Fig 9-3). Enhanced depth imaging optical coherence tomography (EDI-OCT) shows thickening of the choroid and, in areas where thickening is most prominent, posterior loculation of fluid in the deep choroid. Figure 9-4 shows the internal structure of a healthy choroid, while Figure 9-5 shows the choroid in 1 healthy eye and in 3 eyes with CSC. Although ICG angiography is able to visualize choroidal vascular hyperpermeability (Fig 9-6), it has largely been supplanted by OCT, even for detecting possible coexisting choroidal neovascularization (CNV), which may be present in up to 20% of cases in individuals over the age of 50 years. OCT angiography seems to be adept at detecting type 1 CNV in these patients.
Figure 9-2 CSC with white dots. A, A color fundus photograph shows an ovoid elevation of the retina that has white dots on the undersurface (arrowheads). B, Fluorescein angiography reveals a single leakage point. C, The elevated retina, seen in cross section, has a thick coat on its inner surface that has autofluorescent characteristics consistent with retinal outer segment–derived fluorophores. These fluorophores are therefore considered to be derived from the outer segments that could not be phagocytized by the retinal pigment epithelium (RPE) because of the physical separation, caused by the fluid, of the retina and RPE. The region of shaggy photoreceptors contains punctate dots that are highly reflective; it has been theorized that these dots are macrophages.
(Courtesy of Richard F. Spaide, MD.)
Figure 9-3 Autofluorescence abnormalities in CSC. A, Color photographs show the right and left eyes of a patient with CSC. Although subtle pigmentary changes are visible, it can be difficult to discern where fluid has accumulated. B, Autofluorescent images show widespread abnormalities induced by the presence of subretinal fluid, particularly the descending tracts caused by the fluid.
(Used with permission from Imamura Y, Fujiwara T, Spaide RF. Fundus autofluorescence and visual acuity in central serous chorioretinopathy. Ophthalmology. 2011;118:700–705.)
Imamura Y, Fujiwara T, Margolis R, Spaide RF. Enhanced depth imaging optical coherence tomography of the choroid in central serous chorioretinopathy. Retina. 2009;29(10):1469–1473.
Spaide RF, Klancnik JM Jr. Fundus autofluorescence and central serous chorioretinopathy. Ophthalmology. 2005;112(5):825–833.
Figure 9-4 The internal structure of the healthy choroid. The choroidal vessels decrease in diameter from the outer to the inner choroid. A, The larger vessels (white arrowheads) are dark in the center with a thick hyperreflective wall. The medium-sized vessels (yellow arrowheads) have a smaller hyporeflective area in the center and a hyperreflective wall. B, As vessel diameter decreases, the central hyporeflective area decreases until it is not visible. At that size, the vessel appears as a white hyperreflective structure (arrows). Note the delineation of the hyporeflective line near the junction with the inner sclera, which appears to be in the suprachoroidal space. The red arrow points to a vessel coursing through the sclera.
(Used with permission from Mrejen S, Spaide RF. Optical coherence tomography: imaging of the choroid and beyond. Surv Ophthalmol. 2013;58:387–429.)
Figure 9-5 The choroid is seen in cross section using enhanced depth imaging optical coherence tomography (EDI-OCT). Subfoveal choroidal thickness was measured vertically from the outer border of the RPE to the inner border of the sclera (brackets) in a healthy eye in a 55-year-old man (A) and in 3 representative eyes with CSC: in a 44-year-old man (B), a 57-year-old man (C), and a 63-year-old man (D).
(Used with permission from Imamura Y, Fujiwara T, Margolis R, Spaide RF. Enhanced depth imaging optical coherence tomography of the choroid in central serous chorioretinopathy. Retina. 2009; 29:1469–1473.)
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.