Exudates

Retinal Exudates

Retinal exudates are lipid residues that leak from damaged capillaries.  They can be associated with retinal vascular conditions and commonly seen in diabetic retinopathy, retinal vein occlusions and choroidal neovascular membranes.  In diabetic retinopathy, hard exudates with associated retinal thickening located within 500 microns of the center of the fovea is referred to as clinically significant macular edema (CSME).  The ETDRS report 22 found an association of hard exudates with elevated serum lipid levels.  Hard exudates refer to retinal exudates secondary to leakage, this is not to be confused with soft exudates described by the ETDRS commonly called cotton wool spots.

 

Figure 1: Retinal hard exudates located mainly in the outer plexiform and some in the outer nuclear layer appear as hyperreflective on SD-OCT.

 

Peripapillary retinal exudates

Peripapillary retinal exudates can be associated with optic disc edema, peripapillary central serous chorioretinopathy or peripapillary choroidal neovascular membranes.  

 

Figure 2: Peripapillary retinal exudates with associated subretinal fluid in a patient with optic disc edema.