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Related to soft drusen: Retinal drusen
soft dru·sen(sawft drū'sĕn)
Type of exudative structure that appears ophthalmoscopically as placoid yellow lesions characterized histopathologically by localized serous detachments of the retinal pigment epithelium from the Bruch membrane.
A liquid or semisolid which has been discharged through the tissues to the surface or into a cavity. Exudates in the retina are opacities that result from the escape of plasma and white blood cells from defective blood vessels. They usually look greyish-white or yellowish and are circular or ovoid in shape. They are sometimes classified into three groups according to size: (1) punctate hard exudates, which often tend to coalesce. They are found in diabetic retinopathy, Coats' disease, etc.; (2) exudates of moderate size, such as 'cotton-wool or soft exudates' as, for example, in branch/central retinal vein occlusion, hypertensive retinopathy, etc. These 'exudates' have ill-defined margins and are actually areas of ischaemia containing cytoid bodies, unlike hard exudates which are generally lipid deposits; (3) larger exudates, as found in the severe forms of retinopathy.