[The pathogenesis of cotton-wool spots].

Cotton-wool spots have been recognized as distinct ophthalmoscopic entities, yet the pathogenesis of these lesions has not been fully appreciated until now. Cotton-wool spots should be regarded as localised accumulations of axoplasmic debris in the retinal nerve-fibre lay, which result from interruption of axoplasmic transport. Cotton-wool spots could be found especially in diabetic retinopathy, retinopathy from nephropathy, collagen diseases, retinal vein occlusions and cachexia. Any factor responsible for local interruption of axonal flow in the retinal nerve-fibre layer will give rise to similar accumulations, although, pathogenically speaking, the cause is usually ischaemia.