[Electrical changes in the middle retinal layer in diabetic retinopathy].

An electroretinographic study was undertaken on 27 diabetic patients in order to catch the electric changes arose in the mid retinal layer under ischaemic conditions. Significant diminution of the amplitude of the b wave and less significant variation of its implicit time were observed during the progression of the diabetic retinopathy. An unexplained phenomenon--the amplification of the b wave--took place in certain cases of background retinopathy and was emphasised after adaptation of retina to darkness.