INS and type 2 diabetes mellitus: A growing body of evidence suggests that both type 1 diabetes (T1DM) and type 2 diabetes (T2DM) patients exhibit a variety of neuropathological and neurobehavioural changes, including cerebrovascular changes,4 insulin signalling systems impairments in cerebral,5 poor visual space construction, planning and visual memory injury.6, 7 Diabetic encephalopathy (DE) is a series of neuropathological changes caused by diabetes, which common symptoms are paraesthesia, numbness and impaired cognition.8 The pathogenesis of DE is not completely clear.