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What is Gunn sign is? and explain in detail?
Tapering of veins on either side of the crossings Gunn sign is seen in grade III hypeensive retinopathy. Grade 1 Generalized aeriolar attenuation Broadening of aeriolar light reflex Concealment of vein at A-V Crossings Grade 2 Severe generalized and focal aeriolar constriction A-V crossing change (Salus sign) Grade 3 Copper wiring of aerioles Venous banking distal to a-v crossing (bonnet's sign) Venous tapering on either side of the crossing (Gunn's sign) Right angle deflection of veins Flame shaped haemorrhages, cotton wool spots, hard exudates Grade 4 All changes of grade 3 Silver wiring of aerioles Disc oedema