We have registered the ERG in 26 chronic uraemics treated with periodic haemodialysis, nearly always finding a subnormal b-wave. In 11 chronic uraemics treated only with dietetic-conservative therapy, the electroretino- gram resulted only slightly reduced and with a voltage clearly superior to that of the previous group. REFERENCES Agzamova, H.S. Tonographic values in patients with chronic renal insufficiency. Of tal. Zh. 20: 32-34 (1975). Berlyne, G.M. Microcrystalline conjunctival calcification in renal failure. Lancet II: 366-370 (1968). Biagini, M. & E.M. Gloria. Comportamento della...