Disc Edema and Normal Visual Acuity

To the Editor.  —The report by Pavan et al in the December Archives (1980;98:2193-2195) on optic disc edema in juvenile-onset diabetes mentions that "the differential diagnosis of edematous optic discs with good vision and full fields includes papilledema and hypertension."For the sake of completeness, perhaps it should be mentioned that disc edema with preserved visual function can also be seen in cases of syphilitic optic perineuritis.¹ Although this diagnosis is made infrequently, cases still occur.² Additionally, mild cases of the so-called papillophlebitis, also known as optic disc vasculitis,³ can be bilateral and simulate papilledema. The differentiation of these clinical entities can be achieved, of course, by appropriate laboratory investigation.