In order to better define ocular dynamics during hemodialysis, we studied intraocular pressure (IOP) and anterior chamber depth (ACD) serially during both acetate and bicarbonate hemodialysis in 10 stable hemodialysis patients. IOP did not change significantly in any patient during dialysis. In contrast, however, ACD decreased significantly during acetate but not bicarbonate dialysis. ACD could be maintained during acetate dialysis by concomitant administration of mannitol. We conclude that acetate dialysis might adversely affect ocular dynamics in susceptible patients with glaucoma or recent ocular surgery. In such individuals administration of mannitol or use of a bicarbonate dialysate should be considered.