AIM: To observe the changes of intraocular pressure and choroidal thickness after hemodialysis in patients with chronic renal failure, and to explore the impact of hemodialysis on blood supply.

METHODS: Totally 55 patients(110 eyes)with chronic renal failure who had been treated for a long time in our hospital were selected to test plasma osmotic pressure. Before and after hemodialysis 5min, hemodialysis venous blood was collected, and plasma osmotic pressure was measured. Before hemodialysis 1h and after hemodialysis 1h, intraocular pressure was measured; intraocular pressure and choroidal thickness were compared before and after hemodialysis measured by enhanced depth imaging technique of optical coherence tomography(OCT).

RESULTS: After hemodialysis plasma osmotic pressure reduced, and the difference was statistically significant(t=12.73, P<0.01); and intraocular pressure increased after hemodialysis and the difference was statistically significant(t=2.07, P<0.05). The choroid thickness was thinner after hemodialysis, and the differences before and after hemodialysis at every measurement points(under central fovea, nasal, temporal, superior and inferior 1 and 3mm from the central fovea)were statistically significant(P<0.05).

CONCLUSION: After hemodialysis ocular pressure increased and the choroid thickness became thinner in chronic renal failure patients, which might affect the ocular blood flow state. It is suggested that the osmotic pressure gradient should be adjusted in hemodialysis patients and eye test and treatment must be given in necessity.