AIM: To investigate the correlation between intraocular pressure(IOP)changes pre- and post-hemodialysis(HD)and the biometric structure of the anterior chamber in patients of chronic renal failure.

METHODS: Fifty-two patients(take right eye as study one)with hemodialysis that were diagnosed with chronic renal failure by nephrology in our hospital from January 2015 to December 2015 were collected. Fifty-two eyes were divided into four groups based on Shaffer classification combined with ultrasound biomicroscopy(UBM)and gonioscopy manifestations: wide angle group, narrow angle group, extremely narrow group and close angle group. Venous blood was collected to get plasma colloid osmotic pressure before HD and within 60s after HD. IOP was measured with rebound intraocular pressure gauge in a supine positon approximately 30min before starting HD, 2h after HD begin and approximately 30min after HD ending. Approximately 30min before and after HD, central corneal thickness was measured with corneal endothelial cell counter, central anterior chamber depth and lens thickness were taken by A scan, angle opening distance, trabecular iris angle, iris thickness and ciliary body thickness were measured by UBM.

RESULTS: Plasma osmotic pressure reduced after HD, the difference was statistically significant(t=3.04, P<0.05). The means of IOPs among three measurement points were not all the same(F=41.69, P<0.01). The IOP in 2h after HD had significant difference compared with before HD(P<0.01).The IOP in 30min after HD ending had significant difference compared with 2h after HD(P<0.01). The means of IOPs among three groups were not all the same(F=6.44, P<0.01). The IOP in extremely narrow angle group had significant difference compared with that in wide angle group and narrow angle group(P<0.05). Ciliary body thickness decreased after HD in every group, while only in wide angle group showed significant change after ending HD(t=2.61, P<0.05). Central corneal thickness, central anterior chamber depth, angle opening distance, trabecular iris angle and iris thickness decreased, while lens thickness increased after HD. But all these changes between before HD and after HD in every group had no significant difference.

CONCLUSION: The influence of hemodialysis on IOP is related to the biometric structure of the anterior chamber. And extremely narrow angle is risk factor of elevated IOP during hemodialysis, narrow angle may be a risk factor. While patients with wide angle is relatively safe. We suggest to take ocular examination as early as possible for patients with hemodialysis, and focus on patients with narrow angle.