Evaluation of choroidal and retinal thickness measurements using optical coherence tomography in non-diabetic haemodialysis patients.

The aim of this study is to evaluate the effects of haemodialysis with a high ultrafiltration rate on the choroidal and retinal thickness of non-diabetic end-stage chronic renal failure (CRF) patients using optical coherence tomography (OCT). Twenty-one eyes of 21 male CRF patients aged between 46 and 80 years were included in this prospective study. Retinal and choroidal thicknesses of the patients were measured using high-resolution OCT line scans with the activated enhanced depth imaging mode before and shortly after haemodialysis. Retinal and choroidal thickness measurements were taken at the fovea and at two points that were 1,500 μm nasal and temporal to the fovea. The relationships between the haemodynamic changes, intraocular pressure (IOP) and central corneal thickness (CCT) were also evaluated. The mean choroidal thicknesses before haemodialysis at the subfoveal, temporal and nasal locations were 232.81 ± 71.92, 212.43 ± 70.50 and 182.14 ± 68.88 μm, respectively. The mean choroidal thicknesses after haemodialysis at the subfoveal, temporal and nasal locations were 210.90 ± 65.53, 195.38 ± 66.48 and 165.19 ± 66.73 μm, respectively. There were significant differences between the choroidal thicknesses before and after haemodialysis (p < 0.001 for all). The mean retinal thicknesses before haemodialysis at the foveal, temporal and nasal locations were 215.86 ± 41.06, 308.86 ± 37.73 and 338.00 ± 33.32 μm, respectively. The mean retinal thicknesses after haemodialysis at the foveal, temporal and nasal locations were 216.90 ± 39.70, 313.86 ± 32.89 and 335.29 ± 36.85 μm, respectively. There was no significant difference between the retinal thicknesses before and after haemodialysis (p > 0.05 for all). The mean CCT decreased insignificantly from 550.48 ± 17.46 to 548.10 ± 21.12 μm (p = 0.411). The mean IOP decreased significantly from 14.09 ± 2.58 to 12.54 ± 2.23 mmHg (p = 0.003), which did not correlate with the CCT [r = (-)0.134, p = 0.562]. Haemodialysis with a high ultrafiltration volume did not alter the retinal thickness but caused a significant choroidal thinning and an IOP decrease in non-diabetic end-stage CRF patients.