The effect of hemodialysis on individual retinal layer thickness.

PURPOSE The aim of this study was to employ newly developed advanced image analysis software to evaluate changes in retinal layer thickness following hemodialysis. METHODS A non-randomized prospective study of patients with end-stage renal disease assessed on the same day before and after hemodialysis. Intraocular pressure and central corneal thickness were analyzed, and spectral domain optical coherence tomography results were automatically segmented using the Orion software and then compared. All patients had normal retinal optical coherence tomography findings before hemodialysis. RESULTS Of the 31 suitable end-stage renal disease patients treated with hemodialysis who provided consent to participate, seven were unable to complete all evaluations, leaving 24 patients for analysis in the final study group. Their mean age was 66.67±14.3 years (range: 35-88), and 62.5% were males. Mean central corneal thickness did not change following hemodialysis (563.4±30.2 µm to 553.1±47.2 µm, p=.247), while mean intraocular pressure decreased (14.48±2.5 mmHg to 13.16±2.28 mmHg, p=.028). Individual mean retinal layer thickness showed no significant change, including the retinal nerve fiber layer (40.9±6.8 µm to 40.1±5.2 µm, p=.412), the ganglion cell and the inner plexiform layer (68.66±8 µm to 69.03±7.6 µm, p=.639), and the photoreceptor layer (50.26±2.8 µm to 50.32±3.1 µm, p=.869). Total retinal thickness similarly remained constant, with a mean of 303.7±17.3 µm before and 304.33±18.4 µm after hemodialysis (p=.571). CONCLUSIONS Thickness of retinal layers, as assessed by individual segmentation, and central corneal thickness were not affected by hemodialysis treatment, while intraocular pressure was significantly reduced among patients with end-stage renal disease without pre-existing ocular pathology who were undergoing hemodialysis. These results support the view that hemodialysis does not have a negative impact on the retinal morphology of end-stage renal disease patients, who comprise a population with high rates of diabetic and/or hypertensive retinopathy as well as vision-threatening complications.