Anatomical and Functional Evaluation of RNFL Parameters and Choroidal Thickness Changes in Patients with Chronic Renal Failure Undergoing Hemodialysis Using Spectral-Domain Optical Coherence Tomography and Visual Field

Background There is a structural analogy between the glomerular vascular network and the choroidal circulation. With hemodialysis (HD), lots of alterations occur in patients' homeostasis and metabolic parameters. These alterations affect the eye and may cause neuro-ophthalmologic complications. Aim To evaluate anatomical and functional changes of retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL), and changes in subfoveal choroidal thickness (SFCT) in patients with chronic renal failure (CRF) on HD. Methods This case control study was carried on 20 eyes of 20 CRF patients (HD group) and 20 eyes of 20 healthy individuals. 10 of the HD group were non-diabetic (NDM subgroup) and 10 were diabetic (DM subgroup). For all eyes, the thickness of peripapillary RNFL, GCL, and SFCT were measured by optical coherence tomography (OCT) (RS-3000; NIDEK, Japan) and visual field (VF) analysis using Humphrey field analyzer (Carl Zeiss, USA). Results A statistically significant decrease in peripapillary RNFL thickness in HD group when compared to the control group in most analyses, but did not amount to statistical significance in the temporal quadrant and in 5 of the studied clock hour sectors. There was also a statistically significant decrease in the macular GCL thickness of HD group when compared to the control group in both hemifields, and in all of the 8 subfields. The results of the SFCT reported in HD group were also significantly less than that reported in the control group. Analysis of results from VF demonstrated a highly significant depression in both MD and PSD of the HD group when compared to the control group. The difference between the NDM and DM subgroups was not significant in any of the studied parameters. Conclusion Our results demonstrate highly significant retinal and choroidal changes in CRF patients on HD. Thus, we recommend that CRF patients undergo regular ocular examination by OCT to prevent early ocular damage.