Purpose: To evaluate the retinal nerve fiber layer (RNFL) thickness, ganglion cell-inner plexiform layer (GCL+) thickness, and macular choroidal thickness (mCT) in patients with chronic obstructive pulmonary disease (COPD) using spectral domain optical coherence tomography (SD-OCT).
Methods: A total of 79 COPD patients and 71 age- and sex-matched healthy individuals were enrolled in this prospective cross-sectional study. The patients were divided into two subgroups (with mild-to-moderate COPD and severe COPD) using spirometric data suggested by the Global Initiative for Chronic Obstructive Lung Disease guideline. The RNFL, GCL+, and mCT were compared between groups.
Results: The average and nasal RNFL thicknesses in the COPD group were significantly lower than those in control group (p = 0.023 and 0.027 respectively). Statistically significant reductions in average thickness and in those of all six wedge-shaped GCL+ sectors were evident in the COPD group compared with control group and were more marked in patients with severe COPD. The other RNFL data did not differ significantly between COPD and control groups. The mCT was somewhat thinner at all the measured locations in COPD group compared with control group, but statistically significance was not attained.
Conclusions: The study results revealed significant average, nasal RNFL, global GCL+ loss, and a nonsignificant choroidal thinning in patients with COPD compared to healthy subjects. The eye seems to be one of the affected tissues during the natural course of the COPD.
Keywords: Chronic obstructive pulmonary disease; choroid; hypoxia; macular ganglion cell layer/inner plexiform layer; optical coherence tomography; retinal nerve fiber layer thickness.