Evaluation of Henle's Fiber Layer with directional OCT in mild to moderate glaucoma patients

Abstract Purpose: To investigate the Henles’s fiber layer (HFL) to detect the damage that may develop in photoreceptors and axons in patients with mild to moderate glaucoma. Study Design: Single center retrospective study Methods: For this study, 25 eyes of 25 subjects diagnosed with glaucoma and 50 eyes of 50 age and sex matched healthy people were enrolled. Macular retinal thickness, peripapillary retinal nerve fiber layer (RNFL) thickness and macular ganglion cell-inner plexiform layer (GC-IPL) thickness measured on OCT. The OCT images with nasal, central and temporal tilt were processed with ImageJ software and HFL area was measured. Measurements were compared between the two groups. Results: The two groups were similar in age and gender. When the two groups were compared, HFL measurements were thinner in glaucoma patients (p<0.001). The inner inferior, outer temporal and outer superior quadrants of the retinal thickness were significantly thinner in the glaucoma group (p=0.012, p=0.010, p=0.004, respectively). All quadrants of GC-IPL thicknesses were significantly thinner in the glaucoma group. Additionally, statistically significant changes were detected differences in the thickness of the superior, inferior quadrants and average RNFL (p=0.029, p<0.001, p=0.001, respectively). Conclusion: From the early stages of glaucoma, automated HFL measurements can be used to monitor progression.