Abstract
BackgroundThis study aimes to characterize the fundus structural changes in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and the correlation between macular vessel density, retinal nerve fibre layer (RNFL) parameters and visual field sensitivity (VFS) in NAION patients.MethodsA retrospective case control study was performed using 37 eyes with NAION, 30 uninvolved contralateral eyes, and 27 eyes of healthy age-matched subjects. Data on the retinas and choroidal vessel densities and VFS were compared among the three groups.ResultsThe NAION group exhibited significantly lower RNFL thicknesses, lower ganglion cell complexes (GCC), larger global loss volume (GLV) values and focal loss volume (FLV) values when compared with both uninvolved eyes and healthy eyes (p < 0.01 for all comparisons). The superficial vessel density (SVD) valus (whole, parafovea, superior-hemi and inferior-hemi) were significantly lower in NAION eyes, followed by uninvolved eyes and healthy eyes (p < 0.01; LSD, p < 0.05 for all comparisons). The deep vessel density (DVD) values (parafovea, superior-hemi and inferior-hemi) were the lowest by a significant value in NAION eyes, followed by uninvolved eyes and healthy eyes (p < 0.01; LSD, p < 0.05 for all comparisons). However, DVD value measurements (whole and fovea) of healthy and uninvolved eyes were not significantly different. The average threshold deviation (TD) was − 11.02 ± 3.75 dB for the overall field region, − 6.01 ± 2.21 dB for the affected superior field region and − 9.98 ± 3.34 dB for the affected inferior field region in NAION eyes. A statistically significant correlation was found between the RNFL thickness and visual field(VF) loss (r = − 0.788, p < 0.001).ConclusionIn addition to peripapillary vascular changes occurring in NAION eyes, macular vessel density is also involved. Furthermore, NAION-uninvolved eyes exhibited abnormalities compared with healthy eyes. This indicates that vascular changes may occur before changes in retinal thickness at the early stages of NAION.
Highlights
This study aimes to characterize the fundus structural changes in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and the correlation between macular vessel density, retinal nerve fibre layer (RNFL) parameters and visual field sensitivity (VFS) in NAION patients
The underlying pathophysiology of NAION is unknown; it is presumed to be vascular in aetiology and caused by infarction of the retrolaminar portion of the optic nerve head (ONH), which is supplied by the short posterior ciliary arteries [4], mechanical aetiologies have been postulated [5]
The pairwise comparisons of RNFL showed that NAION eyes (70.86 ± 10.50 μm) had significantly lower RNFL thickness values compared with both uninvolved eyes (98.90 ± 10.55 μm) and healthy eyes (102.11 ± 7.21 μm) [least significant difference (LSD), p < 0.001 for both]
Summary
This study aimes to characterize the fundus structural changes in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and the correlation between macular vessel density, retinal nerve fibre layer (RNFL) parameters and visual field sensitivity (VFS) in NAION patients. The insufficient blood supply of short posterior ciliary arteries (PCA) may lead to anterior optic nerve hypoperfusion, which may cause the occurrence of NAION [3]. The underlying pathophysiology of NAION is unknown; it is presumed to be vascular in aetiology and caused by infarction of the retrolaminar portion of the optic nerve head (ONH), which is supplied by the short posterior ciliary arteries [4], mechanical aetiologies have been postulated [5]. Macula is less than 2% of the retina, it contains 30% of retinal ganglion cells (RGC)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
