Comparison of the pattern of peripapillary retinal nerve fiber layer damage between open-angle glaucoma and anterior ischemic optic neuropathy

Purpose: The aim of this study was to evaluate thiol/disulfide homeostasis and ischemia-modified albumin levels with primary open-angle glaucoma, ocular hypertension, and control group; also to interpret the correlation between these biochemical parameters and retinal nerve fiber layer analysis. Material and methods: In a prospective cross-sectional study, 30 primary open-angle glaucoma cases, 30 ocular hypertension cases, and 30 control subjects were included in the study. Native thiol, total thiol, and disulfide measurements and disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol ratios were evaluated as thiol–disulfide homeostasis. Albumin and ischemia-modified albumin parameters were also evaluated. All cases underwent detailed ophthalmologic examination including visual acuity, retinal nerve fiber layer via optical coherence tomography, intraocular pressure, and central corneal thickness measurements and visual field analysis by 24-2 Swedish Interactive Threshold Algorithm (SITA) Standard visual field test. Results: Primary open-angle glaucoma group had significantly higher ischemia-modified albumin values than ocular hypertension and control group (p < 0.001). Native thiol and total thiol values of control group were statistically higher than those of primary open-angle glaucoma and ocular hypertension groups. The correlation between the temporal retinal nerve fiber layer value and ischemia-modified albumin, disulfide/native thiol, and disulfide/total thiol values of the primary open-angle glaucoma patients included in the study was moderate correlation in negative direction (r = –0.46, r = –0.39, r = –0.39, respectively), whereas there was a statistically significant moderate correlation in positive direction between the native thiol/total thiol values (r = 0.39) (p < 0.05). Conclusion: These findings have reinforced the role of oxidative stress in the etiopathogenesis of primary open-angle glaucoma, suggesting that the thinning retinal nerve fiber layer may be associated with oxidative stress in favor of prooxidant shift.

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Pattern electroretinogram changes in patients with primary open-angle glaucoma in correlation with visual field and optical coherence tomography changes

European Journal of Ophthalmology ◽

10.1177/1120672119872606 ◽

2019 ◽

Vol 30 (6) ◽

pp. 1362-1369 ◽

Cited By ~ 2

Author(s):

Asmaa M Elgohary ◽

Hazem A Elbedewy ◽

Hisham A Saad ◽

Tarek M Eid

Keyword(s):

Nerve Fiber ◽

Retinal Nerve Fiber Layer ◽

Primary Open Angle Glaucoma ◽

Open Angle Glaucoma ◽

Pattern Electroretinogram ◽

Average Thickness ◽

Open Angle ◽

Fiber Layer ◽

Nerve Fiber Layer ◽

Retinal Nerve Fiber

Purpose: To study the pattern electroretinogram changes in primary open-angle glaucoma patients in correlation with visual field changes and optical coherence tomography measurements of retinal nerve fiber layer thickness in the peripapillary region in an attempt to evaluate the clinical value of pattern electroretinogram as an objective test of functional deficit in glaucoma. Patients and Methods: The study included 81 eyes of 81 participants: 50 primary open-angle glaucoma patients, 16 primary open-angle glaucoma suspects, and 15 controls. All subjects underwent visual field testing using 24-2 Humphrey standard automated perimetry, peripapillary retinal nerve fiber layer average thickness using the 3.4-mm circular scan of the Heidelberg OCT spectralis and pattern electroretinogram using CSO RetiMax device in accordance with the International Society for Clinical Electrophysiology of Vision guidelines. Results: We had three main groups: normal, glaucoma suspect, and primary open-angle glaucoma patients, and the last group included three subgroups: mild, moderate, and severe. There was significant difference in the visual field mean deviation, peripapillary retinal nerve fiber layer average thickness, and most pattern electroretinogram measured parameters between the three main groups and in between primary open-angle glaucoma subgroups. There was significant positive correlation between visual field mean deviation and the peripapillary retinal nerve fiber layer average thickness, P50 amplitude, and P50–N95 amplitude (p < 0.001, p = 0.018, and p < 0.001, respectively). Significant negative correlation was also found between peripapillary retinal nerve fiber layer average thickness and N95 amplitude (p < 0.001). Significant positive correlation was found between retinal nerve fiber layer average thickness and P50–N95 amplitude (p = 0.001). Significant negative correlation was found between peripapillary retinal nerve fiber layer average thickness and N95 amplitude (p = 0.001) and significant positive correlation of retinal nerve fiber layer average thickness with P50–N95 amplitude (p = 0.017) in primary open-angle glaucoma patients. Conclusion: Peripapillary retinal nerve fiber layer average thickness shows significant negative correlation with pattern electroretinogram N95 amplitude and a significant positive correlation with P50–N95 amplitude. In combination with optical coherence tomography, pattern electroretinogram can be used to objectively assess functional loss in glaucoma.

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