Differences In Optic Nerve Head Parameters Research Articles

Evaluation of Optic Nerve Head Parameters, Retinal Nerve Fiber Layer Thickness, and Ocular Perfusion Pressure in Migraine Patients.

BackgroundNeurovascular changes occur during the migraine is believed to cause alteration in cerebral and retinal circulation that possible result in damage to the brain and even retina or optic nerve. Retinal nerve fiber layer (RNFL) thickness measurement can be used as an index to assess ganglion cell and retinal nerve fiber damages. The aim of this study was to evaluate the optic nerve head (ONH) parameters, RNFL thickness, and ocular perfusion pressure (OPP) in migraine patients.MethodsThis was a cross-sectional study, conducted in Hospital Universiti Sains Malaysia, Kelantan from July 2016 to November 2018, involving patients with a confirmed diagnosis of migraine and controls. Ninety-four eyes of 47 migraine patients and 94 eyes of 47 healthy subjects were included in this study. Blood pressure and intraocular pressure were measured and OPP was calculated. ONH parameters and RNFL thickness were measured using optical coherence tomography (OCT) after pupillary dilatation. Statistical analysis was done using Statistical Package for the Social Science (SPSS Inc Version 24).ResultsWith respect to all means values of ONH parameters, there was no statistically significant difference between migraine patients and controls. For RNFL, there were significant reductions in average and superior RNFL thickness on both eyes with adjustment of age and gender (P-value: right eye (RE) average = 0.027; RE superior = 0.034; left eye (LE) average = 0.037; LE superior = 0.031). In view of OPP, there was no significant difference between migraine patients and controls (P-value = 0.172). Weak correlations were found between the ONH parameters and RNFL thickness with OPP, respectively, in migraine patients.ConclusionThis study showed no difference in ONH parameters between migraine patients and healthy subjects. There was significant thinning in average and superior RNFL for migraine patients. No difference found in OPP between both groups. ONH parameters and RNFL thickness had a weak correlation with OPP in migraine patients.

Ganglion Cell–Inner Plexiform Layer and Peripapillary Retinal Nerve Fiber Layer Thicknesses in Age-Related Macular Degeneration

To investigate changes of inner retinal layers and optic nerve head (ONH) in patients with dry age-related macular degeneration (AMD) and demonstrate the pattern of these changes. A total of 76 eyes classified as having dry AMD and 76 control eyes were included. Ophthalmologic evaluations included best-corrected visual acuity (BCVA) assessment, spectral-domain optical coherence tomography (SD-OCT), and Humphrey visual field (VF) test. The drusen area and volume were determined using the automated algorithm of the SD-OCT software. Macular ganglion cell-inner plexiform layer (mGCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses and ONH parameters, as well as VF parameters, were compared between groups. Macular GCIPL thickness was significantly lower in eyes with AMD than in controls (73.83 ± 7.13 vs. 82.00 ± 4.85 μm; P < 0.001), and mGCIPL thinning was observed in a ring-shaped pattern around the fovea. The pRNFL thickness was also significantly lower in eyes with AMD than in controls (88.69 ± 6.93 vs. 93.96 ± 8.33 μm; P < 0.001), but no significant difference in ONH parameters was found. An inverse correlation between drusen area and average mGCIPL thickness was found (r = -0.3253; P = 0.0064). Best-corrected visual acuity and VF parameters were worse in AMD eyes than in controls. The pattern of VF defects was mostly consistent with foveal or parafoveal scotoma. In eyes with dry AMD, mGCIPL and pRNFL thicknesses were lower than measurements in control eyes, and the average mGCIPL thickness was negatively correlated with the drusen area. However, the pattern of these changes differed from glaucomatous abnormalities.

Scanning laser ophthalmoscopic parameters of eyes with exfoliation syndrome

To evaluate optic nerve head (ONH) characteristics in patients with exfoliation syndrome (EXS). This was a cross-sectional, observational study in which 73 eyes from 73 patients with EXS and 93 eyes from 93 age-matched healthy subjects who met the inclusion criteria were included. Topographic measurements of the ONH and peripapillary retinal nerve fiber layer (RNFL) thickness were performed by confocal scanning laser ophthalmoscopy, using a Heidelberg retina tomograph. Outcomes of interest were studied by Student t test and chi-squared test. EXS patients and age-matched controls did not differ in ONH parameters. Nevertheless, the mean cup depth and height variation contour values were higher in the normal subjects (P = 0.07, P = 0.056, respectively). Mean RNFL thickness was 0.22 +/- 0.06 mm in the EXS group and 0.26 +/- 0.06 mm in the control group, (P = 0.001). Likewise, the RNFL cross-sectional area was significantly lower in exfoliative eyes (1.16 +/- 0.35 mm(2)) than in those of the control group (1.31 +/- 0.33 mm(2)) (P = 0.006). No significant differences in ONH parameters between EXS patients and age-matched healthy subjects were observed; however, RNFL measurements in eyes with EXS showed lower values.