Association of SIX1-SIX6 polymorphisms with peripapillary retinal nerve fibre layer thickness in children

PurposeAssociation of SIX1-SIX6 variants with peripapillary retinal nerve fibre layer (p-RNFL) thickness had been reported in adults. This study aimed to investigate these associations in children, with further explorations by spatial, age and sex stratifications.Methods2878 school children aged between 6 and 9 years were enrolled from the Hong Kong Children Eye Study. Three single-nucleotide polymorphisms (SNPs) at the SIX1-SIX6 locus were genotyped. The association of each SNP with p-RNFL thickness (including global and sectoral thickness) were evaluated using multiple linear regression.ResultsSNPs rs33912345 (p=7.7×10−4) and rs10483727 (p=0.0013) showed significant associations with temporal-inferior p-RNFL thickness. The C allele of rs33912345 was associated with a thinner temporal-inferior p-RNFL by an average of 2.44 µm, while rs10483727-T was associated with a thinner temporal-inferior p-RNFL by 2.32 µm. The association with temporal-inferior p-RNFL was the strongest in the 8–9 year-old group for rs33912345 (p=5.2×10−4) and rs10483727 (p=3.3×10−4). Both SNPs were significantly associated with temporal-inferior p-RNFL thickness in boys (p<0.0017), but not in girls (p>0.05). In contrast, rs12436579-C (β=1.66; p=0.0059), but not rs33912345-C (β=1.31; p=0.052) or rs10483727-T (β=1.19; p=0.078), was nominally associated with a thicker nasal-inferior p-RNFL.ConclusionsBoth rs33912345 and rs10483727 at SIX1-SIX6 were associated with p-RNFL thickness in children, especially at the temporal-inferior sector, with age-dependent and sex-specific effects. SNP rs12436579 was associated with nasal-inferior p-RNFL thickness. Our findings suggested a role of SIX1-SIX6 in RNFL variation during neural retina development in childhood.

Factors Associated with Changes in Peripapillary Retinal Nerve Fibre Layer Thickness in Healthy Myopic Eyes

Myopic people face an elevated risk of primary open angle glaucoma. Changes in the fundus in people with high myopia often lead to misdiagnosis of glaucoma, as this condition has many clinical signs in common with myopia, making the diagnosis of glaucoma more challenging. Compared to reduction of the visual field, a decrease in retinal nerve fibre layer (RNFL) thickness occurs earlier in glaucoma, which is widely considered useful for distinguishing between these conditions. With the development of optical coherence tomography (OCT), RNFL thickness can be measured with good reproducibility. According to previous studies, this variable is not only affected by axial length but also related to the patient’s age, gender, ethnicity, optic disc area, and retinal blood flow in myopia. Herein, we intend to summarize the factors relevant to the RNFL in myopia to reduce the false-positive rate of glaucoma diagnosis and facilitate early prevention of myopia.

Evaluation of retinal nerve fibre layer thickness as a possible measure of diabetic retinal neurodegeneration in the EPIC-Norfolk Eye Study

Background/aimsMarkers to clinically evaluate structural changes from diabetic retinal neurodegeneration (DRN) have not yet been established. To study the potential role of peripapillary retinal nerve fibre layer (pRNFL) thickness as a marker for DRN, we evaluated the relationship between diabetes, as well as glycaemic control irrespective of diabetes status and pRNFL thickness.MethodsLeveraging data from a population-based cohort, we used general linear mixed models (GLMMs) with a random intercept for patient and eye to assess the association between pRNFL thickness (measured using GDx) and demographic, systemic and ocular parameters after adjusting for typical scan score. GLMMs were also used to determine: (1) the relationship between: (A) glycated haemoglobin (HbA1c) irrespective of diabetes diagnosis and pRNFL thickness, (B) diabetes and pRNFL thickness and (2) which quadrants of pRNFL may be affected in participants with diabetes and in relation to HbA1c.Results7076 participants were included. After controlling for covariates, inferior pRNFL thickness was 0.94 µm lower (95% CI −1.28 µm to −0.60 µm), superior pRNFL thickness was 0.83 µm lower (95% CI −1.17 µm to −0.49 µm) and temporal pRNFL thickness was 1.33 µm higher (95% CI 0.99 µm to 1.67 µm) per unit increase in HbA1c. Nasal pRNFL thickness was not significantly associated with HbA1c (p=0.23). Similar trends were noted when diabetes was used as the predictor.ConclusionSuperior and inferior pRNFL was significantly thinner among those with higher HbA1c levels and/or diabetes, representing areas of the pRNFL that may be most affected by diabetes.

Retinal Nerve Fibre Layer Thickness Change Following Femtosecond Laser-Assisted in situ Keratomileusis

Purpose: To evaluate the effect of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) on retinal fovea thickness, volume, and retinal nerve fibre layer (RNFL) thickness.Methods: Thirty-seven eyes (37 patients) undergoing FS-LASIK were included in this prospective study. Optical coherence tomography (OCT) was performed 1 day before, 1 h and 1 day after FS-LASIK surgery.Result: Eighteen male and nineteen females were enrolled. Mean patient age was 22.94 ± 4.22 years. One hour postoperatively, macula fovea thicknesses, macula fovea volume, macula parafovea thickness, macula parafovea volume, macula perifovea thickness, macula perifove volume, temporal RNFL thickness, and superior RNFL thickness measures showed significant decrease (t = 6.171, 6.032, and 9.837, 9.700, 2.532, 4.393, 4.926, 2.265; p = 0.000, 0.000, 0.000, 0.000, 0.016, 0.000, 0.000, and 0.011). Day 1 post-operation, macula fovea thicknesses, macula fovea volume, macula parafovea thickness, macula parafovea volume, and inferior RNFL thickness measures showed significant change compared to preoperative measures (t = 3.620, 3.220, 2.901, 2.910, 3.632; p = 0.001, 0.003, 0.006, 0.006, and 0.001).Conclusion: Our data suggest there are alterations in retinal foveal and RNFL measurements by OCT 1 h and 1 day after FS-LASIK surgery.

Retinal Nerve Fibre Layer Assessment in Glaucoma and Glaucoma Suspect by Optical Coherence Tomography (OCT)

Background Glaucoma is a progressive optic neuropathy characterized by structural changes in the optic nerve head, retinal nerve fiber layer (RNFL) defect, and accompanying visual field damage (VFD). In glaucoma management, detecting progression is essential in both early and late stages of the disease. In patients with an established diagnosis of glaucoma, evidence of progression will influence a clinician’s decision whether to modify glaucoma therapy. In patients who are suspected of having the disease, progression detection can confirm the diagnosis, and help decide how to manage the patient. Although standard automated perimetry has been the most commonly used test to monitor glaucomatous progression, evidence suggests that in some eyes substantial structural damage can be detected before the development of clinically detectable VFD. Objective To compare retinal nerve fibre layer thickness between glaucoma and glaucoma suspects. Methods We conducted our cross sectional comparative study on Forty eight eyes from patients recruited from Ain Shams University Hospitals, Ophthalmology Department during the period from February 2019 to December 2019. The Forty eight eyes were recruited in this study and divided into 2 groups. Group A- (Twenty-four eyes with moderate open angle glaucoma) and Group B- (Twenty four eyes with criteria of glaucoma suspects). Results There was highly Significant difference as regards OCT parameters of the patients (p &lt; 0.001 for all). As the mean value of Cup/disc ratio was lower in Glaucoma Suspected cases, while Total RNFL, RNFL Superior and RNFL Inferior was higher in Glaucoma Suspected cases than patients with Moderate glaucoma. This study showed that; by using ROC-curve analysis, cup to disc ratio (CDR) at a cutoff point (&gt;0.59) detected patients with glaucoma, with excellent accuracy, sensitivity= 95% and specificity= 100%. Also, by using ROC-curve analysis, superior RNFL at a cutoff point (≤116) detected patients with glaucoma, with fair accuracy, sensitivity= 66% and specificity= 91%. While inferior RNFL at a cutoff point (≤113) detected patients with glaucoma, with good accuracy, sensitivity= 70% and specificity= 95%. Conclusion In conclusion, structural progression measured using SD OCT was associated with functional progression shown in VF loss in glaucoma suspect or preperimetric glaucoma eyes and in glaucomatous eyes. Average, inferior and superior RNFL attenuations were the most important risk factors for visual field progression.

PERIPAPILLARY RETINAL NERVE FIBER LAYER THICKNESS IN MYOPIA USING OPTICAL COHERENCE TOMOGRAPHY

This is a observational cross sectional study conducted in tertiary care hospital in the department of ophthalmology to evaluate the effect of myopia on peripapillary retinal nerve fiber layer thickness in various quadrants and clock hour positions using optical coherence tomography ,with a sample size of 100 myopic eyes.Out of 100, 30 were males and there is significant decrease in peripapillary retinal nerve fibre layer thickness in high myopics when compared to low and moderate myopics and also decrease retinal fibre layer thickness in all quadrants except temporal quadrant.