Primary Open Angle Glaucoma: The Pathophysiolgy, Mechanisms, Future Diagnostic and Therapeutic Directions

Umezurike, Benedict C.; Akhimien, Moses Obeimen; Udeala, Okechukwu; Green, Uzoamaka G.; Okpechi-Agbo, Ugonma; Ohaeri, Maureen U.

doi:10.9734/or/2019/v10i330106

Cited by 4 publications

(4 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Retinal nerve fibres transmit visual signals from the lightsensitive cells of the eye to the brain through the visual nerves [32]. The medically visible portion of the ON papilla is called an OD [33]. Glaucoma usually causes various forms of ON damage.…”

Section: Significance Of Optic Disc and Retina Vessel Detection For D...mentioning

confidence: 99%

Optic Disc and Vessel Segmentation in Retinal Images using Correlation Texture

Fatoki,

Owolawi,

Mapayi

2023

iCARTi

View full text Add to dashboard Cite

Globally, glaucoma has been recognized as the secondmost common reason for blindness. This affects the anatomy of the eyes, including blood vessels (BVs) and optic disc (OD). State-of-the-art literature has revealed that this disease is the root cause of degeneration in the OD, with some effects on the morphology of the BVs in the retina. These can result in total blindness if left untreated. Previous studies have shown that to effectively diagnose a disease, it is necessary to automatically detect the OD and the BVs with high accuracy in the fundus image. Segmentation of OD and BVs has, however, been challenging, due to the complex and poor segmentation performances. Such performances arise from the intricacies of vascular network width variation, illumination of images, and the structure of retinal images. Examples are retinal image boundaries on ODs and retinal lesions, due to disease. Hence the need for an investigation of the appropriate image feature(s) that will facilitate improvements to OD and BV segmentation performances. Texture is an important indicator used in image analysis for object segmentation. This work proposed the use of image-correlation texture information computational approaches for the segmentation of BVs, using variant window sizes; and OD using grayscale and green channel in the retinal images. This study revealed that the segmentation of BVs using variant window sizes (15x15) and (17x17) achieved high accuracy values of 95.11 per cent and 94.93 per cent; with accuracy values of 94.21 per cent and 93.98 per cent revealed in the DRIVE and STARE databases, respectively. Usually, sensitivity values of 74.84 per cent and 75.94 per cent, with average sensitivity values of 74.58 percent and 78.48 per cent, are achieved BV segmentation on the window sizes (15x15) and (17x17), indicated in DRIVE and STARE databases, respectively. Also, an average specificity value of 97.08 per cent and 96.77 per cent with average specificity values of 95.77 per cent and 95.18 per cent are achieved for BV segmentation on the window sizes (15x15) and (17x17), on DRIVE and STARE databases, respectively. Further, the segmentation of OD using grayscale achieved a slightly greater accuracy rate (98.59%) compared to the accuracy rate (98.36%) realized on green channel. This study also showed that the proposed approaches for BV and OD segmentation in this research achieved better results compared with several existing methods in the literature.

show abstract

Section: Significance Of Optic Disc and Retina Vessel Detection For D...mentioning

confidence: 99%

Optic Disc and Vessel Segmentation in Retinal Images using Correlation Texture

Fatoki,

Owolawi,

Mapayi

2023

iCARTi

View full text Add to dashboard Cite

show abstract

“…[6] POAG is mostly asymmetrical, with difference in cupping of more than 0.2, more severe in one eye than the other and with absence of underlying cause. [12] It is asymptomatic until visual impairment occurs. The irido-cornea (filtration) angle in POAG is usually open or wide, devoid of any narrowing tendency, with a normal anterior chamber depth.…”

Section: Introductionmentioning

confidence: 99%

Correlation of Intraocular Pressure and Random Blood Glucose Level in Patients with Primary Open-Angle Glaucoma

Azuamah

Chioma

Esenwah

2023

Int J Sci Healthcare Res

View full text Add to dashboard Cite

Primary open angle glaucoma (POAG) is a multifactorial chronic optic neuropathy, characterized by progressive loss of retinal ganglion cells (RGC), leading to structural damage to the optic nerve head (ONH), retinal nerve fiber layer (RNFL), with visual field defects. This study was carried out at the Department of Optometry Teaching Clinic, Federal University of Technology, Owerri, Imo State, Nigeria to determine the correlation between intraocular pressure and blood glucose levels in patients with primary open-angle glaucoma. A total of 37 subjects, 14 males and 23 females were used for the study. The Accu Chek glucometer was used to measure the random blood glucose level and the intraocular pressure was measured using the Perkins applanation tonometer. Results showed that the mean intraocular pressure was 16.57±3.97 while the mean random blood glucose level was 168.43±108.48. SPSS version 23 data analysis using the Pearson Product Moment Correlation Coefficient at 0.05 level of significance and 95% confidence interval revealed that there was no correlation between intraocular pressure level and random blood glucose level (P > 0.05). It was recommended that patients with primary open-angle glaucoma should frequently monitor their blood glucose levels. Keywords: Intraocular Pressure, Random Blood Glucose, Primary Open Angle Glaucoma, Diabetes Mellitus

show abstract

“…Glaucoma is a group of optic neuropathies with multifactorial etiology [ 1 ]. Being the second leading cause of blindness worldwide, it is a serious health condition with high socio-economic impact.…”

Section: Introductionmentioning

confidence: 99%

“…Its prevalence is expected to rise to 111 million by 2040 with primary open angle (POAG) and angle closure glaucoma (PACG) contributing to bulk of the cases [ 2 ]. Common risk factors for the disease include advanced age, elevated intraocular pressure (IOP), high refractive errors (± > 3.00D), decreased corneal thickness, race/ethnicity, and familial history [ 1 , 3 ]. The adverse visual outcome which is a major concern for glaucoma patients occurs due to gradual degeneration of retinal ganglion cells (RGCs).…”

Section: Introductionmentioning

confidence: 99%

Association of TGFB -509C>T promoter polymorphism with primary angle closure glaucoma in a North Indian Punjabi cohort

et al. 2021

View full text Add to dashboard Cite

Purpose Transforming growth factor beta (TGFB) is an important candidate gene implicated in glaucoma pathogenesis because it affects retinal ganglionic cell survival. The present study assessed the genetic association of -509C > T variant in the TGFB promoter region with primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG) in a North Indian Punjabi population. Method A total of 867 subjects (307 POAG, 133 PACG cases and 427 controls) were recruited from the targeted population. Genotyping was done by PCR-RFLP method and the data was analyzed using PLINK software (v1.07). Logistic regression under different genetic models was applied and genotype phenotype correlation was assessed by one-way ANOVA. Result A statistically significant difference in the frequency of heterozygotes among PACG cases (53.16%) and controls (30.07%) (p = 0.0002) was observed. Genetic model analysis revealed that mutant “TT” genotype conferred 2-fold risk towards PACG development under recessive model (p = 0.0019) while dominant model and co-dominant model provided 0.62 and 0.37 fold protection against PACG (p = 0.025 and p = 0.0001, respectively). Data segregation based on sex revealed a strong protective effect of heterozygous ‘CT’ genotype against progression of PACG among females (p = 0.002, OR = 0.37, 95% CI = 0.19–0.70), but conferred 2.14-fold risk among female POAG subjects (p = 0.013). Conclusion The study revealed a strong genetic association of -509C > T variant in TGFB with PACG in females. There is a need to replicate the results in a larger PACG cohort in other populations and further assess the contribution of sex specific factors in modifying genetic susceptibility to PACG.

show abstract

Primary Open Angle Glaucoma: The Pathophysiolgy, Mechanisms, Future Diagnostic and Therapeutic Directions

Cited by 4 publications

References 46 publications

Optic Disc and Vessel Segmentation in Retinal Images using Correlation Texture

Optic Disc and Vessel Segmentation in Retinal Images using Correlation Texture

Correlation of Intraocular Pressure and Random Blood Glucose Level in Patients with Primary Open-Angle Glaucoma

Association of TGFB -509C>T promoter polymorphism with primary angle closure glaucoma in a North Indian Punjabi cohort

Contact Info

Product

Resources

About