Association of progressive optic disc tilt with development of retinal nerve fibre layer defect in children with large cup-to-disc ratio

Background/aimsWhereas myopic optic disc deformation has been posited as a risk factor for glaucomatous damage, longitudinal studies evaluating their association have been sparse. We investigated whether the optic nerve head (ONH)’s morphological alteration during myopia progression play any role in development of retinal nerve fibre layer defect (RNFLD) in children with a large vertical cup-to-disc ratio (vCDR).MethodsSixty-five normotensive eyes of 65 children aged under 8 years with (1) vCDR ≥0.5 but no additional signs of glaucoma and (2) who could be tracked at young adulthood (18–28 years) were included. Children’s spherical equivalent (SE), intraocular pressure, vCDR and optic disc tilt ratio were recorded. Rare events logistic regression analysis was employed to identify factors associated with RNFLD-development risk.ResultsThe study group’s mean age was 5.4±1.3 years, its average vCDR was 0.62±0.07, and the average SE was −0.3±1.4 dioptres ((D), range −3.15 to 2.75D) at the baseline. After an average follow-up of 16.1±3.0 years, the mean vCDR was 0.64±0.09, and the mean SE, −3.2±2.2D (range −7.25 to 0.00 D). Among the 65 eyes, 12 (18.5%) developed RNFLD. A greater SE change (OR=1.737, p=0.016) and a greater increase in tilt ratio (OR=2.364, p=0.002) were both significantly associated with higher RNFLD-development risk.ConclusionIn this cohort of Korean children with large vCDR, progressive optic disc tilt in the course of myopia progression was associated with higher RNFLD-development risk. This finding suggests that morphological alterations in the ONH during axial elongation might represent an underlying susceptibility to glaucomatous damage in large-vCDR children.

An Efficient Deep Learning Approach to Automatic Glaucoma Detection Using Optic Disc and Optic Cup Localization

Glaucoma is an eye disease initiated due to excessive intraocular pressure inside it and caused complete sightlessness at its progressed stage. Whereas timely glaucoma screening-based treatment can save the patient from complete vision loss. Accurate screening procedures are dependent on the availability of human experts who performs the manual analysis of retinal samples to identify the glaucomatous-affected regions. However, due to complex glaucoma screening procedures and shortage of human resources, we often face delays which can increase the vision loss ratio around the globe. To cope with the challenges of manual systems, there is an urgent demand for designing an effective automated framework that can accurately identify the Optic Disc (OD) and Optic Cup (OC) lesions at the earliest stage. Efficient and effective identification and classification of glaucomatous regions is a complicated job due to the wide variations in the mass, shade, orientation, and shapes of lesions. Furthermore, the extensive similarity between the lesion and eye color further complicates the classification process. To overcome the aforementioned challenges, we have presented a Deep Learning (DL)-based approach namely EfficientDet-D0 with EfficientNet-B0 as the backbone. The presented framework comprises three steps for glaucoma localization and classification. Initially, the deep features from the suspected samples are computed with the EfficientNet-B0 feature extractor. Then, the Bi-directional Feature Pyramid Network (BiFPN) module of EfficientDet-D0 takes the computed features from the EfficientNet-B0 and performs the top-down and bottom-up keypoints fusion several times. In the last step, the resultant localized area containing glaucoma lesion with associated class is predicted. We have confirmed the robustness of our work by evaluating it on a challenging dataset namely an online retinal fundus image database for glaucoma analysis (ORIGA). Furthermore, we have performed cross-dataset validation on the High-Resolution Fundus (HRF), and Retinal Image database for Optic Nerve Evaluation (RIM ONE DL) datasets to show the generalization ability of our work. Both the numeric and visual evaluations confirm that EfficientDet-D0 outperforms the newest frameworks and is more proficient in glaucoma classification.

Pseudoexfoliation Glaucoma and its Systemic Association: A Clinical Study

Pseudoexfoliation [PXF] being a age related elastotic process is a well known entity among all ophthalmologists. PXF is most common form of secondary glaucoma. Objective: To study the clinical presentations and response to treatment of PXF glaucoma and also to throw light on its systemic associations. Methods: A total of 70 eyes of PXF glaucoma was considered for the study in duration of 6 months from june to November 2021 at a tertiary care center. All patients underwent detailed ophthalmic evaluation along with gonioscopy, optic disc assessment, visual fields and intraocular pressure. Based on all these , patients were graded as mild, moderate and advanced glaucoma and treated accordingly either with medical or surgical line of management. Patients were followed up for a duration of 6 months. ECG, echocardiography and dermatological evaluation of all the patients were done. Results: Mean age of 70 patients was 52.2 years and there was male preponderance .Powdery greyish white pseudoexfoliative material on pupillary margin was seen in 41 eyes[58.5%] and on anterior capsule was seen in 19 eyes[27.1%]. IOP in these 70 patients ranged between 14 to 40mmHg. Gonioscopy showed exfoliative material deposition in 14 eyes[20%] and increased pigmentation of trabecular meshwork in 44 eyes[62.85%]. Also, it revealed narrow angle( grade 1&2) in 6 eyes and open angle (grade 3&4) in rest .Visual filed changes were present in 57 of 70 eyes with PXF glaucoma. Optic disc changes in PXF glaucoma also showed variations with 17 eyes having CD ratio of<0.5,while 38 eyes had a cupping between 0.6-0.8. Eleven eyes showed advanced cupping of >0.8 while 4 eyes had glaucomatous optic atrophy.60 eyes were treated with medical line while 10 eyes were managed surgically. 4 patients had dermal nodules and diastolic dysfunction was noted in 31 patients. Conclusion: PXF confers a significantly higher risk of developing glaucoma in comparison with the general population and needs close monitering. PXF glaucoma and its systemic associations also has to be considered Keywords: PXF, pseudoexfoliative, ECG

Experimental Models of Glaucoma

Optic nerve pits are a mono- or bilateral congenital anomaly represented by optic disc depressions of various sizes. In half of the cases, the pits are complicated by edema, central retinal detachment and retinoschisis, and cause visual function decrease. Visual acuity losses can be either insignificant or pronounced. Optic discs pits have been investigated massively over the last century and a half, but their etiology is still underresearched. In recent years, however, due to the development of digital scanning and data processing technologies and the emergence of non-invasive highly informative diagnostic methods, it has become possible to reveal structural and functional changes of the optic disc in vivo, in addition to the traditional detection of histological changes in cadaveric eyes.Glaucomatous process modeling is one of the challenges in ophthalmology. And this is due primarily to the fact that, so far, the main reasons for the onset and progression of glaucoma. Numerous works on experimental research in its core model ocular. However, there are forms of glaucoma, which are independent of the level of intraocular pressure. Ideal model of glaucoma is considered a model with the development of the characteristic symptom in which a key symptom is a slowly progressive excavation of the optic nerve. But given the new knowledge in the pathogenesis of neurodegenerative changes in glaucoma in this model should be added and the opportunity to study the brain, vascular factors of progression, the level of neurotransmitters, trophic factors, etc. Therefore, we tried to make the analysis of models of glaucoma in various experimental animals and determine the most appropriate model for studying the pathogenesis of glaucoma.