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1.
Exp Eye Res ; : 109909, 2024 May 04.
Article En | MEDLINE | ID: mdl-38710357

Neovascular age-related macular degeneration, also known as exudative or wet age-related macular degeneration, is the leading cause of blindness in the developed world. Photobiomodulation has the potential to target the up-stream hypoxic and pro-inflammatory drivers of choroidal neovascularization. This study investigated whether photobiomodulation attenuates characteristic pathological features of choroidal neovascularization in a rodent model. Experimental choroidal neovascularization was induced in Brown Norway rats with laser photocoagulation. A custom-designed, slit-lamp-mounted, 670 nm laser was used to administer retinal photobiomodulation every 3 days, beginning 6 days prior to choroidal neovascularization induction and continuing until the animals were killed 14 days later. The effect of photobiomodulation on the size of choroidal neovascular membranes was determined using isolectin-B4 immunohistochemistry and spectral domain-optical coherence tomography. Vascular leakage was determined with fluorescein angiography. The effect of treatment on levels of vascular endothelial growth factor expression was quantified with enzyme-linked immunosorbent assay. Treatment with photobiomodulation was associated with choroidal neovascular membranes that were smaller, had less fluorescein leakage, and a diminished presence of inflammatory cells as compared to sham eyes. These effects were not associated with a statistically significant difference in the level of vascular endothelial growth factor when compared to sham eyes. The data shown herein indicate that photobiomodulation attenuates pathological features of choroidal neovascularization in a rodent model by mechanisms that may be independent of vascular endothelial growth factor.

2.
Surv Ophthalmol ; 2024 Apr 25.
Article En | MEDLINE | ID: mdl-38677557

Macular holes (MH) are full-thickness retinal defects affecting central vision. While vitrectomy with inner limiting membrane (ILM) peel is the conventional MH treatment, non-surgical alternatives are gaining interest to mitigate surgical risks. This study conducted a comprehensive literature review and analysis of non-surgical MH management. A systematic literature search was conducted on PubMed, Embase, Scopus, and the Cochrane Library from January 1, 1973, to September 13, 2023. Treatments included laser therapy, carbonic anhydrase inhibitors (CAIs), non-steroidal anti-inflammatories (NSAIDs), steroids (topical, subtenons, peribulbar, intravitreal), intravitreal gas, anti-vascular endothelial growth factors (VEGF) and ocriplasmin injections. Data extraction covered study details, patient characteristics, MH features, treatment outcomes, and recurrence rates. The initial search yielded 3,352 articles, refined to 83 articles which met inclusion criteria following screening. Overall reported anatomical closure rates were 36% with laser photocoagulation, 37% with intravitreal ocriplasmin, 55% with intravitreal gas. Closures were more frequently observed with topical NSAIDs (79%), steroids (84%) and CAIs (73%). Closures were more often observed in patients with smaller MH and in the presence of cystic macular oedema. Although non-surgical MH management approaches show potential for conservative therapy, evidence is limited to support routine use. Stage 1 and traumatic MH may benefit from a short period of observation but the gold standard approach for full-thickness MH remains to be vitrectomy with ILM peel.

3.
Biosci Rep ; 44(4)2024 Apr 24.
Article En | MEDLINE | ID: mdl-38567515

The complex metabolic relationship between the retinal pigment epithelium (RPE) and photoreceptors is essential for maintaining retinal health. Recent evidence indicates the RPE acts as an adjacent lactate sink, suppressing glycolysis in the epithelium in order to maximize glycolysis in the photoreceptors. Dysregulated metabolism within the RPE has been implicated in the pathogenesis of age-related macular degeneration (AMD), a leading cause of vision loss. In the present study, we investigate the effects of four cytokines associated with AMD, TNFα, TGF-ß2, IL-6, and IL-1ß, as well as a cocktail containing all four cytokines, on RPE metabolism using ARPE-19 cells, primary human RPE cells, and ex vivo rat eyecups. Strikingly, we found cytokine-specific changes in numerous metabolic markers including lactate production, glucose consumption, extracellular acidification rate, and oxygen consumption rate accompanied by increases in total mitochondrial volume and ATP production. Together, all four cytokines could potently override the constitutive suppression of glycolysis in the RPE, through a mechanism independent of PI3K/AKT, MEK/ERK, or NF-κB. Finally, we observed changes in glycolytic gene expression with cytokine treatment, including in lactate dehydrogenase subunit and glucose transporter expression. Our findings provide new insights into the metabolic changes in the RPE under inflammatory conditions and highlight potential therapeutic targets for AMD.


Macular Degeneration , Retinal Pigment Epithelium , Humans , Rats , Animals , Retinal Pigment Epithelium/metabolism , Metabolic Reprogramming , Cytokines/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Macular Degeneration/genetics , Macular Degeneration/metabolism , Lactates/metabolism
5.
Exp Neurol ; 371: 114610, 2024 01.
Article En | MEDLINE | ID: mdl-37944880

Hampering assessment of treatment outcomes in gene therapy and other clinical trials in patients with childhood dementia is the lack of an objective, non-invasive measure of neurodegeneration. Optical coherence tomography (OCT) is a widely available, rapid, non-invasive, and quantitative method for examining the integrity of the neuroretina. Profound brain and retinal dysfunction occur in patients and animal models of childhood dementia, including Sanfilippo syndrome and we recently revealed a correlation between the age of onset and rate of progression of retinal and brain degeneration in sulfamidase-deficient Sanfilippo mice. The aim of the current study was to use OCT to visualise the discrete changes in retinal structure that occur during disease progression. A progressive decline in retinal thickness was readily observable in Sanfilippo mice using OCT, with differences seen in affected animals from 10-weeks of age. OCT applied to i.v. AAV9-sulfamidase-treated Sanfilippo mice enabled visualisation of improved retinal anatomy in living animals, an outcome confirmed via histology. Importantly, brain disease lesions were also ameliorated in treated Sanfilippo mice. The findings highlight the sensitivity, ease of repetitive use and quantitative capacity of OCT for detection of discrete changes in retinal structure and their prevention with a therapeutic. Combined with the knowledge that retinal and brain degeneration are correlated in Sanfilippo syndrome, OCT provides a window to the brain in this and potentially other childhood dementias.


Dementia , Mucopolysaccharidosis III , Humans , Mice , Animals , Mucopolysaccharidosis III/diagnostic imaging , Mucopolysaccharidosis III/genetics , Mucopolysaccharidosis III/therapy , Retina/diagnostic imaging , Retina/pathology , Brain/diagnostic imaging , Brain/pathology , Genetic Therapy , Dementia/pathology , Disease Models, Animal
6.
Int Ophthalmol ; 43(12): 4487-4489, 2023 Dec.
Article En | MEDLINE | ID: mdl-37572167

PURPOSE: To determine whether Twitter improves dissemination of ophthalmology scientific publications METHODS: Data were collected on articles published on PubMed between the years 2016 and 2021 (inclusive) and identified with the word "ophthalmology". Twitter performance metrics, including the number of tweets, number of likes, and number of retweets were collected from Twitter using the publicly available scientific API. Machine learning and descriptive statistics were used to outline Twitter performance metrics. RESULTS: The number of included articles was 433710. The percentage of articles that were in the top quartile for citation count, which had ≥1 tweet was 34.4% (number 437/1270). Conversely, the percentage of articles that were in the top quartile for citation count, which had 0 tweets was 27.8% (number 12023/43244). When machine learning was used to predict Twitter performance metrics an AUROC of 0.78 was returned. This was associated with an accuracy of 0.97 CONCLUSION: This study has shown preliminary evidence to support that Twitter may improve the dissemination of scientific ophthalmology publications.


Ophthalmology , Social Media , Humans
7.
Clin Exp Ophthalmol ; 51(6): 577-584, 2023 08.
Article En | MEDLINE | ID: mdl-37221135

BACKGROUND: The accurate encoding of operation notes is essential for activity-based funding and workforce planning. The aim of this project was to evaluate the procedural coding accuracy of vitrectomy and to develop machine learning, natural language processing (NLP) models that may assist with this task. METHODS: This retrospective cohort study involved vitrectomy operation notes between a 21-month period at the Royal Adelaide Hospital. Coding of procedures were based on the Medicare Benefits Schedule (MBS)-the Australian equivalent to the Current Procedural Terminology (CPT®) codes used in the United States. Manual encoding was conducted for all procedures and reviewed by two vitreoretinal consultants. XGBoost, random forest and logistic regression models were developed for classification experiments. A cost-based analysis was subsequently conducted. RESULTS: There were a total of 1724 procedures with individual codes performed within 617 vitrectomy operation notes totalling $1 528 086.60 after manual review. A total of 1147 (66.5%) codes were missed in the original coding that amounted to $736 539.20 (48.2%). Our XGBoost model had the highest classification accuracy (94.6%) in the multi-label classification for the five most common procedures. The XGBoost model was the most successful model in identifying operation notes with two or more missing codes with an AUC of 0.87 (95% CI 0.80-0.92). CONCLUSIONS: Machine learning has been successful in the classification of vitrectomy operation note encoding. We recommend a combined human and machine learning approach to clinical coding as automation may facilitate more accurate reimbursement and enable surgeons to prioritise higher quality clinical care.


Electronic Health Records , Vitrectomy , Aged , Humans , Retrospective Studies , Australia , National Health Programs , Machine Learning
8.
Ophthalmology ; 130(8): 830-836, 2023 08.
Article En | MEDLINE | ID: mdl-37044160

PURPOSE: To assess the association between a glaucoma polygenic risk score (PRS) and treatment outcomes in primary open-angle glaucoma. DESIGN: Prospective, observational cohort study. PARTICIPANTS: Participants from the Progression Risk of Glaucoma: Relevant SNPs with Significant Association Study were divided into a cohort with suspect glaucoma who were treatment naive at enrollment and one with early manifest and suspect glaucoma receiving treatment at enrollment. METHODS: A per-allele weighted glaucoma PRS was calculated for 1107 participants. Multivariable mixed-effects Cox proportional regression analysis assessed the association between PRS and time to commencement of intraocular pressure (IOP)-lowering therapy in 416 patients with suspect glaucoma who were treatment naive at study enrollment. Secondary analysis evaluated the association between PRS and escalation of IOP-lowering therapy among 691 patients with suspect and early manifest glaucoma who were receiving IOP-lowering therapy at enrollment. MAIN OUTCOME MEASURES: Commencement or escalation of IOP-lowering therapy. RESULTS: A higher PRS was associated with a greater risk of commencing IOP-lowering therapy within 5 years (hazard ratio [HR], 1.45 per 1 standard deviation [/SD]; 95% confidence interval [CI], 1.27-1.62; P < 0.001). Participants in the upper population-based quintile showed a 3.3 times greater risk of commencing therapy by 5 years than those in the lowest quintile (HR, 3.30; 95% CI, 1.63-6,70; P < 0.001) and a 5.4 times greater risk of commencing IOP-lowering therapy by 2 years than the those in the lowest quintile (HR, 5.45; 95% CI, 2.08-14.25; P < 0.001). A higher PRS was associated with a greater risk of treatment escalation among patients receiving treatment at enrollment (HR, 1.19/SD; 95% CI, 1.09-1.31; P < 0.001). In combined analysis of all participants, participants in the top population-based quintile were at 2.3 times greater risk of requiring initiation or escalation of IOP-lowering therapy than those in the lowest quintile (HR, 2.33; 95% CI, 1.75-3.01; P < 0.001). CONCLUSIONS: This study demonstrated novel associations between glaucoma polygenic risk and risk of commencement or escalation of IOP-lowering therapy, building on previous work highlighting the potential clinical usefulness of genetic risk stratification in glaucoma. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Glaucoma, Open-Angle , Glaucoma , Ocular Hypertension , Humans , Glaucoma, Open-Angle/drug therapy , Glaucoma, Open-Angle/genetics , Prospective Studies , Intraocular Pressure , Ocular Hypertension/drug therapy
9.
Invest Ophthalmol Vis Sci ; 64(3): 11, 2023 03 01.
Article En | MEDLINE | ID: mdl-36867133

Purpose: To assess the association between physical activity and spectral-domain optical coherence tomography (SD-OCT)-measured rates of macular thinning in an adult population with primary open-angle glaucoma. Methods: The correlation between accelerometer-measured physical activity and rates of macular ganglion cell-inner plexiform layer (GCIPL) thinning was measured in 735 eyes from 388 participants of the Progression Risk of Glaucoma: RElevant SNPs with Significant Association (PROGRESSA) study. The association between accelerometer-measured physical activity and cross-sectional SD-OCT macular thickness was then assessed in 8862 eyes from 6152 participants available for analysis in the UK Biobank who had SD-OCT, ophthalmic, comorbidity, and demographic data. Results: Greater physical activity was associated with slower rates of macular GCIPL thinning in the PROGRESSA study (beta = 0.07 µm/y/SD; 95% confidence interval [CI], 0.03-0.13; P = 0.003) after adjustment for ophthalmic, demographic and systemic predictors of macular thinning. This association persisted in subanalyses of participants characterized as glaucoma suspects (beta = 0.09 µm/y/SD; 95% CI, 0.03-0.15; P = 0.005). Participants in the upper tertile (greater than 10,524 steps/d) exhibited a 0.22-µm/y slower rate of macular GCIPL thinning than participants in the lower tertile (fewer than 6925 steps/d): -0.40 ± 0.46 µm/y versus -0.62 ± 0.55 µm/y (P = 0.003). Both time spent doing moderate/vigorous activity and mean daily active calories were positively correlated with rate of macular GCIPL thinning (moderate/vigorous activity: beta = 0.06 µm/y/SD; 95% CI, 0.01-0.105; P = 0.018; active calories: beta = 0.06 µm/y/SD; 95% CI, 0.006-0.114; P = 0.032). Analysis among 8862 eyes from the UK Biobank revealed a positive association between physical activity and cross-sectional total macular thickness (beta = 0.8 µm/SD; 95% CI, 0.47-1.14; P < 0.001). Conclusions: These results highlight the potential neuroprotective benefits of exercise on the human retina.


Glaucoma, Open-Angle , Glaucoma , Adult , Humans , Cross-Sectional Studies , Retina , Exercise
10.
Eye (Lond) ; 37(1): 62-68, 2023 01.
Article En | MEDLINE | ID: mdl-35001090

OBJECTIVES: To establish cultures of human lacrimal gland from patient-derived, biopsy-sized, tissue specimens. METHODS: Tissue was obtained after surgical removal from patients without dry eye disease undergoing routine procedures. Samples were subjected to mechanical and enzymatic digestion and resulting cell suspensions were plated onto collagen-coated glass coverslips and grown for up to 21 days. Cultures were analysed by immunocytochemistry and light microscopy, and resultant cellular distributions were compared to those in sections of fixed human lacrimal gland tissue. RESULTS: Dissociation of biopsy-sized pieces of human lacrimal gland and seeding onto coated surfaces allowed development of a mixed population of cells in vitro. Within 7-14 days, cellular aggregation was observed and by 21 days many cells had organised themselves into distinct three-dimensional complexes. Immunohistochemistry revealed a heterogeneous population of cells, including epithelial, myoepithelial, mesenchymal and progenitor cells. Some of the epithelia labelled positively for lysozyme and lactoferrin. CONCLUSIONS: Collection and dissociation of biopsy-sized pieces of human lacrimal gland leads to a cellular preparation that can proliferate in vitro and organise into three-dimensional structures. This is the first report detailing that biopsy-collected specimens of human lacrimal gland can be used to establish cell cultures.


Lacrimal Apparatus , Humans , Cells, Cultured , Epithelial Cells/metabolism , Immunohistochemistry , Biopsy
11.
Eye (Lond) ; 37(6): 1139-1144, 2023 04.
Article En | MEDLINE | ID: mdl-35505111

BACKGROUND/OBJECTIVES: To evaluate current routine trabeculectomy technique preferences among Australian and New Zealand Glaucoma Society surgeons regularly performing trabeculectomy surgery. SUBJECTS/METHODS: Survey of experienced surgeons who perform trabeculectomy. RESULTS: Forty-nine surgeons (33 male:16 female) participated in the survey. Trabeculectomy was performed as day surgery (39/47, 83.0%) under local anesthesia (44/47, 93.6%). The surgical techniques most commonly used were a corneal traction suture (44/47, 93.6%), fornix-based conjunctival flap (43/47, 91.5%) and half-thickness scleral flap (38/47, 81.0%). Mitomycin C antifibrotic agent was used in routine cases by 45/46 (97.8%) surgeons. Surgeons applied the antifibrotic agent under the Tenon layer with a pledget (36/46, 78.2%) with a concentration of 0.02% (37/46, 80.4%) for 2 (11/46, 23.9%) or 3 min (30/46, 65.2%). The Kelly (26/46, 56.5%) and the Khaw Descemet (19/46, 41.3%) punches were used to perform the sclerostomy. Most surgeons performed a peripheral iridectomy in all phakic patients (46/47, 97.9%), but less commonly in pseudophakic patients (34/47, 72.3%). Techniques for closure of the limbal conjunctival edge were quite varied with a combination of suturing including purse string (21/47, 57.4%), wing (20/47, 42.6%) and horizontal mattress sutures (33/47, 70.2%). Surgeons reviewed their routine patients four times in the first month (29/47, 61.7%) and continued the postoperative topical steroids for 3-4 months (28/47, 59.6%). CONCLUSIONS: Although a wide range of techniques for trabeculectomy exists among surgeons, there are consistent procedures currently in use to optimize patient outcomes. This report will assist surgeons in choosing which surgical techniques fit their best practice.


Glaucoma , Surgeons , Trabeculectomy , Humans , Male , Female , Trabeculectomy/methods , New Zealand , Australia , Glaucoma/surgery , Mitomycin , Intraocular Pressure , Suture Techniques , Retrospective Studies
12.
Br J Ophthalmol ; 107(8): 1178-1183, 2023 08.
Article En | MEDLINE | ID: mdl-35354562

AIMS: To determine the prevalence and causes of visual impairment and blindness in Vientiane Province, the Lao People's Democratic Republic (Lao PDR). METHODS: We conducted a population-based, cross-sectional study of 1264 participants aged 40 years and older from urban and rural areas of Vientiane Province. The ophthalmic examination included presenting and pinhole Snellen visual acuity (VA) with an illiterate E chart, slit-lamp examination of the anterior segment and dilated stereoscopic fundus examination. Visual impairment and blindness were defined by both presenting and pinhole VA based on the better eye according to WHO criteria: VA worse than 6/12 to 6/18 for mild impairment, VA worse than 6/18 to 6/60 for moderate impairment, VA worse than 6/60 to 3/60 for severe impairment and VA worse than 3/60 for blindness. RESULTS: Comprehensive ophthalmic examinations were performed on 1264 participants (77.8% participation rate). Population-weighted prevalence of presenting bilateral blindness was 1.4% (95% CI 0.8 to 2.0) and bilateral visual impairment was 22.4% (95% CI 14.7 to 30.1). After pinhole correction, the corresponding prevalence of blindness was 1.3% (95% CI 0.8 to 2.0) and that of visual impairment was 12.6% (95% CI 8.2 to 16.9). Cataract was the leading cause of presenting bilateral blindness (52.9%), whereas uncorrected refractive error was the predominant cause of presenting visual impairment (40.3%). CONCLUSIONS: Visual impairment and blindness remain major public health problems in Lao PDR. There is an ongoing need to fund ophthalmic care resources and community education programmes to improve access to healthcare in this region.


Vision Disorders , Adult , Humans , Middle Aged , Age Distribution , Blindness/epidemiology , Blindness/etiology , Blindness/diagnosis , Cataract/complications , Cataract/epidemiology , Cross-Sectional Studies , Laos/epidemiology , Prevalence , Rural Population , Vision Disorders/diagnosis , Vision Disorders/epidemiology , Vision Disorders/etiology , Vision Disorders/therapy , Vision, Low/epidemiology , Vision, Low/etiology , Vision, Low/diagnosis , Visually Impaired Persons/statistics & numerical data , Refractive Errors/complications , Refractive Errors/epidemiology
13.
Can J Ophthalmol ; 58(5): 461-464, 2023 10.
Article En | MEDLINE | ID: mdl-35640671

OBJECTIVE: To determine normal globe position values, interzygomatic distance (IZD), and globe axial length and width on computed tomography in an Australian cohort. DESIGN: Retrospective cohort study. PARTICIPANTS: Patients who underwent computed tomography of the orbits. Patients with bilateral disease, previous orbital surgery, or poor scan quality were excluded. METHODS: An axial slice through the midglobe was used to conduct the globe position measurements. Anterior globe position was defined as the perpendicular distance from the anterior globe margin to the interzygomatic line and posterior globe position as the perpendicular distance from the posterior globe margin to the interzygomatic line. RESULTS: The normal measurements (mean ± SD) were IZD, 97.4 ± 4.1 mm; anterior globe position, 18.8 ± 2.8 mm; posterior globe position, 6.2 ± 2.9 mm; axial globe length, 24.9 ± 1.1 mm; and axial globe width, 25.9 ± 1.2 mm. A significant positive correlation was seen between the IZD and the anterior globe position (r = 0.15, p = 0.03), axial globe length (r = 0.33, p < 0.01), and axial globe width (r = 0.30, p < 0.01). CONCLUSION: This normative globe position data may be used to diagnose radiologic exophthalmos or enophthalmos.


Orbit , Tomography, X-Ray Computed , Humans , Retrospective Studies , Australia , Orbit/diagnostic imaging , Tomography, X-Ray Computed/methods
14.
Am J Ophthalmol ; 245: 126-133, 2023 01.
Article En | MEDLINE | ID: mdl-35970205

PURPOSE: To evaluate the relationship between body mass index (BMI) and glaucoma progression. DESIGN: Multicohort observational study. METHODS: This study combined a retrospective longitudinal analysis of suspect and early manifest primary open angle glaucoma cases from the Progression Risk of Glaucoma: RElevant SNPs with Significant Association (PROGRESSA) study with 2 replication cohorts from the UK Biobank and the Canadian Longitudinal Study of Ageing (CLSA). In the PROGRESSA study, multivariate analysis correlated BMI with longitudinal visual field progression in 471 participants. The BMI was then associated with glaucoma diagnosis and cross-sectional vertical cup-disc ratio (VCDR) measurements in the UK Biobank, and finally prospectively associated with longitudinal change in VCDR in the CLSA study. RESULTS: In the PROGRESSA study, a lower BMI conferred a faster rate of visual field progression (mean duration of monitoring (5.28 ± 1.80 years (10.6 ± 3.59 visits) (ß 0.04 dB/year/SD95% CI [0.005, 0.069]; P = .013). In the UK Biobank, a 1 standard deviation lower BMI was associated with a worse cross-sectional VCDR (ß -0.048/SD 95% CI [-0.056, 0.96]; P < .001) and a 10% greater likelihood of glaucoma diagnosis, as per specialist grading of retinal fundus imaging (OR 0.90 95% CI [0.84, 0.98]; P = .011). Similarly, a lower BMI was associated with a greater risk of glaucoma diagnosis as per International Classification of Disease data (OR 0.94/SD; 95% CI [0.91, 0.98]; P = .002). Body mass index was also positively correlated with intraocular pressure (ß 0.11/SD; 95% CI [0.06, 0.15]; P < .001). Finally, a lower BMI was then associated with greater VCDR change in the CLSA (ß -0.007/SD; 95% CI [-0.01, -0.001]; P = .023). CONCLUSIONS: Body mass index correlated with longitudinal and cross-sectional glaucomatous outcomes. This supports previous work illustrating a correlation between BMI and glaucoma.


Glaucoma, Open-Angle , Glaucoma , Optic Disk , Humans , Glaucoma, Open-Angle/diagnosis , Glaucoma, Open-Angle/epidemiology , Body Mass Index , Retrospective Studies , Cross-Sectional Studies , Longitudinal Studies , Canada , Intraocular Pressure , Glaucoma/diagnosis
15.
Front Cell Neurosci ; 16: 1036834, 2022.
Article En | MEDLINE | ID: mdl-36467607

Retinal detachment is a sight-threatening disorder, which occurs when the photoreceptors are separated from their vascular supply. The aim of the present study was to shed light on photoreceptor energy metabolism during experimental detachment in rats. Retinal detachment was induced in the eyes of rats via subretinal injection of sodium hyaluronate. Initially, we investigated whether detachment caused hypoxia within photoreceptors, as evaluated by the exogenous and endogenous biomarkers pimonidazole and HIF-1α, as well as by qPCR analysis of HIF target genes. The results showed no unequivocal staining for pimonidazole or HIF-1α within any detached retina, nor upregulation of HIF target genes, suggesting that any reduction in pO2 is of insufficient magnitude to produce hypoxia-induced covalent protein adducts or HIF-1α stabilisation. Subsequently, we analysed expression of cellular bioenergetic enzymes in photoreceptors during detachment. We documented loss of mitochondrial, and downregulation of glycolytic enzymes during detachment, indicating that photoreceptors have reduced energetic requirements and/or capacity. Given that detachment did not cause widespread hypoxia, but did result in downregulated expression of bioenergetic enzymes, we hypothesised that substrate insufficiency may be critical in terms of pathogenesis, and that boosting metabolic inputs may preserve photoreceptor bioenergetic production and, protect against their degeneration. Thus, we tested whether supplementation with the bioavailable energy substrate pyruvate mitigated rod and cone injury and degeneration. Despite protecting photoreceptors in culture from nutrient deprivation, pyruvate failed to protect against apoptotic death of rods, loss of cone opsins, and loss of inner segment mitochondria, in situ, when evaluated at 3 days after detachment. The regimen was also ineffective against cumulative photoreceptor deconstruction and degeneration when evaluated after 4 weeks. Retinal metabolism, particularly the bioenergetic profiles and pathological responses of the various cellular subtypes still presents a considerable knowledge gap that has important clinical consequences. While our data do not support the use of pyruvate supplementation as a means of protecting detached photoreceptors, they do provide a foundation and motivation for future research in this area.

16.
Asia Pac J Ophthalmol (Phila) ; 11(6): 549-553, 2022 Nov 01.
Article En | MEDLINE | ID: mdl-36417680

Intraocular visualization in cataract surgery is currently achieved using the ophthalmic surgical microscope (OSM). Three-dimensional (3D) heads-up display is a burgeoning intraocular visualization technique for cataract surgery, which projects the surgical view to a 3D monitor. A number of theoretical advantages of this system over the OSM have been proposed. 3D visualization is reported to provide improved depth perception and the heads-up display promotes a more ergonomic surgical position while providing an enhanced view for the entire surgical team. The modern OSMs, however, already allow for safe and efficient cataract surgery, and 3D heads-up display visualization is limited by a steep learning curve. We critically review the literature around 3D heads-up display cataract surgery and compare its safety profile to traditional visualization techniques.


Cataract Extraction , Cataract , Ophthalmology , Humans
17.
Transl Vis Sci Technol ; 11(11): 10, 2022 11 01.
Article En | MEDLINE | ID: mdl-36374486

Purpose: The purpose of this study was to determine whether rodent lacrimal glands (LGs) represent a suitable surrogate for human tissue in bio-engineering research, we undertook a meticulous histological and histochemical comparison of these two tissues. Methods: Histological techniques and immunohistochemistry were used to compare the structure of adult human and rat LG tissues and the expression of key functional tissue elements. Results: Compared with humans, the rat LG is comprised of much more densely packed acini which are devoid of an obvious central lumen. Myoepithelial, fibroblasts, dendritic cells, T cells, and putative progenitor cells are present in both tissues. However, human LG is replete with epithelium expressing cytokeratins 8 and 18, whereas rat LG epithelium does not express cytokeratin 8. Furthermore, human LG expresses aquaporins (AQPs) 1, 3, and 5, whereas rat LG expresses AQPs 1, 4, and 5. Additionally, mast cells were identified in the rat but not the human LGs and large numbers of plasma cells were detected in the human LGs but only limited numbers were present in the rat LGs. Conclusions: The cellular composition of the human and rat LGs is similar, although there is a marked difference in the actual histo-architectural arrangement of the tissue. Further variances in the epithelial cytokeratin profile, in tissue expression of AQPs and in mast cell and plasma cell infiltration, may prove significant. Translational Relevance: The rat LG can serve as a useful surrogate for the human equivalent, but there exist specific tissue differences meaning that caution must be observed when translating results to patients.


Aquaporins , Lacrimal Apparatus , Humans , Adult , Rats , Animals , Lacrimal Apparatus/chemistry , Lacrimal Apparatus/metabolism , Lacrimal Apparatus/pathology , Stem Cells , Aquaporins/analysis , Aquaporins/metabolism , Epithelium , Bioengineering
18.
JAMA Ophthalmol ; 2022 Nov 10.
Article En | MEDLINE | ID: mdl-36355370

Importance: Irreversible vision loss from primary open-angle glaucoma (POAG) can be prevented through timely diagnosis and treatment, although definitive diagnosis can be difficult in early-stage disease. As a consequence, large numbers of individuals with suspected glaucoma require regular monitoring, even though many of these may never develop disease and other high-risk individuals with suspected glaucoma may have delayed or inadequate treatment. POAG is one of the most heritable common diseases, and this provides an opportunity to use genetic instruments in risk-stratified screening, diagnosis, and treatment of early glaucoma. Objective: To assess the association of glaucoma polygenic risk with glaucoma progression in early-stage disease. Design, Setting, and Participants: This cohort study used clinical and genetic data obtained from a longitudinal cohort study, Progression Risk of Glaucoma: Relevant SNPs With Significant Association (PROGRESSA). Participants of European ancestry with characteristic optic nerve head changes suggestive of glaucoma were included. Data were collected between February 2012 and June 2020. Analysis took place between July 2020 and April 2022. Main Outcomes and Measures: The association of a glaucoma polygenic risk score (PRS) (2673 uncorrelated variants) with rate of peripapillary retinal nerve fiber layer thinning on optical coherence tomography and progression of visual field loss on 24-2 Humphrey visual fields. Results: A total of 1777 eyes from 896 individuals had sufficient data for structural progression analyses and 1563 eyes from 808 individuals for functional progression analyses. The mean (SD) age was 62.1 (9.9) years, 488 (44%) were male, and 1087 of 1103 individuals (98.5%) had European ancestry. An ancestrally matched normative population cohort (n = 17 642) was used for PRS reference. Individuals in the top 5% PRS risk group were at a higher risk of visual field progression compared with the remaining 95% after 5 years (hazard ratio, 1.5; 95% CI, 1.13-1.97; P = .005). Conversely, those in the bottom 20% PRS risk group were at a lower risk of visual field progression compared with an intermediate risk group over 3 years (hazard ratio, 0.52; 95% CI, 0.28-0.96; P = .04). Conclusions and Relevance: In this study, high polygenic risk was associated with more rapid structural and functional progression in early POAG, despite more intensive treatment. A PRS may serve as a valuable adjunct to identify individuals who stand to benefit the most from more frequent surveillance and earlier or more intensive treatment.

19.
Clin Exp Ophthalmol ; 50(7): 709-710, 2022 09.
Article En | MEDLINE | ID: mdl-36226517
20.
Lancet Glob Health ; 10(12): e1754-e1763, 2022 12.
Article En | MEDLINE | ID: mdl-36240807

BACKGROUND: In 2021, WHO Member States endorsed a global target of a 40-percentage-point increase in effective refractive error coverage (eREC; with a 6/12 visual acuity threshold) by 2030. This study models global and regional estimates of eREC as a baseline for the WHO initiative. METHODS: The Vision Loss Expert Group analysed data from 565 448 participants of 169 population-based eye surveys conducted since 2000 to calculate eREC (met need/[met need + undermet need + unmet need]). A binary logistic regression model was used to estimate eREC by Global Burden of Disease (GBD) Study super region among adults aged 50 years and older. FINDINGS: In 2021, distance eREC was 79·1% (95% CI 72·4-85·0) in the high-income super region; 62·1% (54·7-68·8) in north Africa and Middle East; 49·5% (45·0-54·0) in central Europe, eastern Europe, and central Asia; 40·0% (31·7-48·2) in southeast Asia, east Asia, and Oceania; 34·5% (29·4-40·0) in Latin America and the Caribbean; 9·0% (6·5-12·0) in south Asia; and 5·7% (3·1-9·0) in sub-Saharan Africa. eREC was higher in men and reduced with increasing age. Global distance eREC increased from 2000 to 2021 by 19·0%. Global near vision eREC for 2021 was 20·5% (95% CI 17·8-24·4). INTERPRETATION: Over the past 20 years, distance eREC has increased in each super region yet the WHO target will require substantial improvements in quantity and quality of refractive services in particular for near vision impairment. FUNDING: WHO, Sightsavers, The Fred Hollows Foundation, Fondation Thea, Brien Holden Vision Institute, Lions Clubs International Foundation.


Global Health , Refractive Errors , Adult , Male , Humans , Middle Aged , Aged , Global Burden of Disease , Africa South of the Sahara , Europe , Refractive Errors/epidemiology , Refractive Errors/therapy
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