Risk factors for progression to blindness in high tension primary open angle glaucoma: Comparison of blind and nonblind subjects

Karanjit S Kooner1, Mohannad AlBdoor1, Byung J Cho3, Beverley Adams-Huet21Department of Ophthalmology, 2Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas, USA; 3Konkuk University Hospital, Seoul, KoreaAims: To determine which risk factors for blindness were most critical in patients diagnosed with high tension primary open angle glaucoma (POAG) in a large ethnically diverse population managed with a uniform treatment strategy.Methods: A longitudinal observational study was designed to follow 487 patients (974 eyes) with POAG for an average of 5.5 ± 3.6 years. Detailed ocular and systemic information was collected on each patient and updated every six months. For this study, blindness was defined as visual acuity of 20/200 or worse and/or visual field less than 20° in either eye. Known risk factors were compared between patients with blindness in at least one eye versus nonblind patients.Results: The patients with blindness had on average: higher intraocular pressure (IOP, mmHg): (24.2 ± 11.2 vs. 22.1 ± 7.7, p = 0.03), wide variation of IOP in the follow-up period (5.9 vs. 4.1 mmHg, p = 0.031), late detection (p = 0.006), poor control of IOP (p < 0.0001), and noncompliance (p < 0.0003). Other known risk factors such as race, age, myopia, family history of glaucoma, history of ocular trauma, hypertension, diabetes, vascular disease, smoking, alcohol abuse, dysthyoidism, and steroid use were not significant.Conclusions: The most critical factors associated with the development of blindness among our patients were: elevated initial IOP, wide variations and poor control of IOP, late detection of glaucoma, and noncompliance with therapy.Keywords: primary open angle glaucoma, blindness, intraocular pressure, risk factors, and noncomplianc

The Role of Optical Coherence Tomography Angiography in Glaucoma

Glaucoma is the second leading cause of blindness worldwide, affecting eighty million people globally and three million patients in the USA. Primary open-angle glaucoma, the most common type, is a multifactorial progressive optic nerve neurodegenerative disorder that leads to loss of optic nerve head (ONH) tissue, thinning of the retinal nerve fiber layer, and corresponding visual field (VF) defects with or without elevated intraocular pressure (IOP). Risk factors include older age, black or Hispanic race, elevated IOP, thin central corneal thickness, disk hemorrhage, and low ocular perfusion pressure. The two prevalent theories explaining glaucomatous damage are mechanical (elevated IOP) and vascular (compromised optic nerve perfusion). Current diagnostic methods, such as measuring IOP, VF testing, and ONH evaluation, are subjective and often unreliable. Optical coherence tomography angiography (OCTA) is a rapid, non-invasive imaging modality that provides 3-D, volumetric details of both the structure and vascular networks of the retina and optic nerve. Various researchers have shown that OCTA provides an accurate and objective evaluation of the retina and the optic nerve in glaucoma. This chapter describes the role of OCTA in managing patients with glaucoma

Risk factors for legal blindness in primary open angle glaucoma

Context: POAG is a leading cause of irreversible blindness worldwide. Factors associated with the damage, progression of the disease and related blindness are poorly understood.;Objective: To determine characteristics of patients with POAG that are associated with either a higher risk for blindness or preservation of visual function.;Design: Prospective observational comparative cohort study.;Participants: In all, 487 (974 eyes) consecutive incoming patients with POAG were followed for 5.5 3.6 years. Exclusion criteria were l) secondary glaucoma, 2) ocular conditions that would interfere with proper diagnosis and management, and 3) less than 3 months follow-up.;Methods: Seventy-seven pieces of information were collected on each patient and updated at every six monthly visit. Comparisons were done between 1) patients with no legal blindness (NLB) and those with legal blindness (LB); 2) stable NLB patients and those who progressed; 3) the affected eye and non-affected eye of patients with unilateral blindness; and 4) initial presenting data of new patients.;Setting: Academic (Clinic A), county hospital (Clinic B), and a Veterans Affairs hospital (Clinic C) providing primary, secondary, and tertiary care.;Main Outcome Measures: 1) Development of legal blindness in one or both eyes and 2) progression of glaucoma in one or both eyes.;Results: Compared to NLB group, LB group features were: higher mean initial intraocular pressure (IOP), (p = 0.03), late detection (p = 0.006), wide variation of IOP in the follow-up period (5.9 vs 4.1 mmHg, p = 0.031), poor control of IOP (p < 0.0001) and non-compliance (p < 0.0003).;Conclusions: This study suggests that some of the risk factors for legal blindness in POAG are related to the level of initial IOP, late detection of the disease, poor control of IOP and non-compliance

Intraocular Surgery in Kyphosis: An Easier Approach

We describe a 49-year-old man with advanced kyphosis and dense cataract, who could only recline to about 40° from the vertical axis despite a maximal reverse Trendelenburg position and pillows under the head, neck, shoulders and knees. With a single corneal retraction suture at 6 o'clock, the eye could be rotated horizontally, which enabled the surgeon to perform a complex cataract surgery despite prior glaucoma shunt, posterior synechiae, a small pupil and the need to stain the capsule. As the eye can be brought into any desired position with a retraction suture, patients with kyphosis or other conditions that prevent them from assuming a supine position can still have safe intraocular procedures. This maneuver reduces the need to tilt patients to an uncomfortable position that may cause pain, increased breathing difficulty and elevated posterior vitreous pressure

Quantification of vascular morphology in optical coherence tomography angiography in primary open angle glaucoma

Purpose: To quantitatively measure and compare the vascular morphology in healthy eyes and eyes with primary open-angle glaucoma (POAG) using optical coherence tomography angiography (OCTA) scans. Methods: This is a retrospective and cross-sectional study which include healthy individuals and individuals with POAG that underwent OCTA imaging at an academic center's glaucoma clinic. We analyzed OCTA scans of the macula and optic nerve head (ONH) of one eye from each subject to quantitatively measure vessel density (VD), vessel length density (VLD), and branchpoint density (BPD). We compared these 3 parameters between the healthy and POAG groups and used logistic regression classification models to determine their diagnostic value in differentiating healthy and glaucomatous eyes. Results: We included 49 healthy subjects and 49 subjects with POAG. After age-adjusted analysis, the parameters of VD, VLD, and BPD were significantly reduced in eyes with POAG (P ​< ​0.001) in all scan layers and most significantly around the ONH. The parameter with the best performances were radial peripapillary capillary (RPC) VD [AUC (areas under the curve ): 0.939 (0.891, 0.987)] which had statistically higher performances (P ​< ​0.05) than parameters in the superficial or deep layers. All 3 parameters in the RPC layer had statistically similar performances. Conclusions: We found that VD, VLD, and BPD were reduced in glaucomatous eyes. The morphologic parameters of VLD and BPD had similar performances to the traditional parameter of VD in RPC layers. Our results suggest that vascular morphology parameters may provide additional value in the diagnosis and evaluation of glaucoma

The impact of the COVID-19 pandemic on early termination of ophthalmology clinical trials: A cross-sectional analysis of ClinicalTrials.gov

Objective: To study the effect of the COVID-19 pandemic on the early termination of ophthalmology clinical trials. Methods: On June 10, 2022, we searched ClinicalTrials.gov and identified clinical trials pertaining to eye diseases. We included trials last updated between January 1, 2020 and June 8, 2022, as ones possibly impacted by the pandemic. We selected all interventional trials in any stage and country that were “recruiting,” “active, not recruiting,” “enrolling by invitation,” “suspended,” “terminated,” “completed,” or “withdrawn” and excluded trials that had been completed or discontinued before 2020, had incomplete data, trials in which the eye was not the primary focus of the trial (e.g., Chediak-Higashi syndrome, myasthenia gravis). The following trial-level characteristics were collected: location, trial status, enrollment count, ocular condition, sponsors, intervention purpose, trial phase (I–IV), randomization, number of arms, and reasons for discontinuation. In addition to calculating descriptive statistics, we assessed whether trial characteristics differed between ophthalmology clinical trials canceled due to COVID-19 and those canceled for other reasons. Results: Following the screening, 2280/12,679 (18%) ophthalmology clinical trials were retained. Of these, 142 (6.2%) were discontinued between January 1, 2020 and June 8, 2022. Moreover, 34 out of 142 (23.9%) ophthalmology clinical trials were discontinued due to COVID-19. These trials were more likely to be sponsored by academic medical centers (26/34, 76.5% vs 57/108, 52.8%, p  = 0.03) and were not assigned to a specific study phase, indicating they were not investigational new drugs (22/34, 64.7% vs 46/108 42.6%, p  = 0.003). Conclusions: COVID-19-related trial discontinuations were more likely to be reported by academic medical centers and associated with trials investigating fully approved drugs, medical devices, procedures, diagnostic imaging, and behavioral changes. Further investigation of these characteristics may lead to a more robust and resilient understanding of the causes of early termination of these clinical trials