Generalizability of Deep Neural Networks for Vertical Cup-to-Disc Ratio Estimation in Ultra-Widefield and Smartphone-Based Fundus Images.

Purpose: To develop and validate a deep learning system (DLS) for estimation of vertical cup-to-disc ratio (vCDR) in ultra-widefield (UWF) and smartphone-based fundus images. Methods: A DLS consisting of two sequential convolutional neural networks (CNNs) to delineate optic disc (OD) and optic cup (OC) boundaries was developed using 800 standard fundus images from the public REFUGE data set. The CNNs were tested on 400 test images from the REFUGE data set and 296 UWF and 300 smartphone-based images from a teleophthalmology clinic. vCDRs derived from the delineated OD/OC boundaries were compared with optometrists' annotations using mean absolute error (MAE). Subgroup analysis was conducted to study the impact of peripapillary atrophy (PPA), and correlation study was performed to investigate potential correlations between sectoral CDR (sCDR) and retinal nerve fiber layer (RNFL) thickness. Results: The system achieved MAEs of 0.040 (95% CI, 0.037-0.043) in the REFUGE test images, 0.068 (95% CI, 0.061-0.075) in the UWF images, and 0.084 (95% CI, 0.075-0.092) in the smartphone-based images. There was no statistical significance in differences between PPA and non-PPA images. Weak correlation (r = -0.4046, P < 0.05) between sCDR and RNFL thickness was found only in the superior sector. Conclusions: We developed a deep learning system that estimates vCDR from standard, UWF, and smartphone-based images. We also described anatomic peripapillary adversarial lesion and its potential impact on OD/OC delineation. Translational Relevance: Artificial intelligence can estimate vCDR from different types of fundus images and may be used as a general and interpretable screening tool to improve community reach for diagnosis and management of glaucoma.

Ocular Toxoplasmosis.

INTRODUCTION: Ocular toxoplasmosis is the leading cause of posterior uveitis worldwide, affecting individuals acrossdifferent age groups. The key to reducing vision loss includes prompt diagnosis and treatment. However, despite the prevalence of ocular toxoplasmosis, there has been little consensus regarding its pathophysiology,clinical features, diagnosis, and especially management. METHODS: The data sources were literature reviews, including Pub Med and Medline databases. Search terms included toxoplasmosis, retinitis, vasculitis, vitritis, uveitis alone or in combination with, serum, aqueous, vitreous eye, ocular and review. RESULTS: In this review paper, we have sought to provide an overview of the pathophysiology, epidemiology, and clinical features of the disease, both based on current literature and our own clinical experience. We have also discussed the use of serology, ocular fluid, and ophthalmic investigations that could further facilitate the diagnosis of ocular toxoplasmosis.Different management strategies have been reported worldwide, including newer approaches such as local therapy. CONCLUSION: A better understanding of critical aspects of ocular toxoplasmosis will hopefully lead to reduced morbidity, including blindness associated with this condition.

An Unusual Case of Concurrent Central Retinal Vein and Cilioretinal Artery Occlusion in a Healthy Patient.

It is rare for young, healthy patients to have retinal venous or arterial occlusions and even rarer for both to occur in concert. Such an occurrence should prompt a rapid and extensive workup to prevent further complications. We present our patient, a 37-year-old Lebanese male, who reported a 3-day history of blurring of vision in his left eye. He had no medical or ocular history and is a nonsmoker. Examination of the left fundus revealed inferior macular edema and retinal whitening associated with tortuous retinal veins. He was diagnosed with a combined central retinal vein and cilioretinal artery occlusion. Emergency treatment was done for an acute arterial occlusion. Embolic and thrombotic causes were excluded with investigations. The only positive result was homozygosity for 677C>T mutation of the 5,10 methylenetetrahydrofolate reductase (MTHFR) enzyme gene. MTHFR enzyme breaks down homocysteine, which is atherogenic and prothrombotic. This mutation can lead to a prothrombotic state, precipitating this occurrence. In fact, the Lebanese population is known to have the highest incidence of such mutations, but there are surprisingly few reports on retinal vascular occlusions attributed to this. He was promptly treated with antiplatelet therapy, possibly preventing a full-blown central retinal vein occlusion. After 4 weeks, his vision improved to 6/6 bilaterally. Examination showed less tortuous veins, no more retinal whitening, resolution of macula edema and visual field defect. Hyperhomocysteinemia can be significant in patients without ischemic risk factors. It is vital to manage these patients promptly, preventing future sight and life-threatening events.

Impact of prophylactic intracameral moxifloxacin on post-cataract surgery endophthalmitis: data from a tertiary eye care facility in rural India.

PURPOSE: To study the impact of prophylactic intracameral (IC) moxifloxacin on the incidence, clinical profile and outcomes in eyes developing post-cataract surgery endophthalmitis (PCE). METHODS: This was a single-centre, retrospective, comparative, observational study in which all eyes with PCE between June 2013 and May 2014 without IC moxifloxacin prophylaxis (group A) and June 2015-May 2016 with IC moxifloxacin prophylaxis (group B) were analysed. RESULTS: A total of 101,815 cataract surgeries were performed in group A and 112,967 in group B. PCE was diagnosed in 179 eyes (0.18%) in group A and 92 eyes (0.08%) in group B (p < 0.001). Greater reduction in risk of PCE was seen in subsidised patients compared to private. The presenting and final visual acuity was significantly better in group B (p < 0.05). CONCLUSIONS: Prophylactic IC moxifloxacin reduced the incidence of PCE with maximum benefit being observed for the subsidised patients and also helped achieve a significantly better visual acuity following the resolution of endophthalmitis.

Publisher Correction: A Simplified, Graded, Electrodiagnostic Criterion for Guillain-Barré Syndrome That Incorporates Sensory Nerve Conduction Studies.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A Simplified, Graded, Electrodiagnostic Criterion for Guillain-Barré Syndrome That Incorporates Sensory Nerve Conduction Studies.

Traditional electrodiagnostic (EDX) criteria for Guillain-Barré Syndrome (GBS), e.g. those delineated by Ho et al. and Hadden et al., rely on motor nerve conduction studies (NCS), and focus on differentiating GBS subtypes instead of the accurate diagnosis of GBS. Sensory studies, including the sural-sparing pattern, are not routinely used in GBS EDX. We studied the utility of a simplified criterion that utilizes sensory NCS. Motor and sensory NCS abnormalities were defined by comparing against age and height adjusted norms derived from 245 controls. We considered the sural-sparing pattern a positive diagnostic feature. We analyzed 109 prospectively validated GBS patients and graded them as "Definite", "Probable" and "Possible" based on the number of motor and sensory abnormalities detected. Using proposed EDX criteria, 35.8%, 43.1%, 11.9% of all GBS patients were considered "Definite", "Probable" or "Possible" respectively; whereas traditional EDX criteria only diagnosed 49.5% of cases. 27.5%, 35.3% and 21.6% of patients with the Miller-Fisher Syndrome (MFS) subtype of GBS were considered "Definite", "Probable" or "Possible" respectively. In comparison, traditional criteria only detected 15.7% of cases. Our proposed EDX criterion, that includes sensory NCS, improves and grades the diagnostic certainty of GBS, especially MFS.