All

Koo EH, Pineda R, Afshari N, Eghrari A. Learning Descemet Membrane Endothelial Keratoplasty: A Survey of U.S. Corneal Surgeons. Cornea 2020;39(5):590-593.Abstract
PURPOSE: The transition to Descemet membrane endothelial keratoplasty (DMEK) is frequently challenging, requiring the adoption of new techniques, skills, and methods. We sought to draw on surgeons' initial experiences with DMEK to characterize the learning curve associated with this procedure and identify factors that could be linked to the frequency of primary graft failure (PGF) in the first 10 cases. METHODS: We invited corneal surgeons based in the United States who started performing the DMEK procedure within the past 2 years to answer a 12-question survey using an online survey platform. We analyzed quantitative and qualitative data. A Fisher exact test was used to determine whether preoperative approaches to preparation were associated with decreased PGF rates. RESULTS: A total of 100 US-based corneal surgeons replied from 34 of 50 states. Of these, 68% reported that DMEK comprised a majority of their endothelial keratoplasty cases. Approximately half of surgeons (52%) had performed more than 20 DMEK cases by the time of the survey, and 51% felt equally comfortable performing DMEK relative to Descemet stripping endothelial keratoplasty. Among the respondents, 37% answered that they had experienced PGF in the first 10 cases. Scrubbing in with an experienced colleague before surgery was associated with a decreased likelihood of at least one case of PGF (31%, P = 0.049), but not participation in a wet lab with an experienced instructor or mentor (38%, P = 0.50), nor having an eye bank representative present in the operating room (43%, P = 0.886). CONCLUSIONS: The collective experience of 100 surgeons beginning DMEK confirms the importance of mentorship and that the accompaniment of an experienced colleague during the learning curve is associated with lower rates of PGF.
Bakshi SK, Graney J, Paschalis EI, Agarwal S, Basu S, Iyer G, Liu C, Srinivasan B, Chodosh J. Design and Outcomes of a Novel Keratoprosthesis: Addressing Unmet Needs in End-Stage Cicatricial Corneal Blindness. Cornea 2020;39(4):484-490.Abstract
PURPOSE: The most commonly applied prosthetic devices for corneal blindness in the setting of severe cicatricial keratoconjunctivitis are the Boston keratoprosthesis type II and the modified osteo-odonto-keratoprosthesis, with these requiring either normal eyelid skin or a healthy cuspid tooth, respectively. For patients with neither attribute, we developed a new keratoprosthesis device combining positive aspects of both Boston keratoprosthesis type II and modified osteo-odonto-keratoprosthesis, which we have named the "Lux." METHODS: Short-term postoperative outcomes for the Lux keratoprosthesis, best-corrected visual acuity (BCVA), device retention, and complications, were examined in a retrospective case series of 9 eyes of 9 patients implanted at 4 centers. RESULTS: Seven of 9 (77.8%) eyes had cicatricial corneal blindness due to autoimmune disease and 2 (22.2%) from severe burns. Preoperative BCVA was ≤hand motions in all patients. Three (33.3%) had previously received at least 1 keratoprosthesis in the affected eye, and 4 (44.4%) had previously undergone ≥1 therapeutic keratoplasty. One patient had 19 previous eye surgeries. The mean duration of postoperative follow-up was 18.7 months (range 7-28 months). BCVA of ≥20/200 was achieved in all 9 patients, with 2 (22.2%) reaching 20/20 at the last examination, and all 9 (100%) of the devices were retained. One recipient developed a retinal detachment 2 months after implantation. Two (22.2%) patients required placement of a glaucoma drainage device. CONCLUSIONS: The Lux keratoprosthesis was developed for patients with severe cicatricial keratoconjunctivitis who were otherwise not candidates for existing keratoprosthesis designs. Short-term outcomes after implantation of the Lux keratoprosthesis were encouraging.
Shakhmantsir I, Dooley SJ, Kishore S, Chen D, Pierce E, Bennett J, Sehgal A. RNA Splicing Factor Mutations That Cause Retinitis Pigmentosa Result in Circadian Dysregulation. J Biol Rhythms 2020;35(1):72-83.Abstract
Circadian clocks regulate multiple physiological processes in the eye, but their requirement for retinal health remains unclear. We previously showed that Drosophila homologs of spliceosome proteins implicated in human retinitis pigmentosa (RP), the most common genetically inherited cause of blindness, have a role in the brain circadian clock. In this study, we report circadian phenotypes in murine models of RP. We found that mice carrying a homozygous H2309P mutation in () display a lengthened period of the circadian wheel-running activity rhythm. We show also that the daily cycling of circadian gene expression is dampened in the retina of H2309P mice. Surprisingly, molecular rhythms are intact in the eye cup, which includes the retinal pigment epithelium (RPE), even though the RPE is thought to be the primary tissue affected in this form of RP. Downregulation of , another RNA splicing factor implicated in RP, leads to period lengthening in a human cell culture model. The period of circadian bioluminescence in primary fibroblasts of human RP patients is not significantly altered. Together, these studies link a prominent retinal disorder to circadian deficits, which could contribute to disease pathology.
Pineles SL, Aakalu VK, Hutchinson AK, Galvin JA, Heidary G, Binenbaum G, VanderVeen DK, Lambert SR. Binocular Treatment of Amblyopia: A Report by the American Academy of Ophthalmology. Ophthalmology 2020;127(2):261-272.Abstract
PURPOSE: To review the published literature assessing the efficacy of binocular therapy for the treatment of amblyopia compared with standard treatments. METHODS: Literature searches with no date restrictions and limited to the English language were conducted in January 2018 and updated in April 2019 in the PubMed database and the Cochrane Library database with no restrictions. The search yielded 286 citations, and the full text of 50 articles was reviewed. Twenty articles met the inclusion criteria for this assessment and were assigned a level of evidence rating by the panel methodologist. Six studies were rated level I, 1 study was rated level II, and 13 studies were rated level III because of the impact on the development and popularization of this technology. RESULTS: Two of the level I and II studies reviewed described a significant improvement in visual acuity in the binocular group versus standard patching standard treatment (the total number of patients in these 2 studies was 147). However, the 5 studies that failed to show a visual improvement from binocular therapy compared with standard treatments were larger and more rigorously designed (the total number of patients in these 5 studies was 813). Level I and II studies also failed to show a significant improvement over baseline in sensory status, including depth of suppression and stereopsis of those treated with binocular therapy. Several smaller level III case series (total number of patients in these 13 studies was 163) revealed more promising results than the binocular treatments studied in the level I and II studies, especially using treatments that are more engaging and are associated with better compliance. CONCLUSIONS: There is no level I evidence to support the use of binocular treatment as a substitute for current therapies for amblyopia (including patching and optical treatment). Furthermore, 2 large randomized controlled trials showed inferior performance compared with standard patching treatment. On the basis of this review of the published literature, binocular therapy cannot be recommended as a replacement for standard amblyopia therapy. However, more research is needed to determine the potential benefits of proposed binocular treatments in the future.
Gaier ED, Tarabishy S, Bayers C, Wolkow N, Gardiner M, Lefebvre DR, Grob S. Poor prognoses of open globe injuries with concomitant orbital fractures. Orbit 2020;39(4):241-250.Abstract
PURPOSE: Orbital trauma, particularly with open globe injury, can have a wide range of visual outcomes, which can be difficult to predict at presentation. Clinical features on presentation may provide insight into visual prognosis. We hypothesized that patients with open globe injuries and concomitant orbital fractures have poorer visual outcomes than patients without orbital fractures. METHODS: We reviewed the charts of 77 patients with isolated open globe injuries (OG) and 76 patients with open globe injuries and concomitant orbital fractures (OGOF). Multivariate regression analysis was performed to assess the relative influence of individual presenting historical and clinical features on visual outcome. RESULTS: OGOF patients were more likely to have sustained blunt trauma than a sharp, penetrating injury compared to OG patients. Ocular wound locations were more posterior and likely to involve multiple zones in OGOF compared to OG patients. Among OGOF patients, orbital floor fractures were the most common and roof fractures were the least common, but the latter was associated with presenting NLP vision and multiple zone involvement. The presence of an orbital fracture independently increased the odds of subsequent evisceration/enucleation (OR: 4.6, 95% CI 1.3-20.1, = .0246) and NLP vision (OR: 6.81, 95% CI 2.42-21.85, = .0005) when controlling for zone, mechanism of injury, uveal prolapse and demographic variables. CONCLUSIONS: The presence of an orbital fracture independently confers a worse visual and ocular prognosis in patients with open globe injuries. Patients with open globe injuries in this category should be appropriately counseled.
Coco G, Foulsham W, Nakao T, Yin J, Amouzegar A, Taketani Y, Chauhan SK, Dana R. Regulatory T cells promote corneal endothelial cell survival following transplantation via interleukin-10. Am J Transplant 2020;20(2):389-398.Abstract
The functional competence of corneal endothelial cells (CEnCs) is critical for survival of corneal allografts, but these cells are often targets of the immune response mediated by graft-attacking effector T cells. Although regulatory T cells (Tregs) have been studied for their role in regulating the host's alloimmune response towards the graft, the cytoprotective function of these cells on CEnCs has not been investigated. The aim of this study was to determine whether Tregs suppress effector T cell-mediated and inflammatory cytokine-induced CEnC death, and to elucidate the mechanism by which this cytoprotection occurs. Using 2 well-established models of corneal transplantation (low-risk and high-risk models), we show that Tregs derived from low-risk graft recipients have a superior capacity in protecting CEnCs against effector T cell-mediated and interferon-γ and tumor necrosis factor-α-induced cell death compared to Tregs derived from high-risk hosts. We further demonstrate that the cytoprotective function of Tregs derived from low-risk hosts occurs independently of direct cell-cell contact and is mediated by the immunoregulatory cytokine IL-10. Our study is the first to report that Tregs provide cytoprotection for CEnCs through secretion of IL-10, indicating potentially novel therapeutic targets for enhancing CEnC survival following corneal transplantation.
Zantut PRA, Veras MM, Yariwake VY, Takahashi WY, Saldiva PH, Young LH, Damico FM, Fajersztajn L. Effects of cannabis and its components on the retina: a systematic review. Cutan Ocul Toxicol 2020;39(1):1-9.Abstract
Cannabis is the most prevalent drug in the world and its consumption is growing. Cannabinoid receptors are present in the human central nervous system. Recent studies show evidence of the effects of cannabinoids on the retina, and synthesising the results of these studies may be relevant for ophthalmologists. Thus, this review adopts standardised, systematic review methodology to investigate the effects of exposure to cannabis and components on the retina. We searched five online databases for the combined terms for outcome ("retina") and exposure ("cannabis"). Eligibility of studies were conducted by two independent reviewers, and risk of bias was assessed. We retrieved 495 studies, screened 229 studies, assessed 52 studies for eligibility, and included 16 studies for qualitative analysis. The cannabinoids most frequently investigated were delta-9-tetrahydrocannabinol (THC), abnormal cannabidiol, synthetic cannabinoid, and cannabidiol (CDB). The outcomes most studied were neuroretinal dysfunction, followed by vascular effects. The studies also included investigation of neuroprotective and anti-inflammatory effects and teratogenic effects. This review suggests that cannabinoids may have an important role in retinal processing and function.
Choquet H, Wiggs JL, Khawaja AP. Clinical implications of recent advances in primary open-angle glaucoma genetics. Eye (Lond) 2020;34(1):29-39.Abstract
Over the last decade, genetic studies, including genome-wide association studies (GWAS), have accelerated the discovery of genes and genomic regions contributing to primary open-angle glaucoma (POAG), a leading cause of irreversible vision loss. Here, we review the findings of genetic studies of POAG published in English prior to September 2019. In total, 74 genomic regions have been associated at a genome-wide level of significance with POAG susceptibility. Recent POAG GWAS provide not only insight into global and ethnic-specific genetic risk factors for POAG susceptibility across populations of diverse ancestry, but also important functional insights underlying biological mechanisms of glaucoma pathogenesis. In this review, we also summarize the genetic overlap between POAG, glaucoma endophenotypes, such as intraocular pressure and vertical cup-disc ratio (VCDR), and other eye disorders. We also discuss approaches recently developed to increase power for POAG locus discovery and to predict POAG risk. Finally, we discuss the recent development of POAG gene-based therapies and future strategies to treat glaucoma effectively. Understanding the genetic architecture of POAG is essential for an earlier diagnosis of this common eye disorder, predictive testing of at-risk patients, and design of gene-based targeted medical therapies none of which are currently available.
Cheung CSY, Mireskandari K, Ali A, Silverman E, Tehrani N. Earlier use of systemic immunosuppression is associated with fewer ophthalmic surgeries in paediatric non-infectious uveitis. Br J Ophthalmol 2020;104(7):938-942.Abstract
BACKGROUND/AIMS: There is a paucity of large trials investigating the effect of management strategies for paediatric non-infectious uveitis on complications requiring surgery. The purpose of our study is to investigate whether earlier initiation of systemic immunosuppression in paediatric non-infectious uveitis is associated with fewer ophthalmic surgeries. METHODS: A retrospective review was conducted on 48 children with non-infectious uveitis assessed in 1998-2013. Patients were divided into uveitis diagnosed before December 2008 (group 1) and after January 2009 (group 2). Duration from uveitis onset to methotrexate initiation (U-MTX) and biological addition (U-Biologic) were reviewed. Follow-up visits with topical corticosteroids >3 times daily and active uveitis (≥1+ cells) during 3.5 years were documented. The main outcome measure was the need for ≥1 ophthalmic surgery at 3.5 years. RESULTS: In group 1, 69.5% of patients required ≥1 ophthalmic surgery at 3.5 years versus 26.9% in group 2 (p=0.005). U-MTX was 28.9±11.8 weeks and 14.2±10.0 weeks for groups 1 and 2 (p=0.028). U-Biologic was 134.6±46.0 weeks and 82.3±43.3 weeks for groups 1 and 2 (p=0.0016). Corticosteroid use >3 times daily was 85.9±52.7 weeks and 14.6±11.1 weeks for groups 1 and 2. Multivariate regression showed methotrexate initiation within 6 months of uveitis onset lowered the likelihood of needing ophthalmic surgery at 3.5 years (OR=6.2, 95% CI 1.2 to 33.4; p=0.033). Univariate regression demonstrated biological addition within 18 months of uveitis onset reduced the likelihood of requiring ophthalmic surgery (OR 12.57, 95% CI 1.28 to 123.48; p=0.030). CONCLUSION: Earlier control of uveitis by addition of immunosuppressive therapy reduced the need for ophthalmic surgery.
Porporato N, Baskaran M, Tun TA, Sultana R, Tan M, Quah JHM, Allen JC, Perera S, Friedman DS, Cheng CY, Aung T. Understanding diagnostic disagreement in angle closure assessment between anterior segment optical coherence tomography and gonioscopy. Br J Ophthalmol 2020;104(6):795-799.Abstract
BACKGROUND/AIMS: Although being a more objective tool for assessment and follow-up of angle closure, reliability studies have reported a moderate diagnostic performance for anterior segment optical coherence tomography (OCT) technologies when comparing with gonioscopy as the reference standard. We aim to determine factors associated with diagnostic disagreement in angle closure when assessed by anterior segment swept source OCT (SS-OCT, CASIA SS-1000; Tomey, Nagoya, Japan) and gonioscopy. METHODS: Cross-sectional study. A total of 2027 phakic subjects aged ≥50 years, with no relevant previous ophthalmic history, were consecutively recruited from a community polyclinic in Singapore. Gonioscopy and SS-OCT (128 radial scans) for the entire circumference of the angle were performed for each subject. A two-quadrant closed gonioscopic definition was used. On SS-OCT images, angle closure was defined as iridotrabecular contact (ITC) to the extent of ≥35%, ≥50% and ≥75% of the circumferential angle. Diagnostic disagreements between both methods, that is, false positives or overcalls and false negatives or undercalls were defined, respectively, as gonioscopic open/closed angles inversely assessed as closed/open by SS-OCT. RESULTS: Two hundred and seventy-two (14.7%) resulted in overcall results (false positives) when ≥50% of the angle circumference was closed using SS-OCT. These eyes had significantly wider (anterior chamber width, 11.7 vs 11.6 mm, p<0.001) and deeper (anterior chamber depth (ACD), 2.4 vs 2.2 mm, p<0.001) anterior chambers than eyes assessed by both methods as closed (true positives). Deeper ACD (OR 9.31) and lower lens vault (LV) (OR 0.04) were significantly associated with a false positive diagnosis in the multivariate analysis. Most of these cases had short (52.6%) or irregular (39%) ITC in SS-OCT images. CONCLUSIONS: We found that anterior chamber dimensions, determined by ACD and LV, were factors significantly associated with diagnostic disagreement between anterior segment SS-OCT and gonioscopy in angle closure assessment.
Mayro EL, Wang M, Elze T, Pasquale LR. The impact of artificial intelligence in the diagnosis and management of glaucoma. Eye (Lond) 2020;34(1):1-11.Abstract
Deep learning (DL) is a subset of artificial intelligence (AI), which uses multilayer neural networks modelled after the mammalian visual cortex capable of synthesizing images in ways that will transform the field of glaucoma. Autonomous DL algorithms are capable of maximizing information embedded in digital fundus photographs and ocular coherence tomographs to outperform ophthalmologists in disease detection. Other unsupervised algorithms such as principal component analysis (axis learning) and archetypal analysis (corner learning) facilitate visual field interpretation and show great promise to detect functional glaucoma progression and differentiate it from non-glaucomatous changes when compared with conventional software packages. Forecasting tools such as the Kalman filter may revolutionize glaucoma management by accounting for a host of factors to set target intraocular pressure goals that preserve vision. Activation maps generated from DL algorithms that process glaucoma data have the potential to efficiently direct our attention to critical data elements embedded in high throughput data and enhance our understanding of the glaucomatous process. It is hoped that AI will realize more accurate assessment of the copious data encountered in glaucoma management, improving our understanding of the disease, preserving vision, and serving to enhance the deep bonds that patients develop with their treating physicians.

Pages