The objective of this study was to evaluate which hyperelastic model could best describe the non-linear mechanical behavior of the cornea, in order to characterize the capability of the non-linear model parameters to discriminate structural changes in a damaged cornea. Porcine corneas were used, establishing two different groups: control (non-treated) and NaOH-treated (damaged) corneas (n = 8). NaOH causes a chemical burn to the corneal tissue, simulating a disease associated to structural damage of the stromal layer. Quasi-static uniaxial tensile tests were performed in nasal-temporal direction immediately after preparing corneal strips from the two groups. Three non-linear hyperelastic models (i.e. Hamilton-Zabolotskaya model, Ogden model and Mooney-Rivlin model) were fitted to the stress-strain curves obtained in the tensile tests and statistically compared. The corneas from the two groups showed a non-linear mechanical behavior that was best described by the Hamilton-Zabolotskaya model, obtaining the highest coefficient of determination (R > 0.95). Moreover, Hamilton-Zabolotskaya model showed the highest discriminative capability of the non-linear model parameter (Parameter A) for the tissue structural changes between the two sample groups (p = 0.0005). The present work determines the best hyperelastic model with the highest discriminative capability in description of the non-linear mechanical behavior of the cornea.
PURPOSE: To compare the clinical characteristics and in vivo confocal microscopy (IVCM) findings of patients with neuropathic corneal pain (NCP) due to refractive surgery (RS-NCP) and herpetic eye disease (H-NCP) to controls. METHODS: Sixteen patients with RS-NCP and 7 patients with H-NCP, and 37 healthy reference age- and sex-matched healthy controls were included to the study. The medical records were reviewed for demographic features, detailed disease history, ocular surface disease index (OSDI), ocular pain assessment survey (OPAS) scores. IVCM images of patients were analyzed and compared to reference controls by two masked observers. RESULTS: The mean pain intensity score for the last 24 h (5.1 ± 2.4 vs. 3.9 ± 1.2; p = 0.27), last 2 weeks (6.1 ± 2.5 vs. 4.8 ± 2.3; p = 0.13) for RS-NCP vs. H-NCP respectively, and quality of life scores (p = 0.23) were similar in both groups. Quality of life, especially mood (p = 0.06) and enjoying life/relations to others (p = 0.10) were affected in both groups, but were not statistically significant between groups. The mean total nerve density was lower in RS-NCP (5702.4 ± 4599.0 μm/mm) compared to their respective controls (26,422.8 ± 4491.0; p < 0.001) and in the H-NCP group (2149.5 ± 2985.9) compared to their respective controls (22,948.8 ± 3169.0; p < 0.001). Alterations in DC density were similar between all groups (38.3 ± 48.0 cells/mm in RS-NCP, 61.0 ± 76.9 in H-NCP, p = 0.95). CONCLUSION: Neuropathic corneal pain patients due to refractive surgery show similar clinical characteristics, pain levels, quality of life impact, and IVCM findings as patients with NCP due to herpetic eye disease.
Transcription factors (TFs) are often used repeatedly during development and homeostasis to control distinct processes in the same and/or different cellular contexts. Considering the limited number of TFs in the genome and the tremendous number of events that need to be regulated, re-use of TFs is necessary. We analyzed how the expression of the homeobox TF, orthodenticle homeobox 2 (Otx2), is regulated in a cell type- and stage-specific manner during development in the mouse retina. We identified seven -regulatory modules (CRMs), among which the O5, O7 and O9 CRMs mark three distinct cellular contexts of Otx2 expression. We discovered that Otx2, Crx and Sox2, which are well-known TFs regulating retinal development, bind to and activate the O5, O7 or O9 CRMs, respectively. The chromatin status of these three CRMs was found to be distinct in different retinal cell types and at different stages. We conclude that retinal cells use a cohort of TFs with different expression patterns and multiple CRMs with different chromatin configurations to regulate the expression of Otx2 precisely.
PURPOSE: To evaluate the association between Medicaid expansion and diabetic dilated eye examinations. DESIGN: A retrospective difference in differences (DiD) analysis using individual-level survey response data from January 1, 2009, to December 31, 2017. PARTICIPANTS: A total of 52 392 survey responses from 50 states and the District of Columbia between 2009 and 2017. Responders were adults aged 18 to 64 years reporting a previous diagnosis of diabetes and a household income below 138% of the US federal poverty line (FPL). METHODS: The Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System data were used to identify survey responders who were asked about the presence of dilated eye examinations from years before and after Medicaid expansion implementation. MAIN OUTCOME MEASURES: The DiD in proportion of dilated eye examinations among diabetic persons aged 18 to 64 years with household incomes below 138% of the FPL between states that did and did not implement Medicaid expansion. RESULTS: Implementation of Medicaid expansion policies was associated with a 1.3% (95% confidence interval [CI], -3.8 to 6.4; P = 0.61), 6.3% (95% CI, 1.3-11.3; P = 0.016), 4.1% (95% CI, -0.8 to 9.0; P = 0.11), and 2.3% (95% CI, -1.6 to 6.2; P = 0.23) increase in the proportion of diabetic persons aged 18 to 64 years with incomes below 138% of the FPL receiving a dilated eye examination within the past year due to Medicaid expansion 1, 2, 3, and 4 cumulative years after expansion, respectively. CONCLUSIONS: Medicaid expansion policies were significantly associated with an increase in dilated eye examination rates within the first 2 years after implementation. However, this increase did not persist beyond this period, with nonsignificant increases 3 and 4 cumulative years after implementation. Healthcare policymakers should be aware that additional measures beyond expanding insurance coverage may be necessary to increase and sustain the rate of dilated eye examinations among diabetic populations.
Chen JJ, Flanagan EP, Bhatti TM, Jitprapaikulsan J, Dubey D, Lopez Chiriboga ASS, Fryer JP, Weinshenker BG, McKeon A, Tillema J-M, Lennon VA, Lucchinetti CF, Kunchok A, McClelland CM, Lee MS, Bennett JL, Pelak VS, Van Stavern G, Adesina O-OO, Eggenberger ER, Acierno MD, Wingerchuk DM, Lam BL, Moss H, Beres S, Gilbert AL, Shah V, Armstrong G, Heidary G, Cestari DM, Stiebel-Kalish H, Pittock SJ. Steroid-sparing maintenance immunotherapy for MOG-IgG associated disorder. Neurology 2020;95(2):e111-e120.Abstract
OBJECTIVE: Myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG) associated disorder (MOGAD) often manifests with recurrent CNS demyelinating attacks. The optimal treatment for reducing relapses is unknown. To help determine the efficacy of long-term immunotherapy in preventing relapse in patients with MOGAD, we conducted a multicenter retrospective study to determine the rate of relapses on various treatments. METHODS: We determined the frequency of relapses in patients receiving various forms of long-term immunotherapy for MOGAD. Inclusion criteria were history of ≥1 CNS demyelinating attacks, MOG-IgG seropositivity, and immunotherapy for ≥6 months. Patients were reviewed for CNS demyelinating attacks before and during long-term immunotherapy. RESULTS: Seventy patients were included. The median age at initial CNS demyelinating attack was 29 years (range 3-61 years; 33% <18 years), and 59% were female. The median annualized relapse rate (ARR) before treatment was 1.6. On maintenance immunotherapy, the proportion of patients with relapse was as follows: mycophenolate mofetil 74% (14 of 19; ARR 0.67), rituximab 61% (22 of 36; ARR 0.59), azathioprine 59% (13 of 22; ARR 0.2), and IV immunoglobulin (IVIG) 20% (2 of 10; ARR 0). The overall median ARR on these 4 treatments was 0.3. All 9 patients treated with multiple sclerosis (MS) disease-modifying agents had a breakthrough relapse on treatment (ARR 1.5). CONCLUSION: This large retrospective multicenter study of patients with MOGAD suggests that maintenance immunotherapy reduces recurrent CNS demyelinating attacks, with the lowest ARR being associated with maintenance IVIG therapy. Traditional MS disease-modifying agents appear to be ineffective. Prospective randomized controlled studies are required to validate these conclusions.
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.
Fay A, Nallasamy N, Allen RC, Bernardini FP, Bilyk JR, Cockerham K, Cruz AA, Devoto M, Dolman PJ, Dutton JJ, Jordan DR, Kersten R, Kim Y-D, Lucarelli MJ, McNab AA, Mombaerts I, Mourits M, Nerad J, Perry JD, Rose G, Saeed P, Seah LL, Selva D, Sivak-Callcott J, Strianese D, Verity DH, Verity DH. Perioperative Prophylactic Antibiotics in 1,250 Orbital Surgeries. Ophthalmic Plast Reconstr Surg 2020;36(4):385-389.Abstract
PURPOSE: Intravenous antibiotic prophylaxis is used for many clean-contaminated surgeries or clean surgeries with an implant, but its value for clean orbital surgery has not been determined. This study investigated infection risks and adverse effects related to antibiotics in patients undergoing orbital surgery. METHODS: A prospective, nonrandomized comparative case series of all patients undergoing orbital surgery with participating surgeons between October 1, 2013, and March 1, 2015. Types of surgery, antibiotic regimens, corticosteroid use, antibiotic side effects, and surgical site infections (SSIs) were entered into an electronic database and subsequently analyzed. Cases in which patients received postoperative oral antibiotics were analyzed separately. RESULTS: Of 1,250 consecutive orbital surgeries, 1,225 met inclusion criteria. A total of 1208 patients were included in the primary analysis: 603 received no antibiotic prophylaxis (group A), and 605 received a single dose of intravenous antibiotic (group B). Five patients (0.42%) developed an SSI, 3 in group A and 2 in group B. The difference in SSI rates was not statistically significant between the 2 groups (p = 0.66). Antibiotic prophylaxis, alloplastic implants, paranasal sinus entry, and corticosteroid use were not associated with differences in SSI rates. All SSIs resolved on a single course of oral antibiotics; an implant was removed in 1 case. There were no complications associated with a single dose of intravenous prophylaxis. However, 12% of 17 patients (group C) who received 1 week of oral postoperative prophylactic antibiotics developed antibiotic-related complications (diarrhea, renal injury), yielding a number needed to harm of 8.5. CONCLUSIONS: In this large series, antibiotic prophylaxis does not appear to have reduced the already low incidence of SSI following orbital surgery. Given the detriments of systemic antibiotics, the rarity of infections related to orbital surgery, and the efficacy of treating such infections should they occur, patients undergoing orbital surgery should be educated to the early symptoms of postoperative infection and followed closely, but do not routinely require perioperative antibiotics.
The prevalence as well as the severity of dry eye disease increase with age. Memory T helper 17 (Th17) cells (CD4IL-17ACD44) drive the chronic and relapsing course of dry eye disease. Here, we investigated the contribution of memory Th17 cells to age-related dry eye disease, and evaluated memory Th17 cell depletion with anti-IL-15 antibody as a strategy to abrogate the severe exacerbations of dry eye disease observed in aged mice. After initial exposure to desiccating stress, aged mice maintained higher frequencies of memory Th17 cells in the draining lymph nodes relative to young mice. Upon secondary exposure to desiccating stress, aged mice developed more severe corneal epitheliopathy than young mice, which is associated with increased local frequencies of Th17 cells (CD4IL-17A). Treatment with anti-IL-15 antibody decreased the enlarged memory Th17 pool in aged mice to frequencies comparable with young mice. Furthermore, anti-IL-15-treated mice showed significantly reduced conjunctival infiltration of Th17 cells and lower corneal fluorescein staining scores compared with saline-treated control mice. Our data suggest that age-related increases in the memory Th17 compartment predispose aged mice toward the development of severe corneal epithelial disease after exposure to a dry environment. Selectively targeting memory Th17 cells may be a viable therapeutic approach in the treatment of age-related dry eye disease.
Shwachman-Diamond syndrome (SDS) is an autosomal recessive multisystem disorder characterized by exocrine pancreatic dysfunction, bone marrow failure, and leukemia predisposition. Approximately 90% of cases are due to biallelic mutations in the Shwachman-Bodian-Diamond (SBDS) gene. Additional phenotypic features variably associated with SDS include skeletal, neurologic, hepatic, cardiac, endocrine, and dental abnormalities. We report five subjects with SDS who developed a range of inflammatory manifestations. Three patients developed inflammatory eye conditions. Single cases of juvenile idiopathic arthritis, chronic recurrent multifocal osteomyelitis, and scleroderma were also noted. Clinical presentation and treatment responses are described. Proteomic analysis revealed increased inflammatory signatures in SDS subjects as compared to controls. Treatment of inflammatory manifestations in patients with SDS may be complicated by potential myelosuppressive toxicities of anti-rheumatic medications. Further research is needed to better understand the potential link between inflammatory disorders and SDS to inform effective treatment strategies.
The viral antigen (Ag)-specific CD8 cytotoxic T lymphocytes (CTLs) derived from pluripotent stem cells (PSCs), i.e., PSC-CTLs, have the ability to suppress hepatitis B virus (HBV) infection. After adoptive transfer, PSC-CTLs can infiltrate into the liver to suppress HBV replication. Nevertheless, the mechanisms by which the viral Ag-specific PSC-CTLs provoke the antiviral response remain to be fully elucidated. In this study, we generated the functional HBV surface Ag-specific CTLs from the induced PSC (iPSCs), i.e., iPSC-CTLs, and investigated the underlying mechanisms of the CTL-mediated antiviral replication in a murine model. We show that adoptive transfer of HBV surface Ag-specific iPSC-CTLs greatly suppressed HBV replication and prevented HBV surface Ag expression. We further demonstrate that the adoptive transfer significantly increased T cell accumulation and production of antiviral cytokines. These results indicate that stem cell-derived viral Ag-specific CTLs can robustly accumulate in the liver and suppress HBV replication through producing antiviral cytokines.
Fetal and early postnatal inflammation have been associated with increased morbidity in extremely preterm infants. This study aimed to demonstrate if postpartum levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) were associated with early inflammation. In a cohort of 90 extremely preterm infants, DHA and AA in cord blood, on the first postnatal day and on postnatal day 7 were examined in relation to early systemic inflammation, defined as elevated C-reactive protein (CRP) and/or interleukin-6 (IL-6) within 72 h from birth, with or without positive blood culture. Median serum level of DHA was 0.5 mol% (95% CI (confidence interval) 0.2-0.9, = 0.006) lower than the first postnatal day in infants with early systemic inflammation, compared to infants without signs of inflammation, whereas levels of AA were not statistically different between infants with and without signs of inflammation. In cord blood, lower serum levels of both DHA (correlation coefficient -0.40; = 0.010) and AA (correlation coefficient -0.54; < 0.001) correlated with higher levels of IL-6. Levels of DHA or AA did not differ between infants with and without histological signs of chorioamnionitis or fetal inflammation. In conclusion, serum levels of DHA at birth were associated with the inflammatory response during the early postnatal period in extremely preterm infants.
BACKGROUND: To investigate and contrast the prevalence of dry eye symptoms in construction workers and office workers using the OSDI questionnaire. METHODS: A cross-sectional, observational study was conducted using the OSDI questionnaire to evaluate dry eye symptoms and associated risk factors. Sampled size calculation with a power of 80% and a 95% degree of confidence suggested the inclusion of 298 participants. RESULTS: We studied 304 subjects (149 construction workers and 155 office workers). More than half (55%) of the participants presented dry eye symptoms (OSDI > 12). The average OSDI score was 21.30 ± 22.20 points, being lower in the group of construction workers (12.45 ± 17.50) than in-office workers (28.51 ± 22.99) (p < 0.001). Considering participants who had moderate and severe symptoms (23 to 100 points in OSDI), office workers presented dry eye symptoms 4.15 times more frequently than construction workers (OR 4.15, 95% CI 2.52, 6.85). Women presented statistical evidence of higher OSDI scores than men (32.47 ± 23.72 vs. 14.87 ± 18.48, respectively). CONCLUSIONS: construction workers have four times less risk of presenting dry eye symptoms than people working in the average office space. This highlights the pernicious effects on the ocular surface of the office environment, which poses a significant risk for the development or worsening of dry eye symptoms.
Artificial cornea is an effective treatment of corneal blindness. Yet, intraocular pressure (IOP) measurements for glaucoma monitoring remain an urgent unmet need. Here, we present the integration of a fiber-optic Fabry-Perot pressure sensor with an FDA-approved keratoprosthesis for real-time IOP measurements using a novel strategy based on optical-path self-alignment with micromagnets. Additionally, an alternative noncontact sensor-interrogation approach is demonstrated using a bench-top optical coherence tomography system. We show stable pressure readings with low baseline drift (<2.8 mm Hg) for >4.5 years in vitro and efficacy in IOP interrogation in vivo using fiber-optic self-alignment, with good initial agreement with the actual IOP. Subsequently, IOP drift in vivo was due to retroprosthetic membrane (RPM) formation on the sensor secondary to surgical inflammation (more severe in the current pro-fibrotic rabbit model). This study paves the way for clinical adaptation of optical pressure sensors with ocular implants, highlighting the importance of controlling RPM in clinical adaptation.
Disruption of retinal pigment epithelial (RPE) barrier integrity and RPE migration are hallmark features in neovascular age-related macular degeneration (nAMD), but the underlying causes and pathophysiology are not completely well-defined. Herein, we aimed to evaluate the effect of bone morphogenetic proteins (BMPs) on the barrier function and migration of RPE. In particular, we investigated the role of BMP2 and BMP4 in these processes as our analysis of RNA-sequencing (seq) data from human donor eyes demonstrated that they are highly differentially expressed BMP members in macular RPE/choroid versus macular retina. We used electrical cell-substrate impedance sensing (ECIS) system to monitor precisely in real time the barrier integrity and migration of ARPE-19 after treatment with various concentrations of BMP2 or BMP4. Immunofluorescence was also used to assess the changes in the expression and the organization of the key tight junction protein, zona occludens (ZO)-1, in ARPE-19 cells under BMP2 or BMP4 treatment. This was followed by measuring the activity of matrix metalloproteinases (MMPs). Finally, RNA-seq and ELISA were used to determine the local and circulating levels of BMP2 and BMP4 in retinas and serum samples from nAMD donors. Our ECIS results showed that BMP4 but not BMP2 decreased the transcellular electrical resistance (TER) of ARPE-19 and increased their migration in comparison with control (vehicle-treated cells). Furthermore, immunofluorescence showed a disorganization of ZO-1 in BMP4-treated ARPE-19 not in BMP2-treated cells or vehicle-treated controls. This effect of BMP4 was associated with significant increases in the activity of MMPs, specifically MMP2. Lastly, these results were corroborated by additional findings that circulating but not local BMP4 levels were significantly higher in nAMD donor samples compared to controls. Collectively, our results demonstrated unreported effects of BMP4 on inducing RPE dysfunction and suggest that BMP4 but not BMP2 may represent a potential therapeutic target in nAMD.
BACKGROUND: The COVID-19 pandemic has caused much morbidity and mortality to patients but also health care providers. AIMS: We tabulated the cases of physician deaths from COVID-19 associated with front-line work in hopes of mitigating future events. METHODS: On 15 April 2020, a Google internet search was performed using the keywords 'doctor', 'physician', 'death', 'COVID' and 'coronavirus' in English and Farsi, and Chinese using the Baidu search engine. The age, sex and medical speciality of physicians who died from COVID-19 in the line of duty were recorded. Individuals greater than 90 years of age were excluded. RESULTS: We found 278 physicians who died with COVID-19 infection, but complete details were missing for 108 individuals. The average age of the physicians was 63.7 years with a median age of 66 years, and 90% were male (235/261). General practitioners and emergency room doctors (108/254), respirologists (5/254), internal medicine specialists (13/254) and anaesthesiologists (6/254) comprised 52% of those dying. Two per cent of the deceased were epidemiologists (5/254), 2% were infectious disease specialists (4/254), 6% were dentists (16/254), 4% were ENT (9/254) and 3% were ophthalmologists (8/254). The countries with the most reported physician deaths were Italy (121/278; 44%), Iran (43/278; 15%), Philippines (21/278; 8%), Indonesia (17/278; 6%), China (16/278; 6%), Spain (12/278; 4%), USA (12/278; 4%) and UK (11/278;4%). CONCLUSIONS: Physicians from all specialities may die from COVID. Lack of personal protective equipment was cited as a common cause of death. Consideration should be made to exclude older physicians from front-line work.
PURPOSE: The objective of this article is to document a unique case of a primary hemangioma and review epibulbar vascular tumors of the conjunctiva and episclera. METHODS: A case report with detailed histopathologic, histochemical, and immunohistochemical studies coupled with a comprehensive review of the relevant literature with a tabulation of previously reported epibulbar vascular lesions was performed. RESULTS: A vascular tumor developed in a 46-year-old woman over 2-3 months that histopathologically was located in the superficial third of the normally avascular sclera and was composed of capillary caliber vessels. CD31 and CD34 positivity established the vascular nature of the lesion. Despite its adult onset, the tumor was also glut-1 positive, a vascular characteristic of childhood capillary hemangiomas that will ultimately involute. Smooth muscle actin was positive in the endothelial cells and associated pericytes. An ectatic muscular vessel identified in the midst of the lesion was interpreted as an anomalous intrascleral branch of an epibulbar anterior ciliary artery, where it perforated the sclera in the vicinity of the insertion of an extraocular rectus muscle. It was deduced to be the source of the capillary proliferation. A literature review failed to identify any previously reported epibulbar vascular tumor that originated primarily in the sclera or secondarily infiltrated this ocular tunic. CONCLUSION: An adult primary capillary intrascleral neoplasm is described as the rarest of all epibulbar vascular tumors and in keeping with the exceptional status of the ocular endothelium was glut-1 positive. This lesion must be distinguished from an array of other common and esoteric epibulbar vascular conditions.
PRECIS: A survey among members of the American Glaucoma Society (AGS) and the American Optometry Association (AOA) on tonometer preference and tonometer disinfection indicates a shift to disposable tonometer tips compared with 1987. PURPOSE: This survey's purpose was to determine how eye care providers responded to the 2008 Centers of Disease Control (CDC) tonometer disinfection guidelines, which recommend 10% hypochlorite (dilute bleach) for reusable tonometers. Tonometers measure the eye pressure when they touch the cornea, an essential part of the eye examination. METHODS: AGS and AOA members were surveyed on tonometer preference, tonometer use, disinfection process, disinfectants, disinfection timing, and tonometer damage. RESULTS: Survey responses from 79 AOA members and 197 AGS members are included. The Goldmann tonometer is considered most accurate (70, 89% AOA and 161, 82% AGS). It is preferred by 54 (70%) AOA and 193 (98%) AGS members. Many providers (165) use reusable Goldmann tonometer tips (77, 79% AOA, 88, 45% AGS), and most clean with 70% isopropyl alcohol wipes 59 (77%) AOA and 54 (61%) AGS. In summary, 126 of 276 participants (8, 10% AOA and 118, 60% AGS) follow CDC guidelines by using disposable tips (2 AOA and 109 AGS) or disinfecting reusable tips with 10% hypochlorite (6 AOA and 9 AGS). CONCLUSIONS: The majority of AGS providers follow current CDC tonometer disinfection guidelines by shifting to disposable Goldmann tonometer tips. Only a minority of providers who use reusable tonometer tips disinfect with dilute bleach. Continued education on proper tonometer disinfection is critical to prevent eye-care related infection due to improper disinfection.
We have developed a deep learning-based computer algorithm to recognize and predict retinal differentiation in stem cell-derived organoids based on bright-field imaging. The three-dimensional "organoid" approach for the differentiation of pluripotent stem cells (PSC) into retinal and other neural tissues has become a major strategy to recapitulate development. We decided to develop a universal, robust, and non-invasive method to assess retinal differentiation that would not require chemical probes or reporter gene expression. We hypothesized that basic-contrast bright-field (BF) images contain sufficient information on tissue specification, and it is possible to extract this data using convolutional neural networks (CNNs). Retina-specific Rx-green fluorescent protein mouse embryonic reporter stem cells have been used for all of the differentiation experiments in this work. The BF images of organoids have been taken on day 5 and fluorescent on day 9. To train the CNN, we utilized a transfer learning approach: ImageNet pre-trained ResNet50v2, VGG19, Xception, and DenseNet121 CNNs had been trained on labeled BF images of the organoids, divided into two categories (retina and non-retina), based on the fluorescent reporter gene expression. The best-performing classifier with ResNet50v2 architecture showed a receiver operating characteristic-area under the curve score of 0.91 on a test dataset. A comparison of the best-performing CNN with the human-based classifier showed that the CNN algorithm performs better than the expert in predicting organoid fate (84% vs. 67 ± 6% of correct predictions, respectively), confirming our original hypothesis. Overall, we have demonstrated that the computer algorithm can successfully recognize and predict retinal differentiation in organoids before the onset of reporter gene expression. This is the first demonstration of CNN's ability to classify stem cell-derived tissue .