Optical Coherence Tomography Angiography (OCTA) Findings in Retinitis Pigmentosa.

Optical coherence tomography angiography (OCTA) is a noninvasive new imaging modality that can be used to diagnose and monitor progression of retinitis pigmentosa (RP). Cohorts and case series have shown correlation between OCTA findings and visual function and disease severity. Although an early use of the technology is promising, there are concerns about segmentation errors and artifacts. There is also a paucity of data on genotype and how that correlates with OCTA findings. Despite its limitations, OCTA remains a useful tool for clinicians managing retinitis pigmentosa patients.

Bitcoin volatility in bull vs. bear market-insights from analyzing on-chain metrics and Twitter posts.

Cryptocurrencies have emerged as a popular investment vehicle, prompting numerous efforts to predict market trends and identify metrics that signal periods of volatility. One promising approach involves leveraging on-chain data, which is unique to cryptocurrencies. On-chain data, extracted directly from the blockchain, provides valuable information, such as the hash rate, total transactions, or the total number of addresses that hold a specified amount of cryptocurrency. Some studies have also explored the relationship between social media sentiment and Bitcoin, using data from platforms such as Twitter and Google Trends. However, the quality of Twitter sentiment analysis has been lackluster due to suboptimal extraction techniques. This research proposes a novel approach that combines a superior sentiment analysis technique with various on-chain metrics to improve predictions using a deep learning architecture based on long-short term memory (LSTM). The proposed model predicts outcomes for multiple time horizons, ranging from one day to 14 days, and outperforms the Martingale (random walk) approach by over 9%, as measured by the mean absolute percentage error metric, as well as recent results reported in literature. To the best of our knowledge, this study may be among the first to employ this combination of techniques to improve cryptocurrency market prediction.

Analysis of SARS-CoV-2 RNA on surfaces in New York City.

BACKGROUND: This study sought to determine the presence of SARS-CoV-2 virus on surfaces that trainees and faculty of an academic eye clinic came into contact with during daily life at the time of the COVID-19 pandemic in New York City. METHODS: This cross-sectional analysis involved collection of at least two samples by teams on four different days (November 9, 2020 - December 18, 2020) using sterile swabs (Puritan HydraFlock, Garden Grove, CA). Collection sites were grouped into four zones depending on proximity and amount of time personnel spent there. Samples were transported to the laboratory in transport medium and RNA was extracted using the QIAamp DSP Viral RNA Mini Kit (Qiagen, Germantown, MD). Presence of viral RNA was investigated using the Luna Universal Probe One-step RT-qPCR kit (New England Biolabs, Ipwsich, MA). RESULTS: 834 samples were submitted. Two were positive for SARS-CoV-2 RNA. The first was a sample from a patient bathroom sink handle in the main emergency department. The second was a nasal swab sample from a staff member who had been assigned to collect samples. Prior to this positive result, this asymptomatic staff member had tested positive for COVID-19, had quarantined for two weeks, and had received a negative test. CONCLUSION: Though COVID-19 is currently widespread in the United States, this study shows that health care personnel working in New York City at the Columbia University Irving Medical Center have a low chance of encountering viral RNA on surfaces they are in close contact with during daily life.

Acupuncture resulting in eye penetration and proliferative vitreoretinopathy - Surgical and medical management with intraocular methotrexate.

PURPOSE: To highlight the surgical and medical management used in an extensive globe penetrating injury caused by an acupuncture needle. OBSERVATIONS: We report on a case of acupuncture treatment error resulting in needle penetration of the eye, retinal detachment, and progressive post-traumatic proliferative vitreoretinopathy (PVR). This patient required aggressive surgical management with multiple vitrectomies along with adjunctive intravitreal methotrexate to control ongoing PVR. At last follow-up, 15 months after presentation, the patient's BCVA was 20/40 and the periphery was flat with fibrosis stable. CONCLUSIONS AND IMPORTANCE: Open globe injuries are a subtype of ocular trauma which can cause irreparable vision loss. This case highlights the extensive potential complications which can occur following traumatic injury to the retina and choroid, as well as the role of both surgical and medical management of retinal detachment and PVR. In addition, this is the first report of the use of off-label adjunctive intravitreal methotrexate to control post-traumatic PVR. Further research into this treatment approach could reveal a role of adjunctive methotrexate in the management of such injuries.

Effect of 6-week washout period on intraocular pressure following chronic prostaglandin analogue treatment: a randomized controlled trial.

OBJECTIVE: To evaluate the effect of a 6-week washout period on intraocular pressure (IOP) following long-term monotherapy prostaglandin use. DESIGN: Prospective, randomized, controlled, single-centre, single-blinded, parallel-group clinical study. PARTICIPANTS: Subjects aged >18 years diagnosed with open-angle glaucoma or open-angle glaucoma suspects based on elevated IOP in one or both eyes, using monotherapy topical latanoprost, bimatoprost, or travoprost once daily. METHODS: Subjects were prospectively randomized to continue prostaglandin analogue (PGA) monotherapy (control group) or discontinue PGA monotherapy (washout group) for 42 days. IOP was measured at day 0 (day of randomization), 7, 21, and 42. MAIN OUTCOME MEASURE: Mean IOP (mm Hg) ± standard deviation. RESULTS: 154 eyes (87 participants) completed the study, with 69 eyes (39 participants) in the control group and 85 eyes (48 participants) in the washout group. In the control group, day 0 IOP (14.64 ± 2.68 mm Hg) did not significantly differ from IOP at days 7 (14.25 ± 3.01 mm Hg), 21 (14.57 ± 2.61 mm Hg), and 42 (14.78 ± 2.30 mm Hg) (all p > 0.30). In the washout group, mean IOP values at days 7 (16.19 ± 3.80 mm Hg), 21 (17.28 ± 3.55 mm Hg), and 42 (17.84 ± 3.31 mm Hg) were significantly greater than those at day 0 (14.48 ± 1.94 mm Hg) and day-matched control group values (all p < 0.002). In the washout group, 24.7% of eyes had a day 42 IOP ≥21 mm Hg. No eyes in the control group had a day 42 IOP ≥21 mm Hg. CONCLUSIONS: Six weeks of PGA washout after long-term monotherapy resulted in a small but statistically significant IOP increase. Majority of washout group participants maintained an IOP lower than 21 mm Hg after the 6-week washout duration. (https://clinicaltrials.gov/ identifier, NCT03534882).

Prospective evaluation of aflibercept in pigment epithelial detachments secondary to neovascular age related macular degeneration.

OBJECTIVE: To assess the efficacy of intravitreal aflibercept in treating visual loss and structural changes in patients with pigment epithelial detachments (PED) secondary to neovascular age-related macular degeneration (nAMD). METHODS: Prospective, exploratory, open-label study (ClinicalTrials.gov Identifier: NCT02142296). Participants with PED secondary to nAMD were enrolled and received intravitreal aflibercept injection on a monthly basis for 3 months, followed by injections on a bimonthly basis for another 9 months. Best-corrected visual acuity (BCVA), ophthalmic examinations, optical coherence tomography (OCT) imaging, and fluorescein angiography were performed based on a predetermined schedule. RESULTS: Thirty-six participants (37 eyes) were enrolled. At the end of study, 74.3% eyes demonstrated PED height reduction of 25% or more and 34.3% demonstrated complete resolution. The average reduction in retinal thickness was 128.4 µm. Participant eyes who had at least a 25% reduction in PED height at month 4 were labelled as "responders" (73.0%, n = 27), and those who had less than 25% reduction in PED height were labelled as "partial-responders" (27.0%, n = 10). Responders demonstrated more significant reduction in PED height than partial-responders (p <0.0001). The average gain in BCVA was 10.1 Early Treatment Diabetic Retinopathy Study (ETDRS) letters. Responders demonstrated more gain in BCVA than partial-responders (p = 0.0018). Among the responders, 57.7% demonstrated disease recurrences with increase in PED height during bimonthly dosing. CONCLUSIONS: Intravitreal aflibercept injection for patients with PEDs secondary to nAMD has high response rate with few adverse events. Responders demonstrated BCVA gains, as well as structural improvements. However, high recurrence rate was found on bimonthly maintenance dosing.

The use of anterior segment optical coherence tomography (ASOCT) in demonstrating recurrence of vitreoretinal lymphoma (VRL) in the anterior vitreous.

BACKGROUND: Primary vitreoretinal lymphoma (VRL) is a rare disease with 30-380 new cases in the United States per year. Its insidious process and spread to the central nervous system (CNS) leads to a mean 5-year survival rate from 41.4 to 71%. Medical treatment of VRL has been summarized extensively in the literature and involves intraocular rituximab and methotrexate as first line agents in unilateral VRL, with systemic chemotherapy to be considered in bilateral or CNS-involving disease. In addition, therapeutic "debulking" vitrectomy has been reported in the literature, with some limited success. Despite this, recurrence rate is high and should always be suspected in the setting of new inflammation. Anterior segment optical coherence tomography (ASOCT) has not been previously used to image VRL recurrence in the anterior vitreous. CASE PRESENTATION: A 63-year-old man, with VRL was found to have cells and debris in the anterior vitreous, 10 months after his first vitrectomy, intravitreal rituximab and methotrexate. Since the patient was phakic at the time of initial vitrectomy, the anterior vitreous had not been removed. ASOCT confirmed the findings. Subsequent surgery removed the lens and debris. Both the patient's vision and ASOCT improved. CONCLUSIONS: We suggest that ASOCT of the anterior segment is a useful diagnostic tool to monitor for recurrence of VRL. In biopsy-proven VRL, phakic patients who undergo therapeutic vitrectomy, should also be considered for lens extraction and anterior vitrectomy to limit recurrences.

Survey of occupational musculoskeletal pain and injury in Canadian ophthalmology.

OBJECTIVE: Surgeons and other physicians have reported occupational musculoskeletal (MSK) pain, and it has been recently raised as a growing issue by ophthalmologists and optometrists. What is most concerning is that it could be a serious threat to career longevity and performance. MSK pain and injury in Canadian ophthalmologists has not been quantified. Our goal was to estimate the prevalence of MSK issues, to determine the impact of MSK injuries to working hours and health, and to ascertain physician characteristics and practice patterns associated with MSK problems. DESIGN: Survey. PARTICIPANTS: One hundred sixty-nine ophthalmologists and 121 optometrists. METHODS: A voluntary internet-based (Survey Monkey) survey was conducted. All Canadian ophthalmologists and ophthalmology residents were contacted via the Canadian Ophthalmological Society, and all optometrists registered through the Canadian Association of Optometrists were contacted through their respective listserve email. RESULTS: One hundred sixty-nine ophthalmologists (response rate 17%) and 121 optometrists (2.4%) responded to a voluntary internet-based survey. Fifty percent of the ophthalmology respondents reported clinic-associated MSK pain in the preceding 12 months, compared to 61% of optometry respondents (p = 0.06). Of the ophthalmologists, 48.3% said they had experienced occupational MSK pain in the preceding 12 months, which they directly attributed to their operating room activities. Neck pain was reported in 46%, lower back in 36% and shoulder pain in 28% of ophthalmology respondents. This was compared to 34% (p = 0.04), 37% (p = 0.90) and 41% of optometrists (p= 0.02). Respondents in our survey listed "performing the same task over and over", "working in cramped or awkward positions" and "bending or twisting your neck" as the most common causes of MSK pain. CONCLUSION: Our survey identified that a large proportion of respondents reported MSK pain associated with clinical and surgical duties. Physician-led research is needed before industry and administrative partners can develop equipment and work-spaces that are better suited to the needs of physicians.

Tono-Pen versus Goldmann Applanation Tonometry: A Comparison of 898 Eyes.

PURPOSE: To compare the agreement in intraocular pressure (IOP) measurements obtained with the Tono-Pen (Reichert, Inc, Depew, NY) and Goldmann applanation tonometry (GAT). The influence of central corneal thickness (CCT) on IOP agreement between the 2 tonometry methods also was evaluated. DESIGN: Database study. PARTICIPANTS: A total of 898 patients from the Research, Innovation and Experimentation Database spanning 1999 through 2016. METHODS: A total of 898 IOP measurements of right eye obtained with GAT and the Tono-Pen were extracted from a glaucoma, glaucoma suspect, and ocular hypertension clinical database. The agreement between IOP measurements obtained by the 2 methods was analyzed using a Bland-Altman plot in Microsoft Excel (Microsoft, Redmond, WA). Their relationship to CCT was evaluated using linear regression analysis. MAIN OUTCOME MEASURES: Agreement between GAT and Tono-Pen measurements of IOP and influence of CCT on tonometry methods. RESULTS: The correlation between both tonometry devices was 0.76 (P < 0.001). The mean difference (Tono-Pen minus GAT) in IOP measurement was -0.15 mmHg (95% confidence limits, ±6.8 mmHg). The Tono-Pen underestimated GAT measurements at IOP of more than 16.8 mmHg and overestimated at IOP of less than 16.8 mmHg. Larger differences were associated with higher IOPs. An average difference of more than 3 mmHg by the Tono-Pen was observed for IOPs of 29 mmHg or more. A thicker cornea also was associated with higher IOP. A change of 0.16 mmHg for a 10-µm increase in CCT was appreciated for GAT, and one of 0.15 mmHg per 10 µm was appreciated for the Tono-Pen (all P < 0.001). CONCLUSIONS: In a large cohort of more than 898 measurements, the average difference between IOP measured by GAT and the Tono-Pen was less than 1 mmHg, although the limits of agreement were wide. Higher IOPs were associated with larger differences.

Washout Duration of Prostaglandin Analogues: A Systematic Review and Meta-analysis.

TOPIC: Prostaglandin analogues (PGAs) are first-line medical therapy for primary open angle glaucoma (POAG) and ocular hypertension (OHT). Intraocular pressure (IOP) lowering effects in full responders are known to be 25-33% for this class; however, partial responders and nonresponders do exist. In clinical trials or prospective series, discontinuation and washout of PGAs is necessary to evaluate true change in IOP from novel surgeries and medical therapies. CLINICAL RELEVANCE: To identify all relevant papers with pertinent data on washout of PGAs and quantify the duration and long-term effect of reported PGA washout periods in glaucoma and OHT patients. METHODS: A systematic review and meta-analysis was conducted to investigate the long-term effects on IOP after discontinuation of topical PGAs POAG and OHT patients. The main search was conducted in MEDLINE/PubMed, EMBASE, Cochrane Library, CINAHL, Web of Science, and BIOSIS Previews and conference proceedings. RESULTS: 1055 papers were identified, 548 were independently screened by two physicians., and 56 papers were analyzed for washout durations. The mean washout was found to be 4.56 weeks (±1.25), with the mode and median being 5 weeks. Five studies were analyzed as randomized control trials in which latanoprost was discontinued for 4 weeks prior to restarting another intraocular pressure-lowering drug. Meta-analysis revealed a 4-week discontinuation of latanoprost, on average, subjects returned to their baseline IOP. CONCLUSION: A significant IOP-lowering effect of latanoprost was not observed beyond 4 weeks, suggesting this may be an appropriate washout period for latanoprost. We could not identify appropriate washout periods for either travoprost or bimatoprost, although a majority of articles had 4-week washout durations for the two drugs. Despite the widespread use of this class of medication, there is a paucity of literature on the effects of PGA washout in patients that are treatment naïve to other topical medications.

Hadoop Oriented Smart Cities Architecture.

A smart city implies a consistent use of technology for the benefit of the community. As the city develops over time, components and subsystems such as smart grids, smart water management, smart traffic and transportation systems, smart waste management systems, smart security systems, or e-governance are added. These components ingest and generate a multitude of structured, semi-structured or unstructured data that may be processed using a variety of algorithms in batches, micro batches or in real-time. The ICT architecture must be able to handle the increased storage and processing needs. When vertical scaling is no longer a viable solution, Hadoop can offer efficient linear horizontal scaling, solving storage, processing, and data analyses problems in many ways. This enables architects and developers to choose a stack according to their needs and skill-levels. In this paper, we propose a Hadoop-based architectural stack that can provide the ICT backbone for efficiently managing a smart city. On the one hand, Hadoop, together with Spark and the plethora of NoSQL databases and accompanying Apache projects, is a mature ecosystem. This is one of the reasons why it is an attractive option for a Smart City architecture. On the other hand, it is also very dynamic; things can change very quickly, and many new frameworks, products and options continue to emerge as others decline. To construct an optimized, modern architecture, we discuss and compare various products and engines based on a process that takes into consideration how the products perform and scale, as well as the reusability of the code, innovations, features, and support and interest in online communities.