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The population dynamics of the lower energy excited states of atomic strontium, namely, 1D2, 3DJ, 3P2, 3P1 and 3P0, have been investigated by time-resolved laser-induced fluorescence following pulsed laser excitation to the Sr[5s5p(1P1)] state at 760 K in presence of the noble gases Ne, Kr and Xe. In addition, the 1P1 and 3P1 states were monitored by spontaneous emission under intentionally quantified conditions of radiation trapping for Sr(1P1). The kinetic model employed yields a set of kinetic rate constants, radiation data, collisional propensity rules and the correlation of collisional cross-sections for all the noble gases with potential well depth. [Copyright &y& Elsevier]

Purpose: To evaluate the utility of extended field swept-source Optical Coherence Tomography Angiography (SS-OCTA) imaging biomarkers in predicting the occurrence of clinically significant outcomes in eyes with Non-Proliferative Diabetic Retinopathy (NPDR)., Design: Retrospective clinical case-control study., Methods: Single-center clinical study. 88 eyes with NPDR from 57 participants (median age: 64.0 years; mean duration of diabetes: 15.8 years) with at least two consecutive SS-OCTA scans over a follow-up period of at least six months were included. The presence of intraretinal microvascular abnormalities (IRMAs) at baseline and the stability of IRMAs during follow-up period on 12 × 12-mm angiograms were evaluated. Baseline nonperfusion ischemia index (ISI) and other SS-OCTA metrics were calculated on FIJI and ARI Network. Significant clinical outcomes were defined as occurrence of one or more of the following events at the last available clinical visit:1. significant DR progression (2-step DR progression or progression to proliferative DR (PDR)); 2) development of new center-involving diabetic macular edema (CI-DME); and 3) initiation of treatment with PRP or anti-VEGF injections during the follow-up period. Mixed-effects Cox regression models was used to explore these outcomes., Results: Following a clinical follow-up period lasting 25.1 ± 10.8 months, we observed significant clinical outcomes in 17 eyes (19.3%). Among these, 7 eyes (8.0%) experienced significant progression and 4 eyes (4.5%) developed CI-DME. Anti-VEGF injections were initiated in 15 eyes (17.0%), while PRP was initiated in 2 eyes (2.3%). Upon adjusting for age, the duration of DM, and prior Anti-VEGF treatments, our analysis revealed that non-stable IRMAs during the follow-up periods and a higher ischemia index at baseline were significantly associated with the occurrence of significant clinical outcomes with HRs of 3.88 (95% CI: 1.56-9.64; p=0.004) and 1.05 (95% CI: 1.02-1.09; p=0.004), respectively., Conclusions: In conclusion, NPDR eyes with non-stable IRMAs over time and more ischemia at baseline are in higher risk of developing significant clinical outcomes. Our findings suggest that expanded field SS-OCTA may offer additional prognostic benefits for clinical DR staging and predicting high-risk patients., Competing Interests: Conflict of Interest No conflicting relationship exists for any author., (Copyright © 2024. Published by Elsevier Inc.)

Background and Objective: A cross-sectional prospective study to examine ergonomic differences in vitreoretinal settings: surgery, clinic, and dedicated procedure clinic., Patients and Methods: Three vitreoretinal surgeons, three fellows, and one resident at a tertiary eye care facility. Participants wore an Upright Go 2 posture device and posture was recorded in each setting between July 1 to August 31, 2023., Results: Time in upright and poor postures was tracked. Significant differences were found in postural score for attendings between work settings ( P < 0.01). Trainees showed no significant difference between settings. Poor posture in surgery was linked to microscope use and scleral buckle placement; in the clinic, it was associated with pan-retinal photocoagulation and injection minutes; in procedure clinic, it was ophthalmologist-dependent and those performing injections., Conclusions: Ergonomic considerations are crucial in vitreoretinal practice. Attendings and trainees should focus on posture in surgery and clinic settings to enhance career longevity. [ Ophthalmic Surg Lasers Imaging Retina 2024;55:XX-XX.] .

Background and Objective: To evaluate the association between widefield swept-source optical coherence tomography angiography (WF SS-OCTA) and visual function in healthy eyes., Patients and Methods: Fifty-seven eyes of 45 patients were evaluated with visual acuity (VA), contrast sensitivity (CS), and WF SS-OCTA (3 × 3, 6 × 6, and 12 × 12 mm images) on the same day. Mixed-effects multivariable regression analyses were performed., Results: Contrast sensitivity metrics, including CS between 6 to 18 cycles per degree (cpd) and area under the logarithm CS function, were significantly associated with vessel density (VD) and vessel skeletonized density (VSD), whereas VA was not. The largest effect size was between CS at 18 cpd and VD (β = 0.41, P = 0.007) and VSD (β = 0.42, P = 0.006) on 12 × 12 mm images., Conclusions: Reduced VSD and VD on WF SSOCTA was significantly associated with decreased CS, whereas VA was not. These results suggest CS could serve as a screening tool for early stage retinal and neurologic disorders. [ Ophthalmic Surg Lasers Imaging Retina 2024;55:494-502.] .

Introduction: To investigate whether there is visual function impairment in patients with posterior vitreous detachment (PVD) using the active-learning quantitative contrast sensitivity function test. Methods: In this cross-sectional study, contrast sensitivity was measured in eyes with PVD and eyes without PVD using the quantitative contrast sensitivity function algorithm on the Adaptive Sensory Technology platform. Outcomes included the area under the log contrast sensitivity function curve, contrast acuity, and contrast sensitivity thresholds at 1 to 18 cycles per degree (cpd). Snellen visual acuity (VA) was also measured. Mixed-effects multiple linear regression analyses were performed to evaluate the association between the presence of PVD and visual function, controlling for age and lens status. Results: The cohort comprised 232 healthy eyes of 205 participants; of these, 80 eyes of 69 patients had PVD. There was no significant association between VA and PVD presence. However, PVD was significantly associated with decreased contrast sensitivity thresholds at 1.5 cpd (β, -0.058; P = .003) and 3 cpd (β, -0.067; P = .004). Contrast sensitivity thresholds at lower (1 cpd) or higher (6, 12, 18 cpd) spatial frequencies did not significantly correlate with PVD presence. Even in the subgroup of symptomatic PVD eyes, VA was not significantly decreased, while quantitative contrast sensitivity function outcomes showed visual function deficits at low spatial frequencies (1.5 cpd and 3 cpd). Conclusions: Contrast sensitivity measured with the quantitative contrast sensitivity function test showed visual function deficits in eyes with PVD that would have been missed with VA testing alone. Incorporating this test in the retina clinic might offer a more comprehensive functional assessment of eyes with PVD, serving as an adjunct outcome metric in clinical decision-making., Competing Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Dr. Kim has received research support from the National Eye Institute (R01EY027739), Department of Defense (W81XWH1910824), CureVac AG, and Ingenia Therapeutics and has a financial arrangement with Pykus Therapeutics. Dr. Husain is a consultant to Allergen, Genetech, and Omeicos Therapeutics and has received financial support from the National Eye Institute, Lions VisionGift, Commonwealth Grant, Lions International, Syneos LLC, and the Macular Society. Dr. Vavvas has served on the Scientific Advisory Board of Olix and Valitor, has been an advisor to Drusolv, and is an inventor on patents of Neuroprotection held by Mass Eye and Ear. Dr. Miller is a consultant to Alcon, Allergan, Topcon, Carl Zeiss, Sunovion, and Genentech. None of the other authors declared potential conflicts of interest with respect to the research, authorship, and/or publication of the article., (© The Author(s) 2024.)

Purpose: To longitudinally investigate the changes in intraretinal microvascular abnormalities (IRMAs) over time, employing swept-source optical coherence tomography angiography in eyes with diabetic retinopathy., Methods: In this retrospective, longitudinal study, we evaluated 12 × 12-mm swept-source optical coherence tomography angiography centered on the macula at baseline and last available follow-up visit for (1) IRMA changes during follow-up, defined as (a) stable, (b) regressed, (c) obliterated, and (d) progressed; and the (2) development of new neovascularization (NV) and their origins. Competing-risk survival analysis was used to assess the factors associated with these changes., Results: In total, 195 eyes from 131 participants with diabetic retinopathy were included. Stable, regressed, obliterated, and progressed IRMA were observed in 65.1%, 12.8%, 11.3%, and 19% of eyes with diabetic retinopathy, respectively. Anti-VEGF injections during the follow-up periods and a slower increase of foveal avascular zone were associated with IRMA regression (P < 0.001 and P = 0.039). Obliterated IRMA were correlated with previous panretinal photocoagulation (P < 0.001) and a lower deep capillary plexus vessel density at baseline (P = 0.007), as well as with follow-up anti-VEGF injections (P = 0.025). A higher baseline ischemia index (ISI) and panretinal photocoagulation during the follow-up periods were associated with IRMA progression (P = 0.049 and P < 0.001). A faster increase in ISI predicted the development of NV elsewhere (NVE) from veins (P < 0.001). No significant factors were found to be associated with NVE originating from IRMA., Conclusions: Changes in IRMA closely correlated with the severity of retinal ischemia and treatment. Notably, our study confirmed the potential, yet relatively rare, development of NVE from IRMA in a large cohort; however, the risk factors associated with this transformation require further exploration.

Purpose: To investigate the impact of anti-VEGF therapy on vascular metrics in eyes with macular edema secondary to central retinal vein occlusion (CRVO) using wider field swept-source OCT angiography (WF SS-OCTA)., Methods: We included 23 eyes with macular edema associated with non-ischemic CRVO from 22 patients treated with anti-VEGF therapy (median number of injections: 5 [2-9]). Changes in vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ) parameters were measured using WF SS-OCTA. Visual acuity (VA) and central subfield thickness (CST) were also measured., Results: Median CST decreased significantly from 369 µm (305-531) to 267 µm (243-300, p < 0.001). VD and VSD parameters in 12 × 12 mm images showed significant reductions. For instance, VSD in the whole retina decreased from a median of 13.37 (11.22-13.74) to 11.29 (9.36-12.97, p = 0.013). Additionally, a significant increase in FAZ circularity was found, suggesting improved microvascular integrity. Significant inverse correlations were found between the number of anti-VEGF injections and all VSD and VD parameters on the 12 × 12 mm images (p < 0.05). Notably, the reductions in VSD and VD on 12 × 12 mm angiograms in the deep capillary plexus (DCP) after each injection significantly correlated with increased logMAR VA (worse VA)., Conclusion: Anti-VEGF therapy in CRVO patients not only mitigates macular edema but also alters the overall microvascular morphology and functionality as revealed by WF SS-OCTA., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)