IMPORTANCE Vitreoretinal surgery can be technically challenging and is limited by physiologic characteristics of the surgeon. Factors that improve accuracy and precision of the vitreoretinal surgeon are invaluable to surgical performance.OBJECTIVES To establish weight-adjusted cutoffs for caffeine and β-blocker (propranolol) intake and to determine their interactions in association with the performance of novice vitreoretinal microsurgeons. DESIGN, SETTINGS, AND PARTICIPANTSThis single-blind cross-sectional study of 15 vitreoretinal surgeons who had less than 2 years of surgical experience was conducted from September 19, 2018, to September 25, 2019, at a dry-laboratory setting. Five simulations were performed daily for 2 days. On day 1, performance was assessed after sequential exposure to placebo, low-dose caffeine (2.5 mg/kg), high-dose caffeine (5.0 mg/kg), and high-dose propranolol (0.6 mg/kg). On day 2, performance was assessed after sequential exposure to placebo, low-dose propranolol (0.2 mg/kg), high-dose propranolol (0.6 mg/kg), and high-dose caffeine (5.0 mg/kg).INTERVENTIONS Surgical simulation tasks were repeated 30 minutes after masked ingestion of placebo, caffeine, or propranolol pills during the 2 days.MAIN OUTCOMES AND MEASURES An Eyesi surgical simulator was used to assess surgical performance, which included surgical score (range, 0 [worst] to 700 [best]), task completion time, intraocular trajectory, and tremor rate (range, 0 [worst] to 100 [best]). The nonparametric Friedman test followed by Dunn-Bonferroni post hoc test was applied for multiple comparisons. RESULTSOf 15 vitreoretinal surgeons, 9 (60%) were male, with a mean (SD) age of 29.6 (1.4) years and mean (SD) body mass index (calculated as weight in kilograms divided by height in meters squared) of 23.15 (2.9). Compared with low-dose propranolol, low-dose caffeine was associated with a worse total surgical score (557.0 vs 617.

BACKGROUND AND OBJECTIVE: To determine which optical parameter profiles (OPPs) can be utilized to improve the visualization of epiretinal membranes (ERMs) and the internal limiting membrane (ILM) using a three-dimensional heads-up microscope during 25-gauge pars plana vitrectomy. PATIENTS AND METHODS: Fourteen independent graders were asked to complete a questionnaire comparing each of the OPPs against the unaltered control image for each given surgical case. RESULTS: Analysis of the graders' responses indicated that higher values of hue are correlated with better visualization of ERM/ILM before and after dye application. There was overall agreement that OPPs could be used to enhance the visualization of the ERM and ILM during surgery. CONCLUSIONS: The use of OPPs to improve the visualization of specific structures is still new and heavily dependent on surgeon preference. The authors' study shows that some OPPs may enhance the visualization of the ERM and ILM during macular surgery. [ Ophthalmic Surg Lasers Imaging Retina. 2020;51:584–587.]

Purpose To evaluate diathermy to minimize sclerotomy leakage during small-gauge vitrectomy and prevent ocular hypotony. Methods This observational prospective study included 327 patients (327 eyes) who underwent diathermy to close the sclerotomy sites during 23-gauge pars plana vitrectomy (PPV). All patients were operated by a single surgeon (ED) and evaluated at 30 and 60 days postoperatively. Patients with glaucoma, topical/systemic steroids use exceeding 30 days, ocular inflammation, or trauma were excluded. Chi-square, Kruskal–Wallis, Fisher Exact test, and multivariate statistical analyses were performed to evaluate potential risk factors. The primary outcomes were open sclerotomies, leakage, and ocular hypotony. Results Sclerotomies remained open in 12 (3.6%) and 2 (0.6%) patients, respectively, at 30 and 60 days postoperatively, revealing no case of ocular hypotony. Leakage only occurred in four patients (1.2%) during week 1 postoperatively. Multivariate analysis indicated that additional vitreoretinal surgeries and longer surgeries were risk factors for persistent sclerotomy opening. Conclusion Diathermy was safe and feasible to close sclerotomies. Vitreoretinal surgery reoperations and longer surgeries were the most significant ( P <0.05) risk factors for persistent sclerotomy opening, which may be functionally closed without evidence of leakage or ocular hypotony.

Background Noninfectious endophthalmitis may be misdiagnosed, leading to serious clinical implications. So far, its causative factors remain unknown. Therefore, this study assessed the role of silicone oil and syringe agitation in the development of inflammation after intravitreal injection of aflibercept. Methods A randomized, double-blind, controlled clinical trial included subjects with an indication of intravitreal antiangiogenic therapy prior to vitrectomy for proliferative diabetic retinopathy. Aflibercept was injected 48 h before surgery. The control group received the injection without agitation, while the intervention group was injected with a previously agitated syringe by flicking with either a siliconized or silicone oil-free syringe. The primary endpoint was the presence of anterior chamber reaction (ACR) at 48 h. Aqueous samples were collected and underwent cytometric bead array analysis for quantification of interleukins and chemokines. Results Forty-one individuals were included (21 in the agitation group and 20 in the no-agitation group). None of the included eyes showed baseline signs of AC cells, hyperemia or pain complaint, while 10% of control group and 80% of agitation group showed AC cells 48 h after injection of aflibercept with SR syringe. There were no differences in the mean variations of all cytokines and chemokines by agitation status. However, there was a marginally significant increase between the mean variations of IP-10 (p = 0.057) and IL-8 (p = 0.058) in the siliconized one. Conclusion This clinical trial discloses a potential role of agitation and siliconized syringes in the development of inflammation after an intravitreal injection of aflibercept. These findings have important clinical implications for all healthcare practitioners who perform intravitreal injections. Trial Registration: Brazilian Registry of Clinical Trials, RBR-95ddhp. Registered 12 May 2019, http://www.ensaiosclinicos.gov.br/rg/RBR-95ddhp/

Synthetic hydrogels have been proposed as vitreous substitutes recently. This study aims to evaluate the biocompatibility of polyvinyl alcohol (PVA) crosslinked with trisodium trimetaphosphate (SMTP) hydrogel in rabbit vitrectomized eyes. Seven animals were submitted to pars plana vitrectomy and the vitreous was replaced by PVA/SMTP hydrogel. Optical coherence tomography, fluorescein angiogram, clinical, and electrophysiological (ERG) examinations were analyzed at baseline, on postoperative days 7 and 30. The fellow eye was used as the control group. Hydrogel opacification was observed and ERG recordings were reduced in the hydrogel group in rod response, b‐wave cone response and flicker. A histological analysis showed retinal disorganization, presence of multinucleated cells, and intraretinal hydrogel particles. The PVA/SMTP hydrogel showed poor biocompatibility. Novel biomaterials compounds should be analyzed in vivo.

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Purpose:To quantitatively analyze and compare the novice vitreoretinal surgeons' performance after various types of external exposures.Methods: This prospective, self-controlled, cross-sectional study included 15 vitreoretinal fellows with less than 2 years of experience. Surgical performance was assessed using the Eyesi simulator after each exposure: Day 1, placebo, 2.5, and 5 mg/kg caffeine; Day 2, placebo, 0.2, and 0.6 mg/kg propranolol; Day 3, baseline simulation, breathalyzer reading of 0.06% to 0.10% and 0.11% to 0.15% blood alcohol concentration; Day 4, baseline simulation, push-up sets with 50% and 85% repetition maximum; Day 5, 3-hour sleep deprivation. Eyesi-generated total scores were the main outcome measured (0-700, worst to best).Results: Performances worsened after increasing alcohol exposure based on the total score (x 2 = 7; degrees of freedom = 2; P = 0.03). Blood alcohol concentration 0.06% to 0.10% and 0.11% to 0.15% was associated with diminished performance compared with improvements after propranolol 0.6 and 0.2 mg/kg, respectively (Δ1 = 222 vs. Δ2 = +13; P = 0.02; Δ1 = 243 vs. Δ2 = +23; P = 0.01). Propranolol 0.6 mg/kg was positively associated with the total score, compared with deterioration after 2.5 mg/kg caffeine (Δ1 = +7 vs. Δ2 = 213; P = 0.03).Conclusion: Surgical performance diminished dose dependently after alcohol. Caffeine 2.5 mg/kg was negatively associated with dexterity, and performance improved after 0.2 mg/kg propranolol. No changes occurred after short-term exercise or acute 3-hour sleep deprivation.

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