Does Prophylactic Oral Zinc Reduce the Risk of Contracting COVID-19?

Objective In this study, we aimed to investigate whether zinc provided in Age-Related Eye Disease Study 2 (AREDS2) vitamins is associated with a decreased risk of contracting coronavirus disease 2019 (COVID-19). Materials and methods We conducted a retrospective observational cohort study involving patients at a retina-only practice who were provided a questionnaire at each visit to assess whether they were symptomatic of or had contracted COVID-19. Those who answered yes to testing positive for COVID-19 were retrospectively analyzed and categorized based on their AREDS2 vitamin use, and a Pearson's chi-squared test was performed. Demographic data and past ocular history were also analyzed. Results A total of 8,426 unique patients, including 2,111 with a diagnosis of age-related macular degeneration (AMD), were seen from April 1, 2020, to April 9, 2021. A total of 110 patients (1.3%) reported contracting COVID-19 and had positive COVID-19 tests. The average age of those who had contracted COVID-19 in this study was 68.3 years; 51.8% were male, 30.1% had AMD, 28.2% had diabetic retinopathy, 24.5% had surgical retinal disease, 11.8% had retinal vascular disease, and 4.5% had other disease states. Of the COVID-19-positive patients, 27.3% (30/110) took AREDS2 vitamins, while 72.7% (80/110) patients did not. A chi-squared analysis was performed, which was not statistically significant (p=0.667). Conclusions Oral zinc supplementation, in the form of AREDS2 vitamins, is not associated with a protective effect against contracting COVID-19.

Visual phenomena perceived during pars plana vitrectomy under peribulbar block and monitored anaesthesia care.

AIM: To investigate patients' sensory phenomena, especially instrument visualisation, and their emotional reactions during pars plana vitrectomy (PPV) under monitored anaesthesia care (MAC). METHODS: One hundred adults who underwent PPV under MAC plus peribulbar block were prospectively recruited on the day after surgery to complete a questionnaire about sensory phenomena and comfort. Anaesthetics used during surgery were correlated with visual phenomena and patient comfort. Surgeons were asked to predict patient intraoperative comfort and ability to hear. RESULTS: Of the 27% of patients who reported visual phenomena, lights (74%), colours (37%) and moving instruments (17%) were common. Instrument visualisation was not associated with any preoperative or intraoperative variables. Visual phenomena were neutrally received by 98% of patients. Neither the use of the intravenous medications during the peribulbar injection and surgery nor the type of local anaesthesia correlated with perceived level of pain. Sixty-six per cent of patients remembered hearing surgeons talk, and 96% of patients reacted neutrally to voices. Patient reports of intraoperative pain were similar to the surgeon's prediction, and mean discomfort during surgery was mild. CONCLUSIONS: The reported prevalence of intraoperative visual phenomena is low when elicited at the first postoperative visit. Surgeons can reliably predict patients' comfort, and most patients react neutrally to visual and hearing phenomena during PPV under MAC with peribulbar block. The combination of medications used may be responsible for the neutral reception of sensory phenomena.

Toxic optic neuropathy: an unusual cause.

A 60-year-old woman with a history of chronic alcoholism and tobacco use presented with the complaint of a painless decrease in vision in both eyes. She lost vision first in the left eye then in the right eye. She admitted consuming at least one 16 ounce bottle of over the counter mouthwash daily and denied consumption of any other alcohols, methanol, or antifreeze. She stated that her vision had been continuing to deteriorate in both eyes. Her best-corrected visual acuity was 4/200 in each eye. Color vision was nil in each eye. Her pupils were sluggish bilaterally, and her optic discs were flat and hyperemic with peripapillary hemorrhages. Her visual fields revealed central scotomas bilaterally. The magnetic resonance imaging of the brain and lumbar puncture were within normal limits. Antinuclear antibody, human leukocyte antigen-B27 genotyping, and B12 were normal; serum thiamine was low. While continuing to ingest mouthwash, her vision decreased to count fingers at 2 feet, and maculopapillary bundle pallor developed. She was started on folate and thiamine supplementation. Once she discontinued mouthwash, her vision improved to 20/400 bilaterally, and her central scotomas improved. This case demonstrates an alcohol-induced toxic optic neuropathy from mouthwash ingestion with some visual recovery after discontinuation of the offending agent.

Nutrient supplementation with n3 polyunsaturated fatty acids, lutein, and zeaxanthin decrease A2E accumulation and VEGF expression in the retinas of Ccl2/Cx3cr1-deficient mice on Crb1rd8 background.

The Age-Related Eye Diseases Study 2 (AREDS2) clinical trial is assessing the effects of higher dietary xanthophyll (lutein and zeaxanthin) and long-chain n3 polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake on progression to advanced age-related macular degeneration (AMD). This study's purpose was to examine the retinal effects of the AREDS2 formulation on Chemokine (C-C motif) ligand 2 (Ccl2(-/-))/CX3C chemokine receptor 1 (Cx3cr1(-/-)) mice on Crumbs homolog 1 retinal degeneration phenotype 8 (Crb1(rd8)) background (DKO), which develop focal retinal lesions with certain features similar to AMD. DKO and C57BL/6N rd8 background mice (WT) were bred and randomized into 4 groups. Two groups, WT mice on AREDS2 diet (A-WT) and DKO mice on AREDS2 diet (A-DKO), were supplemented daily with 1.76 µmol of lutein, 35.1 µmol of zeaxanthin, 215 µmol EPA, and 107 µmol of DHA, and 2 control groups, WT mice on control diet (C-WT) and DKO mice on control diet (C-DKO), were fed an isocaloric diet. All mice had monthly fundus photos and were killed after 3 mo for biochemical and histologic analyses. After 3 mo, 81% of A-DKO mice had lesion regression compared with 25% of C-DKO mice (P < 0.05). Toxic retinal 2-[2,6-dimethyl-8-(2,6,6-trimethyl-1-cyclohexen-1-yl)-1E,3E,5E,7E-octatetra-enyl]-1-(2-hydroxyethyl)-4-[4-methyl-6(2,6,6-trimethyl-1-cyclohexen-1-yl) 1E,3E,5E,7E-hexatrienyl]-pyridinium (A2E) concentrations were significantly lower in A-DKO compared with C-DKO mice. The outer nuclear layer thickness in A-DKO mice was significantly greater than that in C-DKO mice. Retinal expression of inducible nitric oxide synthase (iNos) tumor necrosis factor-α (Tnf-α), Cyclooxygenase-2 (Cox-2), interleukin1beta (IL-1ß), and vascular endothelial growth factor (Vegf) was significantly lower in A-DKO compared with C-DKO mice. Xanthophylls and LCPUFAs have antiinflammatory, neuroprotective, and antiangiogenic properties. Our data provide potential mechanisms by which the AREDS2 formula has a protective effect on retinal lesions in DKO mice.