Eyeworld

26 | EYEWORLD | JUNE/JULY 2020 N EWS COVID-19 NEWS YOU CAN USE that while aerosols were created by a 2.75-mm phacoemulsification tip, there were no visible aerosols created when using a 2.2-mm tip. They also found that coating the surface of the cor- nea with a viscoelastic can block aerosols, how- ever, this effect was short-lived. Furthermore, we also found that significant visible aerosols were not produced with either longitudinal or torsional phacoemulsification through a 2.2-mm incision. Conclusions/recommendations Removal of aqueous humor with irrigation and aspiration or by displacement with viscoelastic at the beginning of the case are both sufficient to remove potential viral particles from the anterior chamber without the production of aerosols. Longitudinal and torsional phacoemul- sification with a 2.2-mm tip does not generate significant aerosolization. We also recommend the continued use of povidone-iodine to ster- ilize the conjunctiva and ocular surface as per regular protocol. production of aerosols. Although no studies to date have analyzed whether SARS-CoV-2 is present in the aqueous humor, it has been isolated on the conjunctival surface and other viruses have been isolated from the aqueous hu- mor. 2–4 Povidone-iodine solutions are routinely used to disinfect the surface of the eye prior to cataract surgery. Povidone-iodine solutions have been shown to have highly effective viricidal ac- tivity against a broad range of viruses, including coronaviruses such as SARS-CoV-1 and MERS- CoV. 5–6 This viricidal activity likely extends to the novel coronavirus, SARS-CoV-2. The rate of aqueous humor production is 2.4±0.6 µL/ min. 7 By comparison, conventional aspiration rates (20–40 mL/min) during cataract surgery are 3–4 orders of magnitude greater. Therefore, once the initial aqueous humor from the anteri- or chamber has been evacuated (either through initial irrigation and aspiration or by displace- ment with OVD), the rate of viral accumulation in the anterior chamber would be exceedingly low during the surgery. Darcy et al. demon- strated that phacoemulsification tip size can affect the production of aerosols. 8 They found continued from page 25 References 1. van Doremalen N, et al. Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1. N Engl J Med. 2020;382:1564–1567. 2. Judson SD, Munster VJ. Noso- comial transmission of emerging viruses via aerosol-generating medical procedures. Viruses. 2019;11:940. 3. Xia J, et al. Evaluation of coro- navirus in tears and conjunctival secretions of patients with SARS- CoV-2 infection. J Med Virol. 2020;92:589–594. 4. Wu P, et al. Characteristics of ocular findings of patients with coronavirus disease 2019 (Covid-19) in Hubei Province, China. JAMA Ophthalmol. 2020;138:575–578. 5. Parhar HS, et al. Topical prepa- rations to reduce SARS-CoV-2 aerosolization in head and neck mucosal surgery. Head Neck. 2020;42:1268–1272. 6. Eggers M, et al. In vitro bactericidal and virucidal efficacy of povidone-iodine gargle/mouth- wash against respiratory and oral tract pathogens. Infect Dis Ther. 2018;7:249–259. 7. Goel M, et al. Aqueous humor dynamics: A review. Open Oph- thalmol J. 2010;4:52–59. 8. Darcy K, et al. Reducing visible aerosol generation during phacoemulsification in the era of Covid-19. MedRxiv. 2020. Epub ahead of print. Read EyeWorld Daily News from the 2020 ASCRS Virtual Annual Meeting Daily.EyeWorld.org

• Blank Page
• Blank Page (1)
• Blank Page (2)