We read the recent article on the “Evolving consensus on managing vitreo-retina and uvea practices in post COVID-19 pandemic era” with great interest. We wish to highlight the part concerning wrapping of ophthalmic equipment's by Dr. Manisha Agarwal as it was based on our prior experience. We have been using this technique at our hospital for the past few months and would like to elaborate further about our experience.
Doremalen et al. observed that the COVID-19 virus stayed viable on surfaces like plastic and steel as fomites (72-96 hours) for a longer duration than as aerosol (3 h). Respiratory aerosols can easily escape from an ill-fitting/ineffective mask. The close proximity of the patient's nose to the optical coherence tomography (OCT) machine can cause fomites to settle on its front surface and lens. Repeated cleaning of the lens and the sensors of the OCT machine can cause micro-abrasions and leave surface residues. Covering the front part of the machine with a thin plastic sheet or cling-on wrap acts as a barrier to contamination, also protecting the optical surface of the machine from undue damage caused by repeated cleaning.
We observed no significant difference in the image quality obtained with and without the front cover for both OCT and OCT-A [Figs. 1 and 2a]. Thinner and taut (devoid of folds) plastic sheet placed close to the lens provided best image quality. This technique was found to be effective for both SS-OCT (swept source OCT) and SD-OCT (spectral domain OCT).
The cover can be cleaned between examinations with a clean tissue paper and isopropyl alcohol and can easily be replaced when required.
Fundus pictures obtained have a light-flash artifact in the center of the image [Fig. 2b]; hence, we do not recommend its use for taking fundus photographs. Machines utilizing lasers to capture image should not have this artifact.
We found this to be an easy, inexpensive, and effective method. Along with preventing the contamination, it also protects the optical system; hence, this modification can be utilized even in the post-COVID-19 era.
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Conflicts of interest
There are no conflicts of interest.
1. Gupta V, Rajendran A, Narayanan R, Chawla S, Kumar A, Palanivelu MS, et al Evolving consensus on managing vitreo-retina and uvea practice in post-COVID-19 pandemic era Indian J Ophthalmol. 2020;68:962–73
2. van Doremalen N, Bushmaker T, Morris DH, Holbrook MG, Gamble A, Williamson BN, et al Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1 N Engl J Med. 2020;382:1564–7
3. Last accessed on 2020 Jun 12 Available from: https://youtu.be/ROyT-Cr20kA