Ophthalmology practice in COVID-19 pandemic: Performance of rapid antigen test versus real time-reverse transcription polymerase chain reaction in a tertiary eye care institute in South India.

Purpose: To assess the rapid antigen test (RAT) against the gold standard reverse transcription-polymerase chain reaction (RT-PCR) to screen COVID-19 infection in asymptomatic patients undergoing ophthalmic procedures. Methods: This was a retrospective hospital-based study. Point-of-care (PoC) RAT was performed using nasopharyngeal swab, while RT-PCR for SARS-CoV-2 viral RNA was performed using both nasopharyngeal and throat swabs. Results: A total of 629 patients were tested for SARS-CoV-2 by using both RAT and RT-PCR. Only one patient had tested positive for SARS-CoV-2 with both RAT and RT-PCR, while two patients had tested positive with RT-PCR after an initial negative RAT. The positivity rate for RAT was 0.15% (1/629), and that for RT-PCR was 0.47%. Percent agreement or proportion of agreement observed between the two tests was 99.68%, while Cohen's kappa coefficient value was 0.49. The sensitivity of RAT in comparison to RT-PCR was 33.33%, specificity was 100%, positive predictive value was 100%, and negative predictive value was 99.68%. Conclusion: The sensitivity and Cohen's kappa coefficient in our study were low but that can be attributed to the overall low positivity rates with both RAT and RT-PCR. However, percent agreement observed between the two tests was very high. Therefore, we recommend initial screening of all the patients for COVID-19 symptoms followed by RAT before performing any ophthalmic surgical procedure to ensure the safety of the health care professionals as well as the patients.

COVID-19-associated optic neuritis - A case series and review of literature.

Neuroophthalmic manifestations are very rare in corona virus disease-19 (COVID-19) infection. Only few reports have been published till date describing COVID-19-associated neuroophthalmic manifestations. We, hereby, present a series of three cases who developed optic neuritis during the recovery period from COVID-19 infection. Among the three patients, demyelinating lesions were identified in two cases, while another case was associated with serum antibodies against myelin oligodendrocyte glycoprotein. All three patients received intravenous methylprednisolone followed by oral steroids according to the Optic Neuritis Treatment Trail ptotocol. Vision recovery was noted in all three patients, which was maintained at 2 months of the last follow up visit.

Study of the interactions of sneezing droplets with particulate matter in a polluted environment.

We have performed a three-dimensional numerical simulation to determine the effect of local atmospheric pollution level on the spreading characteristics of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus through ejected droplets during sneezing and coughing in an open space. Utilizing a finite volume-based numerical method, we have performed computations for various ranges of droplet diameters and sneezing speeds. The interactions between the droplets and the suspended particles are considered by taking both hydrophobic and hydrophilic wettability characteristics into account. Our computational results show that the virus-containing droplets partially affect aerosols during the path of their transmission. With the progression of time, the droplet distribution shows an asymmetric pattern. The maximum dispersion of these droplets is found for higher sneezing velocities. The droplets with a diameter of 50 µm travel a larger distance than the larger diameter droplets. We have found that an aerosol with hydrophilic wettability undergoes complete wetting by the disease-containing droplets and therefore is conducive to disease propagation. The droplet engagement duration with aerosol decreases with increase in the sneezing velocity. Our study recommends against using physical exercise centers in a closed environment such as gymnasium and indoor games during the COVID pandemic, especially in a polluted environment. The results from our work will help in deciding proper social distancing guidelines based on the local atmospheric pollution level. They may act as a precursor in controlling further spread of diseases during this unprecedented situation of the COVID pandemic.

Exudative retinal detachment in COVID-19 - associated rhino-orbital mucormycosis - A rare clinical finding.

Rhino-orbital-cerebral mucormycosis is a life-threatening, opportunistic invasive fungal infection. Patients with moderate to severe coronavirus disease 2019 (COVID-19) infection are more vulnerable to it. Varied clinical presentations can be seen in patients with orbital mucormycosis starting from conjunctival chemosis, proptosis, ptosis, restriction of extraocular movements, exposure keratitis, neurotrophic keratitis, and central retinal artery occlusion. Exudative retinal detachment in a patient with orbital mucormycosis is a rare clinical entity. We, hereby, report a case of orbital mucormycosis with exudative retinal detachment in a patient post-COVID-19 infection.