The RP Centre for Ophthalmic Sciences at AIIMS is conducting a study to ascertain the presence of coronavirus in various parts of the eye of those people who have died due to the infection, the centre’s chief Dr JS Titiyal said on Tuesday.
Addressing a press conference on the 36th Eye Donation Fortnight celebration by the National Eye Bank (NEB), he said that five eye balls have been collected for carrying out the study.
“The research study will help ascertain the presence of the coronavirus in the cornea, optic nerve and retina of Covid-19 infected deceased,” Titiyal said.
“These eye balls will be subjected to various molecular tests to detect the presence of the Covid virus in these tissues and also look for genetic evidence,” he said.
Dr Namrata Sharma of the RP Centre said that there is no proven evidence so far which establishes any direct link between Covid-19 leading to blindness.
Because of Covid-19, cases of conjunctivitis have been reported but that does not lead to vision loss. Covid-19 leads to mucormycosis and there have been cases where it has impacted vision and led to blindness, she said.
“There have been isolated cases of retinal and Venus blocks which may lead to sudden diminishing of vision due to thromboembolism . But there has been no proven cause and effect relationship between them so far,” Sharma said.
Tissue retrieval is performed only on presumed Covid-19 negative donors, according to established eye banking guidelines, she said.
“To ensure maximum safety, we perform a post-mortem nasopharyngeal swab RT-PCR testing for all our potential donors. Of the tissues retrieved by us between July 2020 and July 2021, we found that 5.5 per cent of the presumed COVID-19 negative donors tested RT-PCR positive for SARS-CoV2,” Sharma said.
The tissues from these donors were not used for corneal transplantation and were subjected to further microbiological analysis, she said.
Eye banking services have been one of the worst hit by the Covid-19 pandemic, Titiyal said.
Corneal tissue retrieval activities by the NEB, which remained suspended from April 2020 to June 2020 during the nationwide lockdown, were restarted through the hospital cornea retrieval program (HCRP) from July 2020 onwards.
From April 2020 to March 2021, the NEB collected 394 corneal tissues, and 311 keratoplasties were performed, amounting to a utilisation rate of 78.9 per cent, Titiyal said.
