iNDICA NEWS BUREAU-
To ascertain whether coronavirus can be present in various layers of the eye, the All India Institute of Medical Sciences said on Tuesday, September 7, that it has been for the past few months conducting a study on samples of enucleated eyeballs collected from those who succumbed to COVID-19.
Conducted by the hospital’s ophthalmology department, the study will be conducted on corneoscleral rims of eyes, the center’s chief, JS Titiyal said.
Addressing a press conference on the 36th Eye Donation Fortnight celebration by the National Eye Bank (NEB), he said that five eyeballs 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.
Of the tissues retrieved between July 2020 and July 2021 by AIIMS, it was found that 5.5 percent of the presumed COVID-19 negative donors tested RT-PCR positive for SARS-CoV2. The tissue of these patients was not used for corneal transplantation and it was subject to further microbiological analysis.
“These eyeballs will be subjected to various molecular tests to detect the presence of the Covid virus in these tissues and also look for genetic evidence,” Titiyal said.
Dr Namrata Sharma of the R P Centre said that there is no proven evidence so far that establishes any direct link between COVID-19 leading to blindness.
“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 from 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 percent of the presumed COVID-19 negative donors tested RT-PCR positive for SARS-CoV2,” Sharma said.
In India, an estimated 6.8-million people have unilateral corneal blindness and at least a million people have bilateral corneal blindness.
In the first study, the samples of the whole eyeball are being taken while in the second study, the samples of corneoscleral rims are practical
Once there is a receptor on the eyes the virus can get attached and it may remain there.
For the first and primary study, samples of two eyeballs are being evaluated, while for the second study, the samples of 24 eyeballs have been taken.
The team under Dr JS Titiyal, chief Dr RP Centre, AIIMS is conducting both studies.