Just over two years into the global pandemic, we know that the coronavirus attacks many organs, affecting the respiratory tract and causing disorders psychological. Systemic disease causing vascular lesions by coagulation, and obstructing veins and arteries, it is now part of our daily lives. Recently, researchers looked at cases of blindness in Covid-19 survivors.
Study published in the JAMA Network journal highlights the link between impaired vision and positive cases of the virus . The American team from the University of Michigan (USA) followed patients for six months after infection in order to analyze the vascular occlusions of the eye. This work alerts us to the formation of clots that can cause ocular blood to dry up, leading to partial or even total loss of sight.
The virus acts on the vascular system in two ways. At first, it makes the blood clot , which leads to the formation of clots or the appearance of fatty deposits in the blood vessels:this is disseminated intravascular coagulation (DIC). Each organ can therefore potentially suffer damage related to the low blood supply. Secondly, it insinuates itself into the endothelial cells (used to regulate blood flow) and poisons them, causing what is called vasculitis. This is why the whole of the blood network is here also possibly affected by the inflammation of the wall of the vessels, and in particular the eyes which have an already significantly fragile and narrow multiple network. This can cause retinal vascular thrombosis , the obliteration of the main artery of the eye, which consequently irrigates the organ poorly and can cause irreversible blindness.
“ Patients with COVID-19 are predisposed to the formation of emboli due to intravascular coagulation and hypoxia. The combination of vascular damage from COVID-19 and higher emboli formation tendencies may hypothetically increase the risk of retinal vascular occlusion ” , believe the researchers.
According to scientists, symptoms are felt immediately in one eye with a decline in sight without apparent pain . However, these disorders can disappear without causing sequelae if they are taken care of quickly by taking anticoagulants. Some have already been able to regain their pre-Covid eye health. Despite everything, for severe cases of ocular venous obstructions that have caused total blindness, no solution has yet emerged.
