The space between the lens of the eye and the retina is filled with a substance called vitreous, a highly transparent jelly-like material that helps us see clearly. With age, or due to injury, the vitreous may become depleted, requiring surgical replenishment to restore vision. Current interventions have severe limitations, so a team of international researchers headed by scientists at Unviersity of Tokyo, have developed a hydrogel that may be an excellent replacement for vitreous.
Their oligo-TetraPEG hydrogel starts as a liquid that can be injected into the eye, but turns to a gel within about ten minutes. Such fast change in state was accomplished by combining two types of polymers in liquid, which then combine to form a gel once inside the eye.
Unlike many other clear hydrogels tried in the past, oligo-TetraPEG doesn’t swell much when it is around water, an important characteristic for it to be useful in surgical practice. A number of rabbits were injected with the new hydrogel to replace their natural vitreous, and their intraocular pressure remained the same compared to a control group who only had saline injections. The rabbits spent more than a year with their artificial vitreous, seemingly staying perfectly healthy and not exhibiting any signs of rejection. Importantly, rabbits with retinal detachment, a common eye condition in the elderly, managed to recover well following treatment with the new hydrogel.
Study in Nature Biomedical Engineering: Fast-forming hydrogel with ultralow polymeric content as an artificial vitreous body…
Via: University of Tokyo…