Biannually-injected hydrogel could keep glaucoma at bay
Presently, glaucoma is treated via daily-administered eye drops, surgery, or implanted devices – none of which are guaranteed to be successful. In the future, however, it's possible that a twice-yearly injection could do the trick.
Glaucoma occurs when a fluid known as aqueous humor can't drain from the eye as it normally would. Instead, it builds up, creating pressure. If that pressure isn't relieved, the optic nerve may be damaged, resulting in blindness.
Ordinarily, the fluid drains mainly through a structure at the front of the eye, called the trabecular meshwork. Because that's typically blocked or otherwise compromised in glaucoma patients, many treatments instead focus on a narrower structure between the front and back of the eye, known as the suprachoroidal space (SCS).
Led by professors Ross Ethier and Mark Prausnitz, scientists at the Georgia Technical Institute have developed an experimental technique in which a tiny droplet of a natural polymer known as hyaluronic acid is injected into the SCS, forming a viscous (but non-toxic) hydrogel once within the eye. That gel proceeds to hold the SCS wide open, allowing the aqueous humor to continuously drain out.
The hypodermic needle that's used is very small – less than a millimeter long – and the injection process takes just a few minutes. In rabbit tests conducted so far, the pressure-reducing effect has lasted for four months before another injection was required. That said, it is hoped that once the technology is developed further, the effect could last up to six months.
"The holy grail for glaucoma is an efficient way to lower the pressure that doesn't rely on the patient putting drops in their eyes every day, doesn't require a complicated surgery, has minimal side effects, and has a good safety profile," says Ethier. "I am excited about this technique, which could be a game-changer for the treatment of glaucoma."
A paper on the research was recently published in the journal Advanced Science.