Corneal blindness is the fourth most common cause of vision loss globally, with over 5% of the world’s population being affected by it. Unlike glaucoma, cataract, and Age-Related Macular Degeneration which affects older people, corneal blindness affects the younger population, majorly from rural areas, especially from those who have no adequate access to healthcare. This creates significant health and economic burden on the community and threatens economic productivity.
The cornea (window of the eye) is a transparent tissue that covers the front part of the eye. It is responsible for the refraction of light rays from an object – this is important because it allows the rays to be focused on the retina on which the object’s image is formed and taken to the brain for interpretation. This explains how the cornea is very important for vision. Once the cornea becomes clouded (opaque) – just as is the case in corneal blindness – light rays from an object cannot get through the eyes’ window to be focused on the retina. The result is blindness.
Corneal blindness treatment procedures have remained a major challenge for physicians. So far, the only possible treatment option is cornea replacement with cadaveric donations, which is often not enough to attend to the estimated 12.7 million people who are affected by corneal blindness globally. Sadly, just one in seventy patients get a cornea transplant. However, thankfully, a team of researchers at Linkoping University (LiU) and LinkoCare Life Sciences AB recently developed a cornea-like implant that is capable of restoring vision to patients who have corneal blindness.
To fix the challenge due to the shortage of available donated corneas, this research team, via bioengineering, has created an implant that resembles the cornea both in structure and function. They produced it out of collagen derived from pig skin that has been highly purified and made under strict conditions suitable for use by humans.
According to Mehrdad Rafat, the team prioritized the safety of the implant, including its effectiveness while it was being developed. They made sure that it not only worked well to restore vision but was also safe for humans. Mehrdad Rafat is an adjunct associate professor at LiU’s Department of Biomedical Engineering and the founder of the company LinkoCare LifeSciences AB, which developed the cornea-like implant. He also stated that they made efforts to make sure that the invention is affordable to all, including the low- and middle-income population.
While they were constructing the implant, the researchers were able to keep the loose collagen molecules well stabilized to form a strong and transparent material that can endure the implantation process. Contrary to the donated cornea which can last only up to two weeks after the donation, this novel invention can last for up to two years in storage.
A better way to treat keratoconus revealed
Keratoconus is a medical condition where the cornea becomes so thin, resulting in blindness. Treatment of this condition has always required surgical procedures involving total invasion, which usually leaves patients in pain and swelling during recovery. The team also developed a method to treat this condition with a minimally invasive surgical procedure.
The method, as explained by Neil Lagali who led the research group that developed the surgical method, does not need total removal of the patient’s tissue. Rather, a small incision is made, through which the implant is inserted into the existing cornea. This procedure does not need stitching since the incision can be made with high precision using advanced lasers. They first carried out the procedure on pigs and found that it was simpler and safer than the usual cornea transplant.
A pilot study was done in Iran and India, which are two countries where the masses do not have access to adequate healthcare, to confirm the safety and efficacy of the implants. The study involved 20 people – 14 of them were blind before the study, while the rest were on the verge of losing their sight due to keratoconus. They were all treated using the new method that involved cornea replacement with the novel implant.
At the end of the study, all 20 of them were no longer blind, and there were no complications recorded during the procedure. To prevent rejection of the implant during the procedure, the patients were administered eye drops with an immunosuppressive effect for eight weeks, unlike the conventional cornea replacement procedure which requires that the patients be on medication for several years. The doctors followed up with the patients for two years and they recorded no complications during that period.
Asides from confirming the safety of the procedure via the pilot study, the researchers also noted a surprising observation: they found that the thickness and curvature of the cornea became normal; after the follow-up on the patients for two years, all 20 patients got their vision back totally. Three Indian participants who were blind before the procedure had their vision restored perfectly.
The findings in this study reveal a promising future for all who are suffering from corneal blindness. The novel invention has been proven to be effective for the treatment, and most importantly, safe for use.
In conclusion, people with corneal blindness – particularly those in underdeveloped areas – now have hope of being able to see again, due to the findings and invention of this study.